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Sample records for battery optimized reactor

  1. Optimizing the Design of Small Fast Spectrum Battery-Type Nuclear Reactors

    Directory of Open Access Journals (Sweden)

    Staffan Qvist

    2014-07-01

    Full Text Available This study is focused on defining and optimizing the design parameters of inherently safe “battery” type sodium-cooled metallic-fueled nuclear reactor cores that operate on a single stationary fuel loading at full power for 30 years. A total of 29 core designs were developed with varying power and flow conditions, including detailed thermal-hydraulic, structural-mechanical and neutronic analysis. Given set constraints for irradiation damage, primary cycle pressure drop and inherent safety considerations, the attainable power range and performance characteristics of the systems are defined. The optimum power level for a core with a coolant pressure drop limit of 100 kPa and an irradiation damage limit of 200 DPA (displacements per atom is found to be 100 MWt/40 MWe. Raising the power level of an optimized core gives significantly higher attainable power densities and burnup, but severely decreases safety margins and increases the irradiation damage. A fully optimized inherently safe battery-type fast reactor core with an active height and diameter of 150 cm (2.6 m3, a pressure drop limit of 100 kPa and an irradiation damage limit of 300 DPA can be designed to operate at 150 MWt/60 MWe for 30 years, reaching an average discharge burnup of 100 MWd/kg-actinide.

  2. Optimal control of nuclear reactors

    International Nuclear Information System (INIS)

    The modern control theory is applied to the design of control systems for experimental nuclear reactors that do not belong to power reactors, the component forms of optimal control systems for nuclear reactors are demonstrated. The adoption of output quadratic integral criterion and incomplete state feedback technique can make these systems both efficient and economical. Moreover, approximate handling methods are given so as to simplify the calculations in design. In addition, the adoptable reference values of parameters are given in the illustration

  3. Nickel-Cadmium Battery Operation Management Optimization Using Robust Design

    Science.gov (United States)

    Blosiu, Julian O.; Deligiannis, Frank; DiStefano, Salvador

    1996-01-01

    In recent years following several spacecraft battery anomalies, it was determined that managing the operational factors of NASA flight NiCd rechargeable battery was very important in order to maintain space flight battery nominal performance. The optimization of existing flight battery operational performance was viewed as something new for a Taguchi Methods application.

  4. Microgrid management architecture considering optimal battery dispatch

    Science.gov (United States)

    Paul, Tim George

    Energy management and economic operation of microgrids with energy storage systems at the distribution level have attracted significant research interest in recent years. One of the challenges in this area has been the coordination of energy management functions with decentralized and centralized dispatch. In this thesis a distributed dispatch algorithm for a microgrid consisting of a photovoltaic source with energy storage which can work with a centralized dispatch algorithm that ensure stability of the microgrid is proposed. To this end, first a rule based dispatch algorithm is formulated which is based on maximum resource utilization and can work in both off grid and grid connected mode. Then a fixed horizon optimization algorithm which minimizes the cost of power taken from the grid is developed. In order to schedule the battery based on changes in the PV farm a predictive horizon methodology based optimization is designed. Further, the rule based and optimization based dispatch methodologies is linked to optimize the voltage deviations at the microgrid Point of Common Coupling (PCC). The main advantage of the proposed method is that, an optimal active power dispatch considering the nominal voltage bandwidth can be initiated for the microgrid in both grid connected or off grid mode of operation. Also, the method allows the grid operator to consider cost based optimal renewable generation scheduling and/or the maximum power extraction based modes of operation simultaneously or separately based on grid operating conditions and topologies. Further, the methods allows maintaining PCC voltage within the limits during these modes of operation and at the same time ensure that the battery dispatch is optimal.

  5. Optimal control of reactor temperatures using reactivity

    International Nuclear Information System (INIS)

    Modern control theory provides for better system performance through feedback of the internal system states, state feedback. The classical reactor power control loop normally adjusts control rod reactivity to change power through feedback of the output variable only, output feedback. Improved plant performance could be achieved with tight control of reactor temperatures as well. A new technique to improve performance of reactor temperatures is presented in this paper, which modifies reactor power demand signal to the classical control with optimal state feedback

  6. Optimized batteries for cars with dual electrical architecture

    Science.gov (United States)

    Douady, J. P.; Pascon, C.; Dugast, A.; Fossati, G.

    During recent years, the increase in car electrical equipment has led to many problems with traditional starter batteries (such as cranking failure due to flat batteries, battery cycling etc.). The main causes of these problems are the double function of the automotive battery (starter and service functions) and the difficulties in designing batteries well adapted to these two functions. In order to solve these problems a new concept — the dual-concept — has been developed with two separate batteries: one battery is dedicated to the starter function and the other is dedicated to the service function. Only one alternator charges the two batteries with a separation device between the two electrical circuits. The starter battery is located in the engine compartment while the service battery is located at the rear of the car. From the analysis of new requirements, battery designs have been optimized regarding the two types of functions: (i) a small battery with high specific power for the starting function; for this function a flooded battery with lead-calcium alloy grids and thin plates is proposed; (ii) for the service function, modified sealed gas-recombinant batteries with cycling and deep-discharge ability have been developed. The various advantages of the dual-concept are studied in terms of starting reliability, battery weight, and voltage supply. The operating conditions of the system and several dual electrical architectures have also been studied in the laboratory and the car. The feasibility of the concept is proved.

  7. Optimization of a Vanadium Redox Flow Battery with Hydrogen generation

    OpenAIRE

    Wrang, Daniel

    2016-01-01

    We consider the modelling and optimal control of energy storage systems, in this study a Vanadium Redox Flow Battery. Such a battery can be introduced in the electrical grid to be charged when demand is low and discharged when demand is high, increasing the overall efficiency of the network while reducing costs and emission of greenhouse gases. The model of the battery proposed in this study is less complex than the majority of models on batteries and energy storage systems found in literatur...

  8. Optimization of a sequence of reactors

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    1991-01-01

    Concerns the optimal production of sulphuric acid in a sequence of reactors. Using a suitable approximation to the objective function, this problem can easily be solved using the maximum principle. A numerical example documents the applicability of the suggested approach...

  9. Optimization of batteries for plug-in hybrid electric vehicles

    Science.gov (United States)

    English, Jeffrey Robb

    This thesis presents a method to quickly determine the optimal battery for an electric vehicle given a set of vehicle characteristics and desired performance metrics. The model is based on four independent design variables: cell count, cell capacity, state-of-charge window, and battery chemistry. Performance is measured in seven categories: cost, all-electric range, maximum speed, acceleration, battery lifetime, lifetime greenhouse gas emissions, and charging time. The performance of each battery is weighted according to a user-defined objective function to determine its overall fitness. The model is informed by a series of battery tests performed on scaled-down battery samples. Seven battery chemistries were tested for capacity at different discharge rates, maximum output power at different charge levels, and performance in a real-world automotive duty cycle. The results of these tests enable a prediction of the performance of the battery in an automobile. Testing was performed at both room temperature and low temperature to investigate the effects of battery temperature on operation. The testing highlighted differences in behavior between lithium, nickel, and lead based batteries. Battery performance decreased with temperature across all samples with the largest effect on nickel-based chemistries. Output power also decreased with lead acid batteries being the least affected by temperature. Lithium-ion batteries were found to be highly efficient (>95%) under a vehicular duty cycle; nickel and lead batteries have greater losses. Low temperatures hindered battery performance and resulted in accelerated failure in several samples. Lead acid, lead tin, and lithium nickel alloy batteries were unable to complete the low temperature testing regime without losing significant capacity and power capability. This is a concern for their applicability in electric vehicles intended for cold climates which have to maintain battery temperature during long periods of inactivity

  10. Electrochemical model based charge optimization for lithium-ion batteries

    Science.gov (United States)

    Pramanik, Sourav; Anwar, Sohel

    2016-05-01

    In this paper, we propose the design of a novel optimal strategy for charging the lithium-ion battery based on electrochemical battery model that is aimed at improved performance. A performance index that aims at minimizing the charging effort along with a minimum deviation from the rated maximum thresholds for cell temperature and charging current has been defined. The method proposed in this paper aims at achieving a faster charging rate while maintaining safe limits for various battery parameters. Safe operation of the battery is achieved by including the battery bulk temperature as a control component in the performance index which is of critical importance for electric vehicles. Another important aspect of the performance objective proposed here is the efficiency of the algorithm that would allow higher charging rates without compromising the internal electrochemical kinetics of the battery which would prevent abusive conditions, thereby improving the long term durability. A more realistic model, based on battery electro-chemistry has been used for the design of the optimal algorithm as opposed to the conventional equivalent circuit models. To solve the optimization problem, Pontryagins principle has been used which is very effective for constrained optimization problems with both state and input constraints. Simulation results show that the proposed optimal charging algorithm is capable of shortening the charging time of a lithium ion cell while maintaining the temperature constraint when compared with the standard constant current charging. The designed method also maintains the internal states within limits that can avoid abusive operating conditions.

  11. Optimal energy management strategy for battery powered electric vehicles

    International Nuclear Information System (INIS)

    Highlights: • The power usage for battery-powered electrical vehicles with in-wheel motors is maximized. • The battery and motor dynamics are examined emphasized on the power conversion and utilization. • The optimal control strategy is derived and verified by simulations. • An analytic expression of the optimal operating point is obtained. - Abstract: Due to limited energy density of batteries, energy management has always played a critical role in improving the overall energy efficiency of electric vehicles. In this paper, a key issue within the energy management problem will be carefully tackled, i.e., maximizing the power usage of batteries for battery-powered electrical vehicles with in-wheel motors. To this end, the battery and motor dynamics will be thoroughly examined with particular emphasis on the power conversion and power utilization. The optimal control strategy will then be derived based on the analysis. One significant contribution of this work is that an analytic expression for the optimal operating point in terms of the component and environment parameters can be obtained. Owing to this finding, the derived control strategy is also rendered a simple structure for real-time implementation. Simulation results demonstrate that the proposed strategy works both adaptively and robustly under different driving scenarios

  12. Optimal power flow management for distributed energy resources with batteries

    International Nuclear Information System (INIS)

    Highlights: • A PV-diesel-battery hybrid system is proposed. • Model minimizes fuel and battery wear costs. • Power flows are analysed in a 24-h period. • Results provide a practical platform for decision making. - Abstract: This paper presents an optimal energy management model of a solar photovoltaic-diesel-battery hybrid power supply system for off-grid applications. The aim is to meet the load demand completely while satisfying the system constraints. The proposed model minimizes fuel and battery wear costs and finds the optimal power flow, taking into account photovoltaic power availability, battery bank state of charge and load power demand. The optimal solutions are compared for cases when the objectives are weighted equally and when a larger weight is assigned to battery wear. A considerable increase in system operational cost is observed in the latter case owing to the increased usage of the diesel generator. The results are important for decision makers, as they depict the optimal decisions considered in the presence of trade-offs between conflicting objectives

  13. Multivariable optimization of fusion reactor blankets

    International Nuclear Information System (INIS)

    The optimization problem consists of four key elements: a figure of merit for the reactor, a technique for estimating the neutronic performance of the blanket as a function of the design variables, constraints on the design variables and neutronic performance, and a method for optimizing the figure of merit subject to the constraints. The first reactor concept investigated uses a liquid lithium blanket for breeding tritium and a steel blanket to increase the fusion energy multiplication factor. The capital cost per unit of net electric power produced is minimized subject to constraints on the tritium breeding ratio and radiation damage rate. The optimal design has a 91-cm-thick lithium blanket denatured to 0.1% 6Li. The second reactor concept investigated uses a BeO neutron multiplier and a LiAlO2 breeding blanket. The total blanket thickness is minimized subject to constraints on the tritium breeding ratio, the total neutron leakage, and the heat generation rate in aluminum support tendons. The optimal design consists of a 4.2-cm-thick BeO multiplier and 42-cm-thick LiAlO2 breeding blanket enriched to 34% 6Li

  14. Optimally moderated nuclear fission reactor and fuel source therefor

    Science.gov (United States)

    Ougouag, Abderrafi M.; Terry, William K.; Gougar, Hans D.

    2008-07-22

    An improved nuclear fission reactor of the continuous fueling type involves determining an asymptotic equilibrium state for the nuclear fission reactor and providing the reactor with a moderator-to-fuel ratio that is optimally moderated for the asymptotic equilibrium state of the nuclear fission reactor; the fuel-to-moderator ratio allowing the nuclear fission reactor to be substantially continuously operated in an optimally moderated state.

  15. Scaling behavior of optimally structured catalytic microfluidic reactors

    DEFF Research Database (Denmark)

    Okkels, Fridolin; Bruus, Henrik

    2007-01-01

    In this study of catalytic microfluidic reactors we show that, when optimally structured, these reactors share underlying scaling properties. The scaling is predicted theoretically and verified numerically. Furthermore, we show how to increase the reaction rate significantly by distributing the...

  16. Optimal bidding strategy of battery storage in power markets considering performance based regulation and battery cycle life

    DEFF Research Database (Denmark)

    He, Guannan; Chen, Qixin; Kang, Chongqing;

    2015-01-01

    Large-scale battery storage will become an essential part of the future smart grid. This paper investigates the optimal bidding strategy for battery storage in power markets. Battery storage could increase its profitability by providing fast regulation service under a performance-based regulation...... mechanism, which better exploits a battery’s fast ramping capability. However, battery life might be decreased by frequent charge–discharge cycling, especially when providing fast regulation service. It is profitable for battery storage to extend its service life by limiting its operational strategy to some...... degree. Thus, we incorporate a battery cycle life model into a profit maximization model to determine the optimal bids in day-ahead energy, spinning reserve, and regulation markets. Then a decomposed online calculation method to compute cycle life under different operational strategies is proposed...

  17. Fast reactor parameter optimization taking into account changes in fuel charge type during reactor operation time

    International Nuclear Information System (INIS)

    The formulation and solution of optimization problem for parameters determining the layout of the central part of sodium cooled power reactor taking into account possible changes in fuel charge type during reactor operation time are performed. The losses under change of fuel composition type for two reactor modifications providing for minimum doubling time for oxide and carbide fuels respectively, are estimated

  18. Flow Simulation and Optimization of Plasma Reactors for Coal Gasification

    Institute of Scientific and Technical Information of China (English)

    冀春俊; 张英姿; 马腾才

    2003-01-01

    This paper reports a 3-d numerical simulation system to analyze the complicatedflow in plasma reactors for coal gasification, which involve complex chemical reaction, two-phaseflow and plasma effect. On the basis of analytic results, the distribution of the density, tempera-ture and components' concentration are obtained and a different plasma reactor configuration isproposed to optimize the flow parameters. The numerical simulation results show an improvedconversion ratio of the coal gasification. Different kinds of chemical reaction models are used tosimulate the complex flow inside the reactor. It can be concluded that the numerical simulationsystem can be very useful for the design and optimization of the plasma reactor.

  19. Optimization of methanol yield from a Lurgi reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L.; Jiang, Q.; Song, Z. [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing (China); Posarac, D. [Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver (Canada)

    2011-05-15

    Methanol is an important chemical with the potential to become an alternative fuel. An optimization study was performed for a Lurgi methanol synthesis reactor using the commercial process simulator Aspen Plus. The optimization routine is coupled with a steady-state model of the methanol synthesis reactor. Syngas inlet temperature, steam drum pressure, and cooling water volumetric flow rate were optimized so that methanol production in the reactor outlet was maximized. The methanol yield increased by 7.04 %. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Fuel shuffling optimization for the Delft research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Geemert, R. van; Hoogenboom, J.E.; Gibcus, H.P.M. [Delft Univ. of Technology, Interfaculty Reactor Inst., Delft (Netherlands); Quist, A.J. [Delft Univ., Fac. of Applied Mathematics and Informatics, Delft (Netherlands)

    1997-07-01

    A fuel shuffling optimization procedure is proposed for the Hoger Onderwijs Reactor (HOR) in Delft, the Netherlands, a 2 MWth swimming-pool type research reactor. In order to cope with the fluctuatory behaviour of objective functions in loading pattern optimization, the proposed cyclic permutation optimization procedure features a gradual transition from global to local search behaviour via the introduction of stochastic tests for the number of fuel assemblies involved in a cyclic permutation. The possible objectives and the safety and operation constraints, as well as the optimization procedure, are discussed, followed by some optimization results for the HOR. (author)

  1. Optimization studies on a Fe/Cr redox flow battery

    Science.gov (United States)

    Lopez-Atalaya, M.; Codina, G.; Perez, J. R.; Vazquez, J. L.; Aldaz, A.

    The performance of a Fe/Cr redox flow battery which operates in bipolar mode is described. The optimization studies on electrolyte composition, temperature and membrane type are presented. These studies have achieved a coulombic efficiency of 97% and an energy efficiency of 73% for an electrolyte composition of 2.3 M HCl + 1.25 M FeCl 2 + 1.25 M CrCl 3, working at 44 °C with a current density of 40 mA/cm 2 and using the Nafion 117 membrane. A maximum discharge power density of 73 mW/cm 2 has been obtained.

  2. Optimal energy storing and selling in continuous time stochastic multi-battery setting

    OpenAIRE

    Dokuchaev, Nikolai

    2015-01-01

    We consider the problem of optimal energy storing and dispatching for a grid-connected energy producer with battery energy storage system (BESS). We suggests an optimal operating algorithm that helps to increase the income given limited storage capacity and unpredictable fluctuations of the production rate and selling prices. In addition, the operating algorithm takes into account preferable regimes for charging and discharging the batteries, this can help to prolong the battery life. The pro...

  3. Optimized anion exchange membranes for vanadium redox flow batteries.

    Science.gov (United States)

    Chen, Dongyang; Hickner, Michael A; Agar, Ertan; Kumbur, E Caglan

    2013-08-14

    In order to understand the properties of low vanadium permeability anion exchange membranes for vanadium redox flow batteries (VRFBs), quaternary ammonium functionalized Radel (QA-Radel) membranes with three ion exchange capacities (IECs) from 1.7 to 2.4 mequiv g(-1) were synthesized and 55-60 μm thick membrane samples were evaluated for their transport properties and in-cell battery performance. The ionic conductivity and vanadium permeability of the membranes were investigated and correlated to the battery performance through measurements of Coulombic efficiency, voltage efficiency and energy efficiency in single cell tests, and capacity fade during cycling. Increasing the IEC of the QA-Radel membranes increased both the ionic conductivity and VO(2+) permeability. The 1.7 mequiv g(-1) IEC QA-Radel had the highest Coulombic efficiency and best cycling capacity maintenance in the VRFB, while the cell's voltage efficiency was limited by the membrane's low ionic conductivity. Increasing the IEC resulted in higher voltage efficiency for the 2.0 and 2.4 mequiv g(-1) samples, but the cells with these membranes displayed reduced Coulombic efficiency and faster capacity fade. The QA-Radel with an IEC of 2.0 mequiv g(-1) had the best balance of ionic conductivity and VO(2+) permeability, achieving a maximum power density of 218 mW cm(-2) which was higher than the maximum power density of a VRFB assembled with a Nafion N212 membrane in our system. While anion exchange membranes are under study for a variety of VRFB applications, this work demonstrates that the material parameters must be optimized to obtain the maximum cell performance. PMID:23799776

  4. Optimized anion exchange membranes for vanadium redox flow batteries.

    Science.gov (United States)

    Chen, Dongyang; Hickner, Michael A; Agar, Ertan; Kumbur, E Caglan

    2013-08-14

    In order to understand the properties of low vanadium permeability anion exchange membranes for vanadium redox flow batteries (VRFBs), quaternary ammonium functionalized Radel (QA-Radel) membranes with three ion exchange capacities (IECs) from 1.7 to 2.4 mequiv g(-1) were synthesized and 55-60 μm thick membrane samples were evaluated for their transport properties and in-cell battery performance. The ionic conductivity and vanadium permeability of the membranes were investigated and correlated to the battery performance through measurements of Coulombic efficiency, voltage efficiency and energy efficiency in single cell tests, and capacity fade during cycling. Increasing the IEC of the QA-Radel membranes increased both the ionic conductivity and VO(2+) permeability. The 1.7 mequiv g(-1) IEC QA-Radel had the highest Coulombic efficiency and best cycling capacity maintenance in the VRFB, while the cell's voltage efficiency was limited by the membrane's low ionic conductivity. Increasing the IEC resulted in higher voltage efficiency for the 2.0 and 2.4 mequiv g(-1) samples, but the cells with these membranes displayed reduced Coulombic efficiency and faster capacity fade. The QA-Radel with an IEC of 2.0 mequiv g(-1) had the best balance of ionic conductivity and VO(2+) permeability, achieving a maximum power density of 218 mW cm(-2) which was higher than the maximum power density of a VRFB assembled with a Nafion N212 membrane in our system. While anion exchange membranes are under study for a variety of VRFB applications, this work demonstrates that the material parameters must be optimized to obtain the maximum cell performance.

  5. An Optimal Operating Strategy for Battery Life Cycle Costs in Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Yinghua Han

    2014-01-01

    Full Text Available Impact on petroleum based vehicles on the environment, cost, and availability of fuel has led to an increased interest in electric vehicle as a means of transportation. Battery is a major component in an electric vehicle. Economic viability of these vehicles depends on the availability of cost-effective batteries. This paper presents a generalized formulation for determining the optimal operating strategy and cost optimization for battery. Assume that the deterioration of the battery is stochastic. Under the assumptions, the proposed operating strategy for battery is formulated as a nonlinear optimization problem considering reliability and failure number. And an explicit expression of the average cost rate is derived for battery lifetime. Results show that the proposed operating strategy enhances the availability and reliability at a low cost.

  6. The nuclear battery: a very small reactor power supply for remote locations; Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Kozier, K.S. (Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.)

    1992-08-01

    The Nuclear Battery is a small reactor power supply being developed by Atomic Energy of Canada Limited for use in locations that are remote from utility grids and natural gas pipelines. Key technical features of the Nuclear Battery reactor core include a heat-pipe primary heat transport system, graphite neutron moderator, low enriched uranium TRISO coated-particle fuel and the use of burnable poisons for long-term reactivity control. An external secondary heat transport system extracts useful heat energy that may be converted into electricity in an organic Rankine cycle engine, or used to produce high-pressure steam. The reference design is capable of producing about 2400 kW(t) (about 500 kW(e) net) for 15 full-power years without refuelling. (orig.).

  7. The nuclear battery: a very small reactor power supply for remote locations

    Energy Technology Data Exchange (ETDEWEB)

    Kozier, K.S. (Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Nuclear Research Establishment)

    The Nuclear Battery is a small reactor power supply being developed by Atomic Energy of Canada Limited for use in locations that are remote from utility grids and natural gas pipelines. Key technical features of the Nuclear Battery reactor core include a heat-pipe primary heat transport system, graphite neutron moderator, low-enriched uranium TRISO coated-particle fuel, and the use of burnable poisons for long-term reactivity control. An external secondary heat transport system extracts useful heat energy that may be converted into electricity in an organic Rankine cycle engine, or used to produce a high-pressure steam. The reference design is capable of producing about 2400 kW(t) (about 600 kW(e) net) for 15 full-power years without refueling. (author).

  8. Optimization of Charging Current and SOH Estimation for Lead Acid Batteries

    Directory of Open Access Journals (Sweden)

    Amin Rezaei Pish Robat

    2012-02-01

    Full Text Available In this paper a new model-based approach is used to optimize the charging current of lead acid batteries for use in hybrid electric. The used model is a dynamical nonlinear model and so steepest descent, as a nonlinear optimization technique, is used to design the desired current profile. To verify the results, Unscented Kalman Filter is used to estimate battery capacity as a criterion of the state of health of the battery. Simulation results show that in comparison with multi level charging current, the proposed approach improves the state of health of the battery, up to 2.5% in the first 100 charge/discharge cycle

  9. Fast-power-reactor optimization by the game theory

    International Nuclear Information System (INIS)

    In the first stage of the use of fast breeder reactor - because fissile-material amounts are small - we are interested in fast breeder reactors which achieve minimum fissile-material mass, with maximum power. This problem shows a two-matrix-game structure. First, we determine a competive-game solution and second, a cooperative-game solution, obtaining in this way the optimum distribution of the fissile and fertile materials in the multizone fast reactors. Another optimization problem which is solved in this paper is finding the reactor structure for which the power non-uniformity factor and the flux non-uniformity factor are minimum. This is, also, a mathematical two-matrix game and it is solved as above. The two optimization problems have different solutions. (author)

  10. Optimal Battery Utilization Over Lifetime for Parallel Hybrid Electric Vehicle to Maximize Fuel Economy

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Chinmaya; Naghshtabrizi, Payam; Verma, Rajeev; Tang, Zhijun; Smith, Kandler; Shi, Ying

    2016-08-01

    This paper presents a control strategy to maximize fuel economy of a parallel hybrid electric vehicle over a target life of the battery. Many approaches to maximizing fuel economy of parallel hybrid electric vehicle do not consider the effect of control strategy on the life of the battery. This leads to an oversized and underutilized battery. There is a trade-off between how aggressively to use and 'consume' the battery versus to use the engine and consume fuel. The proposed approach addresses this trade-off by exploiting the differences in the fast dynamics of vehicle power management and slow dynamics of battery aging. The control strategy is separated into two parts, (1) Predictive Battery Management (PBM), and (2) Predictive Power Management (PPM). PBM is the higher level control with slow update rate, e.g. once per month, responsible for generating optimal set points for PPM. The considered set points in this paper are the battery power limits and State Of Charge (SOC). The problem of finding the optimal set points over the target battery life that minimize engine fuel consumption is solved using dynamic programming. PPM is the lower level control with high update rate, e.g. a second, responsible for generating the optimal HEV energy management controls and is implemented using model predictive control approach. The PPM objective is to find the engine and battery power commands to achieve the best fuel economy given the battery power and SOC constraints imposed by PBM. Simulation results with a medium duty commercial hybrid electric vehicle and the proposed two-level hierarchical control strategy show that the HEV fuel economy is maximized while meeting a specified target battery life. On the other hand, the optimal unconstrained control strategy achieves marginally higher fuel economy, but fails to meet the target battery life.

  11. Genetic algorithms applied to nuclear reactor design optimization

    International Nuclear Information System (INIS)

    A genetic algorithm is a powerful search technique that simulates natural evolution in order to fit a population of computational structures to the solution of an optimization problem. This technique presents several advantages over classical ones such as linear programming based techniques, often used in nuclear engineering optimization problems. However, genetic algorithms demand some extra computational cost. Nowadays, due to the fast computers available, the use of genetic algorithms has increased and its practical application has become a reality. In nuclear engineering there are many difficult optimization problems related to nuclear reactor design. Genetic algorithm is a suitable technique to face such kind of problems. This chapter presents applications of genetic algorithms for nuclear reactor core design optimization. A genetic algorithm has been designed to optimize the nuclear reactor cell parameters, such as array pitch, isotopic enrichment, dimensions and cells materials. Some advantages of this genetic algorithm implementation over a classical method based on linear programming are revealed through the application of both techniques to a simple optimization problem. In order to emphasize the suitability of genetic algorithms for design optimization, the technique was successfully applied to a more complex problem, where the classical method is not suitable. Results and comments about the applications are also presented. (orig.)

  12. Large-Scale Optimization of Complex Separator and Reactor Networks

    OpenAIRE

    Ghougassian, Paul Gougas

    2013-01-01

    The generation of globally optimal designs which can minimize capital and/or operating cost expenditures is a highly sought after objective within the chemical industry. A methodology which can systematically generate such globally optimal solutions to objective functions commonly encountered in the chemical industry is the IDEAS framework. The IDEAS framework decomposes a process network into an operator, OP network, where the unit operations (reactors, distillation columns, heat exchangers,...

  13. Optimization of ultra-long cycle fast reactor core

    International Nuclear Information System (INIS)

    An optimization of an ultra-long cycle fast reactor (UCFR) design with a power rate of 1000 MW (electric), UCFR-1000, has been performed to increase the safety of UCFR. Firstly, geometric optimization has been performed to decrease its peaking factors so that the peak temperatures measured by thermal hydraulic feedback are within the limit of design basis event (DBE). Secondly, fuel composition optimization has been performed by adopting Pressurized Water Reactor (PWR) spent fuel as a blanket material instead of natural uranium. Lastly, a small-size UCFR with a power rate of 100 MWe, UCFR-100, has been proposed for developing a short term deployable nuclear reactor. The major optimization process for UCFR-100 is decreasing maximum neutron flux and fast neutron fluence. The optimized UCFR-1000 has been enlarged radially and shortened axially from the initial UCFR design and this modification makes the burning speed of active core movement slower. It has been confirmed that a full-power operation of 60 years without refueling is feasible for both UCFR-1000 and UCFR-100 core designs by a breed-and-burn strategy. By the design optimization study, the reductions of maximum neutron flux, fast neutron fluence, and axial power peaking have been achieved, which are favorable for the safety of the UCFR. (author)

  14. Prediction Model of Battery State of Charge and Control Parameter Optimization for Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2015-07-01

    Full Text Available This paper presents the construction of a battery state of charge (SOC prediction model and the optimization method of the said model to appropriately control the number of parameters in compliance with the SOC as the battery output objectives. Research Centre for Electrical Power and Mechatronics, Indonesian Institute of Sciences has tested its electric vehicle research prototype on the road, monitoring its voltage, current, temperature, time, vehicle velocity, motor speed, and SOC during the operation. Using this experimental data, the prediction model of battery SOC was built. Stepwise method considering multicollinearity was able to efficiently develops the battery prediction model that describes the multiple control parameters in relation to the characteristic values such as SOC. It was demonstrated that particle swarm optimization (PSO succesfully and efficiently calculated optimal control parameters to optimize evaluation item such as SOC based on the model.

  15. Optimal input shaping for Fisher identifiability of control-oriented lithium-ion battery models

    Science.gov (United States)

    Rothenberger, Michael J.

    This dissertation examines the fundamental challenge of optimally shaping input trajectories to maximize parameter identifiability of control-oriented lithium-ion battery models. Identifiability is a property from information theory that determines the solvability of parameter estimation for mathematical models using input-output measurements. This dissertation creates a framework that exploits the Fisher information metric to quantify the level of battery parameter identifiability, optimizes this metric through input shaping, and facilitates faster and more accurate estimation. The popularity of lithium-ion batteries is growing significantly in the energy storage domain, especially for stationary and transportation applications. While these cells have excellent power and energy densities, they are plagued with safety and lifespan concerns. These concerns are often resolved in the industry through conservative current and voltage operating limits, which reduce the overall performance and still lack robustness in detecting catastrophic failure modes. New advances in automotive battery management systems mitigate these challenges through the incorporation of model-based control to increase performance, safety, and lifespan. To achieve these goals, model-based control requires accurate parameterization of the battery model. While many groups in the literature study a variety of methods to perform battery parameter estimation, a fundamental issue of poor parameter identifiability remains apparent for lithium-ion battery models. This fundamental challenge of battery identifiability is studied extensively in the literature, and some groups are even approaching the problem of improving the ability to estimate the model parameters. The first approach is to add additional sensors to the battery to gain more information that is used for estimation. The other main approach is to shape the input trajectories to increase the amount of information that can be gained from input

  16. Geometric-Process-Based Battery Management Optimizing Policy for the Electric Bus

    Directory of Open Access Journals (Sweden)

    Yan Li

    2015-01-01

    Full Text Available With the rapid development of the electric vehicle industry and promotive policies worldwide, the electric bus (E-bus has been adopted in many major cities around the world. One of the most important factors that restrain the widespread application of the E-bus is the high operating cost due to the deficient battery management. This paper proposes a geometric-process-based (GP-based battery management optimizing policy which aims to minimize the average cost of the operation on the premise of meeting the required sufficient battery availability. Considering the deterioration of the battery after repeated charging and discharging, this paper constructs the model of the operation of the E-bus battery as a geometric process, and the premaintenance time has been considered with the failure repairment time to enhance the GP-based battery operation model considering the battery cannot be as good as new after the two processes. The computer simulation is carried out by adopting the proposed optimizing policy, and the result verifies the effectiveness of the policy, denoting its significant performance on the application of the E-bus battery management.

  17. Optimal management of stationary lithium-ion battery system in electricity distribution grids

    Science.gov (United States)

    Purvins, Arturs; Sumner, Mark

    2013-11-01

    The present article proposes an optimal battery system management model in distribution grids for stationary applications. The main purpose of the management model is to maximise the utilisation of distributed renewable energy resources in distribution grids, preventing situations of reverse power flow in the distribution transformer. Secondly, battery management ensures efficient battery utilisation: charging at off-peak prices and discharging at peak prices when possible. This gives the battery system a shorter payback time. Management of the system requires predictions of residual distribution grid demand (i.e. demand minus renewable energy generation) and electricity price curves (e.g. for 24 h in advance). Results of a hypothetical study in Great Britain in 2020 show that the battery can contribute significantly to storing renewable energy surplus in distribution grids while being highly utilised. In a distribution grid with 25 households and an installed 8.9 kW wind turbine, a battery system with rated power of 8.9 kW and battery capacity of 100 kWh can store 7 MWh of 8 MWh wind energy surplus annually. Annual battery utilisation reaches 235 cycles in per unit values, where one unit is a full charge-depleting cycle depth of a new battery (80% of 100 kWh).

  18. Development and Optimization of Modular Hybrid Plasma Reactor

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    2013-01-02

    INL developed a bench–scale, modular hybrid plasma system for gas-phase nanomaterials synthesis. The system was optimized for WO{sub 3} nanoparticle production and scale-model projection to a 300 kW pilot system. During the course of technology development, many modifications were made to the system to resolve technical issues that surfaced and also to improve performance. All project tasks were completed except two optimization subtasks. Researchers were unable to complete these two subtasks, a four-hour and an eight-hour continuous powder production run at 1 lb/hr powder-feeding rate, due to major technical issues developed with the reactor system. The 4-hour run was attempted twice, and on both occasions, the run was terminated prematurely. The termination was due to (1) heavy material condensation on the modular electrodes, which led to system operational instability, and (2) pressure buildup in the reactor due to powder clogging of the exhaust gas and product transfer line. The modular electrode for the plasma system was significantly redesigned to address the material condensation problem on the electrodes. However, the cause for product powder clogging of the exhaust gas and product transfer line led to a pressure build up in the reactor that was undetected. Fabrication of the redesigned modular electrodes and additional components was completed near the end of the project life. However, insufficient resource was available to perform tests to evaluate the performance of the new modifications. More development work would be needed to resolve these problems prior to scaling. The technology demonstrated a surprising capability of synthesizing a single phase of meta-stable {delta}- Al{sub 2}O{sub 3} from pure {alpha}-phase large Al{sub 2}O{sub 3} powder. The formation of {delta} -Al{sub 2}O{sub 3} was surprising because this phase is meta-stable and only formed between 973–1073 K, and {delta} -Al{sub 2}O{sub 3} is very difficult to synthesize as a single

  19. Modeling and Optimal Control of a Redox Flow Battery

    OpenAIRE

    Wrang, Daniel; Faulwasser, Timm; Billeter, Julien; Amstutz, Véronique; Vrubel, Heron; Battistel, Alberto; Girault, Hubert; Bonvin, Dominique

    2016-01-01

    Vanadium Redox Flow Batteries (VRFB) can be used as energy storage device, for example to account for wind or solar power fluctuations. In VRFBs charge is stored in two tanks containing two different vanadium solutions. This approach decouples the storage capacity and the power supply which is dependent only on the number and size of the cells [1]. A control specific model of a VRFB is proposed, which captures the essential dynamic properties of the battery while ignoring all fluid mechanica...

  20. Chemical looping combustion in a rotating bed reactor--finding optimal process conditions for prototype reactor.

    Science.gov (United States)

    Håkonsen, Silje Fosse; Blom, Richard

    2011-11-15

    A lab-scale rotating bed reactor for chemical looping combustion has been designed, constructed, and tested using a CuO/Al(2)O(3) oxygen carrier and methane as fuel. Process parameters such as bed rotating frequency, gas flows, and reactor temperature have been varied to find optimal performance of the prototype reactor. Around 90% CH(4) conversion and >90% CO(2) capture efficiency based on converted methane have been obtained. Stable operation has been accomplished over several hours, and also--stable operation can be regained after intentionally running into unstable conditions. Relatively high gas velocities are used to avoid fully reduced oxygen carrier in part of the bed. Potential CO(2) purity obtained is in the range 30 to 65%--mostly due to air slippage from the air sector--which seems to be the major drawback of the prototype reactor design. Considering the prototype nature of the first version of the rotating reactor setup, it is believed that significant improvements can be made to further avoid gas mixing in future modified and up-scaled reactor versions.

  1. Applications of prognostics for maintenance optimization of research reactors

    International Nuclear Information System (INIS)

    The optimization of operation especially maintenance and surveillance of various components and systems of research reactors using prognostic have been emphasized in this study to save cost and time while keeping safety and reliability high. This study is focused on the research reactors due to margin of cost competitiveness and regulation. The feasibility study has been performed in order to find the potential candidates from research reactors, on which prognostic can be implemented. System and components has been classified into category I and category II, based on the nature of working during the operation of research reactor. The systems of category I are those which, either full or part of them, remain in working condition during normal operation of a research reactor. For instance, instrumentation and control components of safety, protection and monitoring systems belong to this category. Contrary to this, the systems which remain standby during normal operation and start operation on safety signals are grouped in category II. Motor operated valves, pumps of emergency system and vital power system are well suited examples. The online and offline prognostics have been proposed as a work approach for category I and category II systems respectively. (author)

  2. Shape optimization of a sodium cooled fast reactor

    Science.gov (United States)

    Schmitt, Damien; Allaire, Grégoire; Pantz, Olivier; Pozin, Nicolas

    2014-06-01

    Traditional designs of sodium cooled fast reactors have a positive sodium expansion feedback. During a loss of flow transient without scram, sodium heating and boiling thus insert a positive reactivity and prevents the power from decreasing. Recent studies led at CEA, AREVA and EDF show that cores with complex geometries can feature a very low or even a negative sodium void worth.(1, 2) Usual optimization methods for core conception are based on a parametric description of a given core design(3).(4) New core concepts and shapes can then only be found by hand. Shape optimization methods have proven very efficient in the conception of optimal structures under thermal or mechanical constraints.(5, 6) First studies show that these methods could be applied to sodium cooled core conception.(7) In this paper, a shape optimization method is applied to the conception of a sodium cooled fast reactor core with low sodium void worth. An objective function to be minimized is defined. It includes the reactivity change induced by a 1% sodium density decrease. The optimization variable is a displacement field changing the core geometry from one shape to another. Additionally, a parametric optimization of the plutonium content distribution of the core is made, so as to ensure that the core is kept critical, and that the power shape is flat enough. The final shape obtained must then be adjusted to a get realistic core layout. Its caracteristics can be checked with reference neutronic codes such as ERANOS. Thanks to this method, new shapes of reactor cores could be inferred, and lead to new design ideas.

  3. A supercomputing application for reactors core design and optimization

    International Nuclear Information System (INIS)

    Advanced nuclear reactor designs are often intuition-driven processes where designers first develop or use simplified simulation tools for each physical phenomenon involved. Through the project development, complexity in each discipline increases and implementation of chaining/coupling capabilities adapted to supercomputing optimization process are often postponed to a further step so that task gets increasingly challenging. In the context of renewal in reactor designs, project of first realization are often run in parallel with advanced design although very dependant on final options. As a consequence, the development of tools to globally assess/optimize reactor core features, with the on-going design methods accuracy, is needed. This should be possible within reasonable simulation time and without advanced computer skills needed at project management scale. Also, these tools should be ready to easily cope with modeling progresses in each discipline through project life-time. An early stage development of multi-physics package adapted to supercomputing is presented. The URANIE platform, developed at CEA and based on the Data Analysis Framework ROOT, is very well adapted to this approach. It allows diversified sampling techniques (SRS, LHS, qMC), fitting tools (neuronal networks...) and optimization techniques (genetic algorithm). Also data-base management and visualization are made very easy. In this paper, we'll present the various implementing steps of this core physics tool where neutronics, thermo-hydraulics, and fuel mechanics codes are run simultaneously. A relevant example of optimization of nuclear reactor safety characteristics will be presented. Also, flexibility of URANIE tool will be illustrated with the presentation of several approaches to improve Pareto front quality. (author)

  4. Parameter estimation and optimal experimental design in flow reactors

    OpenAIRE

    Carraro, Thomas

    2005-01-01

    In this work we present numerical techniques, based on the finite element method, for the simulation of reactive flows in a chemical flow reactor as well as for the identification of the kinetic of the reactions using measurements of observable quantities. We present the case of a real experiment in which the reaction rate is estimated by means of concentration measurements. We introduce methods for the optimal experimental design of experiments in the context of reactive flows modeled by par...

  5. Optimization of Moving Bed Biofilm ReactorUsing Taguchi Method

    Directory of Open Access Journals (Sweden)

    R Nabizadeh Nodehi

    2009-07-01

    Full Text Available "n "nBackgrounds and Objectives: in recent years, mobile bed biological reactors have been used progressively for municipal and industrial wastewaters treatment. Dissented experiment is a trial that significant changes will accrue for influent variables in the process, and generally used for identification of the effective factors and optimization of the process. The scope of this study was determination of the optimized conditions for the MBBR process by using of Taguchi method. "nMaterials and Methods: Reactor start up was done by using of the recycled activated sludge from Ahwaz wastewater treatment plant. After that and passing the acclimation period, with hydraulic residence time equal to 9 hours matched for 1000, 2000 and 3000 mg/l based on COD respectively, for optimization determination of the acclimated microbial growth, the variables change (pH, nitrogen source, chemical oxygen demand and salinity were determined in 9 steps, and all of the results were analyzed by Qualitek -4 (w32b."nResults:In this study, organic load removal based on COD was 97% and best optimized condition for MBBR were (inf. COD=1000 mg/l, pH= 8, salinity = 5% and the Nitrogen source= NH4CL"nConclusion: Based on our finding, we may conclude that Taguchi method is on of the appropriate procedure in determination the optimized condition for increasing removal efficiency of MBBR.

  6. Temperature Field Analysis and Thermal Dissipation Structure Optimization of Lithium-ion Battery Pack in PEVs

    Directory of Open Access Journals (Sweden)

    Hu Jianjun

    2014-01-01

    Full Text Available Aimed to achieve good thermal stability of lithium batteries in electric vehicles under the conditions of high-power. This study established a three-dimensional, transient heat dissipation model for Lithium-ion battery package in the three-dimensional Cartesian coordinate system based on theoretical knowledge of thermodynamics and heat transfer. With the help of the numerical simulation theoretical of CFD, the flow and temperature field of force air cooling Lithium-ion battery pack was simulated with the heat source obtained from dynamic performance simulations of Pure Electric Vehicles (PEVs under 15% climbing conditions. For the issues of high temperature rise and large temperature difference, optimal programs to improve the cooling effect of Lithium-ion battery pack were proposed. Simulation results indicate that the optimal measures make heat dissipation well and temperature distribution uniform, which satisfies the application requirement in PEVs.

  7. Multi-objective optimal design of lithium-ion battery packs based on evolutionary algorithms

    Science.gov (United States)

    Severino, Bernardo; Gana, Felipe; Palma-Behnke, Rodrigo; Estévez, Pablo A.; Calderón-Muñoz, Williams R.; Orchard, Marcos E.; Reyes, Jorge; Cortés, Marcelo

    2014-12-01

    Lithium-battery energy storage systems (LiBESS) are increasingly being used on electric mobility and stationary applications. Despite its increasing use and improvements of the technology there are still challenges associated with cost reduction, increasing lifetime and capacity, and higher safety. A correct battery thermal management system (BTMS) design is critical to achieve these goals. In this paper, a general framework for obtaining optimal BTMS designs is proposed. Due to the trade-off between the BTMS's design goals and the complex modeling of thermal response inside the battery pack, this paper proposes to solve this problem using a novel Multi-Objective Particle Swarm Optimization (MOPSO) approach. A theoretical case of a module with 6 cells and a real case of a pack used in a Solar Race Car are presented. The results show the capabilities of the proposal methodology, in which improved designs for battery packs are obtained.

  8. Trimode Power Converter optimizes PV, diesel and battery energy sources

    Science.gov (United States)

    Osullivan, George; Bonn, Russell; Bower, Ward

    1994-12-01

    Conservatively, there are 100,000 localities in the world waiting for the benefits that electricity can provide, and many of these are in climates where sunshine is plentiful. With these locations in mind a prototype 30 kW hybrid system has been assembled at Sandia to prove the reliability and economics of photovoltaic, diesel and battery energy sources managed by an autonomous power converter. In the Trimode Power Converter the same power parts, four IGBT's with an isolation transformer and filter components, serve as rectifier and charger to charge the battery from the diesel; as a stand-alone inverter to convert PV and battery energy to AC; and, as a parallel inverter with the diesel-generator to accommodate loads larger than the rating of the diesel. Whenever the diesel is supplying the load, an algorithm assures that the diesel is running at maximum efficiency by regulating the battery charger operating point. Given the profile of anticipated solar energy, the cost of transporting diesel fuel to a remote location and a five year projection of load demand, a method to size the PV array, battery and diesel for least cost is developed.

  9. Optimal Capacity Allocation of Large-Scale Wind-PV-Battery Units

    OpenAIRE

    2014-01-01

    An optimal capacity allocation of large-scale wind-photovoltaic- (PV-) battery units was proposed. First, an output power model was established according to meteorological conditions. Then, a wind-PV-battery unit was connected to the power grid as a power-generation unit with a rated capacity under a fixed coordinated operation strategy. Second, the utilization rate of renewable energy sources and maximum wind-PV complementation was considered and the objective function of full life cycle-net...

  10. Optimized Design and Discussion on Middle and Large CANDLE Reactors

    Directory of Open Access Journals (Sweden)

    Xiaoming Chai

    2012-08-01

    Full Text Available CANDLE (Constant Axial shape of Neutron flux, nuclide number densities and power shape During Life of Energy producing reactor reactors have been intensively researched in the last decades [1–6]. Research shows that this kind of reactor is highly economical, safe and efficiently saves resources, thus extending large scale fission nuclear energy utilization for thousands of years, benefitting the whole of society. For many developing countries with a large population and high energy demands, such as China and India, middle (1000 MWth and large (2000 MWth CANDLE fast reactors are obviously more suitable than small reactors [2]. In this paper, the middle and large CANDLE reactors are investigated with U-Pu and combined ThU-UPu fuel cycles, aiming to utilize the abundant thorium resources and optimize the radial power distribution. To achieve these design purposes, the present designs were utilized, simply dividing the core into two fuel regions in the radial direction. The less active fuel, such as thorium or natural uranium, was loaded in the inner core region and the fuel with low-level enrichment, e.g. 2.0% enriched uranium, was loaded in the outer core region. By this simple core configuration and fuel setting, rather than using a complicated method, we can obtain the desired middle and large CANDLE fast cores with reasonable core geometry and thermal hydraulic parameters that perform safely and economically; as is to be expected from CANDLE. To assist in understanding the CANDLE reactor’s attributes, analysis and discussion of the calculation results achieved are provided.

  11. Optimal Capacity Allocation of Large-Scale Wind-PV-Battery Units

    Directory of Open Access Journals (Sweden)

    Kehe Wu

    2014-01-01

    Full Text Available An optimal capacity allocation of large-scale wind-photovoltaic- (PV- battery units was proposed. First, an output power model was established according to meteorological conditions. Then, a wind-PV-battery unit was connected to the power grid as a power-generation unit with a rated capacity under a fixed coordinated operation strategy. Second, the utilization rate of renewable energy sources and maximum wind-PV complementation was considered and the objective function of full life cycle-net present cost (NPC was calculated through hybrid iteration/adaptive hybrid genetic algorithm (HIAGA. The optimal capacity ratio among wind generator, PV array, and battery device also was calculated simultaneously. A simulation was conducted based on the wind-PV-battery unit in Zhangbei, China. Results showed that a wind-PV-battery unit could effectively minimize the NPC of power-generation units under a stable grid-connected operation. Finally, the sensitivity analysis of the wind-PV-battery unit demonstrated that the optimization result was closely related to potential wind-solar resources and government support. Regions with rich wind resources and a reasonable government energy policy could improve the economic efficiency of their power-generation units.

  12. Transient cycle fuel management optimization of a pressurized water reactor

    International Nuclear Information System (INIS)

    This paper concerns with how to optimally determine enrichments of fuel assembly (FA) batches of beginning-of-life (BOL) and reload cycle cores of a pressurized water reactor (PWR) plant which runs on a multi-batch, multi-cycle fuel management scheme. As a way to determine the optimum FA enrichments, a multi-cycle, multi-objective FA loading pattern (LP) optimization problem for the transient cycle cores involving the BOL and the reload cycle cores of the PWR plant is solved by the adaptively constrained discontinuous penalty function-based (ACDPF-based) multi-objective simulated annealing (MOSA) algorithm in combination with the commercial core neutronics design code ASTRA (Advanced Static and Transient Reactor Analyzer). The applicability and the effectiveness of the ACDPF-based MOSA algorithm is examined in terms of its solution to the first three transient cycle FA LP optimization problem of Yonggwang Nuclear Unit 4 (YGN4) a PWR plant in Korea. The practicality and usefulness of the ACDPF-based MOSA algorithm as an optimizer to determine optimum enrichments of BOL and reload cycle cores are discussed. (author)

  13. The optimal control of ITU TRIGA Mark II Reactor

    International Nuclear Information System (INIS)

    In this study, optimal control of ITU TRIGA Mark-II Reactor is discussed. A new controller has been designed for ITU TRIGA Mark-II Reactor. The controller consists of main and auxiliary controllers. The form is based on Pontragyn's Maximum Principle and the latter is based on PID approach. For the desired power program, a cubic function is chosen. Integral Performance Index includes the mean square of error function and the effect of selected period on the power variation. YAVCAN2 Neutronic - Thermal -Hydraulic code is used to solve the equations, namely 11 equations, dealing with neutronic - thermal - hydraulic behavior of the reactor. For the controller design, a new code, KONTCAN, is written. In the application of the code, it is seen that the controller controls the reactor power to follow the desired power program. The overshoot value alters between 100 W and 500 W depending on the selected period. There is no undershoot. The controller rapidly increases reactivity, then decreases, after that increases it until the effect of temperature feedback is compensated. Error function varies between 0-1 kW. (author)

  14. Optimizing Battery Usage and Management for Long Life

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kandler; Shi, Ying; Wood, Eric; Pesaran, Ahmad

    2016-06-16

    This presentation discusses the impact of system design factors on battery aging and end of life. Topics include sizing of the state-of-charge operating window, cell balancing, and thermal management systems and their value in reducing pack degradation rates and cell imbalance growth over lifetime.

  15. Optimizing Battery Usage and Management for Long Life

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kandler; Shi, Ying; Wood, Eric; Pesaran, Ahmad

    2016-06-16

    This presentation discusses the impact of system design factors on battery aging and end of life. Topics include sizing of the SOC operating window, cell balancing and thermal management systems and their value in reducing pack degradation rates and cell imbalance growth over lifetime.

  16. GA -based energy management optimization for grid-connected photovoltaic system without battery storage

    International Nuclear Information System (INIS)

    This paper presents genetic algorithm (GA) based optimization of energy management for grid connected photovoltaic (PV) systems without battery storage. The major objective of this work is to minimize energy cost by maximizing objective function of GA considering both energy consumption and generation. In objective function calculation, PV module output power obtained by model of PV modules and previous power recordings from the PV system were employed. In the system, some electrical appliances and lights are in the energy consumption side and photovoltaic energy source connected to the grid is in the energy generation side. A simulation study was implemented to obtain energy cost savings using GA optimization in a commercial building. Due to the cost of the batteries, PV system is implemented without battery storage. Therefore, by adapting fluctuating PV energy generation with the time -flexible loads , an effort was aimed to develop a smart -grid strategy. Key words: energy management , PV system, genetic algorithms, optimization, load scheduling

  17. Capacity Optimization of Renewable Energy Sources and Battery Storage in an Autonomous Telecommunication Facility

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Pandžić, Hrvoje; Škrlec, Davor;

    2014-01-01

    . The annual capacity reduction that results from these cycles is calculated for two types of battery technologies, i.e., valve-regulated lead–acid (VRLA) and lithium–ion (Li–ion), and treated as an additional cost. Finally, all associated costs are added up and the ideal configuration is proposed....... by a central energy storage system (ESS), consisting of a battery and a fuel cell. The optimization is carried out as a robust mixed-integer linear program (RMILP), and results in different optimal solutions, depending on budgets of uncertainty, each of which yields different RES and storage capacities....... These solutions are then tested against a set of possible outcomes, thus simulating the future operation of the system. Since battery cycling is inevitable in this application, an algorithm that counts the number of cycles and associated depths of discharges (DoD) is applied to the optimization results...

  18. A Score Function for Optimizing the Cycle-Life of Battery-Powered Embedded Systems

    DEFF Research Database (Denmark)

    Wognsen, Erik Ramsgaard; Haverkort, Boudewijn; Jongerden, Marijn;

    2015-01-01

    An ever increasing share of embedded systems is powered by rechargeable batteries. These batteries deteriorate with the number of charge/discharge cycles they are subjected to, the so-called cycle life. In this paper, we propose the wear score function to compare and evaluate the relative impact...... of usage (charge and discharge) profiles on cycle life. The wear score function can not only be used to rank different usage profiles, these rankings can also be used as a criterion for optimizing the overall lifetime of a battery-powered system. We perform such an optimization on a nano-satellite case...... study provided by the company GomSpace. The scheduling of the system is modelled as a network of (stochastic) weighted timed games. In a stochastic setting, exact optimization is very expensive. However, the recently introduced Uppaal Stratego tool combines symbolic synthesis with statistical model...

  19. Using thermal balance model to determine optimal reactor volume and insulation material needed in a laboratory-scale composting reactor.

    Science.gov (United States)

    Wang, Yongjiang; Pang, Li; Liu, Xinyu; Wang, Yuansheng; Zhou, Kexun; Luo, Fei

    2016-04-01

    A comprehensive model of thermal balance and degradation kinetics was developed to determine the optimal reactor volume and insulation material. Biological heat production and five channels of heat loss were considered in the thermal balance model for a representative reactor. Degradation kinetics was developed to make the model applicable to different types of substrates. Simulation of the model showed that the internal energy accumulation of compost was the significant heat loss channel, following by heat loss through reactor wall, and latent heat of water evaporation. Lower proportion of heat loss occurred through the reactor wall when the reactor volume was larger. Insulating materials with low densities and low conductive coefficients were more desirable for building small reactor systems. Model developed could be used to determine the optimal reactor volume and insulation material needed before the fabrication of a lab-scale composting system.

  20. Optimizations of Battery-Based Intrusion Protection Systems

    OpenAIRE

    Nelson, Theresa Michelle

    2008-01-01

    As time progresses, small mobile devices become more prevalent for both personal and industrial use, providing malicious network users with new and exciting venues for security exploits. Standard security applications, such as Norton Antivirus and MacAfee, require computing power, memory space, and operating system complexity that are not present in small mobile devices. Recently, the Battery-Sensing Intrusion Protection System (B-SIPS) was devised as a means to correct the inability of small...

  1. Plug-in hybrid electric vehicle charge pattern optimization for energy cost and battery longevity

    Science.gov (United States)

    Bashash, Saeid; Moura, Scott J.; Forman, Joel C.; Fathy, Hosam K.

    This paper examines the problem of optimizing the charge pattern of a plug-in hybrid electric vehicle (PHEV), defined as the timing and rate with which the PHEV obtains electricity from the power grid. The optimization goal is to simultaneously minimize (i) the total cost of fuel and electricity and (ii) the total battery health degradation over a 24-h naturalistic drive cycle. The first objective is calculated for a previously-developed stochastic optimal PHEV power management strategy, whereas the second objective is evaluated through an electrochemistry-based model of anode-side resistive film formation in lithium-ion batteries. The paper shows that these two objectives are conflicting, and trades them off using a non-dominated sorting genetic algorithm. As a result, a Pareto front of optimal charge patterns is obtained. The effects of electricity price and trip schedule on the optimal Pareto points and the PHEV charge patterns are analyzed and discussed.

  2. Loading pattern optimization of PWR reactors using Artificial Bee Colony

    International Nuclear Information System (INIS)

    Highlights: → ABC algorithm is comparable to the canonical GA algorithm and PSO. → The performance of ABC shows that the algorithm is quiet promising. → The final band width of search fitness values by ABC is narrow. → The ABC algorithm is relatively easy to implement. - Abstract: In this paper a core reloading technique using Artificial Bee Colony algorithm, ABC, is presented in the context of finding an optimal configuration of fuel assemblies. The proposed method can be used for in-core fuel management optimization problems in pressurized water reactors. To evaluate the proposed technique, the power flattening of a VVER-1000 core is considered as an objective function although other variables such as Keff, power peaking factor, burn up and cycle length can also be taken into account. The proposed optimization method is applied to a core design optimization problem previously solved with Genetic and Particle Swarm Intelligence Algorithm. The results, convergence rate and reliability of the new method are quite promising and show that the ABC algorithm performs very well and is comparable to the canonical Genetic Algorithm and Particle Swarm Intelligence, hence demonstrating its potential for other optimization applications in nuclear engineering field as, for instance, the cascade problems.

  3. Optimization and Domestic Sourcing of Lithium Ion Battery Anode Materials

    Energy Technology Data Exchange (ETDEWEB)

    Wood, III, D. L.; Yoon, S. [A123 Systems, Inc.

    2012-10-25

    The purpose of this Cooperative Research and Development Agreement (CRADA) between ORNL and A123Systems, Inc. was to develop a low-temperature heat treatment process for natural graphite based anode materials for high-capacity and long-cycle-life lithium ion batteries. Three major problems currently plague state-of-the-art lithium ion battery anode materials. The first is the cost of the artificial graphite, which is heat-treated well in excess of 2000°C. Because of this high-temperature heat treatment, the anode active material significantly contributes to the cost of a lithium ion battery. The second problem is the limited specific capacity of state-of-the-art anodes based on artificial graphites, which is only about 200-350 mAh/g. This value needs to be increased to achieve high energy density when used with the low cell-voltage nanoparticle LiFePO4 cathode. Thirdly, the rate capability under cycling conditions of natural graphite based materials must be improved to match that of the nanoparticle LiFePO4. Natural graphite materials contain inherent crystallinity and lithium intercalation activity. They hold particular appeal, as they offer huge potential for industrial energy savings with the energy costs essentially subsidized by geological processes. Natural graphites have been heat-treated to a substantially lower temperature (as low as 1000-1500°C) and used as anode active materials to address the problems described above. Finally, corresponding graphitization and post-treatment processes were developed that are amenable to scaling to automotive quantities.

  4. Evaluation of Advanced Control for Li-ion Battery Balancing Systems using Convex Optimization

    DEFF Research Database (Denmark)

    Pinto, Claudio; Barreras, Jorge Varela; Schaltz, Erik;

    2016-01-01

    systems are evaluated in this paper by means of convex optimization. More than one hundred cases in a pure EV application are evaluated. Balancing circuits' efficiency models are implemented and realistic cell-to-cell parameter distributions are considered based on experimental data. Different battery...... of energy losses, available capacity or temperature are obtained for the last three categories, even for moderate balancing currents. In particular, remarkable improvements are observed under conditions of high power demand with high variability, i.e., smaller battery sizes and more demanding driving cycles....

  5. Modeling and Optimal Operation of Distributed Battery Storage in Low Voltage Grids

    OpenAIRE

    Fortenbacher, Philipp; Mathieu, Johanna L.; Andersson, Göran

    2016-01-01

    Due to high power in-feed from photovoltaics, it can be expected that more battery systems will be installed in the distribution grid in near future to mitigate voltage violations and thermal line and transformer overloading. In this paper, we present a two-stage centralized model predictive control scheme for distributed battery storage that consists of a scheduling entity and a real-time control entity. To guarantee secure grid operation, we solve a robust multi-period optimal power flow (O...

  6. Optimizing battery sizes of plug-in hybrid and extended range electric vehicles for different user types

    International Nuclear Information System (INIS)

    There are ambitious greenhouse gas emission (GHG) targets for the manufacturers of light duty vehicles. To reduce the GHG emissions, plug-in hybrid electric vehicle (PHEV) and extended range electric vehicle (EREV) are promising powertrain technologies. However, the battery is still a very critical component due to the high production cost and heavy weight. This paper introduces a holistic approach for the optimization of the battery size of PHEVs and EREVs under German market conditions. The assessment focuses on the heterogeneity across drivers, by analyzing the impact of different driving profiles on the optimal battery setup from total cost of ownership (TCO) perspective. The results show that the battery size has a significant effect on the TCO. For an average German driver (15,000 km/a), battery capacities of 4 kWh (PHEV) and 6 kWh (EREV) would be cost optimal by 2020. However, these values vary strongly with the driving profile of the user. Moreover, the optimal battery size is also affected by external factors, e.g. electricity and fuel prices or battery production cost. Therefore, car manufacturers should develop a modular design for their batteries, which allows adapting the storage capacity to meet the individual customer requirements instead of “one size fits all”. - Highlights: • Optimization of the battery size of PHEVs and EREVs under German market conditions. • Focus on heterogeneity across drivers (e.g. mileage, trip distribution, speed). • Optimal battery size strongly depends on the driving profile and energy prices. • OEMs require a modular design for their batteries to meet individual requirements

  7. Optimization of research reactor availability and reliability: Recommended practices

    International Nuclear Information System (INIS)

    For a select (and growing) population of research reactor organizations, an unplanned, forced, or otherwise inadvertent reactor shutdown or power reduction is a significant event - so significant that these organizations are willing to proactively invest resources to reduce these occurrences to a minimum. This report focuses on operation and maintenance programmes and best practices that have led to demonstrated performance improvements. The effort to develop the material relied on inputs from representatives of operating organizations with heavily utilized research reactors involved in activities that are highly sensitive to inadvertent automatic shutdowns, reductions in power, forced outages or unplanned outage extensions. The content of this report reflects efforts to achieve operational excellence. The relevance and importance of related safety and security programmes were repeatedly emphasized throughout the development of this report. The unanimous agreement from all involved is that fully developed and well implemented safety and security programmes, with all the relevant attributes including a well established safety culture and integral management system, among others, are an absolute prerequisite to optimize availability and reliability. Details about such programmes may be found in specifically referenced documents, as well as general references included in a bibliography. Other than these references, it is not the objective of this report to provide any recommendations, guidelines or practices aimed solely at improving facility safety. This report was developed over the course of two meetings in September 2006 and April 2007. Participants included operation and maintenance managers representing heavily utilized facilities with demonstrated operation and maintenance performance excellence. In these meetings a general outline was developed and then expanded to cover a range of programmes and activities that the participants identified as significant to

  8. Optimizing Battery Life for Electric UAVs using a Bayesian Framework

    Data.gov (United States)

    National Aeronautics and Space Administration — In summary, this paper lays a simple flight plan optimization strategy based on the particle filtering framework described in [5]. This is meant as a first step in...

  9. Study on the Optimal Charging Strategy for Lithium-Ion Batteries Used in Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Shuo Zhang

    2014-10-01

    Full Text Available The charging method of lithium-ion batteries used in electric vehicles (EVs significantly affects its commercial application. This paper aims to make three contributions to the existing literature. (1 In order to achieve an efficient charging strategy for lithium-ion batteries with shorter charging time and lower charring loss, the trade-off problem between charging loss and charging time has been analyzed in details through the dynamic programing (DP optimization algorithm; (2 To reduce the computation time consumed during the optimization process, we have proposed a database based optimization approach. After off-line calculation, the simulation results can be applied to on-line charge; (3 The novel database-based DP method is proposed and the simulation results illustrate that this method can effectively find the suboptimal charging strategies under a certain balance between the charging loss and charging time.

  10. Optimization of a combined electrocoagulation-electroflotation reactor.

    Science.gov (United States)

    Jiménez, C; Sáez, C; Cañizares, P; Rodrigo, M A

    2016-05-01

    This work studies the efficiency of an electroflotation process for the separation of the solids produced during the electrocoagulation treatment of three different types of wastewater: kaolin suspension, coloured organic solution and oil-in-water emulsion. Additionally, a combined electrocoagulation-electroflotation reactor is designed and optimized taking into account the effect of current density, residence time, pollutant concentration and the ratio floated/settled solids. To do this, an experimental design with response surface methodology (RSM) has been used. Results show that electroflotation is a good alternative to the removal of oil microdrops and dyes, but it is not recommended for the separation of solids formed during electrocoagulation of colloid suspensions due to its high density. It has been found that the use of aluminium leads to better results than the use of iron in the treatment of oil-in-water emulsions and coloured solutions. In these cases, the use of a combined electrocoagulation-electroflotation reactor is recommended and the effect of the main inputs has been studied.

  11. Optimization of a combined electrocoagulation-electroflotation reactor.

    Science.gov (United States)

    Jiménez, C; Sáez, C; Cañizares, P; Rodrigo, M A

    2016-05-01

    This work studies the efficiency of an electroflotation process for the separation of the solids produced during the electrocoagulation treatment of three different types of wastewater: kaolin suspension, coloured organic solution and oil-in-water emulsion. Additionally, a combined electrocoagulation-electroflotation reactor is designed and optimized taking into account the effect of current density, residence time, pollutant concentration and the ratio floated/settled solids. To do this, an experimental design with response surface methodology (RSM) has been used. Results show that electroflotation is a good alternative to the removal of oil microdrops and dyes, but it is not recommended for the separation of solids formed during electrocoagulation of colloid suspensions due to its high density. It has been found that the use of aluminium leads to better results than the use of iron in the treatment of oil-in-water emulsions and coloured solutions. In these cases, the use of a combined electrocoagulation-electroflotation reactor is recommended and the effect of the main inputs has been studied. PMID:26846247

  12. Optimal Power Scheduling for a Grid-Connected Hybrid PV-Wind-Battery Microgrid System

    DEFF Research Database (Denmark)

    Hernández, Adriana Carolina Luna; Aldana, Nelson Leonardo Diaz; Savaghebi, Mehdi;

    2016-01-01

    In this paper, a lineal mathematical model is proposed to schedule optimally the power references of the distributed energy resources in a grid-connected hybrid PVwind-battery microgrid. The optimization of the short term scheduling problem is addressed through a mixed-integer linear programming...... mathematical model, wherein the cost of energy purchased from the main grid is minimized and profits for selling energy generated by photovoltaic arrays are maximized by considering both physical constraints and requirements for a feasible deployment in the real system. The optimization model is tested...

  13. Optimization of Layered Cathode Materials for Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Christian Julien

    2016-07-01

    Full Text Available This review presents a survey of the literature on recent progress in lithium-ion batteries, with the active sub-micron-sized particles of the positive electrode chosen in the family of lamellar compounds LiMO2, where M stands for a mixture of Ni, Mn, Co elements, and in the family of yLi2MnO3•(1 − yLiNi½Mn½O2 layered-layered integrated materials. The structural, physical, and chemical properties of these cathode elements are reported and discussed as a function of all the synthesis parameters, which include the choice of the precursors and of the chelating agent, and as a function of the relative concentrations of the M cations and composition y. Their electrochemical properties are also reported and discussed to determine the optimum compositions in order to obtain the best electrochemical performance while maintaining the structural integrity of the electrode lattice during cycling.

  14. Optimal economy-based battery degradation management dynamics for fuel-cell plug-in hybrid electric vehicles

    Science.gov (United States)

    Martel, François; Kelouwani, Sousso; Dubé, Yves; Agbossou, Kodjo

    2015-01-01

    This work analyses the economical dynamics of an optimized battery degradation management strategy intended for plug-in hybrid electric vehicles (PHEVs) with consideration given to low-cost technologies, such as lead-acid batteries. The optimal management algorithm described herein is based on discrete dynamic programming theory (DDP) and was designed for the purpose of PHEV battery degradation management; its operation relies on simulation models using data obtained experimentally on a physical PHEV platform. These tools are first used to define an optimal management strategy according to the economical weights of PHEV battery degradation and the secondary energy carriers spent to manage its deleterious effects. We then conduct a sensitivity study of the proposed optimization process to the fluctuating economic parameters associated with the fuel and energy costs involved in the degradation management process. Results demonstrate the influence of each parameter on the process's response, including daily total operating costs and expected battery lifetime, as well as establish boundaries for useful application of the method; in addition, they provide a case for the relevance of inexpensive battery technologies, such as lead-acid batteries, for economy-centric PHEV applications where battery degradation is a major concern.

  15. SWAN-PPL, Fusion Reactor 1-D Particle Transport Optimization

    International Nuclear Information System (INIS)

    1 - Description of problem or function: Given the material density profiles which describe a one-dimensional reference system with a neutron source, SWAN will calculate, and optionally implement, density changes so as to optimize a single functional parameter of the system. 2 - Method of solution: The one-dimensional discrete-ordinate transport code ANISN is used to calculate flux and adjoint distributions for specified sources. The code SWIF calculates first-order estimates of the effect of material density changes on a goal functional, and from these evaluates effectiveness functions for the substitution of one material for another. Density distribution changes are then calculated which would optimize the goal functional, optionally subject to a constraint of holding another functional constant (to first order). 3 - Restrictions on the complexity of the problem: SWAN is not designed to analyze critical systems; it assumes that there is a fixed source, as in shielding or fusion reactor applications. Otherwise it is compatible with ANISN. All arrays are variably-dimensioned, so that there are no restrictions on individual dimensions

  16. Heterogeneous Nuclear Reactor Models for Optimal Xenon Control.

    Science.gov (United States)

    Gondal, Ishtiaq Ahmad

    Nuclear reactors are generally modeled as homogeneous mixtures of fuel, control, and other materials while in reality they are heterogeneous-homogeneous configurations comprised of fuel and control rods along with other materials. Similarly, for space-time studies of a nuclear reactor, homogeneous, usually one-group diffusion theory, models are used, and the system equations are solved by either nodal or modal expansion approximations. Study of xenon-induced problems has also been carried out using similar models and with the help of dynamic programming or classical calculus of variations or the minimum principle. In this study a thermal nuclear reactor is modeled as a two-dimensional lattice of fuel and control rods placed in an infinite-moderator in plane geometry. The two-group diffusion theory approximation is used for neutron transport. Space -time neutron balance equations are written for two groups and reduced to one space-time algebraic equation by using the two-dimensional Fourier transform. This equation is written at all fuel and control rod locations. Iodine -xenon and promethium-samarium dynamic equations are also written at fuel rod locations only. These equations are then linearized about an equilibrium point which is determined from the steady-state form of the original nonlinear system equations. After studying poisonless criticality, with and without control, and the stability of the open-loop system and after checking its controllability, a performance criterion is defined for the xenon-induced spatial flux oscillation problem in the form of a functional to be minimized. Linear -quadratic optimal control theory is then applied to solve the problem. To perform a variety of different additional useful studies, this formulation has potential for various extensions and variations; for example, different geometry of the problem, with possible extension to three dimensions, heterogeneous -homogeneous formulation to include, for example, homogeneously

  17. Vehicle trajectory optimization for hybrid vehicles taking into account battery state-of-charge

    OpenAIRE

    MENSING, Felicitas; TRIGUI, Rochdi; Bideaux, Eric

    2012-01-01

    Hybrid vehicles are found to be one solution to reduce fuel consumption in the transportation sector. Eco-driving is a concept that is immediately applicable by drivers to improve the efficiency of their vehicle. In this work the potential of eco-driving for hybrid drive train vehicles is discussed. The operation of hybrid vehicles is strongly dependent on their energy management and therefore on battery state-of-charge. Here, the velocity trajectory will be optimized taking into account b...

  18. Optimal Dispatch of Unreliable Electric Grid-Connected Diesel Generator-Battery Power Systems

    Science.gov (United States)

    Xu, D.; Kang, L.

    2015-06-01

    Diesel generator (DG)-battery power systems are often adopted by telecom operators, especially in semi-urban and rural areas of developing countries. Unreliable electric grids (UEG), which have frequent and lengthy outages, are peculiar to these regions. DG-UEG-battery power system is an important kind of hybrid power system. System dispatch is one of the key factors to hybrid power system integration. In this paper, the system dispatch of a DG-UEG-lead acid battery power system is studied with the UEG of relatively ample electricity in Central African Republic (CAR) and UEG of poor electricity in Congo Republic (CR). The mathematical models of the power system and the UEG are studied for completing the system operation simulation program. The net present cost (NPC) of the power system is the main evaluation index. The state of charge (SOC) set points and battery bank charging current are the optimization variables. For the UEG in CAR, the optimal dispatch solution is SOC start and stop points 0.4 and 0.5 that belong to the Micro-Cycling strategy and charging current 0.1 C. For the UEG in CR, the optimal dispatch solution is of 0.1 and 0.8 that belongs to the Cycle-Charging strategy and 0.1 C. Charging current 0.1 C is suitable for both grid scenarios compared to 0.2 C. It makes the dispatch strategy design easier in commercial practices that there are a few very good candidate dispatch solutions with system NPC values close to that of the optimal solution for both UEG scenarios in CAR and CR.

  19. Computational multiobjective topology optimization of silicon anode structures for lithium-ion batteries

    Science.gov (United States)

    Mitchell, Sarah L.; Ortiz, Michael

    2016-09-01

    This study utilizes computational topology optimization methods for the systematic design of optimal multifunctional silicon anode structures for lithium-ion batteries. In order to develop next generation high performance lithium-ion batteries, key design challenges relating to the silicon anode structure must be addressed, namely the lithiation-induced mechanical degradation and the low intrinsic electrical conductivity of silicon. As such this work considers two design objectives, the first being minimum compliance under design dependent volume expansion, and the second maximum electrical conduction through the structure, both of which are subject to a constraint on material volume. Density-based topology optimization methods are employed in conjunction with regularization techniques, a continuation scheme, and mathematical programming methods. The objectives are first considered individually, during which the influence of the minimum structural feature size and prescribed volume fraction are investigated. The methodology is subsequently extended to a bi-objective formulation to simultaneously address both the structural and conduction design criteria. The weighted sum method is used to derive the Pareto fronts, which demonstrate a clear trade-off between the competing design objectives. A rigid frame structure was found to be an excellent compromise between the structural and conduction design criteria, providing both the required structural rigidity and direct conduction pathways. The developments and results presented in this work provide a foundation for the informed design and development of silicon anode structures for high performance lithium-ion batteries.

  20. A Novel Design and Optimization Software for Autonomous PV/Wind/Battery Hybrid Power Systems

    Directory of Open Access Journals (Sweden)

    Ali M. Eltamaly

    2014-01-01

    Full Text Available This paper introduces a design and optimization computer simulation program for autonomous hybrid PV/wind/battery energy system. The main function of the new proposed computer program is to determine the optimum size of each component of the hybrid energy system for the lowest price of kWh generated and the best loss of load probability at highest reliability. This computer program uses the hourly wind speed, hourly radiation, and hourly load power with several numbers of wind turbine (WT and PV module types. The proposed computer program changes the penetration ratio of wind/PV with certain increments and calculates the required size of all components and the optimum battery size to get the predefined lowest acceptable probability. This computer program has been designed in flexible fashion that is not available in market available software like HOMER and RETScreen. Actual data for Saudi sites have been used with this computer program. The data obtained have been compared with these market available software. The comparison shows the superiority of this computer program in the optimal design of the autonomous PV/wind/battery hybrid system. The proposed computer program performed the optimal design steps in very short time and with accurate results. Many valuable results can be extracted from this computer program that can help researchers and decision makers.

  1. Geometric Process-Based Maintenance and Optimization Strategy for the Energy Storage Batteries

    Directory of Open Access Journals (Sweden)

    Yan Li

    2016-01-01

    Full Text Available Renewable energy is critical for improving energy structure and reducing environment pollution. But its strong fluctuation and randomness have a serious effect on the stability of the microgrid without the coordination of the energy storage batteries. The main factors that influence the development of the energy storage system are the lack of valid operation and maintenance management as well as the cost control. By analyzing the typical characteristics of the energy storage batteries in their life cycle, the geometric process-based model including the deteriorating system and the improving system is firstly built for describing the operation process, the preventive maintenance process, and the corrective maintenance process. In addition, this paper proposes an optimized management strategy, which aims to minimize the long-run average cost of the energy storage batteries by defining the time interval of the detection and preventive maintenance process as well as the optimal corrective maintenance times, subjected to the state of health and the reliability conditions. The simulation is taken under the built model by applying the proposed energy storage batteries’ optimized management strategy, which verifies the effectiveness and applicability of the management strategy, denoting its obvious practicality on the current application.

  2. Optimized synthesis technology of LiFePO4 for Li-ion battery

    Institute of Scientific and Technical Information of China (English)

    QU Tao; TIAN Yan-wen; DING Yang; ZHONG Can-yun; ZHAI Yu-chun

    2005-01-01

    The influence of factors of the carbon black content, sintering temperature, sintering time, molar ratio of Li to Fe, as well as the electrochemical properties of LiFePO4 for lithium ion battery were studied. The only technology was obtained by using range analysis through Latin orthogonal experiment of L44 (16). The results show that the optimization synthesis technology of LiFePO4 is content of 5% doping carbon, sintering temperature of 700 ℃,molar ratio of Li to Fe of 1.03 : 1 and sintering time of 16 h. The optimized cathode synthesis techniques can make LiFePO4 have good electrochemical properties.

  3. CFD optimization of continuous stirred-tank (CSTR) reactor for biohydrogen production.

    Science.gov (United States)

    Ding, Jie; Wang, Xu; Zhou, Xue-Fei; Ren, Nan-Qi; Guo, Wan-Qian

    2010-09-01

    There has been little work on the optimal configuration of biohydrogen production reactors. This paper describes three-dimensional computational fluid dynamics (CFD) simulations of gas-liquid flow in a laboratory-scale continuous stirred-tank reactor used for biohydrogen production. To evaluate the role of hydrodynamics in reactor design and optimize the reactor configuration, an optimized impeller design has been constructed and validated with CFD simulations of the normal and optimized impeller over a range of speeds and the numerical results were also validated by examination of residence time distribution. By integrating the CFD simulation with an ethanol-type fermentation process experiment, it was shown that impellers with different type and speed generated different flow patterns, and hence offered different efficiencies for biohydrogen production. The hydrodynamic behavior of the optimized impeller at speeds between 50 and 70 rev/min is most suited for economical biohydrogen production.

  4. Numerical analyses on optimizing a heat pipe thermal management system for lithium-ion batteries during fast charging

    International Nuclear Information System (INIS)

    Thermal management is crucial for the operation of electric vehicles because lithium ion batteries are vulnerable to excessive heat generation during fast charging or other severe scenarios. In this work, an optimized heat pipe thermal management system (HPTMS) is proposed for fast charging lithium ion battery cell/pack. A numerical model is developed and comprehensively validated with experimental results. This model is then employed to investigate the thermal performance of the HPTMS under steady state and transient conditions. It is found that a cylinder vortex generator placed in front of the heat pipe condensers in the coolant stream improves the temperature uniformity. The uses of cooper heat spreaders and cooling fins greatly improve the performance of the thermal management system. Experiments and transient simulations of heat pipe thermal management system integrated with batteries prove that the improved HPTMS is capable for thermal management of batteries during fast charging. The air-cooled HPTMS is infeasible for thermal management of batteries during fast charging at the pack level due to the limitation of low specific heat capacity. - Highlights: • We develop a numerical model for optimizing a heat pipe thermal management system for fast charging batteries. • The numerical model is comprehensively validated with experimental data. • A cylinder vortex generator is placed at the inlet of the cooling stream to improve the temperature uniformity. • We validate the effectiveness of the optimized system with integration of prismatic batteries

  5. Shape optimization of a Sodium Fast Reactor core

    Directory of Open Access Journals (Sweden)

    Dombre Emmanuel

    2013-01-01

    Full Text Available We apply in this paper a geometrical shape optimization method for the design of the core of a SFR (Sodium-cooled Fast Reactor in order to minimize a thermal counter-reaction known as the sodium void effect. In this kind of reactors, by increasing the temperature, the core may become liable to a strong increase of reactivity, a key-parameter governing the chain-reaction at quasi-static states. We first use the one group energy diffusion model and give the generalization to the two groups energy equation. We then give some numerical results in the case of the one group energy equation. Note that the application of our method leads to some designs whose interfaces can be parametrized by very smooth curves which can stand very far from realistic designs. We don’t explain here the method that it would be possible to use for recovering an operational design but there exists several penalization methods (see [2] that could be employed to this end. On applique dans cet article une méthode d’optimisation géométrique dans le cadre de la conception d’un cœur de réacteur SFR (Sodium-cooled Fast Reactor, i.e. réacteur à neutron rapide refroidi au sodium dans le but de minimiser une contre réaction thermique connue sous le nom d’effet de vidange sodium. Lorsqu’une augmentation de température survient, ce type de réacteur peut être sujet à une forte augmentation de réactivité, un paramètre clé dans le contrôle de la réaction en chaîne en régime quasi-statique. On a recours à l’équation de diffusion à un groupe puis on donne la généralisation du modèle d’optimisation pour l’équation de la diffusion à deux groupes d’énergie. On présente ensuite quelques résultats numériques obtenus dans le cas de l’équation à un groupe d’énergie. On note que l’application de cette méthode conduit à des designs de cœur présentant des interfaces très régulières qui sont loin d’un design de cœur faisable sur le

  6. Fuel reactor modelling in chemical-looping combustion of coal: 2. simulation and optimization

    OpenAIRE

    García Labiano, Francisco; Diego Poza, Luis F. de; Gayán Sanz, Pilar; Abad Secades, Alberto; Adánez Elorza, Juan

    2013-01-01

    Chemical-Looping Combustion of coal (CLCC) is a promising process to carry out coal combustion with carbon capture. The process should be optimized in order to maximize the carbon capture and the combustion efficiency in the fuel reactor, which will depend on the reactor design and the operational conditions. In this work, a mathematical model of the fuel reactor is used to make predictions about the performance of the CLCC process and simulate the behaviour of the system ...

  7. Biological sulfuric acid transformation: Reactor design and process optimization.

    Science.gov (United States)

    Stucki, G; Hanselmann, K W; Hürzeler, R A

    1993-02-01

    As an alternative to the current disposal technologies for waste sulfuric acid, a new combination of recycling processes was developed. The strong acid (H(2)SO(4)) is biologically converted with the weak acid (CH(3)COOH) into two volatile weak acids (H(2)S, H(2)CO(3)) by sulfate-reducing bacteria. The transformation is possible without prior neutralization of the sulfuric acid. The microbially mediated transformation can be followed by physiochemical processes for the further conversion of the H(2)S.The reduction of sulfate to H(2)S is carried out under carbon-limited conditions at pH 7.5 to 8.5. A fixed-bed biofilm column reactor is used in conjunction with a separate gas-stripping column which was installed in the recycle stream. Sulfate, total sulfide, and the carbon substrate (in most cases acetate) were determined quantitatively. H(2)S and CO(2) are continually removed by stripping with N(2). Optimal removal is achieved under pH conditions which are adjusted to values below the pK(a)-values of the acids. The H(2)S concentration in the stripped gas was 2% to 8% (v/v) if H(2)SO(4) and CH(3)COOH are fed to the recycle stream just before the stripping column.Microbiol conversion rates of 65 g of sulfate reduced per liter of bioreactor volume per day are achieved and bacterial conversion efficiencies for sulfate of more than 95% can be maintained if the concentration of undissociated H(2)S is kept below 40 to 50 mg/L. Porous glass spheres, lava beads, and polyurethane pellets are useful matrices for the attachment of the bacterial biomass. Theoretical aspects and the dependence of the overall conversion performance on selected process parameters are illustrated in the Appendix to this article. PMID:18609554

  8. Optimized conventional island design for the European Pressurized Water Reactor

    International Nuclear Information System (INIS)

    German and French designers agreed in 1989 to jointly develop a standardized nuclear island for the European Pressurized Water Reactor (EPR). With the support of German and French utilities and safety authorities, the basic design was started 1995 and was finalized by the end of 1998. In parallel with these efforts, the German utilities group contracted the Power Generation Group (KWU) of Siemens AG to develop an optimized conventional island for the EPR. The main objective of the EPR design, i.e. to be able to compete economically with other nuclear power plant designs and fossil-fuel power plants and at the same time to increase nuclear safety, has been achieved. The results of these optimization efforts on the conventional island side can be summarized in the following points: - The plant's electrical generating capacity was increased without any need of additional or new special tools or equipment. - The entire development and implementation process, i.e. from plant design work all the way through to plant service and maintenance, was reviewed and improved without any restricting operational or maintenance aspects. - The efficiency of the steam, condensate and feedwater cycle, including the steam turbine and heat sink, was increased by introducing, among other design changes, the new 3DS/3DV blade design. - Common general European codes and related national codes and standards were applied to the designing, sizing, approval and documentation of all conventional island components. - Only specialized personnel with global turn-key know-how were involved. The result is a nuclear power plant with a gross electrical generating capacity of 1850 MW (for a site equippped with cooling tower), a gross efficiency rate of 37.8 percent and a net efficiency of 35.9 percent. The performance figures of the improved design demonstrate the following: - The EPR is economically competitive with modern fossil-fuel power plants. - The EPR is much less dependent on fuel cycle costs

  9. Modified divergence theorem for analysis and optimization of wall reflecting cylindrical UV reactor

    Directory of Open Access Journals (Sweden)

    Milanović Đurđe R.

    2011-01-01

    Full Text Available In this paper, Modified Divergence Theorem (MDT, known in earlier literature as Gauss-Ostrogradsky theorem, was formulated and proposed as a general approach to electromagnetic (EM radiation, especially ultraviolet (UV radiation reactor modeling. Formulated mathematical model, based on MDT, for multilamp UV reactor was applied to all sources in a reactor in order to obtain intensity profiles at chosen surfaces inside reactor. Applied modification of MDT means that intensity at a real opaque or transparent surface or through a virtual surface, opened or closed, from different sides of the surface are added and not subtracted as in some other areas of physics. Derived model is applied to an example of the multiple UV sources reactor, where sources are arranged inside a cylindrical reactor at the coaxial virtual cylinder, having the radius smaller than the radius of the reactor. In this work, optimization of a reactor means maximum transfer of EM energy sources into the fluid for given fluid absorbance and fluid flow-dose product. Obtained results, for in advanced known water quality, gives unique solution for an optimized model of a multilamp reactor geometry. As everyone can easily verify, MDT is very good starting point for every reactor modeling and analysis.

  10. Modeling-based optimization of a fixed-bed industrial reactor for oxidative dehydrogenation of propane

    Institute of Scientific and Technical Information of China (English)

    Ali Darvishi; Razieh Davand; Farhad Khorasheh; Moslem Fattahi

    2016-01-01

    An industrial scale propylene production via oxidative dehydrogenation of propane (ODHP) in multi-tubular re-actors was modeled. Multi-tubular fixed-bed reactor used for ODHP process, employing 10000 of smal diameter tubes immersed in a shel through a proper coolant flows. Herein, a theory-based pseudo-homogeneous model to describe the operation of a fixed bed reactor for the ODHP to correspondence olefin over V2O5/γ-Al2O3 catalyst was presented. Steady state one dimensional model has been developed to identify the operation parameters and to describe the propane and oxygen conversions, gas process and coolant temperatures, as well as other pa-rameters affecting the reactor performance such as pressure. Furthermore, the applied model showed that a double-bed multitubular reactor with intermediate air injection scheme was superior to a single-bed design due to the increasing of propylene selectivity while operating under lower oxygen partial pressures resulting in propane conversion of about 37.3%. The optimized length of the reactor needed to reach 100%conversion of the oxygen was theoretically determined. For the single-bed reactor the optimized length of 11.96 m including 0.5 m of inert section at the entrance region and for the double-bed reactor design the optimized lengths of 5.72 m for the first and 7.32 m for the second reactor were calculated. Ultimately, the use of a distributed oxygen feed with limited number of injection points indicated a significant improvement on the reactor performance in terms of propane conversion and propylene selectivity. Besides, this concept could overcome the reactor run-away temperature problem and enabled operations at the wider range of conditions to obtain enhanced propyl-ene production in an industrial scale reactor.

  11. Optimal Operation Method for Microgrid with Wind/PV/Diesel Generator/Battery and Desalination

    Directory of Open Access Journals (Sweden)

    Qingfeng Tang

    2014-01-01

    Full Text Available The power supply mode of island microgrid with a variety of complementary energy resources is one of the most effective ways to solve the problem of future island power supply. Based on the characteristics of seawater desalination system and water demand of island residents, a power allocation strategy for seawater desalination load, storage batteries, and diesel generators is proposed with the overall consideration of the economic and environmental benefits of system operation. Furthermore, a multiobjective optimal operation model for the island microgrid with wind/photovoltaic/diesel/storage and seawater desalination load is also proposed. It first establishes the objective functions which include the life loss of storage batteries and the fuel cost of diesel generators. Finally, the model is solved by the nondominated sorting genetic algorithm (NSGA-II. The island microgrid in a certain district is taken as an example to verify the effectiveness of the proposed optimal method. The results provide the theoretical and technical basis for the optimal operation of island microgrid.

  12. Design and parametric optimization of thermal management of lithium-ion battery module with reciprocating air-flow

    Institute of Scientific and Technical Information of China (English)

    刘燕平; 欧阳陈志; 江清柏; 梁波

    2015-01-01

    Single cell temperature difference of lithium-ion battery (LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics (CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.

  13. Optimal operation strategy of battery energy storage system to real-time electricity price in Denmark

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    Since the hourly spot market price is available one day ahead, the price could be transferred to the consumers and they may have some motivations to install an energy storage system in order to save their energy costs. This paper presents an optimal operation strategy for a battery energy storage...... system (BESS) in relation to the real-time electricity price in order to achieve the maximum profits of the BESS. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may represent the future of electricity...

  14. Development of a graphical interface computer code for reactor fuel reloading optimization

    International Nuclear Information System (INIS)

    This report represents the results of the project performed in 2007. The aim of this project is to develop a graphical interface computer code that allows refueling engineers to design fuel reloading patterns for research reactor using simulated graphical model of reactor core. Besides, this code can perform refueling optimization calculations based on genetic algorithms as well as simulated annealing. The computer code was verified based on a sample problem, which relies on operational and experimental data of Dalat research reactor. This code can play a significant role in in-core fuel management practice at nuclear research reactor centers and in training. (author)

  15. Optimizing battery sizes of plug-in hybrid and extended range electric vehicles for different user types

    OpenAIRE

    REDELBACH Martin; Özdemir, Enver Doruk; Friedrich, Horst E.

    2014-01-01

    There are ambitious greenhouse gas emissions (GHG) targets for the manufacturers of light duty vehicles. To reduce the GHG emissions, plug-in hybrid electric vehicle (PHEV) and extended range electric vehicle (EREV) are promising powertrain technologies. However, the battery is still a very critical component due to the high production cost and heavy weight. This paper introduces a holistic approach for the optimization of the battery size of PHEVs and EREVs under German market conditions. Th...

  16. Optimization of the core of a 600 MV HTGR reactor

    International Nuclear Information System (INIS)

    Through a thermal analysis, several reactor core parameters are considered, viz.: cooling channel diameter, juel channel diameter, distance between two channels power generated for lenght unit, etc. Using several criteria, the best solution or solutions are chosen

  17. Modeling, simulation, and optimization of a front-end system for acetylene hydrogenation reactors

    Directory of Open Access Journals (Sweden)

    Gobbo R.

    2004-01-01

    Full Text Available The modeling, simulation, and dynamic optimization of an industrial reaction system for acetylene hydrogenation are discussed in the present work. The process consists of three adiabatic fixed-bed reactors, in series, with interstage cooling. These reactors are located after the compression and the caustic scrubbing sections of an ethylene plant, characterizing a front-end system; in contrast to the tail-end system where the reactors are placed after the de-ethanizer unit. The acetylene conversion and selectivity profiles for the reactors are optimized, taking into account catalyst deactivation and process constraints. A dynamic optimal temperature profile that maximizes ethylene production and meets product specifications is obtained by controlling the feed and intercoolers temperatures. An industrial acetylene hydrogenation system is used to provide the necessary data to adjust kinetics and transport parameters and to validate the approach.

  18. Optimal recharging strategy for battery-switch stations for electric vehicles in France

    International Nuclear Information System (INIS)

    Most papers that study the recharging of electric vehicles focus on charging the batteries at home and at the work-place. The alternative is for owners to exchange the battery at a specially equipped battery switch station (BSS). This paper studies strategies for the BSS to buy and sell the electricity through the day-ahead market. We determine what the optimal strategies would have been for a large fleet of EVs in 2010 and 2011, for the V2G and the G2V cases. These give the amount that the BSS should offer to buy or sell each hour of the day. Given the size of the fleet, the quantities of electricity bought and sold will displace the market equilibrium. Using the aggregate offers to buy and the bids to sell on the day-ahead market, we compute what the new prices and volumes transacted would be. While buying electricity for the G2V case incurs a cost, it would have been possible to generate revenue in the V2G case, if the arrivals of the EVs had been evenly spaced during the day. Finally, we compare the total cost of implementing the strategies with the cost of buying the same quantity of electricity from EDF. - Highlights: • Optimal strategies for buying/selling electricity through day-ahead auction market. • Given fleet size power bought and sold would change market price and volume. • New prices computed using aggregate offers to buy/sell power in 2010 and 2011. • Timing of arrival of EVs critical in V2G case. If evenly spaced BSS makes money. • Strategies are very robust even when French and German markets were coupled Nov. 2010

  19. Optimal charging method for lithium ion batteries using a universal voltage protocol accommodating aging

    Science.gov (United States)

    Guo, Zhen; Liaw, Bor Yann; Qiu, Xinping; Gao, Lanlan; Zhang, Changshui

    2015-01-01

    An effective optimum charging technique for lithium ion batteries using a universal voltage protocol (UVP) that can accommodate cell aging is presented here. This charging method demands less learning to varying state-of-health (SOH) conditions with potential to improve charging efficiency and cycle life. The simplicity of UVP makes the implementation easier than the conventional constant current-constant voltage (CC-CV)-based methods. Here, the mathematical formulation, optimization targets (e.g. minimal time) and constraints (terminal voltages and other instrumental and cell electrochemistry-limited ones) are explained from the protocol design considerations. An equivalent circuit model was used and its parameters derived from the analysis of test data, which could yield a nonlinear varying current profile (VCP) by simulation and a genetic algorithm-based optimization. Both UVP and VCP were used in the validation to illustrate better charging efficiency and capacity retention, which showed a much improved cycle life.

  20. Optimal Planning Strategy for Large PV/Battery System Based on Long-Term Insolation Forecasting

    Science.gov (United States)

    Yona, Atsushi; Uchida, Kosuke; Senjyu, Tomonobu; Funabashi, Toshihisa

    Photovoltaic (PV) systems are rapidly gaining acceptance as some of the best alternative energy sources. Usually the power output of PV system fluctuates depending on weather conditions. In order to control the fluctuating power output for PV system, it requires control method of energy storage system. This paper proposes an optimization approach to determine the operational planning of power output for PV system with battery energy storage system (BESS). This approach aims to obtain more benefit for electrical power selling and to smooth the fluctuating power output for PV system. The optimization method applies genetic algorithm (GA) considering PV power output forecast error. The forecast error is based on our previous works with the insolation forecasting at one day ahead by using weather reported data, fuzzy theory and neural network(NN). The validity of the proposed method is confirmed by the computer simulations.

  1. Optimization of Performance Characteristics of Hybrid Wind Photovoltaic System with Battery Storage

    Directory of Open Access Journals (Sweden)

    C. Kathirvel

    2014-03-01

    Full Text Available This study concentrates on the Design and Implementation of a multi source hybrid Wind-Photovoltaic stand alone system with proposed energy management strategy. The method of investigation concerned with the definition of the system topology, interconnection of the various sources with maximum energy transfer, optimum control and energy management in order to maintain the DC bus voltage into a fixed value. An Energy management strategy was proposed using the Fuzzy logic controller such that enhancement in the performance of the system and optimization can be done. The Fuzzy logic controller takes the input from Solar (irradiation, Wind (speed, Power demand and the battery voltage which controls the respective subsystem and formulates into different operational modes of energy management. The role of Fuzzy threshold controller is to adjust continuously the threshold value for optimal performance based on expected wind, solar conditions, battery voltage and power demand. It is shown that when the fuzzy logic controller is used, the proposed DC bus voltage regulation strategy with different modes of operation have fast response and efficient operation which leads to a reduced operating cost.

  2. Optimal vehicle control strategy of a fuel cell/battery hybrid city bus

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Liangfei; Li, Jianqiu; Hua, Jianfeng; Li, Xiangjun; Ouyang, Minggao [State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084 (China)

    2009-09-15

    In this article, an optimal vehicle control strategy based on a time-triggered controller area network (TTCAN) system for a polymer electrolyte membrane (PEM) fuel cell/nickel-metal hydride (Ni-MH) battery powered city bus is presented. Aiming at improving the fuel economy of the city bus, the control strategy comprises an equivalent consumption minimization strategy (ECMS) and a braking energy regeneration strategy (BERS). On the basis of the introduction of a battery equivalent hydrogen consumption model incorporating a charge-sustaining coefficient, an analytical solution to the equivalent consumption minimization problem is given. The proposed strategy has been applied in several city buses for the Beijing Olympic Games of 2008. Results of the ''China city bus typical cycle'' testing show that, the ECMS and the BERS lowered hydrogen consumption by 2.5% and 15.3% respectively, compared with a rule-based strategy. The BERS contributes much more than the ECMS to the fuel economy, because the fuel cell system does not leave much room for the optimal algorithm in improving the efficiency. (author)

  3. On the Optimization of the Fuel Distribution in a Nuclear Reactor

    DEFF Research Database (Denmark)

    Thevenot, Laurent

    2004-01-01

    In this paper we give an optimality condition for the optimization problem of the distribution of fuel assemblies in a nuclear reactor by using the homogenization method. This study deals with purely fissile fuels and is based on the neutron transport equation modeling for continuous models. In p...

  4. Optimized Control Rods of the BR2 Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kalcheva, Silva; Koonen, E.

    2007-09-15

    At the present time the BR-2 reactor uses control elements with cadmium as neutron absorbing part. The lower section of the control element is a beryllium assembly cooled by light water. Due to the burn up of the lower end of the cadmium section during the reactor operation, the presently used rods for reactivity control of the BR-2 reactor have to be replaced by new ones. Considered are various types Control Rods with full active part of the following materials: cadmium (Cd), hafnium (Hf), europium oxide (Eu2O3) and gadolinium (Gd2O3). Options to decrease the burn up of the control rod material in the hot spot, such as use of stainless steel in the lower active part of the Control Rod are discussed. Comparison with the characteristics of the presently used Control Rods types is performed. The changing of the characteristics of different types Control Rods and the perturbation effects on the reactor neutronics during the BR-2 fuel cycle are investigated. The burn up of the Control Rod absorbing material, total and differential control rods worth, macroscopic and effective microscopic absorption cross sections, fuel and reactivity evolution are evaluated during approximately 30 operating cycles.

  5. Optimal battery charging, Part I: Minimizing time-to-charge, energy loss, and temperature rise for OCV-resistance battery model

    Science.gov (United States)

    Abdollahi, A.; Han, X.; Avvari, G. V.; Raghunathan, N.; Balasingam, B.; Pattipati, K. R.; Bar-Shalom, Y.

    2016-01-01

    In this paper we present a closed-form solution to the problem of optimally charging a Li-ion battery. A combination of three cost functions is considered as the objective function: time-to-charge (TTC), energy losses (EL), and a temperature rise index (TRI). First, we consider the cost function of the optimization problem as a weighted sum of TTC and EL. We show that the optimal charging strategy in this case is the well-known Constant Current-Constant Voltage (CC-CV) policy with the value of the current in the CC stage being a function of the ratio of weighting on TTC and EL and of the resistance of the battery. Then, we extend the cost function to a weighted sum of TTC, EL and TRI and derive an analytical solution for the problem. It is shown that the analytical solution can be approximated by a CC-CV with the value of current in the CC stage being a function of ratio of weighting on TTC and EL, resistance of the battery and the effective thermal resistance.

  6. On an optimized neutron shielding for an advanced molten salt fast reactor design

    International Nuclear Information System (INIS)

    The molten salt reactor technology has gained renewed interest. In contrast to the historic molten salt reactors, the current projects are based on designing a molten salt fast reactor. Thus the shielding becomes significantly more challenging than in historic concepts. One very interesting and innovative result of the most recent EURATOM project on molten salt reactors – EVOL – is the fluid flow optimized design of the inner core vessel using curved blanket walls. The developed structure leads to a very uniform flow distribution. The design avoids all core internal structures. On the basis of this new geometry a model for neutron physics calculation is presented and applied for a shielding optimization. Based on these results an optimized shielding strategy is developed for the molten salt fast reactor to keep the fluence in the safety related outer vessel below expected limit values. A lifetime of 80 years can be assured, but the size of the core/blanket system has to be significantly increased and will finally be comparable to a sodium cooled fast reactor. The HELIOS results are verified against Monte-Carlo calculations with very satisfactory agreement for a deep penetration problem. (author)

  7. Geometric optimization of a solar cubic-cavity multi-tubular reactor

    Science.gov (United States)

    Valades-Pelayo, P. J.; Arancibia-Bulnes, C. A.; Villafan-Vidales, H.; Romero-Paredes, H.

    2016-05-01

    A multi-tubular solar thermochemical cavity reactor is proposed and the tubular array optimized. The optimized reactor design aims at operating under different temperatures and carrying out different kinds of thermochemical reactions. The radiation entering the receptacle comes from a solar concentrating system and the reactor consists of a cubic receptacle made of woven graphite, housing nine 2.54 cm diameter tungsten tubes. A model is developed and implemented considering high-temperature radiative transfer at steady state. The temperature distribution within the cavity surfaces is determined by employing a hybrid Monte Carlo-Finite Volume approach. Optimal tube distributions are explored by using a custom-made stochastic, multi-parameter, optimization algorithm. In this way, multiple global maxima are determined. Patterns among all possible optimal tube distributions within the cavity are obtained for different scenarios, by maximizing average tube temperature. From this study, practical guidelines are obtained for future application in the design of solar cavity reactors and more specifically, on the layout of multi tubular arrays to optimize radiative heat transfer.

  8. Improved electrochemical performance for vanadium flow battery by optimizing the concentration of the electrolyte

    Science.gov (United States)

    Jing, Minghua; Wei, Zengfu; Su, Wei; He, Hongxiang; Fan, Xinzhuang; Qin, Ye; Liu, Jianguo; Yan, Chuanwei

    2016-08-01

    In order to improve the utilization rate of the electrolyte and further reduce the energy storage cost, the physicochemical properties, electrochemical characteristics and charge/discharging behaviors of VFB with different concentration of VOSO4 and H2SO4 were investigated systematically. The physicochemical characterizations show that the viscosity increases with the increasing concentration of VOSO4 and H2SO4, and the conductivity increases with the increasing concentration of H2SO4 while decreases with the increasing concentration of VOSO4. Both CV and EIS results demonstrate that the electrolyte with 1.6 mol L-1 VOSO4 and 2.8 mol L-1 H2SO4 presents the best electrochemical performance because of the coupling effect of the viscosity, conductivity and electrochemical activity. Different with the half-cell electrochemical tests, the battery performance of VFB is not only dependent on the electrochemical activity of electrode/electrolyte interface, but also closely related to the conductivity of electrolyte and diffusion rates of the active particles between anolyte and catholyte. Taking the battery efficiencies and capacity into consideration, VFB with 1.6 mol L-1 VOSO4 and 2.8 mol L-1 H2SO4 exhibits the optimal electrochemical performance. The accomplishment of this work not only gives data support to the fundamental research of VFB, but also provides theoretical direction to the engineering application of VFB.

  9. Inverse parameter determination in the development of an optimized lithium iron phosphate - Graphite battery discharge model

    Science.gov (United States)

    Maheshwari, Arpit; Dumitrescu, Mihaela Aneta; Destro, Matteo; Santarelli, Massimo

    2016-03-01

    Battery models are riddled with incongruous values of parameters considered for validation. In this work, thermally coupled electrochemical model of the pouch is developed and discharge tests on a LiFePO4 pouch cell at different discharge rates are used to optimize the LiFePO4 battery model by determining parameters for which there is no consensus in literature. A discussion on parameter determination, selection and comparison with literature values has been made. The electrochemical model is a P2D model, while the thermal model considers heat transfer in 3D. It is seen that even with no phase change considered for LiFePO4 electrode, the model is able to simulate the discharge curves over a wide range of discharge rates with a single set of parameters provided a dependency of the radius of the LiFePO4 electrode on discharge rate. The approach of using a current dependent radius is shown to be equivalent to using a current dependent diffusion coefficient. Both these modelling approaches are a representation of the particle size distribution in the electrode. Additionally, the model has been thermally validated, which increases the confidence level in the selection of values of parameters.

  10. Improved performance of parallel surface/packed-bed discharge reactor for indoor VOCs decomposition: optimization of the reactor structure

    Science.gov (United States)

    Jiang, Nan; Hui, Chun-Xue; Li, Jie; Lu, Na; Shang, Ke-Feng; Wu, Yan; Mizuno, Akira

    2015-10-01

    The purpose of this paper is to develop a high-efficiency air-cleaning system for volatile organic compounds (VOCs) existing in the workshop of a chemical factory. A novel parallel surface/packed-bed discharge (PSPBD) reactor, which utilized a combination of surface discharge (SD) plasma with packed-bed discharge (PBD) plasma, was designed and employed for VOCs removal in a closed vessel. In order to optimize the structure of the PSPBD reactor, the discharge characteristic, benzene removal efficiency, and energy yield were compared for different discharge lengths, quartz tube diameters, shapes of external high-voltage electrode, packed-bed discharge gaps, and packing pellet sizes, respectively. In the circulation test, 52.8% of benzene was removed and the energy yield achieved 0.79 mg kJ-1 after a 210 min discharge treatment in the PSPBD reactor, which was 10.3% and 0.18 mg kJ-1 higher, respectively, than in the SD reactor, 21.8% and 0.34 mg kJ-1 higher, respectively, than in the PBD reactor at 53 J l-1. The improved performance in benzene removal and energy yield can be attributed to the plasma chemistry effect of the sequential processing in the PSPBD reactor. The VOCs mineralization and organic intermediates generated during discharge treatment were followed by CO x selectivity and FT-IR analyses. The experimental results indicate that the PSPBD plasma process is an effective and energy-efficient approach for VOCs removal in an indoor environment.

  11. Simplified Design and Optimization of Slotless Synchronous PM Machine for Micro-Satellite Electro-Mechanical Batteries

    Directory of Open Access Journals (Sweden)

    ABDI, B.

    2009-10-01

    Full Text Available Electro-mechanical batteries have important advantages as compared with chemical batteries, especially in low earth orbit satellites applications. High speed slotless external rotor permanent magnet machines are used in these systems as Motor/Generator. Proper material and structure for space applications are introduced. A simplified analytic design method is given for this type of machines. Finally, the optimization of machine in order to have maximum efficiency and minimum volume and weight are given in this paper. Particle swarm optimization is used as the optimization algorithm and the finite element-based simulations are used to confirm the design and optimization process and show less than 1.2% error in parametric design.

  12. Optimal design of hollow core–shell structural active materials for lithium ion batteries

    Directory of Open Access Journals (Sweden)

    Wenjuan Jiang

    2015-01-01

    Full Text Available To mitigate mechanical and chemical degradation of active materials, hollow core–shell structures have been applied in lithium ion batteries. Without embedding of lithium ions, the rigid coating shell can constrain the inward volume deformation. In this paper, optimal conditions for the full use of inner hollow space are identified in terms of the critical ratio of shell thickness and inner size and the state of charge. It is shown that the critical ratios are 0.10 and 0.15 for Si particle and tube (0.12 and 0.18 for Sn particle and tube, and above which there is lack of space for further lithiation.

  13. Optimizing pyrolysis of resin carbon for anode of lithium ion batteries

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Pyrolytic resin carbon anode for lithoum ion batteries was prepared from thermosetting phenolic resin.Pyrolysis of the primary phenolic resin and the dewatered one was studied by thermal gravimetric analysis. Structures and characteristics of the carbon materials were determined by X-ray diffraction, Brunauer-Emmer-Teller surface area analysis and electrochemical measurements. With the increase of pyrolyzing temperature and soaking time,the resin carbon material has larger crystallite sizes of Lc and La, lower specific surface area, smaller irreversible capacity and higher initial coulombic efficiency. The pyrolyzing temperature and soaking time are optimized to be 1050℃ and 2 h. The resin carbon anode obtained under the optimum conditions shows good electrochemical performances with reversible capacity of 387 mA · h/g and initial coulombic efficiency of 69.1%.

  14. Optimal Design of Wind-PV-Diesel-Battery System using Genetic Algorithm

    Science.gov (United States)

    Suryoatmojo, Heri; Hiyama, Takashi; Elbaset, Adel A.; Ashari, Mochamad

    Application of diesel generators to supply the load demand on isolated islands in Indonesia has widely spread. With increases in oil price and the concerns about global warming, the integration of diesel generators with renewable energy systems have become an attractive energy sources for supplying the load demand. This paper performs an optimal design of integrated system involving Wind-PV-Diesel-Battery system for isolated island with CO2 emission evaluation by using genetic algorithm. The proposed system has been designed for the hybrid power generation in East Nusa Tenggara, Indonesia-latitude 09.30S, longitude 122.0E. From simulation results, the proposed system is able to minimize the total annual cost of the system under study and reduce CO2 emission generated by diesel generators.

  15. Thorium conversion optimization in two-fluid molten-salt reactor

    International Nuclear Information System (INIS)

    Molten-Salt Reactors (MSR) are an attractive reactor system for various purposes. They can be designed to be operated in a fast neutron spectrum for spent fuel transmutation or in a thermal spectrum. Thermal MSRs provide an ideal platform for conversion of thorium to 233U. Flowing salt can be continuously reprocessed to minimize neutron losses due to neutron absorption in fission products. This study deals with a static neutronic optimization of a Two-Fluid MSR concept. Such a reactor features two separated molten-salt streams in the reactor core. One salt contains fissile material 233U, the other thorium. Separation of these streams improves the conversion capabilities of MSRs. Such a design was analysed for Molten-Salt Breeder Reactor (MSBR) development. This reactor was not realized, but it is used as a reference for this study. Monte-Carlo code MCNP5 was used to model a simplified MSBR core and for calculation of the breeding capabilities of this design. Several basic geometric parameters were selected for evaluation of their effect on characteristics of the reactor. Based on this analysis, an improved designed was prepared with shorter fissile material doubling time. The whole analysis was carried out for fresh fuel composition. It is possible to expect that on-line fuel reprocessing will limit fuel composition changes during reactor operation. Only effect of 233Pa accumulation on the thorium conversion was studied for several fuel reprocessing rates. (author)

  16. Maintenance optimization of the RP-10 reactor shutdown safety system

    International Nuclear Information System (INIS)

    This study examines the shutdown system of the 10 MW nuclear research reactor of the Instituto Peruano de Energia Nuclear (IPEN) in order to minimize the total cost with respect to the test interval. The total cost is comprised of the testing cost and the unsafe failure cost. The unsafe failure cost is evaluated as the expected cost of the consequences of the standby failure mode of the shutdown system, and the occurrence of a representative initial event which consist by an uncontrolled positive reactivity insertion during the start up. (author)

  17. Passive Safety Optimization in Liquid Sodium-Cooled Reactors

    International Nuclear Information System (INIS)

    The governing equations and the solutions schemes are developed for the three-dimensional thermal-hydraulic model.A detailed constitutive relations are also developed through the analysis with a CFD code. The developed model is able to obtain a detailed thermal hydraulic information in a subassemlby of a liquid metal-cooled reactor core. The model has been integrated with the system analysis codes SASSYS-1 and SSC-K to be validated for the SHRT-17 test performed in the EBR-II reactor. The baseline analyses were performed with the customary thermal-hydraulic model and with the new model for the reference design of KALIMER-150. The results point out that increased detail in the thermal-hydraulic analysis must be matched by increased detail in the reactivity feedback modeling, especially the radial core expansion model, in order to provide distinguishable differences. The analyses performed to identify certain key safety features have indicated that the adjustment of core restraint system is able to provide beneficial bending of hexcans, resulting in enhanced negative reactivity feedback in unprotected accidents. Tasks were performed to identify and assess the implications for plant safety of proposed specific approaches for reducing capital and operating costs of next generation sodium-cooled fast reactors. A new plant design of the sodium-cooled reactor concept is developed utilizing a gas turbine Brayton cycle, which uses supercritical carbon dioxide (S-CO2) as the working fluid. In addition, the design innovations are incorporated in modular sodium-to-supercritical carbon dioxide heat exchangers that enable the traditional intermediate heat transport circuit to be eliminated. Several evaluations and analyses for the safety design and efficiency suggest that the developed system is safe and cost-effective. Test plans are developed for the measurement of phenomenological data describing freezing of molten metallic fuel, melt relocation and interaction with steel

  18. Determination of the optimal positions for installing gamma ray detection systems at Tehran Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sayyah, A. [Department of Radiation Application, Shahid Beheshti University (Iran, Islamic Republic of); Rahmani, F., E-mail: FRahamni@kntu.ac.in [K.N. Toosi University of Technology, Department of Physics (Iran, Islamic Republic of); Khalafi, H. [Nuclear Science and Technology Research Institute (NSTRI) (Iran, Islamic Republic of)

    2015-09-01

    Dosimetric instruments must constantly monitor radiation dose levels in different areas of nuclear reactor. Tehran Research Reactor (TRR) has seven beam tubes for different research purposes. All the beam tubes extend from the reactor core to Beam Port Floor (BPF) of the reactor facility. During the reactor operation, the gamma rays exiting from each beam tube outlet produce a specific gamma dose rate field in the space of the BPF. To effectively monitor the gamma dose rates on the BPF, gamma ray detection systems must be installed in optimal positions. The selection of optimal positions is a compromise between two requirements. First, the installation positions must possess largest gamma dose rates and second, gamma ray detectors must not be saturated in these positions. In this study, calculations and experimental measurements have been carried out to identify the optimal positions of the gamma ray detection systems. Eight three dimensional models of the reactor core and related facilities corresponding to eight scenarios have been simulated using MCNPX Monte Carlo code to calculate the gamma dose equivalent rate field in the space of the BPF. These facilities are beam tubes, thermal column, pool, BPF space filled with air, facilities such as neutron radiography facility, neutron powder diffraction facility embedded in the beam tubes as well as biological shields inserted into the unused beam tubes. According to the analysis results of the combined gamma dose rate field, three positions on the north side and two positions on the south side of the BPF have been recognized as optimal positions for installing the gamma ray detection systems. To ensure the consistency of the simulation data, experimental measurements were conducted using TLDs (600 and 700) pairs during the reactor operation at 4.5 MW.

  19. Optimized Sizing, Selection, and Economic Analysis of Battery Energy Storage for Grid-Connected Wind-PV Hybrid System

    Directory of Open Access Journals (Sweden)

    Hina Fathima

    2015-01-01

    Full Text Available Energy storages are emerging as a predominant sector for renewable energy applications. This paper focuses on a feasibility study to integrate battery energy storage with a hybrid wind-solar grid-connected power system to effectively dispatch wind power by incorporating peak shaving and ramp rate limiting. The sizing methodology is optimized using bat optimization algorithm to minimize the cost of investment and losses incurred by the system in form of load shedding and wind curtailment. The integrated system is then tested with an efficient battery management strategy which prevents overcharging/discharging of the battery. In the study, five major types of battery systems are considered and analyzed. They are evaluated and compared based on technoeconomic and environmental metrics as per Indian power market scenario. Technoeconomic analysis of the battery is validated by simulations, on a proposed wind-photovoltaic system in a wind site in Southern India. Environmental analysis is performed by evaluating the avoided cost of emissions.

  20. Optimization of tritium breeding and shielding analysis to plasma in ITER fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Indah Rosidah, M., E-mail: indah.maymunah@gmail.com; Suud, Zaki, E-mail: szaki@fi.itb.ac.id [Department of Nuclear Physics, Faculty of Mathematic and Natural Sciences, Institut Teknologi Bandung (Indonesia); Yazid, Putranto Ilham [Research and Development of Nuclear Association (Indonesia)

    2015-09-30

    The development of fusion energy is one of the important International energy strategies with the important milestone is ITER (International Thermonuclear Experimental Reactor) project, initiated by many countries, such as: America, Europe, and Japan who agreed to set up TOKAMAK type fusion reactor in France. In ideal fusion reactor the fuel is purely deuterium, but it need higher temperature of reactor. In ITER project the fuels are deuterium and tritium which need lower temperature of the reactor. In this study tritium for fusion reactor can be produced by using reaction of lithium with neutron in the blanket region. With the tritium breeding blanket which react between Li-6 in the blanket with neutron resulted from the plasma region. In this research the material used in each layer surrounding the plasma in the reactor is optimized. Moreover, achieving self-sufficiency condition in the reactor in order tritium has enough availability to be consumed for a long time. In order to optimize Tritium Breeding Ratio (TBR) value in the fusion reactor, there are several strategies considered here. The first requirement is making variation in Li-6 enrichment to be 60%, 70%, and 90%. But, the result of that condition can not reach TBR value better than with no enrichment. Because there is reduction of Li-7 percent when increasing Li-6 percent. The other way is converting neutron multiplier material with Pb. From this, we get TBR value better with the Be as neutron multiplier. Beside of TBR value, fusion reactor can analyze the distribution of neutron flux and dose rate of neutron to know the change of neutron concentration for each layer in reactor. From the simulation in this study, 97% neutron concentration can be absorbed by material in reactor, so it is good enough. In addition, it is required to analyze spectrum neutron energy in many layers in the fusion reactor such as in blanket, coolant, and divertor. Actually material in that layer can resist in high temperature

  1. Contribution to the optimization of the coupling of nuclear reactors to desalination processes

    International Nuclear Information System (INIS)

    This work deals with modelling, simulation and optimization of the coupling between nuclear reactors (PWR, modular high temperature reactors) and desalination processes (multiple effect distillation, reverse osmosis). The reactors considered in this study are PWR (Pressurized Water Reactor) and GTMHR (Gas Turbine Modular Helium Reactor). The desalination processes retained are MED (Multi Effect Distillation) and SWRO (Sea Water Reverse Osmosis). A software tool: EXCELEES of thermodynamic modelling of coupled systems, based on the Engineering Algebraic Equation Solver has been developed. Models of energy conversion systems and of membrane desalination processes and distillation have been developed. Based on the first and second principles of thermodynamics, these models have allowed to determine the optimal running point of the coupled systems. The thermodynamic analysis has been completed by a first economic evaluation. Based on the use of the DEEP software of the IAEA, this evaluation has confirmed the interest to use these types of reactors for desalination. A modelling tool of thermal processes of desalination in dynamic condition has been developed too. This tool has been applied to the study of the dynamics of an existing plant and has given satisfying results. A first safety checking has been at last carried out. The transients able to jeopardize the integrated system have been identified. Several measures aiming at consolidate the safety have been proposed. (O.M.)

  2. Optimal axial enrichment distribution of the boiling water reactor fuel under the Haling strategy

    International Nuclear Information System (INIS)

    The axial enrichment distribution of boiling water reactor fuel is optimized to improve uranium utilization subject to constraints on thermal margins. It is assumed that the reactor is operated under the Haling strategy, so that determination of the enrichment distribution can be decoupled from the poison management. This nonlinear optimization problem is solved using a method of approximation programming, where each iteration step is formulated in terms of linear goal programming to handle infeasible problems. The core is represented by an axial one-dimensional model. The average enrichment of a two-region fuel can be slightly reduced by increasing the enrichment of the lower half rather than the upper half. The optimal solutions for a 24-region fuel, in which the enrichments of indivdual nodes can differ from one another, display double-humped enrichment distributions. The natural uranium blanket design is also investigated, and it is concluded that blanketed fuel is practically optimal using the Haling strategy

  3. Evaluation of Anaerobic Biofilm Reactor Kinetic Parameters Using Ant Colony Optimization.

    Science.gov (United States)

    Satya, Eswari Jujjavarapu; Venkateswarlu, Chimmiri

    2013-09-01

    Fixed bed reactors with naturally attached biofilms are increasingly used for anaerobic treatment of industry wastewaters due their effective treatment performance. The complex nature of biological reactions in biofilm processes often poses difficulty in analyzing them experimentally, and mathematical models could be very useful for their design and analysis. However, effective application of biofilm reactor models to practical problems suffers due to the lack of knowledge of accurate kinetic models and uncertainty in model parameters. In this work, an inverse modeling approach based on ant colony optimization is proposed and applied to estimate the kinetic and film thickness model parameters of wastewater treatment process in an anaerobic fixed bed biofilm reactor. Experimental data of pharmaceutical industry wastewater treatment process are used to determine the model parameters as a consequence of the solution of the rigorous mathematical models of the process. Results were evaluated for different modeling configurations derived from the combination of mathematical models, kinetic expressions, and optimization algorithms. Analysis of results showed that the two-dimensional mathematical model with Haldane kinetics better represents the pharmaceutical wastewater treatment in the biofilm reactor. The mathematical and kinetic modeling of this work forms a useful basis for the design and optimization of industry wastewater treating biofilm reactors. PMID:24065871

  4. Utilization of niching methods of genetic algorithms in nuclear reactor problems optimization

    International Nuclear Information System (INIS)

    Genetic Algorithms (GAs) are biologically motivated adaptive systems which have been used, with good results, in function optimization. However, traditional GAs rapidly push an artificial population toward convergence. That is, all individuals in the population soon become nearly identical. Niching Methods allow genetic algorithms to maintain a population of diverse individuals. GAs that incorporate these methods are capable of locating multiple, optimal solutions within a single population. The purpose of this study is to test existing niching techniques and two methods introduced herein, bearing in mind their eventual application in nuclear reactor related problems, specially the nuclear reactor core reload one, which has multiple solutions. Tests are performed using widely known test functions and their results show that the new methods are quite promising, specially in real world problems like the nuclear reactor core reload. (author)

  5. Optimal Homogenization of Perfusion Flows in Microfluidic Bio-Reactors: A Numerical Study

    DEFF Research Database (Denmark)

    Okkels, Fridolin; Dufva, Martin; Bruus, Henrik

    2011-01-01

    In recent years, the interest in small-scale bio-reactors has increased dramatically. To ensure homogeneous conditions within the complete area of perfused microfluidic bio-reactors, we develop a general design of a continually feed bio-reactor with uniform perfusion flow. This is achieved...... by introducing a specific type of perfusion inlet to the reaction area. The geometry of these inlets are found using the methods of topology optimization and shape optimization. The results are compared with two different analytic models, from which a general parametric description of the design is obtained...... and tested numerically. Such a parametric description will generally be beneficial for the design of a broad range of microfluidic bioreactors used for, e. g., cell culturing and analysis and in feeding bio-arrays....

  6. Proceedings of the seminar on optimization technology of the use of G.A. Siwabessy Research Reactor

    International Nuclear Information System (INIS)

    Seminar on optimization technology of the use of G.A. Siwabessy research reactor was held on March 16, 1999 at the Multipurpose Reactor Center, Serpong, Indonesia. During the seminar, have presented 14 papers about activities or researches on reactor operation technology, use of G.A. Siwabessy research reactor, engineering and nuclear installation development, maintenance and quality assurances. The seminar was held as a tool for developing non-researcher functional workers

  7. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Science.gov (United States)

    Benaouadj, M.; Aboubou, A.; Ayad, M. Y.; Bahri, M.; Boucetta, A.

    2016-07-01

    In this work, an optimal control (under constraints) based on the Pontryagin's maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control.Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  8. Optimized core design and fuel management of a pebble-bed type nuclear reactor

    NARCIS (Netherlands)

    Boer, B.

    2009-01-01

    The core design of a pebble-bed type Very High Temperature Reactor (VHTR) is optimized, aiming for an increase of the coolant outlet temperature to 1000 C, while retaining its inherent safety features. The VHTR has been selected by the international Generation IV research initiative as one of the si

  9. Design and axial optimization of nuclear fuel for BWR reactors; Diseno y optimizacion axial de combustible nuclear para reactores BWR

    Energy Technology Data Exchange (ETDEWEB)

    Garcia V, M.A

    2006-07-01

    In the present thesis, the modifications made to the axial optimization system based on Tabu Search (BT) for the axial design of BWR fuel type are presented, developed previously in the Nuclear Engineering Group of the UNAM Engineering Faculty. With the modifications what is mainly looked is to consider the particular characteristics of the mechanical design of the GE12 fuel type, used at the moment in the Laguna Verde Nucleo electric Central (CNLV) and that it considers the fuel bars of partial longitude. The information obtained in this thesis will allow to plan nuclear fuel reloads with the best conditions to operate in a certain cycle guaranteeing a better yield and use in the fuel burnt, additionally people in charge in the reload planning will be favored with the changes carried out to the system for the design and axial optimization of nuclear fuel, which facilitate their handling and it reduces their execution time. This thesis this developed in five chapters that are understood in the following way in general: Chapter 1: It approaches the basic concepts of the nuclear energy, it describes the physical and chemical composition of the atoms as well as that of the uranium isotopes, the handling of the uranium isotope by means of the nuclear fission until arriving to the operation of the nuclear reactors. Chapter 2: The nuclear fuel cycle is described, the methods for its extraction, its conversion and its enrichment to arrive to the stages of the nuclear fuel management used in the reactors are described. Beginning by the radial design, the axial design and the core design of the nuclear reactor related with the fuel assemblies design. Chapter 3: the optimization methods of nuclear fuel previously used are exposed among those that are: the genetic algorithms method, the search methods based on heuristic rules and the application of the tabu search method, which was used for the development of this thesis. Chapter 4: In this part the used methodology to the

  10. Optimal Scheduling of Energy Storage System for Self-Sustainable Base Station Operation Considering Battery Wear-Out Cost

    Directory of Open Access Journals (Sweden)

    Yohwan Choi

    2016-06-01

    Full Text Available A self-sustainable base station (BS where renewable resources and energy storage system (ESS are interoperably utilized as power sources is a promising approach to save energy and operational cost in communication networks. However, high battery price and low utilization of ESS intended for uninterruptible power supply (UPS necessitates active utilization of ESS. This paper proposes a multi-functional framework of ESS using dynamic programming (DP for realizing a sustainable BS. We develop an optimal charging and discharging scheduling algorithm considering a detailed battery wear-out model to minimize operational cost as well as to prolong battery lifetime. Our approach significantly reduces total cost compared to the conventional method that does not consider battery wear-out. Extensive experiments for several scenarios exhibit that total cost is reduced by up to 70.6% while battery wear-out is also reduced by 53.6%. The virtue of the proposed framework is its wide applicability beyond sustainable BS and thus can be also used for other types of load in principle.

  11. Optimization of FACTS and battery systems for supporting wind integration; Einsatzoptimierung von FACTS und Batterieanlagen zur Unterstuetzung der Windintegration

    Energy Technology Data Exchange (ETDEWEB)

    Danesh Shakib, Arefeh

    2012-07-01

    In the future an increase of wind energy contribution for electricity generation in Germany is expected, especially regarding to the development of offshore wind farms. The fundamental difficulty lies in the optimum transfer of power for long distances using existing 380-kV voltage level. With the help of modern power electronics (FACTS) it is principally possible to influence the active power flow as well as the voltage stability. Another problem of using wind energy is the unpredictable character of the wind, which leads to a higher requirement of control power from the adjustable traditional power plants. Here, the application of modern high energy battery systems seems to be a meaningful possibility, in the case of the wind farms with a DC transmission concept. In this case, the existent voltage level can be used for the battery connection too. The present study considers the issues of the wind energy applications. The wind integration in the north and east regions requires a connection to the high voltage grid, but the number of available connection points in these regions is extremely low. The network topology of the German 380-kV grid will be simulated with the help of existing documents. For determining the optimal connection points of the planed offshore wind farms voltage stability analyses will be performed based on the simulated network. Thus, it is possible to compare the voltage behaviors of the available connection points with each other and to estimate the amount of the maximum active power injection, respectively. Furthermore, according to the network analysis with an additional wind injection, placement technologies of the FACTS devices will be developed and presented. Although the focus the studies is on static var compensators (SVC) and thyristor controlled compensators (TCSC), the methods can be used for other FACTS devices. To determine the optimum setting values of FACTS an optimal power flow problem will be formulated. Sensitivity analyses

  12. Finding an optimization of the plate element of Egyptian research reactor using genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    WAHED Mohamed; IBRAHIM Wesam; EFFAT Ahmed

    2008-01-01

    The second Egyptian research reactor ET-RR-2 went critical on the 27th of November 1997. The National Center of Nuclear Safety and Radiation Control (NCNSRC) has the responsibility of the evaluation and assessment of the safety of this reactor. The purpose of this paper is to present an approach to optimization of the fuel element plate.For an efficient search through the solution space we use a multi objective genetic algorithm which allows us to identify a set of Pareto optimal solutions providing the decision maker with the complete spectrum of optimal solutions with respect to the various targets. The aim of this paper is to propose a new approach for optimizing the fuel element plate in the reactor. The fuel element plate is designed with a view to improve reliability and lifetime and it is one of the most important elements during the shut down. In this present paper, we present a conceptual design approach for fuel element plate, in conjunction with a genetic algorithm to obtain a fuel plate that maximizes a fitness value to optimize the safety design of the fuel plate.

  13. Cost-based optimization of a nuclear reactor core design: a preliminary model

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner F.; Alves Filho, Hermes [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Inst. Politecnico. Dept. de Modelagem Computacional]. E-mails: wfsacco@iprj.uerj.br; halves@iprj.uerj.br; Pereira, Claudio M.N.A. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil). Div. de Reatores]. E-mail: cmnap@ien.gov.br

    2007-07-01

    A new formulation of a nuclear core design optimization problem is introduced in this article. Originally, the optimization problem consisted in adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the radial power peaking factor in a three-enrichment zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. Here, we address the same problem using the minimization of the fuel and cladding materials costs as the objective function, and the radial power peaking factor as an operational constraint. This cost-based optimization problem is attacked by two metaheuristics, the standard genetic algorithm (SGA), and a recently introduced Metropolis algorithm called the Particle Collision Algorithm (PCA). The two algorithms are submitted to the same computational effort and their results are compared. As the formulation presented is preliminary, more elaborate models are also discussed (author)

  14. Magnetic susceptibility as a direct measure of oxidation state in LiFePO4 batteries and cyclic water gas shift reactors.

    Science.gov (United States)

    Kadyk, Thomas; Eikerling, Michael

    2015-08-14

    The possibility of correlating the magnetic susceptibility to the oxidation state of the porous active mass in a chemical or electrochemical reactor was analyzed. The magnetic permeability was calculated using a hierarchical model of the reactor. This model was applied to two practical examples: LiFePO4 batteries, in which the oxidation state corresponds with the state-of-charge, and cyclic water gas shift reactors, in which the oxidation state corresponds to the depletion of the catalyst. In LiFePO4 batteries phase separation of the lithiated and delithiated phases in the LiFePO4 particles in the positive electrode gives rise to a hysteresis effect, i.e. the magnetic permeability depends on the history of the electrode. During fast charge or discharge, non-uniform lithium distributionin the electrode decreases the hysteresis effect. However, the overall sensitivity of the magnetic response to the state-of-charge lies in the range of 0.03%, which makes practical measurement challenging. In cyclic water gas shift reactors, the sensitivity is 4 orders of magnitude higher and without phase separation, no hysteresis occurs. This shows that the method is suitable for such reactors, in which large changes of the magnetic permeability of the active material occurs. PMID:26156571

  15. Optimal battery sizing in photovoltaic based distributed generation using enhanced opposition-based firefly algorithm for voltage rise mitigation.

    Science.gov (United States)

    Wong, Ling Ai; Shareef, Hussain; Mohamed, Azah; Ibrahim, Ahmad Asrul

    2014-01-01

    This paper presents the application of enhanced opposition-based firefly algorithm in obtaining the optimal battery energy storage systems (BESS) sizing in photovoltaic generation integrated radial distribution network in order to mitigate the voltage rise problem. Initially, the performance of the original firefly algorithm is enhanced by utilizing the opposition-based learning and introducing inertia weight. After evaluating the performance of the enhanced opposition-based firefly algorithm (EOFA) with fifteen benchmark functions, it is then adopted to determine the optimal size for BESS. Two optimization processes are conducted where the first optimization aims to obtain the optimal battery output power on hourly basis and the second optimization aims to obtain the optimal BESS capacity by considering the state of charge constraint of BESS. The effectiveness of the proposed method is validated by applying the algorithm to the 69-bus distribution system and by comparing the performance of EOFA with conventional firefly algorithm and gravitational search algorithm. Results show that EOFA has the best performance comparatively in terms of mitigating the voltage rise problem.

  16. Optimal Battery Sizing in Photovoltaic Based Distributed Generation Using Enhanced Opposition-Based Firefly Algorithm for Voltage Rise Mitigation

    Directory of Open Access Journals (Sweden)

    Ling Ai Wong

    2014-01-01

    Full Text Available This paper presents the application of enhanced opposition-based firefly algorithm in obtaining the optimal battery energy storage systems (BESS sizing in photovoltaic generation integrated radial distribution network in order to mitigate the voltage rise problem. Initially, the performance of the original firefly algorithm is enhanced by utilizing the opposition-based learning and introducing inertia weight. After evaluating the performance of the enhanced opposition-based firefly algorithm (EOFA with fifteen benchmark functions, it is then adopted to determine the optimal size for BESS. Two optimization processes are conducted where the first optimization aims to obtain the optimal battery output power on hourly basis and the second optimization aims to obtain the optimal BESS capacity by considering the state of charge constraint of BESS. The effectiveness of the proposed method is validated by applying the algorithm to the 69-bus distribution system and by comparing the performance of EOFA with conventional firefly algorithm and gravitational search algorithm. Results show that EOFA has the best performance comparatively in terms of mitigating the voltage rise problem.

  17. μMORE: A microfluidic magnetic oscillation reactor for accelerated parameter optimization in biocatalysis.

    Science.gov (United States)

    Jussen, Daniel; Soltner, Helmut; Stute, Birgit; Wiechert, Wolfgang; von Lieres, Eric; Pohl, Martina

    2016-08-10

    Enzymatic parameter determination is an essential step in biocatalytic process development. Therefore higher throughput in miniaturized devices is urgently needed. An ideal microfluidic device should combine easy immobilization and retention of a minimal amount of biocatalyst with a well-mixed reaction volume. Together, all criteria are hardly met by current tools. Here we describe a microfluidic reactor (μMORE) which employs magnetic particles for both enzyme immobilization and efficient mixing using two permanent magnets placed in rotating cylinders next to the a glass chip reactor. The chip geometry and agitation speed was optimized by investigation of the mixing and retention characteristics using simulation and dye distribution analysis. Subsequently, the μMORE was successfully applied to determine critical biocatalytic process parameters in a parallelized manner for the carboligation of benzaldehyde and acetaldehyde to (S)-2-hydroxy-1-phenylpropan-1-one with less than 5μg of benzoylformate decarboxylase from Pseudomonas putida immobilized on magnetic beads. Here, one run of the device in six parallelized glass reactors took only 2-3h for an immobilized enzyme with very low activity (∼2U/mg). The optimized parameter set was finally tested in a 10mL enzyme membrane reactor, demonstrating that the μMORE provides a solid data base for biocatalytic process optimization. PMID:27288595

  18. Optimization and control of a novel upflow anaerobic solid-state (UASS) reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mumme, J.; Linke, B. [Leibniz Inst. for Agricultural Engineering, Potsdam (Germany); Tolle, R. [Humboldt Univ., Berlin (Germany). Dept. of Biosystems Technology

    2010-07-01

    Optimization and control strategies for a newly developed upflow anaerobic solid-state (UASS) reactor equipped with liquor recirculation were investigated. The UASS reactor converts solid biomass into biogas while the particulate organic matter (POM) ascends in the form of a solid-state bed (SSB) driven by the adherence of self-produced micro gas bubbles. Performance data and technical characteristics were obtained from a technical scale semi-automatic 400 L UASS reactor that operated for 117 days with maize silage under thermophilic conditions at 55 degrees C. The process liquor was continuously recirculated through separate methanogenic reactors in order to prevent an accumulation of volatile fatty acids. Emphasis was placed on determining the gas and metabolite production. The volatile solids (VS) loading rate was fixed at 5 g per litre per day. The methane production rate of the UASS reactor stabilized between 1.5 and 2.0 L per litre per day. The average volatile solids (VS) methane yield of the maize silage was 380 L per kg. The liquor exchange was found to play an important role in the performance and stability of the digestion process. Although low exchange rates can cause process failure by acidification, high exchange rates have the risk of clogging inside the SSB. It was concluded that the UASS reactor is a viable solution for the digestion of various organic matter.

  19. Optimization of the self-sufficient thorium fuel cycle for CANDU power reactors

    Directory of Open Access Journals (Sweden)

    Bergelson Boris R.

    2008-01-01

    Full Text Available The results of optimization calculations for CANDU reactors operating in the thorium cycle are presented in this paper. Calculations were performed to validate the feasibility of operating a heavy-water thermal neutron power reactor in a self-sufficient thorium cycle. Two modes of operation were considered in the paper: the mode of preliminary accumulation of 233U in the reactor itself and the mode of operation in a self-sufficient cycle. For the mode of accumulation of 233U, it was assumed that enriched uranium or plutonium was used as additional fissile material to provide neutrons for 233U production. In the self-sufficient mode of operation, the mass and isotopic composition of heavy nuclei unloaded from the reactor should provide (after the removal of fission products the value of the multiplication factor of the cell in the following cycle K>1. Additionally, the task was to determine the geometry and composition of the cell for an acceptable burn up of 233U. The results obtained demonstrate that the realization of a self-sufficient thorium mode for a CANDU reactor is possible without using new technologies. The main features of the reactor ensuring a self-sufficient mode of operation are a good neutron balance and moving of fuel through the active core.

  20. A new approach to nuclear reactor design optimization using genetic algorithms and regression analysis

    International Nuclear Information System (INIS)

    Highlights: • This paper presents a new method useful for the optimization of complex dynamic systems. • The method uses the strengths of; genetic algorithms (GA), and regression splines. • The method is applied to the design of a gas cooled fast breeder reactor design. • Tools like Java, R, and codes like MCNP, Matlab are used in this research. - Abstract: A module based optimization method using genetic algorithms (GA), and multivariate regression analysis has been developed to optimize a set of parameters in the design of a nuclear reactor. GA simulates natural evolution to perform optimization, and is widely used in recent times by the scientific community. The GA fits a population of random solutions to the optimized solution of a specific problem. In this work, we have developed a genetic algorithm to determine the values for a set of nuclear reactor parameters to design a gas cooled fast breeder reactor core including a basis thermal–hydraulics analysis, and energy transfer. Multivariate regression is implemented using regression splines (RS). Reactor designs are usually complex and a simulation needs a significantly large amount of time to execute, hence the implementation of GA or any other global optimization techniques is not feasible, therefore we present a new method of using RS in conjunction with GA. Due to using RS, we do not necessarily need to run the neutronics simulation for all the inputs generated from the GA module rather, run the simulations for a predefined set of inputs, build a multivariate regression fit to the input and the output parameters, and then use this fit to predict the output parameters for the inputs generated by GA. The reactor parameters are given by the, radius of a fuel pin cell, isotopic enrichment of the fissile material in the fuel, mass flow rate of the coolant, and temperature of the coolant at the core inlet. And, the optimization objectives for the reactor core are, high breeding of U-233 and Pu-239 in

  1. Possibilities to optimize sodium cooled fast reactors with respect to Actinide burning

    International Nuclear Information System (INIS)

    The optimization of fast reactor cores with respect to the destruction of Minor Actinides starts from the question, whether the neutron spectrum can be hardened by changing the core geometry, core size or fuel type. Spectrum hardening would increase the destruction (fission) of actinides compared to their further production due to capture processes. Reference point of this study is the European Fast Reactor EFR. It is shown that a flat core geometry with metal fuel would offer an optimum and that small power units, i. e. smaller cores are most favourable

  2. Preliminary Investigation of an Optimally Scramming Control Rod for Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    A passively safe control rod for gas-cooled reactors is proposed. This Optimally Scramming Control Rod (OSCR) is lifted out of the core region by the core coolant and descends back into the core when the coolant flow is not sufficient for core cooling purposes or in the event of depressurization. It is shown that for the current design of the OSCR, the reactor can be operated under normal lower power conditions down to about 80% of total power. It is also shown that cold shutdown can be achieved with rods of sufficiently low mass to allow naturally passive operation of the concept. (authors)

  3. Temperature Field Analysis and Thermal Dissipation Structure Optimization of Lithium-ion Battery Pack in PEVs

    OpenAIRE

    Hu Jianjun; Li Tao; Li Jing

    2014-01-01

    Aimed to achieve good thermal stability of lithium batteries in electric vehicles under the conditions of high-power. This study established a three-dimensional, transient heat dissipation model for Lithium-ion battery package in the three-dimensional Cartesian coordinate system based on theoretical knowledge of thermodynamics and heat transfer. With the help of the numerical simulation theoretical of CFD, the flow and temperature field of force air cooling Lithium-ion battery pack was simula...

  4. Fabrication and Optimization of Carbon Nanomaterial-Based Lithium-Ion Battery Anodes

    OpenAIRE

    Somnhot, Parina

    2012-01-01

    Lithium-ion batteries possess high energy and power densities, making them ideal candidates for energy storage requirements in various military applications. Commercially produced lithium-ion battery anodes are commonly graphitic carbon-based. However, graphitic carbons are limited in surface area and possess slow intercalation kinetics. The energy and power density demands of future technologies require improved lithium-ion battery performance. Carbon nanomaterials, such as carbide-derived c...

  5. Modelling and design optimization of low speed fuel cell - battery hybrid electric vehicles. Paper no. IGEC-1-125

    International Nuclear Information System (INIS)

    A push for electric vehicles has occurred in the past several decades due to various concerns about air pollution and the contribution of emissions to global climate change. Although electric cars and buses have been the focus of much of electric vehicle development, smaller vehicles are used extensively for transportation and utility purposes in many countries. In order to explore the viability of fuel cell - battery hybrid electric vehicles, empirical fuel cell system data has been incorporated into the NREL's vehicle design and simulation tool, ADVISOR (ADvanced Vehicle SimulatOR), to predict the performance of a low-speed, fuel cell - battery electric vehicle through MATLAB Simulink. The modelling and simulation provide valuable feedback to the design optimization of the fuel cell power system. A sampling based optimization algorithm was used to explore the viability and options of a low cost design for urban use. (author)

  6. Neutronic design analyses for a dual-coolant blanket concept: Optimization for a fusion reactor DEMO

    International Nuclear Information System (INIS)

    Highlights: ► Dual-Coolant He/Pb15.7Li breeding blanket for a DEMO fusion reactor is studied. ► An iterative process optimizes neutronic responses minimizing reactor dimension. ► A 3D toroidally symmetric geometry has been generated from the CAD model. ► Overall TBR values support the feasibility of the conceptual model considered. ► Power density in TF coils is below load limit for quenching. - Abstract: The generation of design specifications for a DEMO reactor, including breeding blanket (BB), vacuum vessel (VV) and magnetic field coils (MFC), requires a consistent neutronic optimization of structures between plasma and MFC. This work targets iteratively to generate these neutronic specifications for a Dual-Coolant He/Pb15.7Li breeding blanket design. The iteration process focuses on the optimization of allowable space between plasma scrapped-off-layer and VV in order to generate a MFC/VV/BB/plasma sustainable configuration with minimum global system volumes. Two VV designs have been considered: (1) a double-walled option with light-weight stiffeners and (2) a thick massive one. The optimization process also involves VV materials, looking to warrant radiation impact operational limits on the MFC. The resulting nuclear responses: peak nuclear heating in toroidal field (TF) coil, tritium breeding ratio (TBR), power amplification factor and helium production in the structural material are provided.

  7. Investigation of flow optimization in a compact reactor vessel of a FBR. Survey of flow optimization devices shape

    International Nuclear Information System (INIS)

    In the feasibility studies on Commercialized Fast Reactor Cycle Systems, a compact reactor vessel is investigated in terms of economical improvement of a sodium cooled loop type fast reactor. In order to compact reactor vessel, a simple fuel handling system is considered using 'a column type UIS (Upper Inner Structure) with a slit'. Gas entrainment due to high flow velocity in the UIS slit is one of major point of reactor vessel design. A 1/20th scaled model water experiment for reactor vessel upper plenum was performed to evaluate flow through a slit in the column type UIS, fundamental behavior of reactor upper plenum flow, and survey some devices which reduce flow velocity through the slit and optimize flow in the plenum. In the flow visualization tests, tracer particles were added to the water, and illuminated by the halogen lump light sheet. The flow visualized images were captured with a digital video camera. The visualization was done at a slit of UIS, opposite side of the UIS slit, front and side of hot leg (HL), front of slit and so on. We obtained fluid vertical velocity and fluctuation strength in the UIS slit using Ultrasound Velocity Profile monitor (UVP). The results are as follows. 1) In the test condition (Reynolds number; 2,500-5,000 at core outlet), flow field in the UIS slit was nearly identical in spite of core outlet velocity change. It is believed that this small scaled model test is adequate to see the flow pattern in the plenum and effect of the flow control devices. 2) An outer shroud was set on the UIS, which was perforated plate, and covered the UIS from middle to bottom except for the slit direction. The shroud had effects to bend the jet through the UIS slit toward the reactor vessel wall and also to flatten flow exiting from the UIS. 3) Flow guide was set beside of the slit of UIS baffle plate to reduce the jet velocity in the UIS slit using Coanda effect. The maximum effect was seen by using around shape guide. 4) There cylinders were

  8. A design scheme of control/optimization system for hybrid solar – wind and battery energy storages system

    OpenAIRE

    Singh, R.; Abbod, M; W. Balachandran

    2016-01-01

    This paper presents a design scheme of controlling – optimization system for solar – wind distribution renewable energy sources, its transmission, charging – discharging Battery Energy Storage System and connection to the grid distribution. The distribution renewable energy sources employs the Voltage Base Self – Intervention technique for solar – wind distribution renewable energy sources. The Hierarchical Switching Control Process technique is employed to switch, control, manage – supervise...

  9. A acore function for optimizing the cycle-life of battery-powered embedded systems

    NARCIS (Netherlands)

    Wognsen, Erik Ramsgaard; Haverkort, Boudewijn R.; Jongerden, Marijn; Hansen, René Rydhof; Larsen, Kim Guldstrand; Sankaranarayanan, Sriram; Vicario, Enrico

    2015-01-01

    An ever increasing share of embedded systems is powered by rechargeable batteries. These batteries deteriorate with the number of charge/discharge cycles they are subjected to, the so-called cycle life. In this paper, we propose the wear score function to compare and evaluate the relative impact of

  10. Jules Horowitz reactor. France development of an experimental loop integrating an optimized irradiation process

    International Nuclear Information System (INIS)

    Experimental reactors in the world enable researchers to meet the needs of industry and institutions not only by providing support to the existing nuclear infrastructure (Gen.2) but also by preparing the future generation (Gen.3, Gen.4) or even by responding to other needs as well (supports with fusion, medical applications). It is for this specific purpose that the Jules Horowitz Polyvalent Irradiation Reactor is now being built at the CEA Cadarache Research Center (located in the south of France). This Material Testing Reactor (MTR type) is designed to irradiate materials or fuel samples for various experimental tests. The reactor will also produce Mo99 radioelements that will supply 25% to 50% of current European needs. The goal of this paper is to describe a fuel irradiation loop, now under study, that will be designed to carry out power ramps tests to provide technical support to the Generation 2 and 3 nuclear power plants. In order to increase its irradiation capacity (2 to 3 per cycle), this loop takes into account the requirements that will lead to the optimization of all experimental processes in the facility (such as non-destructive examinations before and after the test, specific loading tools). All these considerations are being taken into account in order to offer to the customer's complete and optimized conditions in terms of experimental irradiations processes. (author)

  11. Fluid dynamic analysis of a continuous stirred tank reactor for technical optimization of wastewater digestion.

    Science.gov (United States)

    Hurtado, F J; Kaiser, A S; Zamora, B

    2015-03-15

    Continuous stirred tank reactors (CSTR) are widely used in wastewater treatment plants to reduce the organic matter and microorganism present in sludge by anaerobic digestion. The present study carries out a numerical analysis of the fluid dynamic behaviour of a CSTR in order to optimize the process energetically. The characterization of the sludge flow inside the digester tank, the residence time distribution and the active volume of the reactor under different criteria are determined. The effects of design and power of the mixing system on the active volume of the CSTR are analyzed. The numerical model is solved under non-steady conditions by examining the evolution of the flow during the stop and restart of the mixing system. An intermittent regime of the mixing system, which kept the active volume between 94% and 99%, is achieved. The results obtained can lead to the eventual energy optimization of the mixing system of the CSTR.

  12. A nuclear reactor core fuel reload optimization using Artificial-Ant-Colony Connective Networks

    International Nuclear Information System (INIS)

    A Pressurized Water Reactor core must be reloaded every time the fuel burnup reaches a level when it is not possible to sustain nominal power operation. The nuclear core fuel reload optimization consists in finding a burned-up and fresh-fuel-assembly pattern that maximizes the number of full operational days. This problem is NP-hard, meaning that complexity grows exponentially with the number of fuel assemblies in the core. Besides that, the problem is non-linear and its search space is highly discontinual and multimodal. In this work a parallel computational system based on Ant Colony System (ACS) called Artificial-Ant-Colony Networks is introduced to solve the nuclear reactor core fuel reload optimization problem. ACS is a system based on artificial agents that uses the reinforcement learning technique and was originally developed to solve the Traveling Salesman Problem, which is conceptually similar to the nuclear fuel reload problem. (author)

  13. Optimal homogenization of perfusion flows in microfluidic bio-reactors; a numerical study

    CERN Document Server

    Okkels, Fridolin; Bruus, Henrik

    2009-01-01

    To ensure homogeneous conditions within the complete area of perfused microfluidic bio-reactors, we develop a general design of a continuously feed bio-reactor with uniform perfusion flow. This is achieved by introducing a specific type of perfusion inlet to the reaction area. The geometry of these inlets are found using the methods of topology optimization and shape optimization. The results are compared with two different analytic models, from which a general parametric description of the design is obtained and tested numerically. Such a parametric description will generally be beneficial for the design of a broad range of microfluidic bioreactors used for e.g. cell culturing and analysis, and in feeding bio-arrays.

  14. Advanced CANDU reactors fuel analysis through optimal fuel management at approach to refuelling equilibrium

    International Nuclear Information System (INIS)

    The analysis of alternate CANDU fuels along with natural uranium-based fuel was carried out from the view point of optimal in-core fuel management at approach to refuelling equilibrium. The alternate fuels considered in the present work include thorium containing oxide mixtures (MOX), plutonium-based MOX, and Pressurised Water Reactor (PWR) spent fuel recycled in CANDU reactors (Direct Use of spent PWR fuel in CANDU (DUPIC)); these are compared with the usual natural UO2 fuel. The focus of the study is on the 'Approach to Refuelling Equilibrium' period which immediately follows the initial commissioning of the reactor. The in-core fuel management problem for this period is treated as an optimization problem in which the objective function is the refuelling frequency to be minimized by adjusting the following decision variables: the channel to be refuelled next, the time of the refuelling and the number of fresh fuel bundles to be inserted in the channel. Several constraints are also included in the optimisation problem which is solved using Perturbation Theory. Both the present 37-rod CANDU fuel bundle and the proposed CANFLEX bundle designs are part of this study. The results include the time to reach refuelling equilibrium from initial start-up of the reactor, the average discharge burnup, the average refuelling frequency and the average channel and bundle powers relative to natural UO2. The model was initially tested and the average discharge burnup for natural UO2 came within 2% of the industry accepted 199 MWh/kgHE. For this type of fuel, the optimization exercise predicted the savings of 43 bundles per full power year. In addition to producing average discharge burnups and other parameters for the advanced fuels investigated, the optimisation model also evidenced some problem areas like high power densities for fuels such as the DUPIC. Perturbation Theory has proven itself to be an accurate and valuable optimization tool in predicting the time between

  15. Optimized 4 pi spherical shell depleted uranium-water shield weights for 200 to 550-megawatt reactors

    Science.gov (United States)

    Wohl, M. L.; Celnik, J.; Schamberger, R. D.

    1972-01-01

    Optimization calculations to determine minimum 4 pi spherical-shell weights were performed at 200-, 375-, and 550-megawatt-thermal reactor power levels. Monte Carlo analyses were performed for a reactor power level corresponding to 375 megawatts. Power densities for the spherical reactor model used varied from 64.2 to 256 watts per cubic centimeter. The dose rate constraint in the optimization calculations was 0.25 mrem per hour at 9.14 meters from the reactor center. The resulting shield weights were correlated with the reactor power levels and power densities by a regression analysis. The optimum shield weight for a 375-megawatt, 160-watt-per-cubic-centimeter reactor was 202,000 kilograms.

  16. Development and optimization of a modified process for producing the battery grade LiOH: Optimization of energy and water consumption

    International Nuclear Information System (INIS)

    LiOH·H2O is used for preparation of alkaline batteries. The required characteristics of this compound are low levels of impurities and a specific particle size distribution. LiOH·H2O is produced from ore and brines. In northern Chile, lithium is produced from brines. This region presents particular desert climate conditions where water and energy are scarce. To help solve this problem, the conventional production process for battery grade LiOH·H2O was simulated and a modified process was developed, with an efficient consumption of energy and water, to improve the environmental sustainability of the plant, and greater process yield and product purity. Different configurations of the equipments were studied and for the best configurations the behavior of the modified process at different scenarios were simulated. It was found that the purity is independent of concentration used in feed to thickeners. The process yield increases in average 2.4% for modified process due to recycling operation. In modified process is obtained 28% more product mass, specific energy consumption decreases up to 4.8% and losses of Li/kg of product decreased by 83% compared to conventional process. The water consumption per kg of product in modified process is 1%–6.3%, being lower than in conventional process. The results presented can be considered as guidelines to address the optimization of the industrial process for obtaining the battery grade LiOH. - Highlights: • Water and energy are important resources in any sustainable industrial process. • High purity LiOH·H2O is a material for producing of lithium batteries. • Conventional and modified optimized processes for LiOH·H2O production were simulated. • Energy and water consumptions decrease for the modified process. • Optimal operational conditions of H2O, feed, pressure and energy were established

  17. Optimization of a Pd-based membrane reactor for hydrogen production from methane steam reforming

    Energy Technology Data Exchange (ETDEWEB)

    Assis, A.J.; Hori, C.E.; Silva, L.C.; Murata, V.V. [Universidade Federal de Uberlandia (UFU), MG (Brazil). School of Chemical Engineering]. E-mail: adilsonjassis@gmail.com

    2008-07-01

    In this work, it is proposed a phenomenological model in steady state to describe the performance of a membrane reactor for hydrogen production through methane steam reform as well as it is performed an optimization of operating conditions. The model is composed by a set of ordinary differential equations from mass, energy and momentum balances and constitutive relations. They were used two different intrinsic kinetic expressions from literature. The results predicted by the model were validated using experimental data. They were investigated the effect of five important process parameters, inlet reactor pressure (PR0), methane feed flow rate (FCH40), sweep gas flow rate (FI), external reactor temperature (TW) and steam to methane feed flow ratio (M), both on methane conversion (XCH{sub 4} ) and hydrogen recovery (YH{sub 2}). The best operating conditions were obtained through simple parametric optimization and by a method based on gradient, which uses the computer code DIRCOL in FORTRAN. It is shown that high methane conversion (96%) as well as hydrogen recovery (91%) can be obtained, using the optimized conditions. (author)

  18. Space and time optimization of nuclear reactors by means of the Pontryagin principle

    International Nuclear Information System (INIS)

    A numerical method is being presented for solving space dependent optimization problems concerning a functional for one dimensional geometries in the few group diffusion approximation. General dimensional analysis was applied to derive relations for the maximum of a functional and the limiting values of the constraints. Two procedures were given for calculating the anisotropic diffusion coefficients in order to improve the results of the diffusion approximation. In this work two procedures were presented for collapsing the microscopic multigroup cross sections, one general and another specific to the space dependent optimization problems solved by means of the Pontryagin maximum principle. Neutron spectrum optimization is performed to ensure the burnup of Pu239 isotope produced in a thermal nuclear reactor. A procedure is also given for the minimization of finite functional set by means of the Pontryagin maximum principle. A method for determining the characteristics of fission Pseudo products is formulated in one group and multigroup cases. This method is applied in the optimization of the burnup in nuclear reactors with fuel electric cells. A procedure to mjnimze the number of the fuel burnup equations is described. The optimization problems presented and solved in this work point to the efficiency of the maximum principle. Each problem on method presented in the various chapters is accompanied by considerations concerning dual problems and possibilities of further research development. (author)

  19. Evolutionary Strategy for Feeding Trajectory Optimization of Fed-batch Reactors

    Directory of Open Access Journals (Sweden)

    Tamás Varga

    2007-12-01

    Full Text Available Safe and optimal operation of complex production processes is one of the mostimportant research and development problems in process engineering. This problem is themost relevant at the design of the optimal feeding profile of fed-batch chemical reactorsdue to the nonlinear and unstable dynamical behavior of the processes. This paper showsthat how the optimal feeding policy can be determined in fed-batch reactors by sequentialquadratic programming, classical evolutionary strategy (ES and the advanced version ofES that is based on covariance matrix adaptation. A multi-objective function was createdand the search space was constrained in case of all of the three applied algorithms. Theswitching times between states in the feeding trajectory and the feed rates in each statewere manipulated to find the global minima of the objective function. To obtain the optimalfeeding policy the first-principle model of a pilot fed-batch reactor was implemented inMATLAB and applied as a dynamic simulator of the process. Off-line optimization processwas carried out in case of different dosing time distribution. As the results show asignificant improvement can be achieved in process performance applying advanced ESbased optimization algorithms to generate feeding trajectories.

  20. Optimization strategies for sustainable fuel cycle of the BR2 Reactor

    International Nuclear Information System (INIS)

    The objective of the present study is to achieve a sustainable fuel cycle in a long term of reactor operation applying advanced in-core loading strategies. The optimization criteria concern mainly enhancement of nuclear safety by means of reactivity margins and minimization of the operational fuel cycle cost at a given (constant) power level and same or longer cycle length. An important goal is also to maintain the same or to improve the experimental performances. Current developments are focused on optimization of control rods localization; optimization of fresh and burnt fuel assemblies in-core distribution; optimization of azimuth and axial fuel burn up strategies, including fuel assembly rotating and flipping upside down. (authors)

  1. Managing the process of catalytic reforming by the optimal distribution of temperature at the reactor block inlets

    OpenAIRE

    Левчук, Игорь Леонидович

    2015-01-01

    In this paper it is investigated an influence of the temperature of the reaction mixture at the inlets of a catalytic reforming reactor block on increment of aromatic hydrocarbons at outlets of separate reactors. It is found that for each reactor of a catalytic reforming exists some optimal temperature of the initial mixture from the standpoint of the increment of aromatics, which does not exceed a noticeable increase of flavoring materials, however, increases the rate of deactivation of the ...

  2. Development of a parallel genetic algorithm using MPI and its application in a nuclear reactor core. Design optimization

    International Nuclear Information System (INIS)

    This work presents the development of a distributed parallel genetic algorithm applied to a nuclear reactor core design optimization. In the implementation of the parallelism, a 'Message Passing Interface' (MPI) library, standard for parallel computation in distributed memory platforms, has been used. Another important characteristic of MPI is its portability for various architectures. The main objectives of this paper are: validation of the results obtained by the application of this algorithm in a nuclear reactor core optimization problem, through comparisons with previous results presented by Pereira et al.; and performance test of the Brazilian Nuclear Engineering Institute (IEN) cluster in reactors physics optimization problems. The experiments demonstrated that the developed parallel genetic algorithm using the MPI library presented significant gains in the obtained results and an accentuated reduction of the processing time. Such results ratify the use of the parallel genetic algorithms for the solution of nuclear reactor core optimization problems. (author)

  3. Magnesium based metal hydride reactor incorporating helical coil heat exchanger: Simulation study and optimal design

    International Nuclear Information System (INIS)

    Highlights: • A new 3D modeling for Mg-based metal hydride reactor is proposed. • Hydriding kinetics of Mg-based alloys is modeled based on the experimental data. • Helical coil heat exchanger has better heat transfer effect than traditional one. • The reactor with smaller non-dimensional pitch has favorable performance. - Abstract: Magnesium based metal hydride has been viewed as one of the most commonly-used materials in the practical applications of hydrogen energy systems. The heat and mass transfer processes have significant effects on the hydrogen storage performance of magnesium based metal hydride reactors. Incorporating helical coil heat exchanger into the reactor could be an effective way to improve the performance of heat and mass transfer. In this work, a new three-dimensional model for magnesium based metal hydride reactor with helical coil heat exchanger is proposed and solved using the commercial software package COMSOL Multiphysics V3.5a. The comparison of hydrogen storage behaviors between the reactors incorporating the traditional straight pipe and new helical coil heat exchangers is firstly conducted based on the numerical simulation. The comparison results show that the helical coil heat exchanger has better effect on improving the characteristics of reactor than the straight pipe heat exchanger due to its secondary circulation. The effects of key parameters, including the initial conditions, heat transfer coefficients of heat transfer fluid and helical coil geometry on the characteristics of reactor with the helical coil heat exchanger are also analyzed systematically. It is discovered that larger initial hydrogen pressure and lower initial temperature are beneficial to the improvement of hydrogen absorption kinetics, because of the greater driving force for the hydriding reaction. The results of optimal design suggest that smaller non-dimensional pitch, the ratio of helical pitch to helical diameter, improves the heat and mass transfer

  4. A dynamic plug flow reactor model for a vanadium redox flow battery cell

    Science.gov (United States)

    Li, Yifeng; Skyllas-Kazacos, Maria; Bao, Jie

    2016-04-01

    A dynamic plug flow reactor model for a single cell VRB system is developed based on material balance, and the Nernst equation is employed to calculate cell voltage with consideration of activation and concentration overpotentials. Simulation studies were conducted under various conditions to investigate the effects of several key operation variables including electrolyte flow rate, upper SOC limit and input current magnitude on the cell charging performance. The results show that all three variables have a great impact on performance, particularly on the possibility of gassing during charging at high SOCs or inadequate flow rates. Simulations were also carried out to study the effects of electrolyte imbalance during long term charging and discharging cycling. The results show the minimum electrolyte flow rate needed for operation within a particular SOC range in order to avoid gassing side reactions during charging. The model also allows scheduling of partial electrolyte remixing operations to restore capacity and also avoid possible gassing side reactions during charging. Simulation results also suggest the proper placement for cell voltage monitoring and highlight potential problems associated with setting the upper charging cut-off limit based on the inlet SOC calculated from the open-circuit cell voltage measurement.

  5. Application of Genetic Algorithm methodologies in fuel bundle burnup optimization of Pressurized Heavy Water Reactor

    International Nuclear Information System (INIS)

    Highlights: • We study and compare Genetic Algorithms (GA) in the fuel bundle burnup optimization of an Indian Pressurized Heavy Water Reactor (PHWR) of 220 MWe. • Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are considered. • For the selected problem, Multi Objective GA performs better than Penalty Functions based GA. • In the present study, Multi Objective GA outperforms Penalty Functions based GA in convergence speed and better diversity in solutions. - Abstract: The work carried out as a part of application and comparison of GA techniques in nuclear reactor environment is presented in the study. The nuclear fuel management optimization problem selected for the study aims at arriving appropriate reference discharge burnup values for the two burnup zones of 220 MWe Pressurized Heavy Water Reactor (PHWR) core. Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are applied in this study. The study reveals, for the selected problem of PHWR fuel bundle burnup optimization, Multi Objective GA is more suitable than Penalty Functions based GA in the two aspects considered: by way of producing diverse feasible solutions and the convergence speed being better, i.e. it is capable of generating more number of feasible solutions, from earlier generations. It is observed that for the selected problem, the Multi Objective GA is 25.0% faster than Penalty Functions based GA with respect to CPU time, for generating 80% of the population with feasible solutions. When average computational time of fixed generations are considered, Penalty Functions based GA is 44.5% faster than Multi Objective GA. In the overall performance, the convergence speed of Multi Objective GA surpasses the computational time advantage of Penalty Functions based GA. The ability of Multi Objective GA in producing more diverse feasible solutions is a desired feature of the problem selected, that helps the

  6. Study and Evaluation of Innovative Fuel Handling Systems for Sodium-Cooled Fast Reactors: Fuel Handling Route Optimization

    OpenAIRE

    Franck Dechelette; Franck Morin; Guy Laffont; Gilles Rodriguez; Emmanuel Sanseigne; Sébastien Christin; Xavier Mognot; Aurélien Morcillo

    2014-01-01

    International audience The research for technological improvement and innovation in sodium-cooled fast reactor is a matter of concern in fuel handling systems in a view to perform a better load factor of the reactor thanks to a quicker fuelling/defueling process. An optimized fuel handling route will also limit its investment cost. In that field, CEA has engaged some innovation study either of complete FHR or on the optimization of some specific components. This paper presents the study of...

  7. Adapting computational optimization concepts from aeronautics to nuclear fusion reactor design

    Directory of Open Access Journals (Sweden)

    Baelmans M.

    2012-10-01

    Full Text Available Even on the most powerful supercomputers available today, computational nuclear fusion reactor divertor design is extremely CPU demanding, not least due to the large number of design variables and the hybrid micro-macro character of the flows. Therefore, automated design methods based on optimization can greatly assist current reactor design studies. Over the past decades, “adjoint methods” for shape optimization have proven their virtue in the field of aerodynamics. Applications include drag reduction for wing and wing-body configurations. Here we demonstrate that also for divertor design, these optimization methods have a large potential. Specifically, we apply the continuous adjoint method to the optimization of the divertor geometry in a 2D poloidal cross section of an axisymmetric tokamak device (as, e.g., JET and ITER, using a simplified model for the plasma edge. The design objective is to spread the target material heat load as much as possible by controlling the shape of the divertor, while maintaining the full helium ash removal capabilities of the vacuum pumping system.

  8. Pattern optimization of PWR reactor using hybrid parallel Artificial Bee Colony

    International Nuclear Information System (INIS)

    Highlights: • The flying direction of each bee is improved through combination of individual and community flying experience. • The probability of selecting food sources by onlooker is enhanced by roulette-wheel mechanism. • We used parallel computation to further improve the algorithm’s performance. • The computational performance of the new parallel hybrid algorithm shows a speedup of 4.63 on 6 processors. • The proposed optimization method is applied to the cycle length maximization of a VVER-1000 reactor. - Abstract: In this paper, we propose a core reloading of pressurized water reactors technique based on a hybrid Artificial Bee Colony (ABC) algorithm. Our approach integrates the merits of both ABC algorithm and Particle Swarm Optimization (PSO). The neighborhood search scheme of the algorithm is improved by location of personally encountered the most flowers and location of highest concentration of flowers explored by the intact swarm. The probability of selecting food sources by onlooker in the proposed algorithm is enhanced through using roulette-wheel mechanism. To address the drawback of most optimization algorithms, this method has been parallelized, so that the runtimes may be greatly reduced by using a multiprocessor computer cluster. The proposed optimization method is applied to the cycle length maximization of a VVER-1000 core. Simulation results show that the proposed ABC method could have the advantages of original ABC, and is capable of producing low cost, fast, and reasonably accurate solutions

  9. Biodiesel Production from Vegetable Oil over Plasma Reactor: Optimization of Biodiesel Yield using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Bambang Tri Nugroho

    2009-06-01

    Full Text Available Biodiesel production has received considerable attention in the recent past as a renewable fuel. The production of biodiesel by conventional transesterification process employs alkali or acid catalyst and has been industrially accepted for its high conversion and reaction rates. However for alkali catalyst, there may be risk of free acid or water contamination and soap formation is likely to take place which makes the separation process difficult. Although yield is high, the acids, being corrosive, may cause damage to the equipment and the reaction rate was also observed to be low. This research focuses on empirical modeling and optimization for the biodiesel production over plasma reactor. The plasma reactor technology is more promising than the conventional catalytic processes due to the reducing reaction time and easy in product separation. Copyright (c 2009 by BCREC. All Rights reserved.[Received: 10 August 2009, Revised: 5 September 2009, Accepted: 12 October 2009][How to Cite: I. Istadi, D.D. Anggoro, P. Marwoto, S. Suherman, B.T. Nugroho (2009. Biodiesel Production from Vegetable Oil over Plasma Reactor: Optimization of Biodiesel Yield using Response Surface Methodology. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1: 23-31. doi:10.9767/bcrec.4.1.23.23-31][How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.23.23-31

  10. Biodiesel Production from Vegetable Oil over Plasma Reactor: Optimization of Biodiesel Yield using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Istadi Istadi

    2009-06-01

    Full Text Available Biodiesel production has received considerable attention in the recent past as a renewable fuel. The production of biodiesel by conventional transesterification process employs alkali or acid catalyst and has been industrially accepted for its high conversion and reaction rates. However for alkali catalyst, there may be risk of free acid or water contamination and soap formation is likely to take place which makes the separation process difficult. Although yield is high, the acids, being corrosive, may cause damage to the equipment and the reaction rate was also observed to be low. This research focuses on empirical modeling and optimization for the biodiesel production over plasma reactor. The plasma reactor technology is more promising than the conventional catalytic processes due to the reducing reaction time and easy in product separation. Copyright (c 2009 by BCREC. All Rights reserved.[Received: 10 August 2009, Revised: 5 September 2009, Accepted: 12 October 2009][How to Cite: I. Istadi, D.D. Anggoro, P. Marwoto, S. Suherman, B.T. Nugroho (2009. Biodiesel Production from Vegetable Oil over Plasma Reactor: Optimization of Biodiesel Yield using Response Surface Methodology. Bulletin of Chemical Reaction Engineering and Catalysis, 4(1: 23-31.  doi:10.9767/bcrec.4.1.7115.23-31][How to Link/ DOI: http://dx.doi.org/10.9767/bcrec.4.1.7115.23-31 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/7115

  11. Optimization of pressurized water reactor shuffling by simulated annealing with heuristics

    International Nuclear Information System (INIS)

    Simulated-annealing optimization of reactor core loading patterns is implemented with support for design heuristics during candidate pattern generation. The SIMAN optimization module uses the advanced nodal method of SIMULATE-3 and the full cross-section detail of CASMO-3 to evaluate accurately the neutronic performance of each candidate, resulting in high-quality patterns. The use of heuristics within simulated annealing is explored. Heuristics improve the consistency of optimization results for both fast- and slow-annealing runs with no penalty from the exclusion of unusual candidates. Thus, the heuristic application of designer judgment during automated pattern generation is shown to be effective. The capability of the SIMAN module to find and evaluate families of loading patterns that satisfy design constraints and have good objective performance within practical run times is demonstrated. The use of automated evaluations of successive cycles to explore multicycle effects of design decisions is discussed

  12. Constructal optimization for a solid-gas reactor based on triangular element

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Entropy generation minimization for heat and mass transfer process in a solid-gas reactor is carried out based on constructal theory by using triangular elemental area. The aspect ratio of the triangular elemental area is optimized under constraint conditions. A number of optimal triangular elements are assembled to a new large rectangular area, which is optimised again. The procedure is repeated until the control-volume is covered, and the complete analytical results are obtained. The effects of some parameters on minimum entropy generation are analysed by nu-merical examples. The results show that smaller entropy generation can be ob-tained when the optimization for a given volume is carried out on the basis of tri-angular elements than those obtained on the basis of rectangular elements.

  13. The investigation for attaining the optimal yield of oil shale by integrating high temperature reactors

    International Nuclear Information System (INIS)

    This work presents a systemanalytical investigation and shows how far a high temperature reactor can be integrated for achieving the optimal yield of kerogen from oil shale. About 1/3 of the produced components must be burnt out in order to have the required high temperature process heat. The works of IGT show that the hydrogen gasification of oil shale enables not only to reach oil shale of higher quality but also allows to achieve a higher extraction quantity. For this reason a hydro-gasification process has been calculated in this work in which not only hydrogen is used as the gasification medium but also two high temperature reactors are integrated as the source of high temperature heat. (orig.)

  14. An approach using quantum ant colony optimization applied to the problem of nuclear reactors reload

    International Nuclear Information System (INIS)

    The basic concept behind the nuclear reactor fuel reloading problem is to find a configuration of new and used fuel elements, to keep the plant working at full power by the largest possible duration, within the safety restrictions. The main restriction is the power peaking factor, which is the limit value for the preservation of the fuel assembly. The QACOAlfa algorithm is a modified version of Quantum Ant Colony Optimization (QACO) proposed by Wang et al, which uses a new actualization method and a pseudo evaporation step. We examined the QACOAlfa behavior associated to physics of reactors code RECNOD when applied to this problem. Although the QACO have been developed for continuous functions, the binary model used in this work allows applying it to discrete problems, such as the mentioned above. (author)

  15. Rapid Determination of Optimal Conditions in a Continuous Flow Reactor Using Process Analytical Technology

    Directory of Open Access Journals (Sweden)

    Michael F. Roberto

    2013-12-01

    Full Text Available Continuous flow reactors (CFRs are an emerging technology that offer several advantages over traditional batch synthesis methods, including more efficient mixing schemes, rapid heat transfer, and increased user safety. Of particular interest to the specialty chemical and pharmaceutical manufacturing industries is the significantly improved reliability and product reproducibility over time. CFR reproducibility can be attributed to the reactors achieving and maintaining a steady state once all physical and chemical conditions have stabilized. This work describes the implementation of a smart CFR with univariate physical and multivariate chemical monitoring that allows for rapid determination of steady state, requiring less than one minute. Additionally, the use of process analytical technology further enabled a significant reduction in the time and cost associated with offline validation methods. The technology implemented for this study is chemistry and hardware agnostic, making this approach a viable means of optimizing the conditions of any CFR.

  16. An approach using quantum ant colony optimization applied to the problem of nuclear reactors reload

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcio H.; Lima, Alan M.M. de; Schirru, Roberto; Medeiros, J.A.C.C., E-mail: marciohenrique@lmp.ufrj.b, E-mail: schirru@lmp.ufrj.b, E-mail: canedo@lmp.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear. Lab. de Monitoramento de Processos

    2009-07-01

    The basic concept behind the nuclear reactor fuel reloading problem is to find a configuration of new and used fuel elements, to keep the plant working at full power by the largest possible duration, within the safety restrictions. The main restriction is the power peaking factor, which is the limit value for the preservation of the fuel assembly. The QACO{sub A}lfa algorithm is a modified version of Quantum Ant Colony Optimization (QACO) proposed by Wang et al, which uses a new actualization method and a pseudo evaporation step. We examined the QACO{sub A}lfa behavior associated to physics of reactors code RECNOD when applied to this problem. Although the QACO have been developed for continuous functions, the binary model used in this work allows applying it to discrete problems, such as the mentioned above. (author)

  17. Optimization of operational water chemistry for supercritical-water cooled reactor

    International Nuclear Information System (INIS)

    The paper summaries the experimental results obtained within the project 'PRAMEK'. The project is focused on the study of the compatibility of the construction material of fossil-fueled supercritical water cooled power plants and water chemistry, that is currently used and optimization the dosing of the chemical species to the working circuit. The experience from the project enables to evaluate the water chemistry for Supercritical water cooled reactor (SCWR) and the transfer of the operational experience to the operation of the future nuclear power plant. The used materials are candidate for the SCWR and used in the industrial scale in the Ledvice power plant (fossil fuelled) with the supercritical parameters of the medium. It illustrates the future behaviour in the SCWR plant. The influence of the irradiation will be tested in future within the supercritical water loop in the reactor LVR-15. (author)

  18. Optimizing Neutron Thermal Scattering Effects in very High Temperature Reactors. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Hawari, Ayman [North Carolina State Univ., Raleigh, NC (United States). Dept. of Nuclear Engineering; Ougouag, Abderrafi [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-07-08

    This project aims to develop a holistic understanding of the phenomenon of neutron thermalization in the VHTR. Neutron thermalization is dependent on the type and structure of the moderating material. The fact that the moderator (and reflector) in the VHTR is a solid material will introduce new and interesting considerations that do not apply in other (e.g. light water) reactors. The moderator structure is expected to undergo radiation induced changes as the irradiation (or burnup) history progresses. In this case, the induced changes in structure will have a direct impact on many properties including the neutronic behavior. This can be easily anticipated if one recognizes the dependence of neutron thermalization on the scattering law of the moderator. For the pebble bed reactor, it is anticipated that the moderating behavior can be tailored, e.g. using moderators that consist of composite materials, which could allow improved optimization of the moderator-to-fuel ratio.

  19. Further optimization studies of experimental dynamic responses measured on the HTGC Dragon reactor

    International Nuclear Information System (INIS)

    This report considers some measurements made of the dynamics of the HTGC Dragon reactor and the optimization of a mathematical model which represents the reactor, by altering the parameters until a least squares fit between the experimental responses and the mathematical model is obtained. The experimental information was processed in various ways. The experimental response to an impulse, step or periodic sine wave change in reactivity was processed as an impulse, step or periodic sine wave response respectively and compared with a similar response from the model. In other studies the result of a binary cross correlation experiment (effectively an impulse response input) was processed as a frequency response and this experimental frequency response was compared with the frequency response from the mathematical model. It was possible therefore to compare the optimum values of parameters, obtained for different forms of perturbing signal and for different methods of processing and to relate the optima obtained to the problem of parameter estimation. (author)

  20. Boiling Water Reactor Loading Pattern Optimization Using Simple Linear Perturbation and Modified Tabu Search Methods

    International Nuclear Information System (INIS)

    An automated system for designing a loading pattern (LP) for boiling water reactors (BWRs) given a reference LP and control rod (CR) sequence has been developed. This system employs the advanced nodal code SIMULATE-3 and a BWR LP optimization code FINELOAD-3, which uses a simple linear perturbation method and a modified Tabu search method to select potential optimized LP candidates. Both of these unique methods of FINELOAD-3 were developed to achieve an effective BWR LP optimization strategy and to have high computational efficiency. FINELOAD-3 also adjusts deep CR positions to compensate for the core reactivity deviation caused by fuel shuffling. The objective function is to maximize the end-of-cycle core reactivity while satisfying the specified thermal margins and cold shutdown margin constraints. This optimization system realized the practical application for real BWR LP design. Computer time needed to obtain an optimized LP for a typical BWR/5 octant core with 15 depletion steps is ∼4 h using an engineering workstation. This system was extensively tested for real BWR reload core designs and showed that the developed LPs using this system are equivalent or better than the manually optimized LPs

  1. Design optimization of backup seal for sodium cooled fast breeder reactor

    International Nuclear Information System (INIS)

    Highlights: ► Design arrived from fourteen geometric options by finite element analysis. ► Seal geometry, size, compression, contact pressure, stress and compression load optimized. ► Effects of reduced fluoroelastomer strength at 110 °C, strain rate and stress-softening incorporated. ► Ageing, friction, tolerances, batch-to-batch/production variations in fluoroelastomer considered. ► Procedure applicable to other elastomeric seals of Fast Breeder Reactors. -- Abstract: Design optimization of static, fluoroelastomer backup seals for the 500 MWe, Prototype Fast Breeder Reactor (PFBR) is depicted. 14 geometric variations of a solid trapezoidal cross-section were studied by finite element analysis (FEA) to arrive at a design with hollowness and double o-ring contours on the sealing face. The seal design with squeeze of 5 mm assures failsafe operation for at least 10 years under a differential pressure of 25 kPa and ageing influences of fluid (air), temperature (110 °C) and γ radiation (23 mGy/h) in reactor. Hybrid elements of 1 mm length, regular integration, Mooney–Rivlin material model and Poisson’s ratio of 0.493 were used in axisymmetric analysis scheme. Possible effects of reduced fluoroelastomer strength at 110 °C, ageing, friction, tolerances in reactor scale, testing conditions during FEA data generation and batch-to-batch/production variations in seal material were considered to ensure adequate safety margin at the end of design life. The safety margin and numerical prediction accuracy could be improved further by using properties of specimens extracted from seal. The approach is applicable to other low pressure, moderate temperature elastomeric sealing applications of PFBR, mostly operating under maximum strain of 50%.

  2. Research on ISFLA-Based Optimal Control Strategy for the Coordinated Charging of EV Battery Swap Station

    Directory of Open Access Journals (Sweden)

    Xueliang Huang

    2013-01-01

    Full Text Available As an important component of the smart grid, electric vehicles (EVs could be a good measure against energy shortages and environmental pollution. A main way of energy supply to EVs is to swap battery from the swap station. Based on the characteristics of EV battery swap station, the coordinated charging optimal control strategy is investigated to smooth the load fluctuation. Shuffled frog leaping algorithm (SFLA is an optimization method inspired by the memetic evolution of a group of frogs when seeking food. An improved shuffled frog leaping algorithm (ISFLA with the reflecting method to deal with the boundary constraint is proposed to obtain the solution of the optimal control strategy for coordinated charging. Based on the daily load of a certain area, the numerical simulations including the comparison of PSO and ISFLA are carried out and the results show that the presented ISFLA can effectively lower the peak-valley difference and smooth the load profile with the faster convergence rate and higher convergence precision.

  3. Operational experience and programmes for optimal utilization of the Nigeria Research Reactor-1

    International Nuclear Information System (INIS)

    The Nigeria Research Reactor-1 (NIRR-1) is the nation's first nuclear reactor and it is sited at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. It is a Miniature Neutron Source Reactor (MNSR) that attained criticality on February 03, 2004 and was licensed to operate at a maximum power of 31 kW three days a week in June 01, 2004. This presentation enumerates the measures put in place to ensure safe operation and adequate maintenance regime as well as the strategic plans for optimal utilization of the reactor. Some of these measures, which bothers on safe operation and sustainable maintenance culture that have been implemented include: strict adherence to the periodic preventive maintenance routines; standard procedures for pre-startup, startup and shut down procedures; provision of a quick access to reactor top to facilitate rapid response in case of emergency, especially in the case of rod-stuck incident. Similarly, on the basis of experience gained since the commissioning vis-a-vis the neutron flux spectrum characteristics of the MNSRs, experimental protocols are presented for the analysis of elements producing short-lived, medium-lived and long-lived activation products in geologic materials with negligible nuclear interferences especially for the analysis of Al in the presence of Si. Furthermore, research and development activities in core physics analysis and thermal hydraulics with regards to conversion from the current HEU core to a LEU core under the aegis of the IAEA Coordinated Research Project entitled 'Conversion of MNSR to LEU' are outlined. (author)

  4. Operational experience and programmes for optimal utilization of the Nigeria Research Reactor-1

    International Nuclear Information System (INIS)

    The Nigeria Research Reactor-1 (NIRR-1) is the nation's first nuclear reactor and it is sited at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. It is a Miniature Neutron Source Reactor (MNSR) that attained criticality on February 03, 2004 and was licensed to operate at a maximum power of 31 kW three days a week in June 01, 2004. This presentation enumerates the measures put in place to ensure safe operation and adequate maintenance regime as well as the strategic plans for optimal utilization of the reactor. Some of these measures, which bothers on safe operation and sustainable maintenance culture that have been implemented include: strict adherence to the periodic preventive maintenance routines; standard procedures for pre-startup, startup and shut down procedures; provision of a quick access to reactor top to facilitate rapid response in case of emergency, especially in the case of rod-stuck incident. Similarly, on the basis of experience gained since the commissioning vis-a-vis the neutron flux spectrum characteristics of the MNSRs, experimental protocols are presented for the analysis of elements producing short-lived, medium-lived and long-lived activation products in geologic materials with negligible nuclear interferences especially for the analysis of Mg and Al in the presence of Al and Si respectively. Furthermore, research and development activities in core physics analysis and thermal hydraulics with regards to conversion from the current HEU core to a LEU core under the aegis of the IAEA Coordinated Research Project entitled 'Conversion of MNSR to LEU' are outlined. (author)

  5. A nuclear reactor core fuel reload optimization using artificial ant colony connective networks

    International Nuclear Information System (INIS)

    The core of a nuclear Pressurized Water Reactor (PWR) may be reloaded every time the fuel burn-up is such that it is not more possible to maintain the reactor operating at nominal power. The nuclear core fuel reload optimization problem consists in finding a pattern of burned-up and fresh-fuel assemblies that maximize the number of full operational days. This is an NP-Hard problem, meaning that complexity grows exponentially with the number of fuel assemblies in the core. Moreover, the problem is non-linear and its search space is highly discontinuous and multi-modal. Ant Colony System (ACS) is an optimization algorithm based on artificial ants that uses the reinforcement learning technique. The ACS was originally developed to solve the Traveling Salesman Problem (TSP), which is conceptually similar to the nuclear core fuel reload problem. In this work a parallel computational system based on the ACS, called Artificial Ant Colony Networks is introduced to solve the core fuel reload optimization problem

  6. A nuclear reactor core fuel reload optimization using artificial ant colony connective networks

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Alan M.M. de [Universidade Federal do Rio de Janeiro, PEN/COPPE - UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: alanmmlima@yahoo.com.br; Schirru, Roberto [Universidade Federal do Rio de Janeiro, PEN/COPPE - UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: schirru@lmp.ufrj.br; Carvalho da Silva, Fernando [Universidade Federal do Rio de Janeiro, PEN/COPPE - UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: fernando@con.ufrj.br; Medeiros, Jose Antonio Carlos Canedo [Universidade Federal do Rio de Janeiro, PEN/COPPE - UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: canedo@lmp.ufrj.br

    2008-09-15

    The core of a nuclear Pressurized Water Reactor (PWR) may be reloaded every time the fuel burn-up is such that it is not more possible to maintain the reactor operating at nominal power. The nuclear core fuel reload optimization problem consists in finding a pattern of burned-up and fresh-fuel assemblies that maximize the number of full operational days. This is an NP-Hard problem, meaning that complexity grows exponentially with the number of fuel assemblies in the core. Moreover, the problem is non-linear and its search space is highly discontinuous and multi-modal. Ant Colony System (ACS) is an optimization algorithm based on artificial ants that uses the reinforcement learning technique. The ACS was originally developed to solve the Traveling Salesman Problem (TSP), which is conceptually similar to the nuclear core fuel reload problem. In this work a parallel computational system based on the ACS, called Artificial Ant Colony Networks is introduced to solve the core fuel reload optimization problem.

  7. Optimization of Silicon parameters as a betavoltaic battery: Comparison of Si p-n and Ni/Si Schottky barrier

    Science.gov (United States)

    Rahmani, Faezeh; Khosravinia, Hossein

    2016-08-01

    Theoretical studies on the optimization of Silicon (Si) parameters as the base of betavoltaic battery have been presented using Monte Carlo simulations and the state equations in semiconductor to obtain maximum power. Si with active area of 1 cm2 has been considered in p-n junction and Schottky barrier structure to collect the radiation induced-charge from 10 mCi cm-2 of Nickle-63 (63Ni) Source. The results show that the betavoltaic conversion efficiency in the Si p-n structure is about 2.7 times higher than that in the Ni/Si Schottky barrier structure.

  8. Optimal Protection of Reactor Hall Under Nuclear Fuel Container Drop Using Simulation Methods

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2014-12-01

    Full Text Available This paper presents of the optimal design of the damping devices cover of reactor hall under impact of nuclear fuel container drop of type TK C30. The finite element idealization of nuclear power plant structure is used in software ANSYS. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall in comparison with the experimental results. The probabilistic and sensitivity analysis of the damping devices was considered on the base of the simulation methods in program AntHill using the Monte Carlo method.

  9. Feasibility Study and Techno-Economic Optimization Model for Battery Thermal Management System

    DEFF Research Database (Denmark)

    Khan, Mohammad Rezwan; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2014-01-01

    . Hence, the objective of this paper is to develop and detail the method of the feasibility for commissioning BTMS called “The decision tool frame-work” (DTF) and to investigate its sensitivity to major factors (e.g. lifetime and application requirement) which are well-known to influence the battery pack...... thermal performance, battery pack performance and ultimately the performance as well as utility of the desired application. This DTF is designed to provide a common frame-work of a BTMS manufacturer and designer to evaluate the options of different BTMS applicable for different applications and operating...

  10. Optimization of the cycle life performance of VRLA batteries, working under high rate, partial state of charge (HRPSOC) conditions

    Science.gov (United States)

    Fernández, M.; Trinidad, F.; Valenciano, J.; Sánchez, A.

    On hybrid vehicle applications, batteries must work in a rather low state of charge (SOC), in order to be able to recover as much of the regenerative braking energy as possible. Usually SOC values around 60% are used, which promotes the development of new unexpected failure modes not previously found, mainly associated with heavy sulphation of the negative plates. In order to try to optimise the cycle life performance to the point of making these batteries a real alternative for the application of hybrid vehicles, a series of tests have been undertaken, aimed to optimise the key parameters that from previous experience are known to determine life duration in high rate low state of charge (HRPSOC) conditions. Previous works have been focused on trying to determine the optimum composition of positive and negative active material, concerning paste density in the positive, and additives in negative. In order to overcome the deleterious effect of heavy sulphation in negative plates on cycle life, the use of conductivity enhancers additives such as graphite has been proposed. The objective of this project is to optimize the performance of the glass microfiber separators, in order to maintain a high degree of compression in the group, as well as to avoid acid stratification and development of short circuits along the battery life. To do this, different glass microfiber separators with inert additives, as well as different fiber composition have been tested. Results obtained up to now, indicate a remarkable good performance of the VRLA batteries with the new separators containing very fine fiberglass and silica fillers as an additive.

  11. A Power Smoothing Control Strategy and Optimized Allocation of Battery Capacity Based on Hybrid Storage Energy Technology

    Directory of Open Access Journals (Sweden)

    Yong Li

    2012-05-01

    Full Text Available Wind power parallel operation is an effective way to realize the large scale use of wind power, but the fluctuations of power output from wind power units may have great influence on power quality, hence a new method of power smoothing and capacity optimized allocation based on hybrid energy storage technology is proposed in terms of the uncontrollable and unexpected characteristics of wind speed in wind farms. First, power smoothing based on a traditional Inertial Filter is introduced and the relationship between the time constant, its smoothing effect and capacity allocation are analyzed and combined with Proportional Integral Differential (PID control to realize power smoothing control of wind power. Then wavelet theory is adopted to realize a multi-layer decomposition of power output in some wind farms, a power smoothing model based on hybrid energy storage technology is constructed combining the characteristics of the Super Capacitor (SC and Battery Energy Storage System (BESS technologies. The hybrid energy storage system is available for power fluctuations with high frequency-low energy and low frequency-high energy to achieve good smoothing effects compared with a single energy storage system. The power fluctuations filtered by the Wavelet Transform is regarded as the target value of BESS, the charging and discharging control for battery is completed quickly by Model Algorithm Control (MAC. Because of the influence of the inertia and the response speed of the battery, its actual output is not completely equal to the target value which mainly reflects in high-frequency part, the difference part uses SC to compensate and makes the output of battery and SC closer to the target value on the whole. Compared with the traditional Inertial Filter and PID control method, the validity of the model was verified by simulation results. Finally under the premise of power grid standards, the corresponding capacity design had been given to reduce the

  12. Development of methodology to optimize management of failed fuels in light water reactors

    International Nuclear Information System (INIS)

    Fuel cladding is one of the key components in a fission reactor that confines radioactive materials inside a fuel tube. During reactor operation, however, cladding is sometimes breached, and radioactive materials leak from the fuel pellet into the coolant water through the breach. The primary coolant water is therefore monitored so that any leak is quickly detected; coolant water is periodically sampled, and the concentration of radioactive iodine 131 (I-131), for example, is measured. Depending on the measured leakage concentration, the faulty fuel assembly with leaking rod is removed from the reactor and replaced immediately or at the next refueling. In the present study, an effort has been made to develop a methodology to optimize the management for replacement of faulty fuel assemblies due to cladding failures using measured leakage concentration. A model numerical equation is proposed to describe the time evolution of an increase in I-131 concentration due to cladding failures and is then solved using the Monte Carlo method as a function of sampling rate. Our results indicate that, to achieve rationalized management of failed fuels, higher resolution to detect a small amount of I-131 is not necessarily required, but more frequent sampling is favorable. (author)

  13. Assessing optimal fermentation type for bio-hydrogen production in continuous-flow acidogenic reactors.

    Science.gov (United States)

    Ren, N Q; Chua, H; Chan, S Y; Tsang, Y F; Wang, Y J; Sin, N

    2007-07-01

    In this study, the optimal fermentation type and the operating conditions of anaerobic process in continuous-flow acidogenic reactors was investigated for the maximization of bio-hydrogen production using mixed cultures. Butyric acid type fermentation occurred at pH>6, propionic acid type fermentation occurred at pH about 5.5 with E(h) (redox potential) >-278mV, and ethanol-type fermentation occurred at pHClostridium sp., Propionibacterium sp. and Bacteriodes sp., respectively. Ethanol fermentation was optimal type by comparing the operating stabilities and hydrogen production capacities between the fermentation types, which remained stable when the organic loading rate (OLR) reached the highest OLR at 86.1kgCOD/m(3)d. The maximum hydrogen production reached up to 14.99L/d.

  14. Optimal Utilization of Microgrids Supplemented with Battery Energy Storage Systems in Grid Support Applications

    DEFF Research Database (Denmark)

    Anvari-Moghaddam, Amjad; Dragicevic, Tomislav; Vasquez, Juan Carlos;

    2015-01-01

    This paper proposes a control scheme which minimizes the operating cost of a grid connected micro-grid supplemented by battery energy storage system (BESS). What distinguishes approach presented here from conventional strategies is that not only the price of electricity is considered...

  15. Optimizing MEMS-Based Storage Devices for Mobile Battery-Powered Systems

    NARCIS (Netherlands)

    Khatib, Mohammed G.; Hartel, Pieter H.

    2010-01-01

    An emerging storage technology, called MEMS-based storage, promises nonvolatile storage devices with ultrahigh density, high rigidity, a small form factor, and low cost. For these reasons, MEMS-based storage devices are suitable for battery-powered mobile systems such as PDAs. For deployment in such

  16. Optimal Sizing of a Stand-Alone Hybrid Power System Based on Battery/Hydrogen with an Improved Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    Weiqiang Dong

    2016-09-01

    Full Text Available A distributed power system with renewable energy sources is very popular in recent years due to the rapid depletion of conventional sources of energy. Reasonable sizing for such power systems could improve the power supply reliability and reduce the annual system cost. The goal of this work is to optimize the size of a stand-alone hybrid photovoltaic (PV/wind turbine (WT/battery (B/hydrogen system (a hybrid system based on battery and hydrogen (HS-BH for reliable and economic supply. Two objectives that take the minimum annual system cost and maximum system reliability described as the loss of power supply probability (LPSP have been addressed for sizing HS-BH from a more comprehensive perspective, considering the basic demand of load, the profit from hydrogen, which is produced by HS-BH, and an effective energy storage strategy. An improved ant colony optimization (ACO algorithm has been presented to solve the sizing problem of HS-BH. Finally, a simulation experiment has been done to demonstrate the developed results, in which some comparisons have been done to emphasize the advantage of HS-BH with the aid of data from an island of Zhejiang, China.

  17. Modeling the effect in of criticality from changes in key parameters for small High Temperature Nuclear Reactor (U-BatteryTM) using MCNP4C

    Science.gov (United States)

    Pauzi, A. M.

    2013-06-01

    The neutron transport code, Monte Carlo N-Particle (MCNP) which was wellkown as the gold standard in predicting nuclear reaction was used to model the small nuclear reactor core called "U-batteryTM", which was develop by the University of Manchester and Delft Institute of Technology. The paper introduces on the concept of modeling the small reactor core, a high temperature reactor (HTR) type with small coated TRISO fuel particle in graphite matrix using the MCNPv4C software. The criticality of the core were calculated using the software and analysed by changing key parameters such coolant type, fuel type and enrichment levels, cladding materials, and control rod type. The criticality results from the simulation were validated using the SCALE 5.1 software by [1] M Ding and J L Kloosterman, 2010. The data produced from these analyses would be used as part of the process of proposing initial core layout and a provisional list of materials for newly design reactor core. In the future, the criticality study would be continued with different core configurations and geometries.

  18. Safety-Related Optimization and Analyses of an Innovative Fast Reactor Concept

    Directory of Open Access Journals (Sweden)

    Dalin Zhang

    2012-06-01

    Full Text Available Since a fast reactor core with uranium-plutonium fuel is not in its most reactive configuration under operating conditions, redistribution of the core materials (fuel, steel, sodium during a core disruptive accident (CDA may lead to recriticalities and as a consequence to severe nuclear power excursions. The prevention, or at least the mitigation, of core disruption is therefore of the utmost importance. In the current paper, we analyze an innovative fast reactor concept developed within the CP-ESFR European project, focusing on the phenomena affecting the initiation and the transition phases of an unprotected loss of flow (ULOF accident. Key phenomena for the initiation phase are coolant boiling onset and further voiding of the core that lead to a reactivity increase in the case of a positive void reactivity effect. Therefore, the first level of optimization involves the reduction, by design, of the positive void effect in order to avoid entering a severe accident. If the core disruption cannot be avoided, the accident enters into the transition phase, characterized by the progression of core melting and recriticalities due to fuel compaction. Dedicated features that enhance and guarantee a sufficient and timely fuel discharge are considered for the optimization of this phase.

  19. Nuclear analysis and optimization of the molten-salt fusion hybrid reactor

    International Nuclear Information System (INIS)

    An improved method of studying the neutronic characteristics of fusion hybrid reactor blankets has been developed. Two major improvements over previous analysis methods have been accomplished. The first of these improvements is the introduction of one-dimensional, homogenized-region blanket neutronic models in which resonance and spatial self-shielding effects are treated explicitly. The second improvement involves the application of an iterative gradient-ascent based optimization scheme. In this method, key blanket dimensions and concentrations are automatically varied in a search for a configuration which maximizes neutronic performance. The specific fusion hybrid blanket design to which these new methods of analysis are applied in an evolution of the U-233 producing molten-salt-in-tubes concept studied by Lawrence Livermore National Laboratory (LLNL). Optimistic analysis techniques initially predicted the fissile fuel production capacity of this blanket to be 6400 kg of U-233 per year when driven by a 3000 MW tandem mirror fusion driver. The improved and more realistic analysis techniques employed in this study predict that an optimized molten-salt blanket design will produce over 6700 kg of U-233 per year when driven by the same tandem mirror device. Finally, the techniques and data base developed in this study have been designed to be easily extended to the task of performing future, more extensive analysis. Such an analysis might involve the minimization of fuel costs in an entire fusion hybrid reactor complex. 20 refs., 10 figs., 14 tabs

  20. The capacity of batch reactor optimation for mesophase from tarpitch based on fixed carbon and temperature dynamic analysis

    International Nuclear Information System (INIS)

    The process steps fiber graphite production with tarpitch as raw material are mesophase forming from tar pitch, fiber forming, carbon fiber forming and graphitization of fiber. The mesophase forming at 400 - 550°C so fixed carbon on the mesophase was getting 99.15 % from 98.9 % as fixed carbon on tar pitch. The first step of optimation is identification of graphite fiber capacity production with mesophase reactor capacity. The selection some mesophase reactor capacity, which is optimal, based on value change study of heating utility technical coefficient. The heating utility technical coefficient are Uc (overall heat transfer coefficient of clean condition), Ud (overall heat transfer coefficient of design) and Ar area of heat transfer in the mesophase reactor ). The result of calculation, more higher mesophase reactor capacity so the Uc is bigger but it is not for Ud dan Ar. The Ud dan Ar are effluence with the design condition. Based on the dynamic analysis for selected reactor 132,68 Ib/batch, 199 Ib/batch, 265 Ib/batch and 397,98 Ib/batch. The optimal capacity of mesophase reactor is 265 Ib/batch, it means plant capacity graphite fiber 100 ton/year. The dynamic analysis based on mass balance mathematical model and heat balance mathematical model. The numerical solution use matlab program. (author)

  1. An optimized process for tritium-containing waste water collection of High-Temperature Gas-cooled Reactor

    International Nuclear Information System (INIS)

    Highlights: • An optimized process for tritium-containing waste water collection of High-Temperature Gas-cooled Reactor was developed. • The optimized process and verification experiment using the HTR-10 were presented in detail. • A large quantity of high-dose tritium-containing waste water was successfully collected in commissioning experiment of the improved HTR-10. • The optimized process was proved to be reliable to avoid the large emission of radioactive waste water to the environment. - Abstract: An optimized process for tritium-containing waste water collection of High-Temperature Gas-cooled Reactor (HTGR) was developed and experimentally verified using the 10 MW High-Temperature Gas-cooled Reactor-test module (HTR-10). Compared with the previous process, an auxiliary molecular sieve bed was added in helium purification regeneration system and new operation process was proposed to collect tritium-containing waste water. In this paper, the optimized process and verification experiment were presented in detail. In commissioning experiment of the improved HTR-10, a large quantity of high-dose tritium-containing waste water was successfully collected in the water separator of helium purification regeneration system, with the specific activity being 6.1 × 109 Bq/L. The verification experiment confirms that the optimized process is effective and reliable for the demonstration plant design of High Temperature Gas-cooled Reactor-Pebble bed module (HTR-PM) to avoid the large emission of detrimentally radioactive waste water to the environment

  2. A binary mixed integer coded genetic algorithm for multi-objective optimization of nuclear research reactor fuel reloading

    Energy Technology Data Exchange (ETDEWEB)

    Binh, Do Quang [University of Technical Education Ho Chi Minh City (Viet Nam); Huy, Ngo Quang [University of Industry Ho Chi Minh City (Viet Nam); Hai, Nguyen Hoang [Centre for Research and Development of Radiation Technology, Ho Chi Minh City (Viet Nam)

    2014-12-15

    This paper presents a new approach based on a binary mixed integer coded genetic algorithm in conjunction with the weighted sum method for multi-objective optimization of fuel loading patterns for nuclear research reactors. The proposed genetic algorithm works with two types of chromosomes: binary and integer chromosomes, and consists of two types of genetic operators: one working on binary chromosomes and the other working on integer chromosomes. The algorithm automatically searches for the most suitable weighting factors of the weighting function and the optimal fuel loading patterns in the search process. Illustrative calculations are implemented for a research reactor type TRIGA MARK II loaded with the Russian VVR-M2 fuels. Results show that the proposed genetic algorithm can successfully search for both the best weighting factors and a set of approximate optimal loading patterns that maximize the effective multiplication factor and minimize the power peaking factor while satisfying operational and safety constraints for the research reactor.

  3. Bioleaching of uranium in batch stirred tank reactor: Process optimization using Box–Behnken design

    International Nuclear Information System (INIS)

    Highlights: ► High amount of uranium recovery achieved using Acidithiobacillus ferrooxidans. ► ANOVA shows individual variables and their squares are statistically significant. ► The model can accurately predict the behavior of uranium recovery. ► The model shows that pulp density has the greatest effect on uranium recovery. - Abstract: To design industrial reactors, it is important to identify and optimize the effective parameters of the process. Therefore, in this study, a three-level Box–Behnken factorial design was employed combining with a response surface methodology to optimize pulp density, agitation speed and aeration rate in uranium bioleaching in a stirred tank reactor using a pure native culture of Acidithiobacillus ferrooxidans. A mathematical model was then developed by applying the least squares method using the software Minitab Version 16.1.0. The second order model represents the uranium recovery as a function of pulp density, agitation speed and aeration rate. An analysis of variance was carried out to investigate the effects of individual variables and their combined interactive effects on uranium recovery. The results showed that the linear and quadratic terms of variables were statistically significant whilst the interaction terms were statistically insignificant. The model estimated that a maximum uranium extraction (99.99%) could be obtained when the pulp density, agitation speed and aeration rate were set at optimized values of 5.8% w/v, 510 rpm and 250 l/h, respectively. A confirmatory test at the optimum conditions resulted in a uranium recovery of 95%, indicating a marginal error of 4.99%. Furthermore, control tests were performed to demonstrate the effect of A. ferrooxidans in uranium bioleaching process and showed that the addition of this microorganism greatly increases the uranium recovery

  4. Studies on pressure losses and flow rate optimization in vanadium redox flow battery

    Science.gov (United States)

    Tang, Ao; Bao, Jie; Skyllas-Kazacos, Maria

    2014-02-01

    Premature voltage cut-off in the operation of the vanadium redox flow battery is largely associated with the rise in concentration overpotential at high state-of-charge (SOC) or state-of-discharge (SOD). The use of high constant volumetric flow rate will reduce concentration overpotential, although potentially at the cost of consuming excessive pumping energy which in turn lowers system efficiency. On the other hand, any improper reduction in flow rate will also limit the operating SOC and lead to deterioration in battery efficiency. Pressure drop losses are further exacerbated by the need to reduce shunt currents in flow battery stacks that requires the use of long, narrow channels and manifolds. In this paper, the concentration overpotential is modelled as a function of flow rate in an effort to determine an appropriate variable flow rate that can yield high system efficiency, along with the analysis of pressure losses and total pumping energy. Simulation results for a 40-cell stack under pre-set voltage cut-off limits have shown that variable flow rates are superior to constant flow rates for the given system design and the use of a flow factor of 7.5 with respect to the theoretical flow rate can reach overall high system efficiencies for different charge-discharge operations.

  5. Process optimization and kinetics for leaching of rare earth metals from the spent Ni-metal hydride batteries.

    Science.gov (United States)

    Meshram, Pratima; Pandey, B D; Mankhand, T R

    2016-05-01

    Nickel-metal hydride batteries (Ni-MH) contain not only the base metals, but valuable rare earth metals (REMs) viz. La, Sm, Nd, Pr and Ce as well. In view of the importance of resource recycling and assured supply of the contained metals in such wastes, the present study has focussed on the leaching of the rare earth metals from the spent Ni-MH batteries. The conditions for the leaching of REMs from the spent batteries were optimized as: 2M H2SO4, 348K temperature and 120min of time at a pulp density (PD) of 100g/L. Under this condition, the leaching of 98.1% Nd, 98.4% Sm, 95.5% Pr and 89.4% Ce was achieved. Besides the rare earth metals, more than 90% of base metals (Ni, Co, Mn and Zn) were also leached out in this condition. Kinetic data for the dissolution of all the rare earth metals showed the best fit to the chemical control shrinking core model. The leaching of metals followed the mechanism involving the chemical reaction proceeding on the surface of particles by the lixiviant, which was corroborated by the XRD phase analysis and SEM-EDS studies. The activation energy of 7.6, 6.3, 11.3 and 13.5kJ/mol was acquired for the leaching of neodymium, samarium, praseodymium and cerium, respectively in the temperature range 305-348K. From the leach liquor, the mixed rare earth metals were precipitated at pH∼1.8 and the precipitated REMs was analyzed by XRD and SEM studies to determine the phases and the morphological features. PMID:26746588

  6. A multi-level parallel computation of reactor cores using GPU for loading pattern optimization

    International Nuclear Information System (INIS)

    Efficient and rapid computation of multiple loading patterns using GPU is studied aiming application to loading pattern optimization of LWR. The loading pattern has significant impacts on safety and economy of a reactor. However, design of loading pattern is a combinatorial optimization problem, thus it is computationally intensive task. In order to address this issue, efficient and rapid computation method of loading patterns using massively parallel computing capability of GPU is studied in the present paper. Though GPU has higher computational performance than CPU, but different computational algorithm and coding approach are necessary to maximize the performance of GPU, due to different architecture of GPU. In the present study, a multi-level parallel computing approach is examined considering hardware architecture of GPU, i.e., parallel computing is carried out not only in spatial mesh-wise, but also in loading pattern-wise. In other words, multiple loading patterns are simultaneously computed and domain (mesh-wise) decomposition is applied to each loading pattern. With the present approach, computational efficiency using GPU is approximately four times higher than that of CPU. The present core analysis algorithm can be used for screening of poor loading patterns in optimization process. (author)

  7. Pebble Bed Reactors Design Optimization Methods and their Application to the Pebble Bed Fluoride Salt Cooled High Temperature Reactor (PB-FHR)

    Science.gov (United States)

    Cisneros, Anselmo Tomas, Jr.

    and PEBBED for a high temperature gas cooled pebble bed reactor. Three parametric studies were performed for exploring the design space of the PB-FHR---to select a fuel design for the PB-FHR] to select a core configuration; and to optimize the PB-FHR design. These parametric studies investigated trends in the dependence of important reactor performance parameters such as burnup, temperature reactivity feedback, radiation damage, etc on the reactor design variables and attempted to understand the underlying reactor physics responsible for these trends. A pebble fuel parametric study determined that pebble fuel should be designed with a carbon to heavy metal ratio (C/HM) less than 400 to maintain negative coolant temperature reactivity coefficients. Seed and thorium blanket-, seed and inert pebble reflector- and seed only core configurations were investigated for annular FHR PBRs---the C/HM of the blanket pebbles and discharge burnup of the thorium blanket pebbles were additional design variable for core configurations with thorium blankets. Either a thorium blanket or graphite pebble reflector is required to shield the outer graphite reflector enough to extend its service lifetime to 60 EFPY. The fuel fabrication costs and long cycle lengths of the thorium blanket fuel limit the potential economic advantages of using a thorium blanket. Therefore, the seed and pebble reflector core configuration was adopted as the baseline core configuration. Multi-objective optimization with respect to economics was performed for the PB-FHR accounting for safety and other physical design constraints derived from the high-level safety regulatory criteria. These physical constraints were applied along in a design tool, Nuclear Application Value Estimator, that evaluated a simplified cash flow economics model based on estimates of reactor performance parameters calculated using correlations based on the results of parametric design studies for a specific PB-FHR design and a set of

  8. Optimizing the determination of the neutrino mixing angle θ13 from reactor data

    Science.gov (United States)

    Khan, Amir N.; McKay, Douglas W.; Ralston, John P.

    2014-07-01

    The technical breakthroughs of multiple detectors developed by Daya Bay and RENO collaborations have gotten great attention. Yet the optimal determination of neutrino mixing parameters from reactor data depends on the statistical method and demands equal attention. We find that a straightforward method using minimal parameters will generally outperform a multi-parameter method by delivering more reliable values with sharper resolution. We review standard confidence levels and statistical penalties for models using extra parameters, and apply those rules to our analysis. We find that the methods used in recent work of the Daya Bay and RENO collaborations have several undesirable properties. The existing work also uses nonstandard measures of significance which we are unable to explain. A central element of the current methods consists of variationally fitting many more parameters than data points. As a result, the experimental resolution of sin2(2θ13) is degraded. The results also become extremely sensitive to certain model parameters that can be adjusted arbitrarily. The number of parameters to include in evaluating significance is an important issue that has generally been overlooked. The measures of significance applied previously would be consistent if and only if all parameters but one were considered to have no physical relevance for the experiment's hypothesis test. Simpler, more transparent methods can improve the determination of the mixing angle θ13 from reactor data, and exploit the advantages from superb hardware technique of the experiments. We anticipate that future experimental analysis will fully exploit those advantages.

  9. Preliminary optimization analysis of the radiation shielding of the China Lead-based Research Reactor

    International Nuclear Information System (INIS)

    Accelerator Driven subcritical System (ADS) is recognized as an efficient nuclear waste transmutation device. Supported by the Strategic Priority Research Program of 'the Future Advanced Nuclear Fission Energy-ADS transmutation system', the China LEAd-based Research Reactor (CLEAR-I) is proposed. Along with the approaching of the CLEAR-I design, the radiation shielding for CLEAR-I is updated and optimized step by step to meet with new shielding requirements. Employing the modeling program MCAM and calculation system VisualBUS developed by FDS Team, the shielding capability was verified using Monte Carlo method. As shown from the results, the fast neutron flux for components in reactor vessel is under the limitation and the neutron radiation for mechanism in containing room has been as low as possible. After shutdown for 7 days, the dose rate in most area of containing room is lower than 100 μSv/hr, allowing hands on operation. Replacement of components such as the spallation target in containing room is possible. (author)

  10. Design and optimization for the windowless target of the China Nuclear Waste Transmutation Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, De Sheng; Wang, Weihua; Yang, Shi Jun; Deng, Haifei; Wang, Rong Fei; Wang, Bin Jun [Institute Applied Physics of AOA, Hefei (China)

    2016-04-15

    A windowless spallation target can provide a neutron source and maintain neutron chain reaction for a subcritical reactor, and is a key component of China's nuclear waste transmutation of coupling accelerator and subcritical reactor. The main issue of the windowless target design is to form a stable and controllable free surface that can ensure that energy spectrum distribution is acquired for the neutron physical design when the high energy proton beam beats the lead-bismuth eutectic in the spallation target area. In this study, morphology and flow characteristics of the free surface of the windowless target were analyzed through the volume of fluid model using computational fluid dynamics simulation, and the results show that the outlet cross section size of the target is the key to form a stable and controllable free surface, as well as the outlet with an arc transition. The optimization parameter of the target design, in which the radius of outlet cross section is 60 ± 1 mm, is verified to form a stable and controllable free surface and to reduce the formation of air bubbles. This work can function as a reference for carrying out engineering design of windowless target and for verification experiments.

  11. Optimal Scheduling of a Battery Energy Storage System with Electric Vehicles’ Auxiliary for a Distribution Network with Renewable Energy Integration

    Directory of Open Access Journals (Sweden)

    Yuqing Yang

    2015-09-01

    Full Text Available With global conventional energy depletion, as well as environmental pollution, utilizing renewable energy for power supply is the only way for human beings to survive. Currently, distributed generation incorporated into a distribution network has become the new trend, with the advantages of controllability, flexibility and tremendous potential. However, the fluctuation of distributed energy resources (DERs is still the main concern for accurate deployment. Thus, a battery energy storage system (BESS has to be involved to mitigate the bad effects of DERs’ integration. In this paper, optimal scheduling strategies for BESS operation have been proposed, to assist with consuming the renewable energy, reduce the active power loss, alleviate the voltage fluctuation and minimize the electricity cost. Besides, the electric vehicles (EVs considered as the auxiliary technique are also introduced to attenuate the DERs’ influence. Moreover, both day-ahead and real-time operation scheduling strategies were presented under the consideration with the constraints of BESS and the EVs’ operation, and the optimization was tackled by a fuzzy mathematical method and an improved particle swarm optimization (IPSO algorithm. Furthermore, the test system for the proposed strategies is a real distribution network with renewable energy integration. After simulation, the proposed scheduling strategies have been verified to be extremely effective for the enhancement of the distribution network characteristics.

  12. Optimizing Reactors Selection and Sequencing:Minimum Cost versus Minimum Volume

    Institute of Scientific and Technical Information of China (English)

    Rachid Chebbi

    2014-01-01

    The present investigation targets minimum cost of reactors in series for the case of one single chemical reaction, considering plug flow and stirred tank reactor(s) in the sequence of flow reactors. Using Guthrie’s cost correlations three typical cases were considered based on the profile of the reaction rate reciprocal versus conversion. Significant differences were found compared to the classical approach targeting minimum total reactor volume.

  13. Heuristic optimization of a continuous flow point-of-use UV-LED disinfection reactor using computational fluid dynamics.

    Science.gov (United States)

    Jenny, Richard M; Jasper, Micah N; Simmons, Otto D; Shatalov, Max; Ducoste, Joel J

    2015-10-15

    Alternative disinfection sources such as ultraviolet light (UV) are being pursued to inactivate pathogenic microorganisms such as Cryptosporidium and Giardia, while simultaneously reducing the risk of exposure to carcinogenic disinfection by-products (DBPs) in drinking water. UV-LEDs offer a UV disinfecting source that do not contain mercury, have the potential for long lifetimes, are robust, and have a high degree of design flexibility. However, the increased flexibility in design options will add a substantial level of complexity when developing a UV-LED reactor, particularly with regards to reactor shape, size, spatial orientation of light, and germicidal emission wavelength. Anticipating that LEDs are the future of UV disinfection, new methods are needed for designing such reactors. In this research study, the evaluation of a new design paradigm using a point-of-use UV-LED disinfection reactor has been performed. ModeFrontier, a numerical optimization platform, was coupled with COMSOL Multi-physics, a computational fluid dynamics (CFD) software package, to generate an optimized UV-LED continuous flow reactor. Three optimality conditions were considered: 1) single objective analysis minimizing input supply power while achieving at least (2.0) log10 inactivation of Escherichia coli ATCC 11229; and 2) two multi-objective analyses (one of which maximized the log10 inactivation of E. coli ATCC 11229 and minimized the supply power). All tests were completed at a flow rate of 109 mL/min and 92% UVT (measured at 254 nm). The numerical solution for the first objective was validated experimentally using biodosimetry. The optimal design predictions displayed good agreement with the experimental data and contained several non-intuitive features, particularly with the UV-LED spatial arrangement, where the lights were unevenly populated throughout the reactor. The optimal designs may not have been developed from experienced designers due to the increased degrees of

  14. Electrolyte optimization and electrode material evaluation for the vanadium redox battery

    Science.gov (United States)

    Kazacos, Michael

    1990-05-01

    The preparation of the electrolyte for the all vanadium redox flow battery was investigated using both chemical and electrolytic reduction of V2O5 powder. Oxalic acid and SO2 reduction were found to be unsuitable as only the V(IV) state could be produced directly. With suspended powder hydrolysis, however, vanadium sulphate of any oxidation state, in this case 50 percent V(IV) plus 50 percent V(III) in sulphuric acid can readily be prepared from V2O5 powder, thus allowing a significant reduction in the cost of the vanadium battery electrolyte. Results from conductivity and electrolyte stability tests at elevated temperature have led to modification of the electrolyte composition for the vanadium redox cell, from the 2 M V plus 2 M H2SO4, originally employed, to the use of 3 M H2SO4, much higher energy efficiencies and greater electrolyte stability was demonstrated with the 3 M H2SO4 supporting electrolyte. Spectroscopy and electrolyte conductivity were demonstrated as suitable techniques for state-of-charge monitoring. A number of electrode materials were also evaluated and a Toray graphite bonded to a carbon plastic electrode was selected for further prototype development. Energy efficiencies of between 83 and 86 percent obtained for a current density of 30 mA/sq cm for a temperature range of 5 to 45 C, and between 0 and 100 percent state-of-charge. A wide range of construction materials was tested for long term stability in the vanadium redox electrolyte.

  15. Development of a multi-objective PBIL evolutionary algorithm applied to a nuclear reactor core reload optimization problem

    International Nuclear Information System (INIS)

    The nuclear reactor core reload optimization problem consists in finding a pattern of partially burned-up and fresh fuels that optimizes the plant's next operation cycle. This optimization problem has been traditionally solved using an expert's knowledge, but recently artificial intelligence techniques have also been applied successfully. The artificial intelligence optimization techniques generally have a single objective. However, most real-world engineering problems, including nuclear core reload optimization, have more than one objective (multi-objective) and these objectives are usually conflicting. The aim of this work is to develop a tool to solve multi-objective problems based on the Population-Based Incremental Learning (PBIL) algorithm. The new tool is applied to solve the Angra 1 PWR core reload optimization problem with the purpose of creating a Pareto surface, so that a pattern selected from this surface can be applied for the plant's next operation cycle. (author)

  16. Comparison of Ultra capacitors and Batteries Technologies to Optimize Hybrid Electric Vehicle Efficiency

    OpenAIRE

    Nzisabira, Jonathan; Louvigny, Yannick; Duysinx, Pierre

    2008-01-01

    The acceptance of Electric and Hybrid Electric Vehicle is related to their eco-efficiency, i.e. their ability to both reduce environmental impact while also providing a sufficient user satisfaction. The objective of this study is to provide a rationale design tool based on a multidisciplinary optimization approach to support the design of hybrid electric powertrain to simultaneously maximize user satisfaction complex criteria and minimize the Eco-score. In order to carry out the optimization ...

  17. Study and Evaluation of Innovative Fuel Handling Systems for Sodium-Cooled Fast Reactors: Fuel Handling Route Optimization

    Directory of Open Access Journals (Sweden)

    Franck Dechelette

    2014-01-01

    Full Text Available The research for technological improvement and innovation in sodium-cooled fast reactor is a matter of concern in fuel handling systems in a view to perform a better load factor of the reactor thanks to a quicker fuelling/defueling process. An optimized fuel handling route will also limit its investment cost. In that field, CEA has engaged some innovation study either of complete FHR or on the optimization of some specific components. This paper presents the study of three SFR fuel handling route fully described and compared to a reference FHR option. In those three FHR, two use a gas corridor to transfer spent and fresh fuel assembly and the third uses two casks with a sodium pot to evacuate and load an assembly in parallel. All of them are designed for the ASTRID reactor (1500 MWth but can be extrapolated to power reactors and are compatible with the mutualisation of one FHS coupled with two reactors. These three concepts are then intercompared and evaluated with the reference FHR according to four criteria: performances, risk assessment, investment cost, and qualification time. This analysis reveals that the “mixed way” FHR presents interesting solutions mainly in terms of design simplicity and time reduction. Therefore its study will be pursued for ASTRID as an alternative option.

  18. Optimal Operation and Management for Smart Grid Subsumed High Penetration of Renewable Energy, Electric Vehicle, and Battery Energy Storage System

    Science.gov (United States)

    Shigenobu, Ryuto; Noorzad, Ahmad Samim; Muarapaz, Cirio; Yona, Atsushi; Senjyu, Tomonobu

    2016-04-01

    Distributed generators (DG) and renewable energy sources have been attracting special attention in distribution systems in all over the world. Renewable energies, such as photovoltaic (PV) and wind turbine generators are considered as green energy. However, a large amount of DG penetration causes voltage deviation beyond the statutory range and reverse power flow at interconnection points in the distribution system. If excessive voltage deviation occurs, consumer's electric devices might break and reverse power flow will also has a negative impact on the transmission system. Thus, mass interconnections of DGs has an adverse effect on both of the utility and the customer. Therefore, reactive power control method is proposed previous research by using inverters attached DGs for prevent voltage deviations. Moreover, battery energy storage system (BESS) is also proposed for resolve reverse power flow. In addition, it is possible to supply high quality power for managing DGs and BESSs. Therefore, this paper proposes a method to maintain voltage, active power, and reactive power flow at interconnection points by using cooperative controlled of PVs, house BESSs, EVs, large BESSs, and existing voltage control devices. This paper not only protect distribution system, but also attain distribution loss reduction and effectivity management of control devices. Therefore mentioned control objectives are formulated as an optimization problem that is solved by using the Particle Swarm Optimization (PSO) algorithm. Modified scheduling method is proposed in order to improve convergence probability of scheduling scheme. The effectiveness of the proposed method is verified by case studies results and by using numerical simulations in MATLAB®.

  19. Optimization of power-cycle arrangements for Supercritical Water cooled Reactors (SCWRs)

    Science.gov (United States)

    Lizon-A-Lugrin, Laure

    The world energy demand is continuously rising due to the increase of both the world population and the standard of life quality. Further, to assure both a healthy world economy as well as adequate social standards, in a relatively short term, new energy-conversion technologies are mandatory. Within this framework, a Generation IV International Forum (GIF) was established by the participation of 10 countries to collaborate for developing nuclear power reactors that will replace the present technology by 2030. The main goals of these nuclear-power reactors are: economic competitiveness, sustainability, safety, reliability and resistance to proliferation. As a member of the GIF, Canada has decided to orient its efforts towards the design of a CANDU-type Super Critical Water-cooled Reactor (SCWR). Such a system must run at a coolant outlet temperature of about 625°C and at a pressure of 25 MPa. It is obvious that at such conditions the overall efficiency of this kind of Nuclear Power Plant (NPP) will compete with actual supercritical water-power boilers. In addition, from a heat-transfer viewpoint, the use of a supercritical fluid allows the limitation imposed by Critical Heat Flux (CHF) conditions, which characterize actual technologies, to be removed. Furthermore, it will be also possible to use direct thermodynamic cycles where the supercritical fluid expands right away in a turbine without the necessity of using intermediate steam generators and/or separators. This work presents several thermodynamic cycles that could be appropriate to run SCWR power plants. Improving both thermal efficiency and mechanical power constitutes a multi-objective optimization problem and requires specific tools. To this aim, an efficient and robust evolutionary algorithm, based on genetic algorithm, is used and coupled to an appropriate power plant thermodynamic simulation model. The results provide numerous combinations to achieve a thermal efficiency higher than 50% with a

  20. Optimization of coupled multiphysics methodology for safety analysis of pebble bed modular reactor

    Science.gov (United States)

    Mkhabela, Peter Tshepo

    The research conducted within the framework of this PhD thesis is devoted to the high-fidelity multi-physics (based on neutronics/thermal-hydraulics coupling) analysis of Pebble Bed Modular Reactor (PBMR), which is a High Temperature Reactor (HTR). The Next Generation Nuclear Plant (NGNP) will be a HTR design. The core design and safety analysis methods are considerably less developed and mature for HTR analysis than those currently used for Light Water Reactors (LWRs). Compared to LWRs, the HTR transient analysis is more demanding since it requires proper treatment of both slower and much longer transients (of time scale in hours and days) and fast and short transients (of time scale in minutes and seconds). There is limited operation and experimental data available for HTRs for validation of coupled multi-physics methodologies. This PhD work developed and verified reliable high fidelity coupled multi-physics models subsequently implemented in robust, efficient, and accurate computational tools to analyse the neutronics and thermal-hydraulic behaviour for design optimization and safety evaluation of PBMR concept The study provided a contribution to a greater accuracy of neutronics calculations by including the feedback from thermal hydraulics driven temperature calculation and various multi-physics effects that can influence it. Consideration of the feedback due to the influence of leakage was taken into account by development and implementation of improved buckling feedback models. Modifications were made in the calculation procedure to ensure that the xenon depletion models were accurate for proper interpolation from cross section tables. To achieve this, the NEM/THERMIX coupled code system was developed to create the system that is efficient and stable over the duration of transient calculations that last over several tens of hours. Another achievement of the PhD thesis was development and demonstration of full-physics, three-dimensional safety analysis

  1. 81.114- University Reactor Infrastructure and Education Support / Prompt Gamma-ray Activation Analysis of Lithioum Ion Battery Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Manthiram, Arumugam; Landsberger, S.

    2006-11-11

    This project focuses on the use of the Prompt Gamma-ray Activation Analysis (PGAA) technique available at the Nuclear Engineering Teaching Laboratory of the University of Texas at Austin to precisely determine the hydrogen (proton) contents in layered oxide cathode samples obtained by chemical lithium extraction in order to obtain a better understanding of the factors limiting the practical capacities and overall performance of lithium ion battery cathodes. The project takes careful precautionary experimental measures to avoid proton contamination both from solvents used in chemical delithiation and from ambient moisture. The results obtained from PGAA are complemented by the data obtained from other techniques such as thermogravimetric analysis, redox titration, atomic absorption spectroscopy, X-ray diffraction, and mass spectroscopic analysis of the evolved gas on heating. The research results broaden our understanding of the structure-property-performance relationships of lithium ion battery cathodes and could aid the design and development of new better performing lithium ion batteries for consumer (portable and electric vehicles), military, and space applications.

  2. Optimization of geometry, material and economic parameters of a two-zone subcritical reactor for transmutation of nuclear waste with SERPENT Monte Carlo code

    Science.gov (United States)

    Gulik, Volodymyr; Tkaczyk, Alan Henry

    2014-06-01

    An optimization study of a subcritical two-zone homogeneous reactor was carried out, taking into consideration geometry, material, and economic parameters. The advantage of a two-zone subcritical system over a single-zone system is demonstrated. The study investigated the optimal volume ratio for the inner and outer zones of the subcritical reactor, in terms of the neutron-physical parameters as well as fuel cost. Optimal geometrical parameters of the system are suggested for different material compositions.

  3. Improved Cyclability of Liquid Electrolyte Lithium/Sulfur Batteries by Optimizing Electrolyte/Sulfur Ratio

    Directory of Open Access Journals (Sweden)

    Sheng S. Zhang

    2012-12-01

    Full Text Available A liquid electrolyte lithium/sulfur (Li/S cell is a liquid electrochemical system. In discharge, sulfur is first reduced to highly soluble Li2S8, which dissolves into the organic electrolyte and serves as the liquid cathode. In solution, lithium polysulfide (PS undergoes a series of complicated disproportionations, whose chemical equilibriums vary with the PS concentration and affect the cell’s performance. Since the PS concentration relates to a certain electrolyte/sulfur (E/S ratio, there is an optimized E/S ratio for the cyclability of each Li/S cell system. In this work, we study the optimized E/S ratio by measuring the cycling performance of Li/S cells, and propose an empirical method for determination of the optimized E/S ratio. By employing an electrolyte of 0.25 m LiSO3CF3-0.25 m LiNO3 dissolved in a 1:1 (wt:wt mixture of dimethyl ether (DME and 1,3-dioxolane (DOL in an optimized E/S ratio, we show that the Li/S cell with a cathode containing 72% sulfur and 2 mg cm−2 sulfur loading is able to retain a specific capacity of 780 mAh g−1 after 100 cycles at 0.5 mA cm−2 between 1.7 V and 2.8 V.

  4. Optimization of biodiesel production in a hydrodynamic cavitation reactor using used frying oil.

    Science.gov (United States)

    Ghayal, Dyneshwar; Pandit, Aniruddha B; Rathod, Virendra K

    2013-01-01

    The present work demonstrates the application of a hydrodynamic cavitation reactor for the synthesis of biodiesel with used frying oil as a feedstock. The synthesis involved the transesterification of used frying oil (UFO) with methanol in the presence of potassium hydroxide as a catalyst. The effect of geometry and upstream pressure of a cavitating orifice plate on the rate of transesterification reaction has been studied. It is observed that the micro level turbulence created by hydrodynamic cavitation somewhat overcomes the mass transfer limitations for triphasic transesterification reaction. The significant effects of upstream pressure on the rate of formation of methyl esters have been seen. It has been observed that flow geometry of orifice plate plays a crucial role in process intensification. With an optimized plate geometry of 2mm hole diameter and 25 holes, more than 95% of triglycerides have been converted to methyl esters in 10 min of reaction time with cavitational yield of 1.28 × 10(-3) (Grams of methyl esters produced per Joule of energy supplied). The potential of UFO to produce good quality methyl esters has been demonstrated. PMID:22922070

  5. Automatic boiling water reactor loading pattern design using ant colony optimization algorithm

    International Nuclear Information System (INIS)

    An automatic boiling water reactor (BWR) loading pattern (LP) design methodology was developed using the rank-based ant system (RAS), which is a variant of the ant colony optimization (ACO) algorithm. To reduce design complexity, only the fuel assemblies (FAs) of one eight-core positions were determined using the RAS algorithm, and then the corresponding FAs were loaded into the other parts of the core. Heuristic information was adopted to exclude the selection of the inappropriate FAs which will reduce search space, and thus, the computation time. When the LP was determined, Haling cycle length, beginning of cycle (BOC) shutdown margin (SDM), and Haling end of cycle (EOC) maximum fraction of limit for critical power ratio (MFLCPR) were calculated using SIMULATE-3 code, which were used to evaluate the LP for updating pheromone of RAS. The developed design methodology was demonstrated using FAs of a reference cycle of the BWR6 nuclear power plant. The results show that, the designed LP can be obtained within reasonable computation time, and has a longer cycle length than that of the original design.

  6. Automatic boiling water reactor loading pattern design using ant colony optimization algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C.-D. [Department of Engineering and System Science, National Tsing Hua University, 101, Section 2 Kuang Fu Road, Hsinchu 30013, Taiwan (China); Nuclear Engineering Division, Institute of Nuclear Energy Research, No. 1000, Wenhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China)], E-mail: jdwang@iner.gov.tw; Lin Chaung [Department of Engineering and System Science, National Tsing Hua University, 101, Section 2 Kuang Fu Road, Hsinchu 30013, Taiwan (China)

    2009-08-15

    An automatic boiling water reactor (BWR) loading pattern (LP) design methodology was developed using the rank-based ant system (RAS), which is a variant of the ant colony optimization (ACO) algorithm. To reduce design complexity, only the fuel assemblies (FAs) of one eight-core positions were determined using the RAS algorithm, and then the corresponding FAs were loaded into the other parts of the core. Heuristic information was adopted to exclude the selection of the inappropriate FAs which will reduce search space, and thus, the computation time. When the LP was determined, Haling cycle length, beginning of cycle (BOC) shutdown margin (SDM), and Haling end of cycle (EOC) maximum fraction of limit for critical power ratio (MFLCPR) were calculated using SIMULATE-3 code, which were used to evaluate the LP for updating pheromone of RAS. The developed design methodology was demonstrated using FAs of a reference cycle of the BWR6 nuclear power plant. The results show that, the designed LP can be obtained within reasonable computation time, and has a longer cycle length than that of the original design.

  7. Optimization of biodiesel production in a hydrodynamic cavitation reactor using used frying oil.

    Science.gov (United States)

    Ghayal, Dyneshwar; Pandit, Aniruddha B; Rathod, Virendra K

    2013-01-01

    The present work demonstrates the application of a hydrodynamic cavitation reactor for the synthesis of biodiesel with used frying oil as a feedstock. The synthesis involved the transesterification of used frying oil (UFO) with methanol in the presence of potassium hydroxide as a catalyst. The effect of geometry and upstream pressure of a cavitating orifice plate on the rate of transesterification reaction has been studied. It is observed that the micro level turbulence created by hydrodynamic cavitation somewhat overcomes the mass transfer limitations for triphasic transesterification reaction. The significant effects of upstream pressure on the rate of formation of methyl esters have been seen. It has been observed that flow geometry of orifice plate plays a crucial role in process intensification. With an optimized plate geometry of 2mm hole diameter and 25 holes, more than 95% of triglycerides have been converted to methyl esters in 10 min of reaction time with cavitational yield of 1.28 × 10(-3) (Grams of methyl esters produced per Joule of energy supplied). The potential of UFO to produce good quality methyl esters has been demonstrated.

  8. Optimal configuration of power distribution of a research reactors by depleted uranium use

    International Nuclear Information System (INIS)

    A nuclear reactor project requires that the thermal power density distribution be as uniform as possible in order to minimize temperature peaks which limit the total power. This work describes the calculations aimed at determining an optimized distribution of depleted uranium in a graphite-moderated, air cooled cylindrical core loaded with natural uranium. Cross section calculations were performed with the Hammer code while 3D flux and power distributions were generated with the CITATION code. It has been found that the use of depleted uranium renders a more uniform flux and power distribution. The effect, which results from a decrease in the power density (and consequently, also in the temperature) in the hottest channels, allows the overall power to be further raised within the safety limits. In addition, the proposed method also provides a means to arbitrarily reduce the excess reactivity when necessary. Finally, it also leads to the creation of an over moderated region with higher thermal neutron fluxes which could be used for irradiation experiments. (author)

  9. Optimization of a whole-cell biocatalyst by employing genetically encoded product sensors inside nanolitre reactors

    Science.gov (United States)

    Meyer, Andreas; Pellaux, René; Potot, Sébastien; Becker, Katja; Hohmann, Hans-Peter; Panke, Sven; Held, Martin

    2015-08-01

    Microcompartmentalization offers a high-throughput method for screening large numbers of biocatalysts generated from genetic libraries. Here we present a microcompartmentalization protocol for benchmarking the performance of whole-cell biocatalysts. Gel capsules served as nanolitre reactors (nLRs) for the cultivation and analysis of a library of Bacillus subtilis biocatalysts. The B. subtilis cells, which were co-confined with E. coli sensor cells inside the nLRs, converted the starting material cellobiose into the industrial product vitamin B2. Product formation triggered a sequence of reactions in the sensor cells: (1) conversion of B2 into flavin mononucleotide (FMN), (2) binding of FMN by a RNA riboswitch and (3) self-cleavage of RNA, which resulted in (4) the synthesis of a green fluorescent protein (GFP). The intensity of GFP fluorescence was then used to isolate B. subtilis variants that convert cellobiose into vitamin B2 with elevated efficiency. The underlying design principles of the assay are general and enable the development of similar protocols, which ultimately will speed up the optimization of whole-cell biocatalysts.

  10. Optimization of reactor network design problem using Jumping Gene Adaptation of Differential Evolution

    Science.gov (United States)

    Gujarathi, Ashish M.; Purohit, S.; Srikanth, B.

    2015-06-01

    Detailed working principle of jumping gene adaptation of differential evolution (DE-JGa) is presented. The performance of the DE-JGa algorithm is compared with the performance of differential evolution (DE) and modified DE (MDE) by applying these algorithms on industrial problems. In this study Reactor network design (RND) problem is solved using DE, MDE, and DE-JGa algorithms: These industrial processes are highly nonlinear and complex with reference to optimal operating conditions with many equality and inequality constraints. Extensive computational comparisons have been made for all the chemical engineering problems considered. The results obtained in the present study show that DE-JGa algorithm outperforms the other algorithms (DE and MDE). Several comparisons are made among the algorithms with regard to the number of function evaluations (NFE)/CPU- time required to find the global optimum. The standard deviation and the variance values obtained using DE-JGa, DE and MDE algorithms also show that the DE-JGa algorithm gives consistent set of results for the majority of the test problems and the industrial real world problems.

  11. Comparison of Ultra Capacitors, Hydraulic Accumulators and Batteries Technologies to Optimize Hybrid Vehicle Ecoefficiency

    OpenAIRE

    Nzisabira, Jonathan; Louvigny, Yannick; Duysinx, Pierre

    2009-01-01

    The main objective of vehicle powertrain hybridization is to improve the fuel consumption and environment pollutants impact (Eco-score) without decreasing the vehicle performances and other user satisfaction criteria. The Eco efficiency is a global index which accounts for both environmental impacts and user satisfaction. The Hybrid vehicles ability to overcome these two requirements depends on the optimal choice of their key mechanical, electric or hydraulic components. Some energy storage ...

  12. Optimal Velocity Control for a Battery Electric Vehicle Driven by Permanent Magnet Synchronous Motors

    Directory of Open Access Journals (Sweden)

    Dongbin Lu

    2014-01-01

    Full Text Available The permanent magnet synchronous motor (PMSM has high efficiency and high torque density. Field oriented control (FOC is usually used in the motor to achieve maximum efficiency control. In the electric vehicle (EV application, the PMSM efficiency model, combined with the EV and road load system model, is used to study the optimal energy-saving control strategy, which is significant for the economic operation of EVs. With the help of GPS, IMU, and other information technologies, the road conditions can be measured in advance. Based on this information, the optimal velocity of the EV driven by PMSM can be obtained through the analytical algorithm according to the efficiency model of PMSM and the vehicle dynamic model in simple road conditions. In complex road conditions, considering the dynamic characteristics, the economic operating velocity trajectory of the EV can be obtained through the dynamic programming (DP algorithm. Simulation and experimental results show that the minimum energy consumption and global energy optimization can be achieved when the EV operates in the economic operation area.

  13. Development and optimization of neutron measurement methods by fission chamber on experimental reactors - management, treatment and reduction of uncertainties

    International Nuclear Information System (INIS)

    The main objectives of this research thesis are the management and reduction of uncertainties associated with measurements performed by means of a fission-chamber type sensor. The author first recalls the role of experimental reactors in nuclear research, presents the various sensors used in nuclear detection (photographic film, scintillation sensor, gas ionization sensor, semiconducting sensor, other types of radiation sensors), and more particularly addresses neutron detection (activation sensor, gas filling sensor). In a second part, the author gives an overview of the state of the art of neutron measurement by fission chamber in a mock-up reactor (signal formation, processing and post-processing, associated measurements and uncertainties, return on experience of measurements by fission chamber on Masurca and Minerve research reactors). In a third part, he reports the optimization of two intrinsic parameters of this sensor: the thickness of fissile material deposit, and the pressure and nature of the filler gas. The fourth part addresses the improvement of measurement electronics and of post-processing methods which are used for result analysis. The fifth part deals with the optimization of spectrum index measurements by means of a fission chamber. The impact of each parameter is quantified. Results explain some inconsistencies noticed in measurements performed on the Minerve reactor in 2004, and allow the improvement of biases with computed values

  14. STAR-H2: a battery-type lead-cooled fast reactor for hydrogen manufacture in a sustainable hierarchical hub-spoke energy infrastructure

    International Nuclear Information System (INIS)

    The Secure Transportable Autonomous Reactor for Hydrogen production STAR-H2 is designed to fit into a sustainable global, mid-21st century hierarchical hub-spoke nuclear energy supply architecture based on nuclear fuel, hydrogen, and electricity energy carriers and having favorable energy security, ecological and nonproliferation features. It will produce hydrogen, oxygen and potable water to service cities and their surrounding regions under an assumed electrical generation network based on fuel cells and microturbines and an assumed transportation sector using hydrogen fueled vehicles. STAR-H2 is a long refueling interval (Battery) turnkey heat supply reactor intended for production of hydrogen by thermochemical water cracking. The reactor is a Pb-cooled, mixed U-TRU-Nitride-fueled, fast spectrum reactor delivering 400 MWth of heat at 800degC core outlet temperature. The primary coolant circulates by natural circulation; the 400 MWth heat rating is set by dual requirements for natural circulation; the 400 MWth heat rating is set by dual requirements for natural circulation and for rail shippability of the vessel. An intermediate low pressure He loop carries the heat to a Ca-Br thermochemical water cracking cycle for the manufacture of H2 (and O2). The water cracking cycle rejects heat at 550degC and that heat is used in a supercritical CO2 Brayton cycle turbogenerator to provide hotel load electricity. A thermal desalinisation plant receives discharge heat at 125degC from the Brayton cycle and the brine provides for ultimate heat rejection from the cascaded thermodynamic cycles. The modified UT-3 cycle used in STAR-H2, called the Ca-Br cycle, operates at atmospheric pressure and 750-725degC, uses solid/gas separation steps and achieves about 44% efficiency. Unlike UT-3, it employs a single-stage HBr-dissociation step based on a plasma chemistry technique operating near ambient conditions. The STAR-H2 power plant will operate on a 20 year refueling interval

  15. DBD reactor design and optimization in continuous AP-PECVD from HMDSO/N2/N2O mixture

    Science.gov (United States)

    Hotmar, Petr; Caquineau, Hubert; Cozzolino, Raphaël; Gherardi, Nicolas

    2016-02-01

    Dielectric barrier discharge (DBD) deposition of thin films is increasingly studied as a promising alternative to other non-thermal processes such as low-pressure plasma-enhanced chemical vapor deposition (PECVD) or wet-coating. In this paper we demonstrate how optimizing gas injection in the DBD results in an improvement in the reactor performance. We propose to confine the precursor gas close to the deposition substrate by an additional gas flow. The performance of this design is studied though simulation of mass transport. To optimize the deposited thickness, gas cost and reactor clogging, we assess the influence of the confinement, total gas flow rate and DBD length. The confinement is found to reduce reactor clogging, even for long DBD, and increase the deposit thickness. This increase in thickness requires a proportionate increase in the gas flow-rate, making the gas-cost the main limitation of the proposed design. We show, however, that by fine-tuning the operating conditions a beneficial compromise can be obtained between the three optimization objectives.

  16. Risk management and maintenance optimization of nuclear reactor cooling piping system

    International Nuclear Information System (INIS)

    Seaside nuclear power plants have to face the ageing of nuclear reactor cooling piping systems. In order to minimize the duration of the production unit shutdown, maintenance operations have to be planned well in advance. In a context where owners of infrastructures tend to extend the life span of their goods while having to keep the safety level maximum, Oxand brings its expertise and know-how in management of infrastructures life cycle. A dedicated methodology relies on several modules that all participate in fixing network optimum replacement dates: expertise on ageing mechanisms (corrosion, cement degradation...) and the associated kinetics, expertise on impacts of ageing on functional integrity of piping systems, predictive simulation based on experience feedback, development of monitoring techniques focused on actual threats. More precisely, Oxand has designed a patented monitoring technique based on optic fiber sensors, which aims at controlling the deterioration level of piping systems. This preventive maintenance enables the owner to determine criteria for network replacement based on degradation impacts. This approach helps the owner justify his maintenance strategy and allows him to demonstrate the management of safety level. More generally, all monitoring techniques used by the owners are developed and coupled to predictive simulation tools, notably thanks to processes based on Bayesian approaches. Methodologies to evaluate and optimize operation budgets, depending on predictions of future functional deterioration and available maintenance solutions are also developed and applied. Finally, all information related to infrastructure ageing and available maintenance options are put together to reach the right solution for safe and performing infrastructure management. (authors)

  17. Risk management and maintenance optimization of nuclear reactor cooling piping system

    Science.gov (United States)

    Augé, L.; Capra, B.; Lasne, M.; Bernard, O.; Bénéfice, P.; Comby, R.

    2006-11-01

    Seaside nuclear power plants have to face the ageing of nuclear reactor cooling piping systems. In order to minimize the duration of the production unit shutdown, maintenance operations have to be planned well in advance. In a context where owners of infrastructures tend to extend the life span of their goods while having to keep the safety level maximum, Oxand brings its expertise and know-how in management of infrastructures life cycle. A dedicated methodology relies on several modules that all participate in fixing network optimum replacement dates: expertise on ageing mechanisms (corrosion, cement degradation...) and the associated kinetics, expertise on impacts of ageing on functional integrity of piping systems, predictive simulation based on experience feedback, development of monitoring techniques focused on actual threats. More precisely, Oxand has designed a patented monitoring technique based on optic fiber sensors, which aims at controlling the deterioration level of piping systems. This preventive maintenance enables the owner to determine criteria for network replacement based on degradation impacts. This approach helps the owner justify his maintenance strategy and allows him to demonstrate the management of safety level. More generally, all monitoring techniques used by the owners are developed and coupled to predictive simulation tools, notably thanks to processes based on Bayesian approaches. Methodologies to evaluate and optimize operation budgets, depending on predictions of future functional deterioration and available maintenance solutions are also developed and applied. Finally, all information related to infrastructure ageing and available maintenance options are put together to reach the right solution for safe and performing infrastructure management.

  18. FARM: a new tool for optimizing the core performance and safety characteristics of gas cooled fast reactor cores

    International Nuclear Information System (INIS)

    Designing and optimising a reactor core is rather complex as it involves neutronics, thermal-hydraulics and thermomechanics. In order to tentatively overcome these difficulties, a new approach based on simplified models, is being developed aiming in optimising both core performance (core volume, in-cycle Pu inventory..) and core safety characteristics (neutronics coefficients, core pressure drop, transient response..) of a Fast Neutron Reactor. This new approach, called FARM (Fast Reactor Methodology) is currently used for studying a Helium-Cooled Fast Reactor core with carbide fuel pins, and a SiC-based CMC (Ceramic Matrix Composite) cladding. This method has demonstrated that, for a given initial set of specifications (thermal power, inlet coolant temperature, He pressure), 10 optimization variables are sufficient to estimate fair core design features. All simplified models are built from reference CEA codes (ERANOS for neutronics, METEOR for fuel thermomechanics) by way of polynomial interpolations derived from physical analytical considerations. Some safety aspects are also considered in the analysis using analytical descriptions (decay heat removal by natural convection, thermal inertia of the core, etc...). With a multi-criterion genetic algorithm, the 10 optimization variables are then searched for improving both neutronics and safety characteristics. This new methodology allows less accurate, but optimized, core design features to be obtained and proves they are the best that fulfil all the requirements. The first series of studies justify several safety trends already considered in the conventional method (minimisation of pressure drop). Current results confirm that such an approach is possible, and leads to new core designs, similar to the reference core, but with better performance (at least, supply pumping power reduced by 30%, for the same core performance). (authors)

  19. Button batteries

    Science.gov (United States)

    Swallowing batteries ... These devices use button batteries: Calculators Cameras Hearing aids Penlights Watches ... If a person puts the battery up their nose and breathes it further in, ... problems Cough Pneumonia (if the battery goes unnoticed) ...

  20. A new evolutionary algorithm with LVQ learning for the optimization of combinatory problems as a reload of nuclear reactors

    International Nuclear Information System (INIS)

    Genetic algorithms are biologically motivated adaptive systems which have been used, with good results, for function optimization. In this work, a new learning mode, to be used by the Population-Based Incremental Learning (PBIL) algorithm, who combines mechanisms of standard genetic algorithm with simple competitive learning, has the aim to build a new evolutionary algorithm to be used in optimization of numerical problems and combinatorial problems. This new learning mode uses a variable learning rate during the optimization process, constituting a process know as proportional reward. The development of this new algorithm aims its application in the optimization of reload problem of PWR nuclear reactors. This problem can be interpreted as search of a load pattern to be used in the nucleus of the reactor in order to increase the useful life of the nuclear fuel. For the test, two classes of problems are used: numerical problems and combinatorial problem, the major interest relies on the last class. The results achieved with the tests indicate the applicability of the new learning mode, showing its potential as a developing tool in the solution of reload problem. (author)

  1. Optimal DO Setpoint Decision and Electric Cost Saving in Aerobic Reactor Using Respirometer and Air Blower Control

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang Su; Yoo, Changkyoo [Kyung Hee University, Yongin (Korea, Republic of); Kim, Minhan [Pangaea21 Ltd., Seongnam (Korea, Republic of); Kim, Jongrack [UnUsoft Ltd., Seoul (Korea, Republic of)

    2014-10-15

    Main objects for wastewater treatment operation are to maintain effluent water quality and minimize operation cost. However, the optimal operation is difficult because of the change of influent flow rate and concentrations, the nonlinear dynamics of microbiology growth rate and other environmental factors. Therefore, many wastewater treatment plants are operated for much more redundant oxygen or chemical dosing than the necessary. In this study, the optimal control scheme for dissolved oxygen (DO) is suggested to prevent over-aeration and the reduction of the electric cost in plant operation while maintaining the dissolved oxygen (DO) concentration for the metabolism of microorganisms in oxic reactor. The oxygen uptake rate (OUR) is real-time measured for the identification of influent characterization and the identification of microorganisms' oxygen requirement in oxic reactor. Optimal DO set-point needed for the micro-organism is suggested based on real-time measurement of oxygen uptake of micro-organism and the control of air blower. Therefore, both stable effluent quality and minimization of electric cost are satisfied with a suggested optimal set-point decision system by providing the necessary oxygen supply requirement to the micro-organisms coping with the variations of influent loading.

  2. ADORE-GA: Genetic algorithm variant of the ADORE algorithm for ROP detector layout optimization in CANDU reactors

    International Nuclear Information System (INIS)

    Highlights: ► ADORE is an algorithm for CANDU ROP Detector Layout Optimization. ► ADORE-GA is a Genetic Algorithm variant of the ADORE algorithm. ► Robustness test of ADORE-GA algorithm is presented in this paper. - Abstract: The regional overpower protection (ROP) systems protect CANDU® reactors against overpower in the fuel that could reduce the safety margin-to-dryout. The overpower could originate from a localized power peaking within the core or a general increase in the global core power level. The design of the detector layout for ROP systems is a challenging discrete optimization problem. In recent years, two algorithms have been developed to find a quasi optimal solution to this detector layout optimization problem. Both of these algorithms utilize the simulated annealing (SA) algorithm as their optimization engine. In the present paper, an alternative optimization algorithm, namely the genetic algorithm (GA), has been implemented as the optimization engine. The implementation is done within the ADORE algorithm. Results from evaluating the effects of using various mutation rates and crossover parameters are presented in this paper. It has been demonstrated that the algorithm is sufficiently robust in producing similar quality solutions.

  3. Design measures in evolutionary water cooled reactors to optimize for economic viability

    International Nuclear Information System (INIS)

    Since the mid 1980s, there have been various efforts to develop evolutionary water cooled reactors based on the current operating plant experience. To sustain and improve the economic viability, particular attention has been paid to the following aspects in developing evolutionary water cooled reactors: design simplification and increased operating margins, standardization in design as well as construction and operation, integration of operating plant insights, and consideration of safety, operability and constructability during the design stage. This paper reviews each item and discusses several examples from some of the evolutionary water cooled reactors being developed. (author)

  4. Optimal conditions and operational parameters for conversion of Robusta coffee residues in a continuous stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Msambichaka, B.L.; Kivaisi, A.K.; Rubindamayugi, M.S.T. [Univ. of Dar es Salaam, Applied Microbiology Unit (Tanzania, United Republic of)

    1997-12-31

    This experiment studied the possibility of optimizing anaerobic degradation, developing microbial adaptation and establishing long term process stability in a Continuous Stirred Tank Reactor (CSTR) running on Robusta coffee hulls as feed substrate. Decrease in lag phase and increase in methane production rate in batch culture experiment conducted before and after process stabilization of each operational phase in the CSTR clearly suggested that microbial adaptation to increasing coffee percentage composition was attained. Through gradual increase of coffee percentage composition, from 10% coffee, 2% VS, 20 days HRT and a 1 g VS/1/day loading rate to 80% coffee, 4.5% VS, 12 days HRT and a loading rate of 3 g VS/1/day the CSTR system was optimized at a maximum methane yield of 535 ml/g VS. Again it was possible to attain long term process stability at the above mentioned optimal operational parameters for a further 3 month period. (au)

  5. Novel photocatalytic reactor for degradation of DDT in water and its optimization model

    Institute of Scientific and Technical Information of China (English)

    Wei-hai PANG; Nai-yun GAO; Yang DENG; Yu-lin TANG

    2009-01-01

    A novel photocatalytic reactor was developed to remove(1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane)(DDT)from water.In the reactor,a cenosphere was used to support TiO2,film made by means of slo-gel.Because the cenospheres were coated with TiO2,their specific gravity was slightly increased from the original O.6-0.8 to 0.8-0.9,so that they were able to be suspended in water.With the mixed operation of a bubbler,the water in the reactor was in a well-fluidized state.The bottom of the reactor is a sand filter bed.which can be used to prevent the photocatalyst from being lost.A mathematical model of the reactor has been developed in the two primary influential factors:ultraviolet(UV)light intensity and photocatalyst concentration.Wich such a model.the reactor can be designed more reasonably.

  6. Assessment of massive integration of photovoltaic system considering rechargeable battery in Japan with high time-resolution optimal power generation mix model

    International Nuclear Information System (INIS)

    Maximizing renewables in the country's power system has been a key political agenda in Japan after the Fukushima nuclear disaster. This paper investigates the potential of PV resource, which could be systematically integrated into the Japanese power system, using a high time-resolution optimal power generation mix model. The model allows us to explicitly consider actual PV and wind output variability in 10-min time resolution for 365 days. Simulation results show that, as PV expands, the growth of PV integration into the grid slows down when the installed PV capacity is more than the scale of the peak demand, although Japan has immense potential of installable PV capacity – equivalent to 40 times of the peak. Secondly, the results imply that a large-scale PV integration potentially decreases the usage ratio of LNG combined cycle (LNGCC) in specific seasons, which is a challenge for utility companies to ensure that LNGCC is used as a profitable compensating generator for PV variability. Finally, a sensitivity analysis on rechargeable battery cost suggests that the reason for suppressing the PV output instead of storing its surplus output by the battery can be attributed to the high battery cost; hence, the improvement of its economic performance is significant to integrate the massive PV energy. - Highlights: • The authors develop a high time-resolution optimal power generation mix model. • The model can consider renewable variability in 10-min resolution for 365 days. • As PV expands, the growth of PV integration into the grid shows a slowdown. • PV integration decreases the usage ratio of the LNG combined cycle in specific seasons. • The reason for suppressing PV output is the high battery cost

  7. Optimization of a Potential New Core of the TRIGA Mark II Reactor Vienna

    International Nuclear Information System (INIS)

    The TRIGA Mark II Vienna is one of the last TRIGA reactors utilizing a mixed core with High Enrich Uranium (HEU) fuel. Due to the US Fuel Return Program, the Vienna University of Technology/Atominstitut (ATI) is obliged to return its HEU fuel by 2019. There is no final decision on any further utilization of the Vienna research reactor beyond that point. However, of all possible scenarios of the future, the conversion of the current core into Low Enriched Uranium (LEU) fuel and the complete replacement of all existing 83 burned FE(s) by new fresh FE(s) are investigated herein. This paper presents detailed reactor design calculations for three different reactor cores. The core 1 employs 104-type, core 2 uses 108-type and core 3 is loaded with mixed TRIGA fuels (i.e. 104 and 108). The combination of the Monte Carlo based neutronics code MCNP5, Oak Ridge Isotope Generation and depletion code ORIGEN2 and diffusion theory based reactor physics program TRIGLAV is used for this study. On the basis of this neutronics study, the amount of fuel required for a possible future reactor operation and its cost minimization is presented in this paper. The criticality, core excess reactivity, length of initial life cycle and thermal flux density distribution is simulated for three different cores. Keeping the utilization of existing fourteen 104-type FE(s) (i.e. six burned and eight fresh FE(s)) in view, the core 3 is found the most economical, enduring and safe option for future of the TRIGA Mark II reactor in Vienna. (author)

  8. Simulation, Control and Optimization of Single Cell Protein Production in a U-Loop Reactor

    DEFF Research Database (Denmark)

    Engoulevent, Franck Guillaume; Jørgensen, John Bagterp

    2012-01-01

    potential for alternative sources of protein production. Single cell protein (SCP) is protein produced by growth of micro organisms. Among these micro organisms, Methylococcus Capsulatus is particular interesting as it can grow on either methane or methanol and contains 70% protein. The U-Loop reactor...... is particular useful for production of SCP by M. Capsulatus as it has good gas-liquid mass transfer capabilities and also the capability to remove the signicant amount of heat developed by the reaction. In this paper we describe an implementation of a model to simulate SCP production in the U-Loop reactor. We...... report simulation results. In addition we design and compare dierent regulatory control systems for regulation of SCP production in the U-Loop reactor. The purpose of the regulatory control systems is to keep the process at a steady state and to reject disturbances. We design and implement such control...

  9. Optimization of operation schemes in boiling water reactors using neural networks; Optimizacion de esquemas de operacion en reactores de agua en ebullicion usando redes neuronales

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz S, J. J.; Castillo M, A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Pelta, D. A., E-mail: juanjose.ortiz@inin.gob.mx [Universidad de Granada, Escuela Superior de Ingenierias, Informatica y Telecomunicacion, C/Daniel Saucedo Aranda s/n, 18071 Granada (Spain)

    2012-10-15

    In previous works were presented the results of a recurrent neural network to find the best combination of several groups of fuel cells, fuel load and control bars patterns. These solution groups to each problem of Fuel Management were previously optimized by diverse optimization techniques. The neural network chooses the partial solutions so the combination of them, correspond to a good configuration of the reactor according to a function objective. The values of the involved variables in this objective function are obtained through the simulation of the combination of partial solutions by means of Simulate-3. In the present work, a multilayer neural network that learned how to predict some results of Simulate-3 was used so was possible to substitute it in the objective function for the neural network and to accelerate the response time of the whole system of this way. The preliminary results shown in this work are encouraging to continue carrying out efforts in this sense and to improve the response quality of the system. (Author)

  10. Engineering and Physics Optimization of Breed and Burn Fast Reactor Systems: Annual and Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Kevan D. Weaver; Theron Marshall; James Parry

    2005-10-01

    The Idaho National Laboratory (INL) contribution to the Nuclear Energy Research Initiative (NERI) project number 2002-005 was divided into reactor physics, and thermal-hydraulics and plant design. The research targeted credible physics and thermal-hydraulics models for a gas-cooled fast reactor, analyzing various fuel and in-core fuel cycle options to achieve a true breed and burn core, and performing a design basis Loss of Coolant Accident (LOCA) analysis on that design. For the physics analysis, a 1/8 core model was created using different enrichments and simulated equilibrium fuel loadings. The model was used to locate the hot spot of the reactor, and the peak to average energy deposition at that location. The model was also used to create contour plots of the flux and energy deposition over the volume of the reactor. The eigenvalue over time was evaluated using three different fuel configurations with the same core geometry. The breeding capabilities of this configuration were excellent for a 7% U-235 model and good in both a plutonium model and a 14% U-235 model. Changing the fuel composition from the Pu fuel which provided about 78% U-238 for breeding to the 14% U-235 fuel with about 86% U-238 slowed the rate of decrease in the eigenvalue a noticeable amount. Switching to the 7% U-235 fuel with about 93% U-238 showed an increase in the eigenvalue over time. For the thermal-hydraulic analysis, the reactor design used was the one forwarded by the MIT team. This reactor design uses helium coolant, a Brayton cycle, and has a thermal power of 600 MW. The core design parameters were supplied by MIT; however, the other key reactor components that were necessary for a plausible simulation of a LOCA were not defined. The thermal-hydraulic and plant design research concentrated on determining reasonable values for those undefined components. The LOCA simulation was intended to provide insights on the influence of the Reactor Cavity Cooling System (RCCS), the

  11. Azcaxalli: A system based on Ant Colony Optimization algorithms, applied to fuel reloads design in a Boiling Water Reactor

    International Nuclear Information System (INIS)

    This paper presents some results of the implementation of several optimization algorithms based on ant colonies, applied to the fuel reload design in a Boiling Water Reactor. The system called Azcaxalli is constructed with the following algorithms: Ant Colony System, Ant System, Best-Worst Ant System and MAX-MIN Ant System. Azcaxalli starts with a random fuel reload. Ants move into reactor core channels according to the State Transition Rule in order to select two fuel assemblies into a 1/8 part of the reactor core and change positions between them. This rule takes into account pheromone trails and acquired knowledge. Acquired knowledge is obtained from load cycle values of fuel assemblies. Azcaxalli claim is to work in order to maximize the cycle length taking into account several safety parameters. Azcaxalli's objective function involves thermal limits at the end of the cycle, cold shutdown margin at the beginning of the cycle and the neutron effective multiplication factor for a given cycle exposure. Those parameters are calculated by CM-PRESTO code. Through the Haling Principle is possible to calculate the end of the cycle. This system was applied to an equilibrium cycle of 18 months of Laguna Verde Nuclear Power Plant in Mexico. The results show that the system obtains fuel reloads with higher cycle lengths than the original fuel reload. Azcaxalli results are compared with genetic algorithms, tabu search and neural networks results.

  12. Azcaxalli: A system based on Ant Colony Optimization algorithms, applied to fuel reloads design in a Boiling Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel-Estrada, Jaime, E-mail: jaime.esquivel@fi.uaemex.m [Facultad de Ingenieria, Universidad Autonoma del Estado de Mexico, Cerro de Coatepec S/N, Toluca de Lerdo, Estado de Mexico 50000 (Mexico); Instituto Nacional de Investigaciones Nucleares, Carr. Mexico Toluca S/N, Ocoyoacac, Estado de Mexico 52750 (Mexico); Ortiz-Servin, Juan Jose, E-mail: juanjose.ortiz@inin.gob.m [Instituto Nacional de Investigaciones Nucleares, Carr. Mexico Toluca S/N, Ocoyoacac, Estado de Mexico 52750 (Mexico); Castillo, Jose Alejandro; Perusquia, Raul [Instituto Nacional de Investigaciones Nucleares, Carr. Mexico Toluca S/N, Ocoyoacac, Estado de Mexico 52750 (Mexico)

    2011-01-15

    This paper presents some results of the implementation of several optimization algorithms based on ant colonies, applied to the fuel reload design in a Boiling Water Reactor. The system called Azcaxalli is constructed with the following algorithms: Ant Colony System, Ant System, Best-Worst Ant System and MAX-MIN Ant System. Azcaxalli starts with a random fuel reload. Ants move into reactor core channels according to the State Transition Rule in order to select two fuel assemblies into a 1/8 part of the reactor core and change positions between them. This rule takes into account pheromone trails and acquired knowledge. Acquired knowledge is obtained from load cycle values of fuel assemblies. Azcaxalli claim is to work in order to maximize the cycle length taking into account several safety parameters. Azcaxalli's objective function involves thermal limits at the end of the cycle, cold shutdown margin at the beginning of the cycle and the neutron effective multiplication factor for a given cycle exposure. Those parameters are calculated by CM-PRESTO code. Through the Haling Principle is possible to calculate the end of the cycle. This system was applied to an equilibrium cycle of 18 months of Laguna Verde Nuclear Power Plant in Mexico. The results show that the system obtains fuel reloads with higher cycle lengths than the original fuel reload. Azcaxalli results are compared with genetic algorithms, tabu search and neural networks results.

  13. Analysis and optimization of the battery energy storage systems for frequency control in autonomous microgrids, by means of hardware-in-the-loop simulations

    DEFF Research Database (Denmark)

    Serban, I.; Teodorescu, Remus; Marinescu, C.

    2012-01-01

    This paper presents an original hardware-in-the-loop (HIL) solution for real-time testing and optimization of the frequency control mechanism in autonomous microgrids (MG), when battery energy storage systems (BESS) are integrated along classical and RES-based generators to stabilize the frequency...... in terms of active power, and therefore the need of improving the MG power reserve by adding energy storage systems is often demanded. The proposed HIL solution aims to improve the design of the BESS frequency control systems according to the MG characteristics, being based on aggregated models...

  14. Optimized Scheme of Connected Common Battery Pack for Subway%地铁并机共用电池组优化方案

    Institute of Scientific and Technical Information of China (English)

    郑强

    2012-01-01

    UPS电源系统是保障地铁交通正常运营的基础设施之一.本文介绍了台达UPS“1+1”并机共用电池组优化方案以及应用案例.%UPS power supply system is one of the fundamental to ensure the stable functioning of subway. This paper introduces Delta optimized scheme, UPS "1+1" connected common battery pack, and cases for its application.

  15. Flow field design and optimization based on the mass transport polarization regulation in a flow-through type vanadium flow battery

    Science.gov (United States)

    Zheng, Qiong; Xing, Feng; Li, Xianfeng; Ning, Guiling; Zhang, Huamin

    2016-08-01

    Vanadium flow battery holds great promise for use in large scale energy storage applications. However, the power density is relatively low, leading to significant increase in the system cost. Apart from the kinetic and electronic conductivity improvement, the mass transport enhancement is also necessary to further increase the power density and reduce the system cost. To better understand the mass transport limitations, in the research, the space-varying and time-varying characteristic of the mass transport polarization is investigated based on the analysis of the flow velocity and reactant concentration in the bulk electrolyte by modeling. The result demonstrates that the varying characteristic of mass transport polarization is more obvious at high SoC or high current densities. To soften the adverse impact of the mass transport polarization, a new rectangular plug flow battery with a plug flow and short flow path is designed and optimized based on the mass transport polarization regulation (reducing the mass transport polarization and improving its uniformity of distribution). The regulation strategy of mass transport polarization is practical for the performance improvement in VFBs, especially for high power density VFBs. The findings in the research are also applicable for other flow batteries and instructive for practical use.

  16. Optimization of Overall Project of ChinaLEad-Alloy Cooled Reactor

    Institute of Scientific and Technical Information of China (English)

    DUAN; Tian-ying; LONG; Bin; HU; Yun; LIU; Xing-ming; SUN; Gang; LIU; Yi-zhe; YANG; Yong; PEI; Zhi-yong; FENG; Wei-wei; YU; Xiao

    2012-01-01

    <正>The application of accelerator driven sub-critical reactor which is able to transmute spent fuel and long-lived radioactive fission products is highly concerned in the international research projects. Lots of researches have been done in many countries. While China Institute of Atomic Energy has built a fast

  17. Optimization of U–Th fuel in heavy water moderated thermal breeder reactors using multivariate regression analysis and genetic algorithms

    International Nuclear Information System (INIS)

    Highlights: • A new method useful for the parametric analysis and optimization of reactor core designs. • This uses the strengths of genetic algorithms (GA), and regression splines. • The method is applied to the core fuel pin cell of a PHWR design. • Tools like java, R, and codes like Serpent, Matlab are used in this research. - Abstract: An analysis and optimization of a set of neutronics parameters of a thorium-fueled pressurized heavy water reactor core fuel has been performed. The analysis covers a detailed pin-cell analysis of a seed-blanket configuration, where the seed is composed of natural uranium, and the blanket is composed of thorium. Genetic algorithms (GA) is used to optimize the input parameters to meet a specific set of objectives related to: infinite multiplication factor, initial breeding ratio, and specific nuclide’s effective microscopic cross-section. The core input parameters are the pitch-to-diameter ratio, and blanket material composition. Recursive partitioning of decision trees (rpart) multivariate regression model is used to perform a predictive analysis of the samples generated from the GA module. Reactor designs are usually complex and a simulation needs a significantly large amount time to execute, hence implementation of GA or any other global optimization techniques is not feasible, therefore we present a new method of using rpart in conjunction with GA. Due to using rpart, we do not necessarily need to run the neutronics simulation for all the inputs generated from the GA module rather, run the simulations for a predefined set of inputs, build a regression fit to the input and the output parameters, and then use this fit to predict the output parameters for the inputs generated by GA. The rpart model is implemented as a library using R programming language. The results suggest that the initial breeding ratio tends to increase due to a harder neutron spectrum, however a softer neutron spectrum is desired to limit the

  18. Optimization of chemical reactor feed by simulations based on a kinetic approach.

    Science.gov (United States)

    Guinand, Charles; Dabros, Michal; Roduit, Bertrand; Meyer, Thierry; Stoessel, Francis

    2014-10-01

    Chemical incidents are typically caused by loss of control, resulting in runaway reactions or process deviations in different stages of the production. In the case of fed-batch reactors, the problem generally encountered is the accumulation of heat. This is directly related to the temperature of the process, the reaction kinetics and adiabatic temperature rise, which is the maximum temperature attainable in the event of cooling failure. The main possibility to control the heat accumulation is the use of a well-controlled adapted feed. The feed rate can be adjusted by using reaction and reactor dynamic models coupled to Model Predictive Control. Thereby, it is possible to predict the best feed profile respecting the safety constraints.

  19. A Virtual Reality Framework to Optimize Design, Operation and Refueling of GEN-IV Reactors.

    Energy Technology Data Exchange (ETDEWEB)

    Rizwan-uddin; Nick Karancevic; Stefano Markidis; Joel Dixon; Cheng Luo; Jared Reynolds

    2008-04-23

    many GEN-IV candidate designs are currently under investigation. Technical issues related to material, safety and economics are being addressed at research laboratories, industry and in academia. After safety, economic feasibility is likely to be the most important crterion in the success of GEN-IV design(s). Lessons learned from the designers and operators of GEN-II (and GEN-III) reactors must play a vital role in achieving both safety and economic feasibility goals.

  20. A Virtual Reality Framework to Optimize Design, Operation and Refueling of GEN-IV Reactors

    International Nuclear Information System (INIS)

    Many GEN-IV candidate designs are currently under investigation. Technical issues related to material, safety and economics are being addressed at research laboratories, industry and in academia. After safety, economic feasibility is likely to be the most important criterion in the success of GEN-IV design(s). Lessons learned from the designers and operators of GEN-II (and GEN-III) reactors must play a vital role in achieving both safety and economic feasibility goals

  1. EFFECTS OF 4-CHLOROPHENOL LOADINGS ON ACCLIMATION OF BIOMASS WITH OPTIMIZED FIXED TIME SEQUENCING BATCH REACTOR

    Directory of Open Access Journals (Sweden)

    H. Movahedyan, A. Assadi, M. M. Amin

    2008-10-01

    Full Text Available Abstract: Chlorinated phenols in many industrial effluents are usually difficult to be removed by conventional biological treatment processes. Performance of the aerobic sequencing batch reactor treating 4-chlorophenol containing wastewater at different loadings rates from 0.0075 to 1.2 g4CP/L.d was evaluated. The sequencing batch reactor was operated with fill, react, settle and decant phases in the order of 10:370:90:10 min, respectively, for a cycle time of 8 h at 10 days solid retention time and 16 h hydraulic retention time in the stable period. The effects of 4-chlorophenol loadings on the 4-chlorophenol and chemical oxygen demand removal percents, yield coefficient (Y, biomass variation and sludge volume index were investigated. High chemical oxygen demand removal efficiencies (95±3.5% and approximately complete 4-chlorophenol removal (>99% were observed even in the absence of growth substrate. The degradation of 4-chlorophenol led to formation of 5-chloro-2-hydroxymuconic semialdehyde, which was more oxidized, indicating complete disappearance of 4-chlorophenol via meta-cleavage pathway. A compact sludge with excellent settleability (sludge volume index=47±6.1 mL/g developed during entire acclimation period. High removal efficiencies with sequencing batch reactor may be due to enforced short term unsteady state conditions coupled with periodic exposure of the microorganisms to defined process conditions which facilitate the required metabolic pathways for treating xenobiotics containing wastewater.

  2. Long-term assessment of economic plug-in hybrid electric vehicle battery lifetime degradation management through near optimal fuel cell load sharing

    Science.gov (United States)

    Martel, François; Dubé, Yves; Kelouwani, Sousso; Jaguemont, Joris; Agbossou, Kodjo

    2016-06-01

    This work evaluates the performance of a plug-in hybrid electric vehicle (PHEV) energy management process that relies on the active management of the degradation of its energy carriers - in this scenario, a lithium-ion battery pack and a polymer electrolyte membrane fuel cell (PEMFC) - to produce a near economically-optimal vehicle operating profile over its entire useful lifetime. This solution is obtained through experimentally-supported PHEV models exploited by an optimal discrete dynamic programming (DDP) algorithm designed to efficiently process vehicle usage cycles over an extended timescale. Our results demonstrate the economic and component lifetime gains afforded by our strategy when compared with alternative rule-based PHEV energy management benchmarks.

  3. A Novel Numerical Algorithm for Optimal Sizing of a Photovoltaic/Wind/Diesel Generator/Battery Microgrid Using Loss of Load Probability Index

    Directory of Open Access Journals (Sweden)

    Hussein A. Kazem

    2013-01-01

    Full Text Available This paper presents a method for determining optimal sizes of PV array, wind turbine, diesel generator, and storage battery installed in a building integrated system. The objective of the proposed optimization is to design the system that can supply a building load demand at minimum cost and maximum availability. The mathematical models for the system components as well as meteorological variables such as solar energy, temperature, and wind speed are employed for this purpose. Moreover, the results showed that the optimum sizing ratios (the daily energy generated by the source to the daily energy demand for the PV array, wind turbine, diesel generator, and battery for a system located in Sohar, Oman, are 0.737, 0.46, 0.22, and 0.17, respectively. A case study represented by a system consisting of 30 kWp PV array (36%, 18 kWp wind farm (55%, and 5 kVA diesel generator (9% is presented. This system is supposed to power a 200 kWh/day load demand. It is found that the generated energy share of the PV array, wind farm, and diesel generator is 36%, 55%, and 9%, respectively, while the cost of energy is 0.17 USD/kWh.

  4. Optimal Conditions for Preparing Ultra-Fine CeO2 Powders in A Submerged Circulative Impinging Stream Reactor

    Institute of Scientific and Technical Information of China (English)

    Chi Ru'an; Xu Zhigao; Wu Yuanxin; Wang Cunwen

    2007-01-01

    Cerium carbonate powders were produced in a submerged circulation impinging stream reactor (SCISR) from Ce(NO3)3·6H2O. NH4HCO3 was used as a precipitant in the reaction. Cerium carbonate powders were roasted to produce ultra-fine cerium dioxide (CeO2) powders. The optimal conditions of such production process were obtained by orthogonal and one-factor experiments. The results showed that ultra-fine and narrowly distributed cerium carbonate powders were produced under the optimal flowing conditions. The concentrations of Ce(NO3)3 and NH4HCO3 solutions were 0.25 and 0.3 mol·L-1, respectively. The concentration of PEG4000 added in these two solutions was 4 g·L-1. The stirring ratio, reaction temperature, feeding time, solution pH, reaction time and digestion time were 900 r·min-1, 80 ℃, 20 min, 5~6, 5 min and 1 h, respectively. The final product, CeO2 powders, was obtained by roasting the produced cerium carbonate in air for 3 h at 500 ℃. The finally produced CeO2 powders were torispherical particles with a narrow size distribution of 0.8~2.5 μm. The crystal structure of CeO2 powders belonged to cubic crystal system and its space point group was O5H-FM3M. Under optimal conditions, powders produced by SCISR were finer and more narrowly distributed than that by Stirred Tank Reactor (STR).

  5. Final report-passive safety optimization in liquid sodium-cooled reactors.

    Energy Technology Data Exchange (ETDEWEB)

    Cahalana, J. E.; Hahn, D.; Nuclear Engineering Division; Korea Atomic Energy Research Inst.

    2007-08-13

    This report summarizes the results of a three-year collaboration between Argonne National Laboratory (ANL) and the Korea Atomic Energy Research Institute (KAERI) to identify and quantify the performance of innovative design features in metallic-fueled, sodium-cooled fast reactor designs. The objective of the work was to establish the reliability and safety margin enhancements provided by design innovations offering significant potential for construction, maintenance, and operating cost reductions. The project goal was accomplished with a combination of advanced model development (Task 1), analysis of innovative design and safety features (Tasks 2 and 3), and planning of key safety experiments (Task 4). Task 1--Computational Methods for Analysis of Passive Safety Design Features: An advanced three-dimensional subassembly thermal-hydraulic model was developed jointly and implemented in ANL and KAERI computer codes. The objective of the model development effort was to provide a high-accuracy capability to predict fuel, cladding, coolant, and structural temperatures in reactor fuel subassemblies, and thereby reduce the uncertainties associated with lower fidelity models previously used for safety and design analysis. The project included model formulation, implementation, and verification by application to available reactor tests performed at EBR-II. Task 2--Comparative Analysis and Evaluation of Innovative Design Features: Integrated safety assessments of innovative liquid metal reactor designs were performed to quantify the performance of inherent safety features. The objective of the analysis effort was to identify the potential safety margin enhancements possible in a sodium-cooled, metal-fueled reactor design by use of passive safety mechanisms to mitigate low-probability accident consequences. The project included baseline analyses using state-of-the-art computational models and advanced analyses using the new model developed in Task 1. Task 3--Safety

  6. Battery Pack Thermal Design

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, Ahmad

    2016-06-14

    This presentation describes the thermal design of battery packs at the National Renewable Energy Laboratory. A battery thermal management system essential for xEVs for both normal operation during daily driving (achieving life and performance) and off-normal operation during abuse conditions (achieving safety). The battery thermal management system needs to be optimized with the right tools for the lowest cost. Experimental tools such as NREL's isothermal battery calorimeter, thermal imaging, and heat transfer setups are needed. Thermal models and computer-aided engineering tools are useful for robust designs. During abuse conditions, designs should prevent cell-to-cell propagation in a module/pack (i.e., keep the fire small and manageable). NREL's battery ISC device can be used for evaluating the robustness of a module/pack to cell-to-cell propagation.

  7. Geometric optimization of spallation targets for the MYRRHA reactor using MCNPX simulations

    Energy Technology Data Exchange (ETDEWEB)

    Rebello Junior, Andre Luiz P.; Martinez, Aquilino S.; Golcalves, Alessandro C., E-mail: junior.rebello@poli.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear

    2013-07-01

    The present work aims to evaluate the behavior of neutron multiplicity in a spallation target using MCNPX simulations, focusing on its application in the MYRRHA reactor. It was studied the two types of spallation target proposed for the MYRRHA project, windowless and windows target, in order to compare them and nd saturation boundaries. Some saturation boundaries were found and the windowless target proved to be as viable as the windows one. Each one produced nearly the same number of neutrons per incident proton. Using the concept of neutron cost, it was also observed that the optimum conditions on neutron production occur at about 1GeV, for both target designs. (author)

  8. Simulation research and optimal design for digital power regulating system of China advanced research reactor

    International Nuclear Information System (INIS)

    Based on SimPort simulation platform of nuclear power plant, a simulation model for Digital Power Regulating System (DPRS) of China Advanced Research Reactor (CARR) was established. By simulating the transient state of DPRS using this model, the adjusting parameters for the digital PID controller were determined. According to the features of the driving mechanism, the effects of the driving accuracy of the control rod and the displacement delay between electromagnetic coil and armature upon system stability and the regulating performance were analyzed, furthermore, their stability limit values were obtained respectively. The research results of this paper have some engineering practical value. (authors)

  9. Optimization of process parameters in flash pyrolysis of waste tyres to liquid and gaseous fuel in a fluidized bed reactor

    International Nuclear Information System (INIS)

    Highlights: ► Non-recyclable, hazards, under-utilized waste tyre was converted to useful fuel. ► Design of experiment was used to optimize the process parameters. ► Fuel compatibility for IC engines was tested by standard fuel testing procedures. ► Optimized process parameters were tested and the empirical model validated. - Abstract: Pyrolysis process offers solution to utilize huge quantity of worn out automobile tyres to produce fuel for energy needs. Shredded tyre wastes were subjected to pyrolysis at atmospheric pressure under inert gas atmosphere in a fluidized bed combustion setup. The shredded tyre particle size, the feed rate of the feed stock, and the pyrolysis temperature were varied systematically as per the designed experiment to study their influence on product yield. Maximizing the oil yield and subduing the gas and char yield is the objective to optimize the process parameters. A low pyrolysis temperature of 440 °C with low feed rate increases the residence time in the combustion reactor yielding maximum oil. The physical properties of raw pyrolysis oil, distilled oil and the evolved gases were done to find its suitability to utilize them as alternatives to the conventional fuels

  10. Optimization of Water Chemistry to Ensure Reliable Water Reactor Fuel Performance at High Burnup and in Ageing Plant (FUWAC)

    International Nuclear Information System (INIS)

    This report presents the results of the Coordinated Research Project (CRP) on Optimization of Water Chemistry to Ensure Reliable Water Reactor Fuel Performance at High Burnup and in Ageing Plants (FUWAC, 2006-2009). It provides an overview of the results of the investigations into the current state of water chemistry practice and concerns in the primary circuit of water cooled power reactors including: corrosion of primary circuit materials; deposit composition and thickness on the fuel; crud induced power shift; fuel oxide growth and thickness; radioactivity buildup in the reactor coolant system (RCS). The FUWAC CRP is a follow-up to the DAWAC CRP (Data Processing Technologies and Diagnostics for Water Chemistry and Corrosion Control in Nuclear Power Plants 2001-2005). The DAWAC project improved the data processing technologies and diagnostics for water chemistry and corrosion control in nuclear power plants (NPPs). With the improved methods for controlling and monitoring water chemistry now available, it was felt that a review of the principles of water chemistry management should be undertaken in the light of new materials, more onerous operating conditions, emergent issues such as CIPS, also known as axial offset anomaly (AOA) and the ageing of operating power plant. In the framework of this CRP, water chemistry specialists from 16 nuclear utilities and research organizations, representing 15 countries, exchanged experimental and operational data, models and insights into water chemistry management. The CD-ROM attached to this IAEA-TECDOC includes the report itself, detailed progress reports of three Research Coordination Meetings (RCMs) (Annexes I-III) and the reports and presentations made during the project by the participants.

  11. Simulation of radiation dose distribution and thermal analysis for the bulk shielding of an optimized molten salt reactor

    Institute of Scientific and Technical Information of China (English)

    张志宏; 夏晓彬; 蔡军; 王建华; 李长园; 葛良全; 张庆贤

    2015-01-01

    The Chinese Academy of Science has launched a thorium-based molten-salt reactor (TMSR) research project with a mission to research and develop a fission energy system of the fourth generation. The TMSR project intends to construct a liquid fuel molten-salt reactor (TMSR-LF), which uses fluoride salt as both the fuel and coolant, and a solid fuel molten-salt reactor (TMSR-SF), which uses fluoride salt as coolant and TRISO fuel. An optimized 2 MWth TMSR-LF has been designed to solve major technological challenges in the Th-U fuel cycle. Preliminary conceptual shielding design has also been performed to develop bulk shielding. In this study, the radiation dose and temperature distribution of the shielding bulk due to the core were simulated and analyzed by performing Monte Carlo simulations and computational fluid dynamics (CFD) analysis. The MCNP calculated dose rate and neutron and gamma spectra indicate that the total dose rate due to the core at the external surface of the concrete wall was 1.91 µSv/h in the radial direction, 1.16 µSv/h above and 1.33 µSv/h below the bulk shielding. All the radiation dose rates due to the core were below the design criteria. Thermal analysis results show that the temperature at the outermost surface of the bulk shielding was 333.86 K, which was below the required limit value. The results indicate that the designed bulk shielding satisfies the radiation shielding requirements for the 2 MWth TMSR-LF.

  12. Optimization and implementation study of plutonium disposition using existing CANDU Reactors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    Since early 1994, the Department of Energy has been sponsoring studies aimed at evaluating the merits of disposing of surplus US weapons plutonium as Mixed Oxide (MOX) fuel in existing commercial Canadian Pressurized Heavy Water reactors, known as CANDU`s. The first report, submitted to DOE in July, 1994 (the 1994 Executive Summary is attached), identified practical and safe options for the consumption of 50 to 100 tons of plutonium in 25 years in some of the existing CANDU reactors operating the Bruce A generating station, on Lake Huron, about 300 km north east of Detroit. By designing the fuel and nuclear performance to operate within existing experience and operating/performance envelope, and by utilizing existing fuel fabrication and transportation facilities and methods, a low cost, low risk method for long term plutonium disposition was developed. In December, 1995, in response to evolving Mission Requirements, the DOE requested a further study of the CANDU option with emphasis on more rapid disposition of the plutonium, and retaining the early start and low risk features of the earlier work. This report is the result of that additional work.

  13. Do existing research reactors teach us all about beam tube optimization?

    International Nuclear Information System (INIS)

    The contribution makes the attempt to analyse the data base available in the literature and in Siemens' own projects and to find out potential systematics from the existing research reactor with beam tubes, separated into reactors with different reflectors and distinguished for tangential and radial tubes and cold neutron sources, resp. Some generic calculations serve as gauging data. The contribution is not meant as critics on any design.The results might serve supporting designers and operators when evaluating the pros and cons of existing or planned design in terms of the optimum beam tubes. Existing lacks of systematics are evaluated in view of suitable explanations and constraints, which do not allow optimisation. Examples pf such constraints are the different material layers between fuel zone and reflector zone which have various reasons. The limited data in the literature plus the numerous lacks of precision of the representation of those data should be an incentive to improve the performed analysis by collecting more exact data and re-doing the evaluation before answering the title-question really. (author)

  14. Continuous Production of Lipase-Catalyzed Biodiesel in a Packed-Bed Reactor: Optimization and Enzyme Reuse Study

    Directory of Open Access Journals (Sweden)

    Hsiao-Ching Chen

    2011-01-01

    Full Text Available An optimal continuous production of biodiesel by methanolysis of soybean oil in a packed-bed reactor was developed using immobilized lipase (Novozym 435 as a catalyst in a tert-butanol solvent system. Response surface methodology (RSM and Box-Behnken design were employed to evaluate the effects of reaction temperature, flow rate, and substrate molar ratio on the molar conversion of biodiesel. The results showed that flow rate and temperature have significant effects on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions were as follows: flow rate 0.1 mL/min, temperature 52.1∘C, and substrate molar ratio 1 : 4. The predicted and experimental values of molar conversion were 83.31±2.07% and 82.81±.98%, respectively. Furthermore, the continuous process over 30 days showed no appreciable decrease in the molar conversion. The paper demonstrates the applicability of using immobilized lipase and a packed-bed reactor for continuous biodiesel synthesis.

  15. Analysis of occupational doses from the CDTN reactor TRIGA IPR-R1 for radiation protection optimization

    International Nuclear Information System (INIS)

    Worker and area monitoring have routinely been done around the CDTN TRIGA IPR-R1 research reactor aiming to optimize and assure radiation protection safety. As part of the implementation of the ALARA program, individual doses from planned practices were analyzed. Personnel dose equivalents, Hp(10), from up to 39 occupationally exposed workers were daily reported during their stay in the restricted area. Measurements were done with a RAD-60 Rados electronic personal dosimeter with a 1 μSv low detection limit. Results of about 5000 measurements in a year obtained during 2009 and 2010 showed that monthly doses did not exceed 60 μSv, except in very specific cases of non-routine practices. Results also suggested that values of 40, 100 and 800 μSv could be adopted as weekly, monthly and annual dose constraints. Considering that measured doses were very small when compared to the 20 mSv/year dose limit, it was concluded that the adoption of the dose constraints was enough to assume the compliance with the ALARA principle and that changes in the routine procedure or in the reactor facility design are not needed. (author)

  16. Optimization of Nitrogen Removal from Synthetic Wastewater by Eliminating Nitrification Step of a Fixed-Film Bed Reactor

    Directory of Open Access Journals (Sweden)

    M Hajsardar

    2016-06-01

    Full Text Available Background and Objectives: In order to optimize wastewater nitrogen removal and to reduce the problems of entering nutrients in final receptors, for example, a lake, partial nitrification, as a novel nitrogen removal method, was studied. Materials and Methods: The efficiency of simultaneous nitrification and denitrification (SND in partial nitrification through nitrification/denitrification in fixed-film reactor was surveyed. In this process, ammonium was converted to nitrite by ammonium oxidizing bacteria (AOB but the activity of nitrite oxidizing bacteria (NOB was limited at low dissolved oxygen (DO level. The inflection points of oxidation-reduction potential (ORP profile were used as the indicators of process optimization. Results: This research showed that in period 2 at fixed DO level of 0.5 mg/L, nitrite accumulation rate (NAR was higher than period 1 in which DO was declined from 1 to 0.5 mg/L. In contrast to period 1, SND efficiency was reduced in period 2. In period 3, by increment of the carbon to nitrogen ratio (C/N to 12.5, NAR increased to 71.4 % and SND efficiency increased to 96.7%. In the long term analysis of proposed method, SND efficiency was, at least, 90%.    Conclusion: Proper C/N ratio and minimum DO level resulted in higher nitrogen removal efficiencies than the operation in which DO was decreased during aerobic phase. By using a fixed-film reactor and without considering an anoxic step, at DO level of 0.5 mg/L, maximum SND efficiency and maximum NAR would be achieved. 

  17. Contribution to the optimization of the coupling of nuclear reactors to desalination processes; Contribution a l'optimisation du couplage des reacteurs nucleaires aux procedes de dessalement

    Energy Technology Data Exchange (ETDEWEB)

    Dardour, S

    2007-04-15

    This work deals with modelling, simulation and optimization of the coupling between nuclear reactors (PWR, modular high temperature reactors) and desalination processes (multiple effect distillation, reverse osmosis). The reactors considered in this study are PWR (Pressurized Water Reactor) and GTMHR (Gas Turbine Modular Helium Reactor). The desalination processes retained are MED (Multi Effect Distillation) and SWRO (Sea Water Reverse Osmosis). A software tool: EXCELEES of thermodynamic modelling of coupled systems, based on the Engineering Algebraic Equation Solver has been developed. Models of energy conversion systems and of membrane desalination processes and distillation have been developed. Based on the first and second principles of thermodynamics, these models have allowed to determine the optimal running point of the coupled systems. The thermodynamic analysis has been completed by a first economic evaluation. Based on the use of the DEEP software of the IAEA, this evaluation has confirmed the interest to use these types of reactors for desalination. A modelling tool of thermal processes of desalination in dynamic condition has been developed too. This tool has been applied to the study of the dynamics of an existing plant and has given satisfying results. A first safety checking has been at last carried out. The transients able to jeopardize the integrated system have been identified. Several measures aiming at consolidate the safety have been proposed. (O.M.)

  18. 全钒液流电池流场模拟与优化%Simulation and optimization of flow field of all vanadium redox flow battery

    Institute of Scientific and Technical Information of China (English)

    马相坤; 张华民; 邢枫; 孙晨曦

    2012-01-01

    The structure of flow field is one of the key factors that affect the performance of all vanadium redox flow battery. A two-dimensional model for the flow field of all vanadium redox flow battery was proposed based on CFD technology. The distribution of electrolyte in electrode in the specified structure of flow field could be obtained by the proposed model. The flow field was optimized to enhance the distributional uniformity of electrolyte in electrode. The conclusion indicates that the distributional uniformity can be improved by increasing the number of distributional ports and extending the length of inlet vertical channel. Meanwhile, the effects of width of distributional channel and flow rate on distributional uniformity of electrolyte were considered. The conclusion has great guidance for the design of flow field of all vanadium redox flow battery.%流场结构是影响全钒液流电池性能的关键问题之一.基于CFD技术建立全钒液流电池流场的二维数学模型,通过模拟获得在给定流场结构下电解液在石墨毡电极内的分布规律,优化流场结构提高电解液在石墨毡电极内分布的均匀性.研究结果表明,增加分配口个数和延长入口竖直主流道的长度能够有效提高电解液的分配均匀性;同时考察了分配流道宽度和流量对电解液分配均匀性的影响;所得结论对全钒液流电池流场结构设计具有重要的指导意义.

  19. Optimization of a heterogeneous catalytic hydrodynamic cavitation reactor performance in decolorization of Rhodamine B: application of scrap iron sheets.

    Science.gov (United States)

    Basiri Parsa, Jalal; Ebrahimzadeh Zonouzian, Seyyed Alireza

    2013-11-01

    A low pressure pilot scale hydrodynamic cavitation (HC) reactor with 30 L volume, using fixed scrap iron sheets, as the heterogeneous catalyst, with no external source of H2O2 was devised to investigate the effects of operating parameters of the HC reactor performance. In situ generation of Fenton reagents suggested an induced advanced Fenton process (IAFP) to explain the enhancing effect of the used catalyst in the HC process. The reactor optimization was done based upon the extent of decolorization (ED) of aqueous solution of Rhodamine B (RhB). To have a perfect study on the pertinent parameters of the heterogeneous catalyzed HC reactor, the following cases as, the effects of scrap iron sheets, inlet pressure (2.4-5.8 bar), the distance between orifice plates and catalyst sheets (submerged and inline located orifice plates), back-pressure (2-6 bar), orifice plates type (4 various orifice plates), pH (2-10) and initial RhB concentration (2-14 mg L(-1)) have been investigated. The results showed that the highest cavitational yield can be obtained at pH 3 and initial dye concentration of 10 mg L(-1). Also, an increase in the inlet pressure would lead to an increase in the ED. In addition, it was found that using the deeper holes (thicker orifice plates) would lead to lower ED, and holes with larger diameter would lead to the higher ED in the same cross-sectional area, but in the same holes' diameters, higher cross-sectional area leads to the lower ED. The submerged operation mode showed a greater cavitational effects rather than the inline mode. Also, for the inline mode, the optimum value of 3 bar was obtained for the back-pressure condition in the system. Moreover, according to the analysis of changes in the UV-Vis spectra of RhB, both degradation of RhB chromophore structure and N-deethylation were occurred during the catalyzed HC process.

  20. 基于遗传算法的电池管理策略%Battery Management Based on Genetic Algorithm Optimization

    Institute of Scientific and Technical Information of China (English)

    赵向阳; 王杏玄; 罗文

    2015-01-01

    电池储能可提高风、光等可再生能源在微电网中的接入水平,常规研究只考虑了通过储能控制微电网与配电网交互功率的波动性。研究含新能源发电的微电网与配电网交互功率成本最低或收益最高的蓄电池充放电策略及电池容量、初始荷电状态与优化效果的问题,建立了在最大功率跟踪风机出力情况下的交换功率最经济模型。在求解算法方面,采用以自然选择和遗传理论为基础的高效全局寻优搜索的遗传算法,以电池充放电功率、荷电状态和系统功率平衡为约束。最后针对风电和负荷波动的影响,经算例证明,以交互功率费用为目标经遗传算法优化电池调度后,可在不影响其波动性的基础上很大程度地提高交互功率的经济性,为今后制定储能电池更加完善的充放电管理策略提供一定的借鉴意义。%Energy storage system can improve the capacity of renewable energy resources in the micro-grid like so-lar energy, wind energy and so forth. Conventional researches consider only the standard deviation of the interactive power between micro-grid and distribution network. Analyzing the charging and discharging strategy of the battery to get the lowest cost and the highest profit from the micro-grid, it is important to consider the battery capacity, the in-itial state of charge and the optimization effect, then the most economic model of the interaction power is established in the maximum power tracking of the output of the wind turbine. Genetic algorithm, an efficient global optimization search algorithm, based on natural selection and genetic theory, has the advantages of fast convergence, simple calculation, versatility and so on. Finally, an algorithm example on the battery state and power balance constraints optimizes battery scheduling to minimize the interactive power cost by the genetic algorithm. Thus the interactive power economy can be

  1. Battery Management Based on Genetic Algorithm Optimization%基于遗传算法的电池管理策略

    Institute of Scientific and Technical Information of China (English)

    赵向阳; 王杏玄; 罗文

    2015-01-01

    Energy storage system can improve the capacity of renewable energy resources in the micro-grid like so-lar energy, wind energy and so forth. Conventional researches consider only the standard deviation of the interactive power between micro-grid and distribution network. Analyzing the charging and discharging strategy of the battery to get the lowest cost and the highest profit from the micro-grid, it is important to consider the battery capacity, the in-itial state of charge and the optimization effect, then the most economic model of the interaction power is established in the maximum power tracking of the output of the wind turbine. Genetic algorithm, an efficient global optimization search algorithm, based on natural selection and genetic theory, has the advantages of fast convergence, simple calculation, versatility and so on. Finally, an algorithm example on the battery state and power balance constraints optimizes battery scheduling to minimize the interactive power cost by the genetic algorithm. Thus the interactive power economy can be improved greatly on the basis of keeping the interaction power volatility at a certain value. The result shows that this research can play a guiding role in making a more comprehensive storage battery strategy of charging and discharging in the future.%电池储能可提高风、光等可再生能源在微电网中的接入水平,常规研究只考虑了通过储能控制微电网与配电网交互功率的波动性。研究含新能源发电的微电网与配电网交互功率成本最低或收益最高的蓄电池充放电策略及电池容量、初始荷电状态与优化效果的问题,建立了在最大功率跟踪风机出力情况下的交换功率最经济模型。在求解算法方面,采用以自然选择和遗传理论为基础的高效全局寻优搜索的遗传算法,以电池充放电功率、荷电状态和系统功率平衡为约束。最后针对风电和负荷波动的影响,经算例证明,

  2. Yield optimization in a cycled trickle-bed reactor: ethanol catalytic oxidation as a case study

    Energy Technology Data Exchange (ETDEWEB)

    Ayude, A.; Haure, P. [INTEMA, CONICET, Mar del Plata (Argentina); Cassanello, M. [Universidad de Buenos Aires, PINMATE, Departamento de Industrias, FCEyN, Buenos Aires (Argentina); Martinez, O. [Departamento de Ingenieria Quimica, FI-UNLP-CINDECA, La Plata (Argentina)

    2012-05-15

    The effect of slow ON-OFF liquid flow modulation on the yield of consecutive reactions is investigated for oxidation of aqueous ethanol solutions using a 0.5 % Pd/Al{sub 2}O{sub 3} commercial catalyst in a laboratory trickle-bed reactor. Experiments with modulated liquid flow rate (MLFR) were performed under the same hydrodynamic conditions (degree of wetting, liquid holdup) as experiments with constant liquid flow rate (CLFR). Thus, the impact of the duration of wet and dry cycles as well as the period can be independently investigated. Depending on cycling conditions, acetaldehyde or acetic acid production is favored with MLFR compared to CLFR. Results suggest both the opportunity and challenge of finding a way to tune the cycling parameters for producing the most appropriate product. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Simulation research and optimal design for digital power regulating system of China advanced research reactor

    International Nuclear Information System (INIS)

    Based on SimPort simulation platform of nuclear power plant, a simulation model for Digital Power Regulating System (DPRS) of China Advanced Research Reactor (CARR) was established. The transient state of DPRS was simulation studied using this model. According to the characteristics of the driving mechanism of the control rods, the effects of the driving precision of the control rod and its displacement delay upon the system stability were analyzed. Considering the process requirements of CARR and the function characteristic of DRPS, the adjusting parameters for the digital PID controller and the stability limits of the driving mechanism of the control rods were obtained. The sampling period of the digital PID controller is 100 ms and its proportion gain is 300. The stability limit of the driving precision of the control rod is 0.4 mm. The stability limit of displacement delay between electromagnetic coil and armature is 6.0 mm. (authors)

  4. On the optimal control of fed-batch reactors with substrate-inhibited kinetics.

    Science.gov (United States)

    Cazzador, L

    1988-05-01

    The optimal feed rate profiles, for fed-batch fermentation that maximizes the biomass production and accounts for time, are analyzed. The solution can be found only if the final arc of the optimal control is a batch arc, since in this case the final concentrations of substrate and biomass can be determined by ulterior conditions on the mass balance and on the final growth rate of biomass and thus it is possible to solve the resulting time optimal problem by using Green's theorem. This evidences the "turnpike property" of the solution, which tries to spend the maximum time on or at least near the singular arc along which the substrate concentration is maintained constant. The optimality of the final batch arc is related to the time operational cost in the performance index. The sequence of the control depends on the initial conditions for which six different regions, with the respective patterns, have been identified, in case the performance index allows the control sequence to have a final batch.

  5. Immobilized enzyme reactor chromatography: Optimization of protein retention and enzyme activity in monolithic silica stationary phases

    Energy Technology Data Exchange (ETDEWEB)

    Besanger, Travis R. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Hodgson, Richard J. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Green, James R.A. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Brennan, John D. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada)]. E-mail: brennanj@mcmaster.ca

    2006-03-30

    Our group recently reported on the application of protein-doped monolithic silica columns for immobilized enzyme reactor chromatography, which allowed screening of enzyme inhibitors present in mixtures using mass spectrometry for detection. The enzyme was immobilized by entrapment within a bimodal meso/macroporous silica material prepared by a biocompatible sol-gel processing route. While such columns proved to be useful for applications such as screening of protein-ligand interactions, significant amounts of entrapped proteins leached from the columns owing to the high proportion of macropores within the materials. Herein, we describe a detailed study of factors affecting the morphology of protein-doped bioaffinity columns and demonstrate that specific pH values and concentrations of poly(ethylene glycol) can be used to prepare essentially mesoporous columns that retain over 80% of initially loaded enzyme in an active and accessible form and yet still retain sufficient porosity to allow pressure-driven flow in the low {mu}L/min range. Using the enzyme {gamma}-glutamyl transpeptidase ({gamma}-GT), we further evaluated the catalytic constants of the enzyme entrapped in capillary columns with different silica morphologies as a function of flowrate and backpressure using the enzyme reactor assay mode. It was found that the apparent activity of the enzyme was highest in mesoporous columns that retained high levels of enzyme. In such columns, enzyme activity increased by {approx}2-fold with increases in both flowrate (from 250 to 1000 nL/min) and backpressure generated (from 500 to 2100 psi) during the chromatographic activity assay owing to increases in k {sub cat} and decreases in K {sub M}, switching from diffusion controlled to reaction controlled conditions at ca. 2000 psi. These results suggest that columns with minimal macropore volumes (<5%) are advantageous for the entrapment of soluble proteins for bioaffinity and bioreactor chromatography.

  6. Battery Modeling

    OpenAIRE

    Jongerden, M.R.; Haverkort, B.R.

    2008-01-01

    The use of mobile devices is often limited by the capacity of the employed batteries. The battery lifetime determines how long one can use a device. Battery modeling can help to predict, and possibly extend this lifetime. Many different battery models have been developed over the years. However, with these models one can only compute lifetimes for specific discharge profiles, and not for workloads in general. In this paper, we give an overview of the different battery models that are availabl...

  7. Utilization of niching methods of genetic algorithms in nuclear reactor problems optimization; A utilizacao dos metodos de nichos dos algoritmos geneticos na otimizacao de problemas de reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner Figueiredo; Schirru, Roberto [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2000-07-01

    Genetic Algorithms (GAs) are biologically motivated adaptive systems which have been used, with good results, in function optimization. However, traditional GAs rapidly push an artificial population toward convergence. That is, all individuals in the population soon become nearly identical. Niching Methods allow genetic algorithms to maintain a population of diverse individuals. GAs that incorporate these methods are capable of locating multiple, optimal solutions within a single population. The purpose of this study is to test existing niching techniques and two methods introduced herein, bearing in mind their eventual application in nuclear reactor related problems, specially the nuclear reactor core reload one, which has multiple solutions. Tests are performed using widely known test functions and their results show that the new methods are quite promising, specially in real world problems like the nuclear reactor core reload. (author)

  8. Genetic algorithm with fuzzy clustering for optimization of nuclear reactor problems; Um algoritmo genetico com clusterizacao nebulosa para a otimizacao de problemas de reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Marcelo Dornellas; Sacco, Wagner Figueiredo; Schirru, Roberto [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2000-07-01

    Genetic Algorithms (GAs) are biologically motivated adaptive systems which have been used, with good results, in function optimization. However, traditional GAs rapidly push an artificial population toward convergence. That is, all individuals in the population soon become nearly identical. Niching Methods allow genetic algorithms to maintain a population of diverse individuals. GAs that incorporate these methods are capable of locating multiple, optimal solutions within a single population. The purpose of this study is to introduce a new niching technique based on the fuzzy clustering method FCM, bearing in mind its eventual application in nuclear reactor related problems, specially the nuclear reactor core reload one, which has multiple solutions. tests are performed using widely known test functions and their results show that the new method is quite promising, specially to a future application in real world problems like the nuclear reactor core reload. (author)

  9. Determining the optimal transmembrane gas pressure for nitrification in membrane-aerated biofilm reactors based on oxygen profile analysis.

    Science.gov (United States)

    Wang, Rongchang; Xiao, Fan; Wang, Yanan; Lewandowski, Zbigniew

    2016-09-01

    The goal of this study was to investigate the effect of transmembrane gas pressure (P g) on the specific ammonium removal rate in a membrane-aerated biofilm reactor (MABR). Our experimental results show that the specific ammonium removal rate increased from 4.98 to 9.26 gN m(-2) day(-1) when P g increased from 2 to 20 kPa in an MABR with a biofilm thickness of approximately 600 μm. However, this improvement was not linear; there was a threshold of P g separating the stronger and weaker effects of P g. The ammonium removal rate was improved less significantly when P g was over the threshold, indicating that there is an optimal threshold of P g for maximizing ammonium removal in an MABR. The change in oxygen penetration depth (d p) is less sensitive to P g in the ammonia-oxidizing active layer than in the inactive layer in membrane-aerated biofilm. The location of the P g threshold is at the same point as the thickness of the active layer on the curve of d p versus P g; thus, the active layer thickness and the optimal P g can be determined on the basis of the changes in the slope of d p to P g. PMID:27170321

  10. Optimization of operating parameters for gas-phase photocatalytic splitting of H2S by novel vermiculate packed tubular reactor.

    Science.gov (United States)

    Preethi, V; Kanmani, S

    2016-10-01

    Hydrogen production by gas-phase photocatalytic splitting of Hydrogen Sulphide (H2S) was investigated on four semiconductor photocatalysts including CuGa1.6Fe0.4O2, ZnFe2O3, (CdS + ZnS)/Fe2O3 and Ce/TiO2. The CdS and ZnS coated core shell particles (CdS + ZnS)/Fe2O3 shows the highest rate of hydrogen (H2) production under optimized conditions. Packed bed tubular reactor was used to study the performance of prepared photocatalysts. Selection of the best packing material is a key for maximum removal efficiency. Cheap, lightweight and easily adsorbing vermiculate materials were used as a novel packing material and were found to be effective in splitting H2S. Effect of various operating parameters like flow rate, sulphide concentration, catalyst dosage, light irradiation were tested and optimized for maximum H2 conversion of 92% from industrial waste H2S. PMID:27562700

  11. Thermal—hydraulic Optimization of Water—cooled Center COnductor Post for Spherical Tokamaks Reactor

    Institute of Scientific and Technical Information of China (English)

    柯严; 吴宜灿; 等

    2002-01-01

    This paper proposes a conceptual structure of segmental water-cooled Center Conductor Post(CCP) to be flexble in installment and replacement.Thermal-hydraulic optimization and sensitivity analysis of key parameters are performed based on a reference fusion transmutation system with 100MW fusion power.Numerical simulation by using a commercial code PHOENICS has been carried out to be close to the thermal-hydraulic analytical results of the CCP mid-part.

  12. Thermal-hydraulic Optimization of Water-cooled Center Conductor Post for Spherical Tokamaks Reactor

    Institute of Scientific and Technical Information of China (English)

    柯严; 吴宜灿; 黄群英; 郑善良

    2002-01-01

    This paper proposes a conceptual structure of segmental water-cooled Center Con ductor Post (CCP) to be flexible in installment and replacement. Thermal-hydraulic optimization and sensitivity analysis of key parameters are performed based on a reference fusion transmutation system with 100 MW fusion power. Numerical simulation by using a commercial code PHOEN]CS has been carried out to be close to the thermal-hydraulic analytical results of the CCP mid-part.

  13. Advanced CANDU reactor: an optimized energy source of oil sands application

    International Nuclear Information System (INIS)

    Atomic Energy of Canada Limited (AECL) is developing the ACR-700TM (Advanced CANDU Reactor-700TM) to meet customer needs for reduced capital cost, shorter construction schedule, high capacity factor while retaining the benefits of the CANDU experience base. The ACR-700 is based on the concept of CANDU horizontal fuel channels surrounded by heavy water moderator. The major innovation of this design is the use of slightly enriched uranium fuel in a CANFLEX bundle that is cooled by light water. This ensures: higher main steam pressures and temperatures providing higher thermal efficiency; a compact and simpler reactor design with reduced capital costs and shorter construction schedules; and reduced heavy water inventory compared to existing CANDU reactors. ACR-700 is not only a technically advanced and cost effective solution for electricity generating utilities, but also a low-cost, long-life and sustainable steam source for increasing Alberta's Oil Sand production rates. Currently practiced commercial surface mining and extraction of Oil Sand resources has been well established over the last three decades. But a majority of the available resources are somewhat deeper underground require in-situ extraction. Economic removal of such underground resources is now possible through the Steam Assisted Gravity Drainage (SAGD) process developed and proto-type tested in-site. SAGD requires the injection of large quantities of high-pressure steam into horizontal wells to form reduced viscosity bitumen and condensate mixture that is then collected at the surface. This paper describes joint AECL studies with CERI (Canadian Energy Research Institute) for the ACR, supplying both electricity and medium-pressure steam to an oil sands facility. The extensive oil sands deposits in northern Alberta are a very large energy resource. Currently, 30% of Canda's oil production is from the oil sands and this is expected to expand greatly over the coming decade. The bitumen deposits in the

  14. Production and optimization of biodiesel using mixed immobilized biocatalysts in packed bed reactor.

    Science.gov (United States)

    Bakkiyaraj, S; Syed, Mahin Basha; Devanesan, M G; Thangavelu, Viruthagiri

    2016-05-01

    Vegetable oils are used as raw materials for biodiesel production using transesterification reaction. Several methods for the production of biodiesel were developed using chemical (alkali and acidic compounds) and biological catalysts (lipases). Biodiesel production catalyzed by lipases is energy and cost-saving processes and is carried out at normal temperature and pressure. The need for an efficient method for screening larger number of variables has led to the adoption of statistical experimental design. In the present study, packed bed reactor was designed to study with mixed immobilized biocatalysts to have higher productivity under optimum conditions. Contrary to the single-step acyl migration mechanism, a two-step stepwise reaction mechanism involving immobilized Candida rugosa lipase and immobilized Rhizopus oryzae cells was employed for the present work. This method was chosen because enzymatic hydrolysis followed by esterification can tolerate high free fatty acid containing oils. The effects of flow rate and bed height on biodiesel yield were studied using two factors five-level central composite design (CCD) and response surface methodology (RSM). Maximum biodiesel yield of 85 and 81 % was obtained for jatropha oil and karanja oil with the optimum bed height and optimum flow rate of 32.6 cm and 1.35 L/h, and 32.6 cm and 1.36 L/h, respectively. PMID:25940482

  15. Immobilized photocatalyst structure assuring optimal light distribution in a solar reactor

    Directory of Open Access Journals (Sweden)

    A. S. El-Kalliny

    2014-02-01

    Full Text Available Immobilized TiO2 photocatalyst with a high specific surface area was prepared on stainless steel woven meshes in order to be used packed in layers for water purification. Immobilization of such a complex shape needs a special coating technique. For this purpose, dip coating and electrophoretic deposition (EPD techniques were used. The EPD technique gave the TiO2 coating films better homogeneity and adhesion, fewer cracks, and higher •OH formation than the dip coating technique. The woven mesh structure packed in layers guaranteed an efficient light-penetration in water treatment reactor. A simple equation model was used to describe the distribution of light through the mesh layers in the presence of absorbing medium (e.g., colored water with humic acids. Maximum three or four coated meshes were enough to harvest the solar UV light from 300 nm to 400 nm with a high penetration efficiency. The separation distance between the mesh layers played an important role in the efficiency of solar light penetration through the coated mesh layers, especially in case of colored water contaminated with high concentrations of humic acid.

  16. PRODUCTION OF MEDIUM-CHAIN ACYLGLYCEROLS BY LIPASE ESTERIFICATION IN PACKED BED REACTOR: PROCESS OPTIMIZATION BY RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    ZANARIAH MOHD DOM

    2014-06-01

    Full Text Available Medium-chain acylglycerols (or glycerides are formed of mono-, di- and triacylglycerol classes. In this study, an alternative method to produce MCA from esterifying palm oil fatty acid distillate (PFAD with the presence of oil palm mesocarp lipase (OPML which is a plant-sourced lipase and PFAD is also cheap by-product is developed in a packed bed reactor. The production of medium-chain acylglycerols (MCA by lipase-catalysed esterification of palm oil fatty acid distillate with glycerol are optimize in order to determine the factors that have significant effects on the reaction condition and high yield of MCA. Response surface methodology (RSM was applied to optimize the reaction conditions. The reaction conditions, namely, the reaction time (30-240 min, enzyme load (0.5-1.5 kg, silica gel load (0.2-1.0 kg, and solvent amount (200-600 vol/wt. Reaction time, enzyme loading and solvent amount strongly effect MCA synthesis (p0.05 influence on MCA yield. Best-fitting models were successfully established for MCA yield (R 2 =0.9133. The optimum MCA yield were 75% from the predicted value and 75.4% from the experimental data for 6 kg enzyme loading, a reaction time of 135min and a solvent amount of 350 vol/wt at 65ºC reaction temperature. Verification of experimental results under optimized reaction conditions were conducted, and the results agreed well with the predicted range. Esterification products (mono-, di- and triacylglycerol from the PBR were identified using Thin Layer Chromatography method. The chromatograms showed the successful fractionation of esterified products in this alternative method of process esterification.

  17. Improving the performance of the Egyptian second testing nuclear research reactor using interval type-2 fuzzy logic controller tuned by modified biogeography-based optimization

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, M.M., E-mail: M.M.Sayed@ieee.org; Saad, M.S.; Emara, H.M.; Abou El-Zahab, E.E.

    2013-09-15

    Highlights: • A modified version of the BBO was proposed. • A novel method for interval type-2 FLC design tuned by MBBO was proposed. • The performance of the ETRR-2 was improved by using IT2FLC tuned by MBBO. -- Abstract: Power stabilization is a critical issue in nuclear reactors. The conventional proportional derivative (PD) controller is currently used in the Egyptian second testing research reactor (ETRR-2). In this paper, we propose a modified biogeography-based optimization (MBBO) algorithm to design the interval type-2 fuzzy logic controller (IT2FLC) to improve the performance of the Egyptian second testing research reactor (ETRR-2). Biogeography-based optimization (BBO) is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. A modified version of the BBO is applied to design the IT2FLC to get the optimal parameters of the membership functions of the controller. We test the optimal IT2FLC obtained by modified biogeography-based optimization (MBBO) using the integral square error (ISE) and is compared with the currently used PD controller.

  18. Improving the performance of the Egyptian second testing nuclear research reactor using interval type-2 fuzzy logic controller tuned by modified biogeography-based optimization

    International Nuclear Information System (INIS)

    Highlights: • A modified version of the BBO was proposed. • A novel method for interval type-2 FLC design tuned by MBBO was proposed. • The performance of the ETRR-2 was improved by using IT2FLC tuned by MBBO. -- Abstract: Power stabilization is a critical issue in nuclear reactors. The conventional proportional derivative (PD) controller is currently used in the Egyptian second testing research reactor (ETRR-2). In this paper, we propose a modified biogeography-based optimization (MBBO) algorithm to design the interval type-2 fuzzy logic controller (IT2FLC) to improve the performance of the Egyptian second testing research reactor (ETRR-2). Biogeography-based optimization (BBO) is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. A modified version of the BBO is applied to design the IT2FLC to get the optimal parameters of the membership functions of the controller. We test the optimal IT2FLC obtained by modified biogeography-based optimization (MBBO) using the integral square error (ISE) and is compared with the currently used PD controller

  19. Optimization of the coupling of nuclear reactors and desalination systems. Final report of a coordinated research project 1999-2003

    International Nuclear Information System (INIS)

    Project (CRP) on Optimization of the Coupling of Nuclear Reactors and Desalination Systems with participation of institutes from nine Member States. The CRP was initiated as a step forward for facilitating an early deployment in developing countries, where nuclear desalination is being considered as an option to cope with fresh water deficit as well as energy in the coming decade. The CRP has enabled the IAEA and participating institutes to accumulate relevant information on the latest research and development in the field of nuclear desalination and share it with interested Member States. The CRP has produced optimum coupling configurations of nuclear and desalination systems, evaluated their performance and identified technical features, which may require further assessment for detailed specifications of large-scale nuclear desalination plants. This publication highlights the outcomes of projects under this CRP and draw lessons and suggestions for further investigation for deployment of nuclear desalination

  20. Optimization of N18 Zirconium Alloy for Fuel Cladding of Water Reactors

    Institute of Scientific and Technical Information of China (English)

    B.X. Zhou; M. Y. Yao; Z.K. Li; X.M. Wang; J. Zhoua; C.S. Long; Q. Liu; B.F. Luan

    2012-01-01

    In order to optimize the microstructure and composition of N18 zirconium alloy (Zr-1Sn-0.35Nb-0.35Fe-0.1Cr, in mass fraction, %), which was developed in China in 1990s, the effect of microstructure and composition variation on the corrosion resistance of the N18 alloy has been investigated. The autoclave corrosion tests were carried out in super heated steam at 400 ~C/10.3 MPa, in deionized water or lithiated water with 0.01 mol/L LiOH at 360 ~C/18.6 MPa. The exposure time lasted for 300-550 days according to the test temperature. The results show that the microstructure with a fine and uniform distribution of second phase particles (SPPs), and the decrease of Sn content from 1% (in mass fraction, the same as follows) to 0.8% are of benefit to improving the corrosion resistance; It is detrimental to the corrosion resistance if no Cr addition. The addition of Nb content with upper limit (0.35%) is beneficial to improving the corrosion resistance. The addition of Cu less than 0.1% shows no remarkable influence upon the corrosion resistance for N18 alloy. Comparing the corrosion resistance of the optimized N18 with other commercial zirconium alloys, such as Zircaloy-4, ZIRLO, E635 and Ell0, the former shows superior corrosion resistance in all autoclave testing conditions mentioned above. Although the data of the corrosion resistance as fuel cladding for high burn-up has not been obtained yet, it is believed that the optimized N18 alloy is promising for the candidate of fuel cladding materials as high burn-up fuel assemblies. Based on the theory that the microstructural evolution of oxide layer during corrosion process will affect the corrosion resistance of zirconium alloys, the improvement of corrosion resistance of the N18 alloy by obtaining the microstructure with nano-size and uniform distribution of SPPs, and by decreasing the content of Sn and maintaining the content of Cr is discussed.

  1. The nuclear battery

    Science.gov (United States)

    Kozier, K. S.; Rosinger, H. E.

    The evolution and present status of an Atomic Energy of Canada Limited program to develop a small, solid-state, passively cooled reactor power supply known as the Nuclear Battery is reviewed. Key technical features of the Nuclear Battery reactor core include a heat-pipe primary heat transport system, graphite neutron moderator, low-enriched uranium TRISO coated-particle fuel and the use of burnable poisons for long-term reactivity control. An external secondary heat transport system extracts useful heat energy, which may be converted into electricity in an organic Rankine cycle engine or used to produce high-pressure steam. The present reference design is capable of producing about 2400 kW(t) (about 600 kW(e) net) for 15 full-power years. Technical and safety features are described along with recent progress in component hardware development programs and market assessment work.

  2. Diagnostics of Nuclear Reactor Accidents Based on Particle Swarm Optimization Trained Neural Networks

    International Nuclear Information System (INIS)

    Automation in large, complex systems such as chemical plants, electrical power generation, aerospace and nuclear plants has been steadily increasing in the recent past. automated diagnosis and control forms a necessary part of these systems,this contains thousands of alarms processing in every component, subsystem and system. so the accurate and speed of diagnosis of faults is an important factors in operation and maintaining their health and continued operation and in reducing of repair and recovery time. using of artificial intelligence facilitates the alarm classifications and faults diagnosis to control any abnormal events during the operation cycle of the plant. thesis work uses the artificial neural network as a powerful classification tool. the work basically is has two components, the first is to effectively train the neural network using particle swarm optimization, which non-derivative based technique. to achieve proper training of the neural network to fault classification problem and comparing this technique to already existing techniques

  3. Optimizing the energy efficiency of capacitive deionization reactors working under real-world conditions.

    Science.gov (United States)

    García-Quismondo, Enrique; Santos, Cleis; Lado, Julio; Palma, Jesús; Anderson, Marc A

    2013-10-15

    Capacitive deionization (CDI) is a rapidly emerging desalination technology that promises to deliver clean water while storing energy in the electrical double layer (EDL) near a charged surface in a capacitive format. Whereas most research in this subject area has been devoted to using CDI for removing salts, little attention has been paid to the energy storage aspect of the technology. However, it is energy storage that would allow this technology to compete with other desalination processes if this energy could be stored and reused efficiently. This requires that the operational aspects of CDI be optimized with respect to energy used both during the removal of ions as well as during the regeneration cycle. This translates into the fact that currents applied during deionization (charging the EDL) will be different from those used in regeneration (discharge). This paper provides a mechanistic analysis of CDI in terms of energy consumption and energy efficiencies during the charging and discharging of the system under several scenarios. In a previous study, we proposed an operational buffer mode in which an effective separation of deionization and regeneration steps would allow one to better define the energy balance of this CDI process. This paper reports on using this concept, for optimizing energy efficiency, as well as to improve upon the electro-adsorption of ions and system lifetime. Results obtained indicate that real-world operational modes of running CDI systems promote the development of new and unexpected behavior not previously found, mainly associated with the inhomogeneous distribution of ions across the structure of the electrodes. PMID:24015835

  4. Optimization design study of an innovative divertor concept for future experimental tokamak-type fusion reactors

    International Nuclear Information System (INIS)

    The design optimization study of an innovative divertor concept for future experimental tokamak-type fusion devices is both an answer to the actual problems encountered in the multilayer divertor proposals and an illustration of a rational modelling philosophy and optimization strategy for the development of a new divertor structure. Instead of using mechanical attachment or metallurgical bonding of the protective material to the heat sink as in most actual divertor concepts, the so-called brush divertor in this study uses an array of unidirectional fibers penetrating in both the protective armor and the underling composite heat sink. Although the approach is fully concentrated on the divertor performance, including both a description of its function from the theoretical point of view and an overview of the problems related to the materials choice and evaluation, both the approach followed in the numerical modelling and the judgment of the results are thought to be valid also for other applications. Therefore the spin-off of the study must be situated in both the technological progress towards a feasible divertor solution, which introduces no additional physical uncertainties, and in the general area of the thermo-mechanical finite-element modelling on both macro-and microscale. The brush divertor itself embodies the use, and thus the modelling, of advanced materials such as tailor-made metal matrix composites and dispersion strengthened metals, and is shown to offer large potential advantages, demanding however and experimental validation under working conditions. It is clearly indicated where the need originates for an integrated experimental program which must allow to verify the basic modelling assumptions in order to arrive at the use of numerical computation as a powerful and realistic tool of structural testing and life-time prediction

  5. Optimizing the energy efficiency of capacitive deionization reactors working under real-world conditions.

    Science.gov (United States)

    García-Quismondo, Enrique; Santos, Cleis; Lado, Julio; Palma, Jesús; Anderson, Marc A

    2013-10-15

    Capacitive deionization (CDI) is a rapidly emerging desalination technology that promises to deliver clean water while storing energy in the electrical double layer (EDL) near a charged surface in a capacitive format. Whereas most research in this subject area has been devoted to using CDI for removing salts, little attention has been paid to the energy storage aspect of the technology. However, it is energy storage that would allow this technology to compete with other desalination processes if this energy could be stored and reused efficiently. This requires that the operational aspects of CDI be optimized with respect to energy used both during the removal of ions as well as during the regeneration cycle. This translates into the fact that currents applied during deionization (charging the EDL) will be different from those used in regeneration (discharge). This paper provides a mechanistic analysis of CDI in terms of energy consumption and energy efficiencies during the charging and discharging of the system under several scenarios. In a previous study, we proposed an operational buffer mode in which an effective separation of deionization and regeneration steps would allow one to better define the energy balance of this CDI process. This paper reports on using this concept, for optimizing energy efficiency, as well as to improve upon the electro-adsorption of ions and system lifetime. Results obtained indicate that real-world operational modes of running CDI systems promote the development of new and unexpected behavior not previously found, mainly associated with the inhomogeneous distribution of ions across the structure of the electrodes.

  6. 电动公交充换电站的优化运行研究%Research on Optimal Operation of Battery Swapping and Charging Station for Electric Buses

    Institute of Scientific and Technical Information of China (English)

    阳岳希; 胡泽春; 宋永华

    2012-01-01

    The optimal operation of battery swapping and charging station for electric bus involves many processes, such as bus service, battery swapping, battery charging, and so on. The daily battery swapping demand was quantitatively analyzed based on factors including the operating pattern and electricity consumption characteristics of electric buses. The optimal battery swapping order was determined for equal battery usage and charging convenience. A two-stage and a bi-objective mathematic optimization models for battery recharging with minimize charging cost as the primary objective were established, and the smoothing of the charging load curve was also considered. Other factors that have influences on optimal charging schedule such as the starting time, reserved battery number for uncertainties were analyzed. Case study results show that the proposed method can Feduce daily charging cost substantially and mitigate the impacts of charging load on the grid.%公交车充换电站的优化运行涉及公交运营、电池更换和电池充电等多个方面.考虑公交车的运行规律和耗电特性等因素,定量分析了车辆的日换电需求,并基于均衡使用电池和有利于电池充电的原则,推导了电池优化更换的顺序.以充电成本最小为首要目标,综合考虑平滑充电负荷曲线,分别建立了两阶段和双目标优化充电模型.对优化充电的起始时间、备用电池数量等因素对优化结果的影响进行了分析.算例仿真结果表明,该方法可有效降低充电成本和充电负荷对电网的影响.

  7. Paintable Battery

    OpenAIRE

    Singh, Neelam; Galande, Charudatta; Miranda, Andrea; Mathkar, Akshay; Gao, Wei; Reddy, Arava Leela Mohana; Vlad, Alexandru; Ajayan, Pulickel M.

    2012-01-01

    If the components of a battery, including electrodes, separator, electrolyte and the current collectors can be designed as paints and applied sequentially to build a complete battery, on any arbitrary surface, it would have significant impact on the design, implementation and integration of energy storage devices. Here, we establish a paradigm change in battery assembly by fabricating rechargeable Li-ion batteries solely by multi-step spray painting of its components on a variety of materials...

  8. RAMI Analysis for Designing and Optimizing Tokamak Cooling Water System (TCWS) for the ITER's Fusion Reactor

    International Nuclear Information System (INIS)

    U.S.-ITER is responsible for the design, engineering, and procurement of the Tokamak Cooling Water System (TCWS). TCWS is designed to provide cooling and baking for client systems that include the first wall/blanket, vacuum vessel, divertor, and neutral beam injector. Additional operations that support these primary functions include chemical control of water provided to client systems, draining and drying for maintenance, and leak detection/localization. TCWS interfaces with 27 systems including the secondary cooling system, which rejects this heat to the environment. TCWS transfers heat generated in the Tokamak during nominal pulsed operation - 850 MW at up to 150 C and 4.2 MPa water pressure. Impurities are diffused from in-vessel components and the vacuum vessel by water baking at 200-240 C at up to 4.4 MPa. TCWS is complex because it serves vital functions for four primary clients whose performance is critical to ITER's success and interfaces with more than 20 additional ITER systems. Conceptual design of this one-of-a-kind cooling system has been completed; however, several issues remain that must be resolved before moving to the next stage of the design process. The 2004 baseline design indicated cooling loops that have no fault tolerance for component failures. During plasma operation, each cooling loop relies on a single pump, a single pressurizer, and one heat exchanger. Consequently, failure of any of these would render TCWS inoperable, resulting in plasma shutdown. The application of reliability, availability, maintainability, and inspectability (RAMI) tools during the different stages of TCWS design is crucial for optimization purposes and for maintaining compliance with project requirements. RAMI analysis will indicate appropriate equipment redundancy that provides graceful degradation in the event of an equipment failure. This analysis helps demonstrate that using proven, commercially available equipment is better than using custom-designed equipment

  9. Optimization of operation conditions for preventing sludge bulking and enhancing the stability of aerobic granular sludge in sequencing batch reactors.

    Science.gov (United States)

    Zhou, Jun; Wang, Hongyu; Yang, Kai; Ma, Fang; Lv, Bin

    2014-01-01

    Sludge bulking caused by loss of stability is a major problem in aerobic granular sludge systems. This study investigated the feasibility of preventing sludge bulking and enhancing the stability of aerobic granular sludge in a sequencing batch reactor by optimizing operation conditions. Five operation parameters have been studied with the aim to understand their impact on sludge bulking. Increasing dissolved oxygen (DO) by raising aeration rates contributed to granule stability due to the competition advantage of non-filamentous bacteria and permeation of oxygen at high DO concentration. The ratio of polysaccharides to proteins was observed to increase as the hydraulic shear force increased. When provided with high/low organic loading rate (OLR) alternately, large and fluffy granules disintegrated, while denser round-shape granules formed. An increase of biomass concentration followed a decrease at the beginning, and stability of granules was improved. This indicated that aerobic granular sludge had the resistance of OLR. Synthetic wastewater combined highly and slowly biodegradable substrates, creating a high gradient, which inhibited the growth of filamentous bacteria and prevented granular sludge bulking. A lower chemical oxygen demand/N favored the hydrophobicity of granular sludge, which promoted with granule stability because of the lower diffusion rate of ammonia. The influence of temperature indicated a relatively low temperature was more suitable.

  10. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Shuokr Qarani [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Aziz, Hamidi Abdul, E-mail: cehamidi@eng.usm.my [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Yusoff, Mohd Suffian; Bashir, Mohammed J.K. [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia)

    2011-05-15

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH{sub 3}-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH{sub 3}-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  11. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: optimization by response surface methodology.

    Science.gov (United States)

    Aziz, Shuokr Qarani; Aziz, Hamidi Abdul; Yusoff, Mohd Suffian; Bashir, Mohammed J K

    2011-05-15

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH(3)-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1L/min and contact time of 5.5h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH(3)-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions. PMID:21420786

  12. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    International Nuclear Information System (INIS)

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH3-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH3-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  13. General arrangement design optimization of emergency response facility (TSC, OSC) in Korea next generation reactor (APR-1400)

    International Nuclear Information System (INIS)

    The accident at the Three Mile Island (TMI) led to install some data processing and display equipment to assist control room personnel in rapidly evaluating the safety status. And also to place in the plant for providing operators with technical support and an emergency response center for radiological environmental assessments and determination of recommended public protective action during emergency. In practice, most of the countries possessing nuclear power plants including USA have partially or wholly adopted US NRC regulations and guidelines for Emergency Response Facility(ERF). Also the Korea nuclear power plants are implementing or operating ERF and SPDS after analyzing US NRC regulations and guideline since TMI accident. So this paper first been reviewed Korea Regulations, US NRC published codes and standards related to ERF (TSC/OSC). Finally this paper is described the design optimization of general arrangement in emergency response facility to improve emergency response capability in Korea Next Generation Reactor(APR-1400), which are best suitable for our domestic situation and also enhance the emergency response capability of ERF

  14. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  15. B#: A battery emulator and power-profiling instrument

    OpenAIRE

    Park, C. S.; Liu, J. F.; Chou, P H

    2005-01-01

    B# (B sharp) is a programmable power supply that emulates battery behavior. It measures current load, calls a battery simulation program to compute voltage in real time, and controls a linear regulator to mimic a battery's voltage output. The instrument enables validation of battery-aware power optimization techniques with accurate, controllable, reproducible results.

  16. 基于无损二次衰减调制的电池能耗优化控制方法%Battery Energy Optimization Control Method Based on Nondestructive Two Attenuation Modulation

    Institute of Scientific and Technical Information of China (English)

    高申; 龙泽; 高诠; 龙之玥

    2015-01-01

    In the data acquisition system of multi sensors, battery power consumption and battery life to direct the life of multi sensor system and the work cycle decision, optimization research on the control method of battery energy consump⁃tion, improved battery life cycle. The traditional battery energy consumption control uses the residual energy vector proba⁃bility density distribution method, attenuation limited by battery, transmission power, control performance is not good. Put forward a kind of battery energy optimization control method for nondestructive two attenuation based on modulation. Power energy dissipation model construction of multi sensor system, considering the coordinated control strategy of battery, normal control cell and had pass charging control design, coordination control strategy of integrated power system, nondestructive two attenuation modulation, using linear feedback linearization compensation for direct control of battery energy consump⁃tion, using lossless two attenuation modulation and overload state assessment of battery, improve the control efficiency, and improve the battery working life and energy storage properties. The simulation results show that the algorithm can effective⁃ly improve the battery life cycle, reduce the energy loss of the battery, increase transmit power, superior performance.%在多传感器数据采集系统中,电池能耗和电池寿命直接决定了多传感器系统的寿命和工作周期,研究电池能耗的优化控制方法,提高电池寿命周期。传统的电池能耗控制采用能量剩余度向量概率密度分配方法,受到电池发射功率的匹配衰减限制,控制效能不好。提出一种基于无损二次衰减调制的电池能耗优化控制方法。构建多传感器系统的电源能耗耗散模型,考虑电池的协调控制策略,进行电池的正常控制和过放过充控制设计,综合发电系统的协调控制策略,进行无损二次衰减调

  17. Optimization of the moving-bed biofilm sequencing batch reactor (MBSBR) to control aeration time by kinetic computational modeling: Simulated sugar-industry wastewater treatment.

    Science.gov (United States)

    Faridnasr, Maryam; Ghanbari, Bastam; Sassani, Ardavan

    2016-05-01

    A novel approach was applied for optimization of a moving-bed biofilm sequencing batch reactor (MBSBR) to treat sugar-industry wastewater (BOD5=500-2500 and COD=750-3750 mg/L) at 2-4 h of cycle time (CT). Although the experimental data showed that MBSBR reached high BOD5 and COD removal performances, it failed to achieve the standard limits at the mentioned CTs. Thus, optimization of the reactor was rendered by kinetic computational modeling and using statistical error indicator normalized root mean square error (NRMSE). The results of NRMSE revealed that Stover-Kincannon (error=6.40%) and Grau (error=6.15%) models provide better fits to the experimental data and may be used for CT optimization in the reactor. The models predicted required CTs of 4.5, 6.5, 7 and 7.5 h for effluent standardization of 500, 1000, 1500 and 2500 mg/L influent BOD5 concentrations, respectively. Similar pattern of the experimental data also confirmed these findings.

  18. 微电网中电动汽车充电模式与换电模式的运行优化%Operation Optimization of Electric Vehicles in Battery Swapping Mode and Direct Charging Mode in Microgrid

    Institute of Scientific and Technical Information of China (English)

    张晓波; 张保会; 董梁; 关哲; 管俊; 谢芮芮

    2016-01-01

    在已知风光出力,且电网实行分时电价的前提下,分别使用充电模式和换电模式调用充电汽车蓄电池储能。充电模式以微网内燃料费用最低和外网购电费用最低为优化目标,换电模式在上述优化目标基础上增加充电购电成本最低优化目标,使用混合整数规划 CPLEX软件求解了该优化目标下的充电汽车储放能控制策略,并给出了优化运行结果。结果表明该优化方案有利于降低微网运营者的运行费用,而采用换电模式给充电汽车充电更能发挥充电汽车蓄电池逢电价高储能、逢电价低放能的作用,提高了微网的运行经济性。%On the premise of known output power of wind power and photovoltaic and time-of-use electricity price implemented in the grid,electric vehicles energy storage battery is used in the battery swapping mode and the direct charging mode.The optimization obj ective is minimum fuel cost and power cost purchased from an external grid in the direct charging mode.For the battery swapping mode,minimum recharging cost is added as the optimization obj ective on the basis of the above-mentioned optimization obj ective in battery swapping mode.The optimization obj ectives are verified using CPLEX software,the results showing that the optimization program will help reduce the operating cost of the microgrid operator.The battery swapping mode is better than the direct charging mode for using battery discharging energy when energy price is high and charging when energy price is low,thus improving the operational economy of the microgrid.

  19. Efficiency-optimized CO2 separation in IGCC power plants by water-gas shift membrane reactors

    International Nuclear Information System (INIS)

    The conversion of solid fuels such as coal and biomass into syngas in the integrated gasification combined cycle (IGCC) process is carried out at elevated pressure. Since, from a thermodynamic point of view, this is a crucial prerequisite for an efficient CO2 separation step, IGCC has great potential for incorporating CO2 separation with a low energy consumption. However, studies predict efficiency penalties in the range of 6-11 %-points depending on the respective gasification process utilized, thus revealing that the thermodynamic potential is not fully exploited. In this thesis, a specially adapted IGCC power plant concept for the optimized implementation of gas separation membranes was developed and investigated in order to evaluate the extent to which the auxiliary boundary conditions can be advantageously designed. To create a standard of comparison, a reference IGCC power plant as well as a Selexol-based CO2 scrubbing process were designed and simulated, resulting in an overall efficiency reduction from 48.0 % to 38.4 %. This corresponds to an increase of 25 % in coal consumption. The analysis of the simulation results revealed that, besides the auxiliary demand of Selexol scrubbing and CO2 compression subsequent to the low pressure regeneration of the solvent, the main contributor to the loss is the water-gas shift reaction. To reduce this high efficiency penalty, an integration concept was developed to optimize the use of the gas permeation membrane, with parameters better adapted to its special characteristics and mode of operation. The design process resulted in the use of an H2-selective membrane, which was combined with the water-gas shift reaction to create the water-gas shift membrane reactor (WGS-MR), and which was swept with recirculated flue gas at elevated pressure in countercurrent 4-End mode. In addition, the ''membrane steam recuperator'' was introduced as a new process unit and integrated to enhance the steam utilization within the entire

  20. Optimization-based power management of hybrid power systems with applications in advanced hybrid electric vehicles and wind farms with battery storage

    Science.gov (United States)

    Borhan, Hoseinali

    Modern hybrid electric vehicles and many stationary renewable power generation systems combine multiple power generating and energy storage devices to achieve an overall system-level efficiency and flexibility which is higher than their individual components. The power or energy management control, "brain" of these "hybrid" systems, determines adaptively and based on the power demand the power split between multiple subsystems and plays a critical role in overall system-level efficiency. This dissertation proposes that a receding horizon optimal control (aka Model Predictive Control) approach can be a natural and systematic framework for formulating this type of power management controls. More importantly the dissertation develops new results based on the classical theory of optimal control that allow solving the resulting optimal control problem in real-time, in spite of the complexities that arise due to several system nonlinearities and constraints. The dissertation focus is on two classes of hybrid systems: hybrid electric vehicles in the first part and wind farms with battery storage in the second part. The first part of the dissertation proposes and fully develops a real-time optimization-based power management strategy for hybrid electric vehicles. Current industry practice uses rule-based control techniques with "else-then-if" logic and look-up maps and tables in the power management of production hybrid vehicles. These algorithms are not guaranteed to result in the best possible fuel economy and there exists a gap between their performance and a minimum possible fuel economy benchmark. Furthermore, considerable time and effort are spent calibrating the control system in the vehicle development phase, and there is little flexibility in real-time handling of constraints and re-optimization of the system operation in the event of changing operating conditions and varying parameters. In addition, a proliferation of different powertrain configurations may

  1. Materials accounting in a fast-breeder-reactor fuels-reprocessing facility: optimal allocation of measurement uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Dayem, H.A.; Ostenak, C.A.; Gutmacher, R.G.; Kern, E.A.; Markin, J.T.; Martinez, D.P.; Thomas, C.C. Jr.

    1982-07-01

    This report describes the conceptual design of a materials accounting system for the feed preparation and chemical separations processes of a fast breeder reactor spent-fuel reprocessing facility. For the proposed accounting system, optimization techniques are used to calculate instrument measurement uncertainties that meet four different accounting performance goals while minimizing the total development cost of instrument systems. We identify instruments that require development to meet performance goals and measurement uncertainty components that dominate the materials balance variance. Materials accounting in the feed preparation process is complicated by large in-process inventories and spent-fuel assembly inputs that are difficult to measure. To meet 8 kg of plutonium abrupt and 40 kg of plutonium protracted loss-detection goals, materials accounting in the chemical separations process requires: process tank volume and concentration measurements having a precision less than or equal to 1%; accountability and plutonium sample tank volume measurements having a precision less than or equal to 0.3%, a shortterm correlated error less than or equal to 0.04%, and a long-term correlated error less than or equal to 0.04%; and accountability and plutonium sample tank concentration measurements having a precision less than or equal to 0.4%, a short-term correlated error less than or equal to 0.1%, and a long-term correlated error less than or equal to 0.05%. The effects of process design on materials accounting are identified. Major areas of concern include the voloxidizer, the continuous dissolver, and the accountability tank.

  2. Materials accounting in a fast-breeder-reactor fuels-reprocessing facility: optimal allocation of measurement uncertainties

    International Nuclear Information System (INIS)

    This report describes the conceptual design of a materials accounting system for the feed preparation and chemical separations processes of a fast breeder reactor spent-fuel reprocessing facility. For the proposed accounting system, optimization techniques are used to calculate instrument measurement uncertainties that meet four different accounting performance goals while minimizing the total development cost of instrument systems. We identify instruments that require development to meet performance goals and measurement uncertainty components that dominate the materials balance variance. Materials accounting in the feed preparation process is complicated by large in-process inventories and spent-fuel assembly inputs that are difficult to measure. To meet 8 kg of plutonium abrupt and 40 kg of plutonium protracted loss-detection goals, materials accounting in the chemical separations process requires: process tank volume and concentration measurements having a precision less than or equal to 1%; accountability and plutonium sample tank volume measurements having a precision less than or equal to 0.3%, a shortterm correlated error less than or equal to 0.04%, and a long-term correlated error less than or equal to 0.04%; and accountability and plutonium sample tank concentration measurements having a precision less than or equal to 0.4%, a short-term correlated error less than or equal to 0.1%, and a long-term correlated error less than or equal to 0.05%. The effects of process design on materials accounting are identified. Major areas of concern include the voloxidizer, the continuous dissolver, and the accountability tank

  3. A Micro-Grid Battery Storage Management

    DEFF Research Database (Denmark)

    Mahat, Pukar; Escribano Jiménez, Jorge; Moldes, Eloy Rodríguez;

    2013-01-01

    systems under its administration. This paper presents an optimized scheduling of a micro-grid battery storage system that takes into account the next-day forecasted load and generation profiles and spot electricity prices. Simulation results show that the battery system can be scheduled close to optimal...

  4. Preparation of Prussian Blue Submicron Particles with a Pore Structure by Two-Step Optimization for Na-Ion Battery Cathodes.

    Science.gov (United States)

    Chen, Renjie; Huang, Yongxin; Xie, Man; Zhang, Qianyun; Zhang, XiaoXiao; Li, Li; Wu, Feng

    2016-06-29

    Traditional Prussian blue (Fe4[Fe(CN)6]3) synthesized by simple rapid precipitation shows poor electrochemical performance because of the presence of vacancies occupied by coordinated water. When the precipitation rate is reduced and polyvinylpyrrolidone K-30 is added as a surface active agent, the as-prepared Prussian blue has fewer vacancies in the crystal structure than in that of traditional Prussian blue. It has a well-defined face-centered-cubic structure, which can provide large channels for Na(+) insertion/extraction. The material, synthesized by slow precipitation, has an initial discharge capacity of 113 mA h g(-1) and maintains 93 mA h g(-1) under a current density of 50 mA g(-1) after 150 charge-discharge cycles. After further optimization by a chemical etching method, the complex nanoporous structure of Prussian blue has a high Brunauer-Emmett-Teller surface area and a stable structure to achieve high specific capacity and long cycle life. Surprisingly, the electrode shows an initial discharge capacity of 115 mA h g(-1) and a Coulombic efficiency of approximately 100% with capacity retention of 96% after 150 cycles. Experimental results show that Prussian blue can also be used as a cathode for Na-ion batteries. PMID:27267656

  5. Optimal Switching Table-Based Sliding Mode Control of an Energy Recovery Li-Ion Power Accumulator Battery Pack Testing System

    Directory of Open Access Journals (Sweden)

    Kil To Chong

    2013-10-01

    Full Text Available The main objective of the present work is to apply a sliding mode controller (SMC to medium voltage and high power output energy recovery Li-ion power accumulator battery pack testing systems (ERLPABTSs, which are composed of a three-level neutral-point-clamped (NPC three-phase voltage source inverter (VSI and a two-level buck-boost converter without an isolating transformer. An inner current decoupled control scheme for the aforementioned system is proposed and two sliding mode planes for active and reactive current control are designed based on the control scheme. An optimized switching table for current convergence is used according to the error sign of the equivalent input voltage and feedback voltage. The proposed ERLPABTS could be used to integrate discharging energy into the power grid when performing high accuracy current testing. The active and reactive power references for the grid-connected inverter are determined based on the discharging energy from the DC-DC converter. Simulations and experiments on a laboratory hardware platform using a 175 kW insulated gate bipolar transistor (IGBT-based ERLPABTS have been implemented and verified, and the performance is found satisfactory and superior to conventional ERLPABPTS.

  6. Combining Optimized Particle Morphology with a Niobium-Based Coating for Long Cycling-Life, High-Voltage Lithium-Ion Batteries.

    Science.gov (United States)

    Gabrielli, Giulio; Axmann, Peter; Diemant, Thomas; Behm, Rolf Jürgen; Wohlfahrt-Mehrens, Margret

    2016-07-01

    Morphologically optimized LiNi0.5 Mn1.5 O4 (LMNO-0) particles were treated with LiNbO3 to prepare a homogeneously coated material (LMNO-Nb) as cathode in batteries. Graphite/LMNO-Nb full cells present a twofold higher cycling life than cells assembled using uncoated LMNO-0 (graphite/LMNO-0 cell): Graphite/LMNO-0 cells achieve 80 % of the initial capacity after more than 300 cycles whereas for graphite/LMNO-Nb cells this is the case for more than 600 cycles. Impedance spectroscopy measurements reveal significantly lower film and charge-transfer resistances for graphite/LMNO-Nb cells than for graphite/LMNO-0 cells during cycling. Reduced resistances suggest slower aging related to film thickening and increase of charge-transfer resistances when using LMNO-Nb cathodes. Tests at 45 °C confirm the good electrochemical performance of the investigated graphite/LMNO cells while the cycling stability of full cells is considerably lowered under these conditions. PMID:27254109

  7. Fuel management optimization in pressure water reactors with hexagonal geometry using hill climbing method; Optimizacion de la gestion de combustible en reactores de agua a presion con geometria hexagonal usando el metodo escalador de colina

    Energy Technology Data Exchange (ETDEWEB)

    Andres Diaz, J.; Quintero, Ruben; Melian, Manuel [Centro de Investigaciones Tecnologicas, Nucleares y Ambientales, La Habana (Cuba). E-mail: jadiaz@ctn.isctn.edu.cu; Rosete, Alejandro [Centro de Estudios de Ingenieria de Sistemas (CEIS), La Habana (Cuba). E-mail: rosete@ceis.ispjae.edu.cu

    2000-07-01

    In this work the general-purpose optimization method, Hill Climbing, was applied to the Fuel Management Optimization problem in PWR reactors, WWER type. They were carried out a series of experiments in order to study the performance of Hill Climbing. It was proven two starting point for initialize the search: a reload configuration by project and a reload configuration generated with the application of a minimal knowledge of the problem. It was also studied the effect of imposing constraints based on the physics of the reactor in order to reduce the number of possible solutions to be generated. The operator used in Hill Climbing was defined as a binary exchange of fuel assemblies. For the simulation of each generated configuration, the tridimensional simulator program SPPS-1 was used. It was formulated an objective function with power peaking constraint to guide the search. As results, a methodology ws proposed for the In-core Fuel Management Optimization in hexagonal geometry, and the feasibility of the application of the Hill Climbing to this type of problem was demonstrated. (author)

  8. Efficiency calculations and optimization analysis of a solar reactor for the high temperature step of the zinc/zinc-oxide thermochemical redox cycle

    Energy Technology Data Exchange (ETDEWEB)

    Haussener, S.

    2007-03-15

    A solar reactor for the first step of the zinc/zinc-oxide thermochemical redox cycle is analysed and dimensioned in terms of maximization of efficiency and reaction conversion. Zinc-oxide particles carried in an inert carrier gas, in our case argon, enter the reactor in absorber tubes and are heated by concentrated solar radiation mainly due to radiative heat transfer. The particles dissociate and, in case of complete conversion, a gas mixture of argon, zinc and oxygen leaves the reactor. The aim of this study is to find an optimal design of the reactor regarding efficiency, materials and economics. The number of absorber tubes and their dimensions, the cavity dimension and its material as well as the operating conditions should be determined. Therefore 2D and 3D simulations of an 8 kW reactor are implemented. The gases are modeled as ideal gases with temperature-dependent properties. Absorption and scattering of the particle gas mixture are calculated by Mie-theory. Radiative heat transfer is included in the simulation and implemented with the aid of the discrete ordinates (DO) method. The mixture is modeled as ideal mixture and the reaction with an Arrhenius-type ansatz. Temperature distribution, reaction efficiency (heat used for zinc-oxide reaction divided by input) and tube efficiency (heat going into absorber tubes divided by input) as well as reaction conversion are analyzed to find the most promising reactor design. The results show that the most significant factors for efficiencies, conversion and absorber fluid temperature are concentration of the solar incoming radiation, zinc-oxide mass flow, the number of tubes and their dimension. Higher concentration leads to solely positive effects. Zinc-oxide mass flow variations indicate the existence of an optimal flow rate for each reactor design which maximizes efficiencies and conversion. Higher zinc-oxide mass flow leads, on one hand, to higher tube efficiency but on the other hand to lower temperatures in

  9. Optimization of the distribution of bars with gadolinium oxide in reactor fuel elements PWR; Optimizacion de la distribucion de barras con oxido de gadolinio en elementos combustibles para reactores PWR

    Energy Technology Data Exchange (ETDEWEB)

    Melgar Santa Cecilia, P. A.; Velazquez, J.; Ahnert Iglesias, C.

    2014-07-01

    In the schemes of low leakage, currently used in the majority of PWR reactors, it makes use of absorbent consumables for the effective control of the factors of peak, the critical concentration of initial boron and the moderator temperature coefficient. One of the most used absorbing is the oxide of gadolinium, which is integrated within the fuel pickup. Occurs a process of optimization of fuel elements with oxide of gadolinium, which allows for a smaller number of configurations with a low peak factor for bar. (Author)

  10. Experimental Validation of Passive Safety System Models: Application to Design and Optimization of Fluoride-Salt-Cooled, High-Temperature Reactors

    Science.gov (United States)

    Zweibaum, Nicolas

    The development of advanced nuclear reactor technology requires understanding of complex, integrated systems that exhibit novel phenomenology under normal and accident conditions. The advent of passive safety systems and enhanced modular construction methods requires the development and use of new frameworks to predict the behavior of advanced nuclear reactors, both from a safety standpoint and from an environmental impact perspective. This dissertation introduces such frameworks for scaling of integral effects tests for natural circulation in fluoride-salt-cooled, high-temperature reactors (FHRs) to validate evaluation models (EMs) for system behavior; subsequent reliability assessment of passive, natural- circulation-driven decay heat removal systems, using these validated models; evaluation of life cycle carbon dioxide emissions as a key environmental impact metric; and recommendations for further work to apply these frameworks in the development and optimization of advanced nuclear reactor designs. In this study, the developed frameworks are applied to the analysis of the Mark 1 pebble-bed FHR (Mk1 PB-FHR) under current investigation at the University of California, Berkeley (UCB). (Abstract shortened by UMI.).

  11. Application of response surface methodology to optimize the operational parameters for enhanced removal efficiency of organic matter and nitrogen: moving bed biofilm reactor.

    Science.gov (United States)

    Barwal, Anjali; Chaudhary, Rubina

    2016-05-01

    An attempt of response surface methodology (RSM) has been made for more effective utilization and optimization for considerable reduction of operational conditions such as reaction time, aeration time, energy consumption, etc. for municipal wastewater treatment process using moving bed biofilm reactor (MBBR). A mathematical-statistical model was developed for the second-order response surface through the fit of a polynomial function and a central composite design (CCD) in the form of a full factorial design. CCD was employed to assess the interactive effects of the three main independent operational parameters, including biocarrier filling rate (0-70 %), aeration rate (0.21-0.42 m(3) h(-1)), and reactor run time (1-15 days), on the removal efficiency of chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total Kjeldahl nitrogen (TKN). Analysis of variance expressed a high coefficient of determination (R (2) = 0.84-0.95), thereby indicating that the model is significant. Using a desirability function for the highest COD (93 %), BOD (96 %), and TKN (69 %) removal, the optimum carrier filling rate, aeration rate, and reactor run time were identified to be 40 %, 0.21 m(3) h(-1), and 7 days, respectively. It shows that RSM can be a suitable method to optimize the operational parameters of MBBR with enhanced removal efficiency and less power consumption. PMID:26857006

  12. Application of response surface methodology to optimize the operational parameters for enhanced removal efficiency of organic matter and nitrogen: moving bed biofilm reactor.

    Science.gov (United States)

    Barwal, Anjali; Chaudhary, Rubina

    2016-05-01

    An attempt of response surface methodology (RSM) has been made for more effective utilization and optimization for considerable reduction of operational conditions such as reaction time, aeration time, energy consumption, etc. for municipal wastewater treatment process using moving bed biofilm reactor (MBBR). A mathematical-statistical model was developed for the second-order response surface through the fit of a polynomial function and a central composite design (CCD) in the form of a full factorial design. CCD was employed to assess the interactive effects of the three main independent operational parameters, including biocarrier filling rate (0-70 %), aeration rate (0.21-0.42 m(3) h(-1)), and reactor run time (1-15 days), on the removal efficiency of chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total Kjeldahl nitrogen (TKN). Analysis of variance expressed a high coefficient of determination (R (2) = 0.84-0.95), thereby indicating that the model is significant. Using a desirability function for the highest COD (93 %), BOD (96 %), and TKN (69 %) removal, the optimum carrier filling rate, aeration rate, and reactor run time were identified to be 40 %, 0.21 m(3) h(-1), and 7 days, respectively. It shows that RSM can be a suitable method to optimize the operational parameters of MBBR with enhanced removal efficiency and less power consumption.

  13. 基于线性优化的电动汽车换电站最优充放电策略%An Optimal Charging/Discharging Strategy for Electric Vehicle Battery Swapping Stations Based on Linear Optimization

    Institute of Scientific and Technical Information of China (English)

    孙伟卿; 王承民; 曾平良; 张焰

    2014-01-01

    The charging and discharging activities of electric vehicles (EV) can exert significant effects on the safety and economy of power system operation.This paper first compares and analyzes three most common EV battery charging modes. Then,based on the time-of-use (TOU) pricing mechanism,the operation and arbitration modes of electric vehicle battery swapping stations (EVBSS) are analyzed,and the benefit function of the EVBSS is proposed.Then,based on definite simplified on assumptions,taking the maximum operating income of EVBSS as the objective function,a linear programming model for EVBSS optimal charge/discharge strategy is established and solved.Finally,it is verified at two different energy pricings.Case study shows that the optimization model proposed is simple and effective.The work of this paper can help EVBSS operators gain maximum economic benefits and give evidence for grid management departments on EVBSS management and dispatching.%电动汽车的充放电行为会对电网运行的安全性和经济性产生重要影响。文中首先比较和分析3种常用充电模式的特点与适用场合。其次,基于分时电价机制,分析电动汽车换电站的运营与盈利模式,并以此为依据建立换电站的收益函数。然后,基于一定的简化和假设条件,以换电站运营收益最大化为目标函数,兼顾各类运营约束条件,建立换电站最优充放电策略的线性优化模型。最后,以2种电价定价方式验证建立的模型。算例表明,文中提出的优化模型简单有效,所得研究结果可以帮助电动汽车换电站运营方获得最大经济收益,同时也可以为电网管理部门对换电站的管理与调度提供依据。

  14. Fuel composition optimization in a 78-element fuel bundle for use in a pressure tube type supercritical water-cooled reactor

    International Nuclear Information System (INIS)

    A 78-element fuel bundle containing a plutonium-thorium fuel mixture has been proposed for a Generation IV pressure tube type supercritical water-cooled reactor. In this work, using a lattice cell model created with the code DRAGON,the lattice pitch, fuel composition (fraction of PuO2 in ThO2) and radial enrichment profile of the 78-element bundle is optimized using a merit function and a metaheuristic search algorithm.The merit function is designed such that the optimal fuel maximizes fuel utilization while minimizing peak element ratings and coolant void reactivity. A radial enrichment profile of 10 wt%, 11 wt% and 20 wt% PuO2 (inner to outer ring) with a lattice pitch of 25.0 cm was found to provide the optimal merit score based on the aforementioned criteria. (author)

  15. Models for Battery Reliability and Lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G. H.; Neubauer, J.; Pesaran, A.

    2014-03-01

    Models describing battery degradation physics are needed to more accurately understand how battery usage and next-generation battery designs can be optimized for performance and lifetime. Such lifetime models may also reduce the cost of battery aging experiments and shorten the time required to validate battery lifetime. Models for chemical degradation and mechanical stress are reviewed. Experimental analysis of aging data from a commercial iron-phosphate lithium-ion (Li-ion) cell elucidates the relative importance of several mechanical stress-induced degradation mechanisms.

  16. Simulation and optimization of an organic-impurity oxidization reactor with a fixed porous bed and an electric heating element

    Science.gov (United States)

    Gnezdilov, N. N.; Dobrego, K. V.; Kozlov, I. M.; Shmelev, E. S.

    2006-09-01

    A reactor for oxidization of low-caloric-value organic impurities contained in the air has been simulated. It comprises a tube with a recuperator, filled with a porous carcass mix, and includes a heating element. The influence of the heating-element placement, the heat losses through the upper cover of the reactor, the flow rate of a gas mixture, and the power of the heater on the maximum temperatures of the porous carcass and the gas and on the concentration of the incompletely oxidized organic impurity at the output of the reactor has been investigated. It is shown that, to burn an impurity completely, it will suffice to heat the gas δTe to 300 K. It has been established that it is best to place a heater at the level of the upper cut of the inner tube of the reactor.

  17. ANAEROBIC/AEROBIC BIODEGRADATION OF PENTACHLOROPHENOL USING GAC FLUIDIXED BED REACTORS: OPTIMIZATION OF THE EMPTY BED CONTACT TIME

    Science.gov (United States)

    An integrated reactor system has been developed to remediate pentachlorophenol (PCP) containing wastes using sequential anaerobic and aerobic biodegradation. Anaerobically, PCP was degraded to approximately equimolar concentrations (>99%) of chlorophenol (CP) in a granular activa...

  18. Control of the sulfide (S2-) concentration for optimal zinc removal by sulfide precipitation in a continuously stirred tank reactor

    NARCIS (Netherlands)

    Veeken, A.H.M.; Akoto, L.; Pol, L.W.H.; Weijma, J.

    2003-01-01

    Precipitation of Zn2+ with S2− was studied at room temperature in a continuously stirred tank reactor of 0.5 l to which solutions of ZnSO4 (800–5800 mg Zn2+/l) and Na2S were supplied. The pH was controlled at 6.5 and S2− concentration in the reactor was controlled at set point values ranging from 3.

  19. Safety analysis and optimization of the core fuel reloading for the Moroccan TRIGA Mark-II reactor

    International Nuclear Information System (INIS)

    Highlights: • Additional fresh fuel elements must be added to the reactor core. • TRIGA reactor could safely operate around 2 MW power with 12% fuel elements. • Thermal–hydraulic parameters were calculated and the safety margins are respected. • The 12% fuel elements will have no influence on the safety of the reactor. - Abstract: The Moroccan TRIGA MARK II reactor core is loaded with 8.5% in weight of uranium standard fuel elements. Additional fresh fuel elements must periodically be added to the core in order to remedy the observed low power and to return to the initial reactivity excess at the End Of Cycle. 12%-uranium fuel elements are available to relatively improve the short fuel lifetime associated with standard TRIGA elements. These elements have the same dimensions as standards elements, but with different uranium weight. The objective in this study is to demonstrate that the Moroccan TRIGA reactor could safely operate, around 2 MW power, with new configurations containing these 12% fuel elements. For this purpose, different safety related thermal–hydraulic parameters have been calculated in order to ensure that the safety margins are largely respected. Therefore, the PARET model for this TRIGA reactor that was previously developed and combined with the MCNP transport code in order to calculate the 3-D temperature distribution in the core and all the most important parameters like the axial distribution of DNBR (Departure from Nucleate Boiling Ratio) across the hottest channel. The most important conclusion is that the 12% fuel elements utilization will have no influence on the safety of the reactor while working around 2 MW power especially for configurations based on insertions in C and D-rings

  20. Applications of porous electrodes to metal-ion removal and the design of battery systems

    Energy Technology Data Exchange (ETDEWEB)

    Trost, G.G.

    1983-09-01

    This dissertation treats the use of porous electrodes as electrochemical reactors for the removal of dilute metal ions. A methodology for the scale-up of porous electrodes used in battery applications is given. Removal of 4 ..mu..g Pb/cc in 1 M sulfuric acid was investigated in atmospheric and high-pressure, flow-through porous reactors. The atmospheric reactor used a reticulated vitreous carbon porous bed coated in situ with a mercury film. Best results show 98% removal of lead from the feed stream. Results are summarized in a dimensionless plot of Sherwood number vs Peclet number. High-pressure, porous-electrode experiments were performed to investigate the effect of pressure on the current efficiency. Pressures were varied up to 120 bar on electrode beds of copper or lead-coated spheres. The copper spheres showed high hydrogen evolution rates which inhibited lead deposition, even at high cathodic overpotentials. Use of lead spheres inhibited hydrogen evolution but often resulted in the formation of lead sulfate layers; these layers were difficult to reduce back to lead. Experimental data of one-dimensional porous battery electrodes are combined with a model for the current collector and cell connectors to predict ultimate specific energy and maximum specific power for complete battery systems. Discharge behavior of the plate as a whole is first presented as a function of depth of discharge. These results are combined with the voltage and weight penalties of the interconnecting bus and post, positive and negative active material, cell container, etc. to give specific results for the lithium-aluminum/iron sulfide high-temperature battery. Subject to variation is the number of positive electrodes, grid conductivity, minimum current-collector weight, and total delivered capacity. The battery can be optimized for maximum energy or power, or a compromise design may be selected.

  1. Applications of porous electrodes to metal-ion removal and the design of battery systems

    International Nuclear Information System (INIS)

    This dissertation treats the use of porous electrodes as electrochemical reactors for the removal of dilute metal ions. A methodology for the scale-up of porous electrodes used in battery applications is given. Removal of 4 μg Pb/cc in 1 M sulfuric acid was investigated in atmospheric and high-pressure, flow-through porous reactors. The atmospheric reactor used a reticulated vitreous carbon porous bed coated in situ with a mercury film. Best results show 98% removal of lead from the feed stream. Results are summarized in a dimensionless plot of Sherwood number vs Peclet number. High-pressure, porous-electrode experiments were performed to investigate the effect of pressure on the current efficiency. Pressures were varied up to 120 bar on electrode beds of copper or lead-coated spheres. The copper spheres showed high hydrogen evolution rates which inhibited lead deposition, even at high cathodic overpotentials. Use of lead spheres inhibited hydrogen evolution but often resulted in the formation of lead sulfate layers; these layers were difficult to reduce back to lead. Experimental data of one-dimensional porous battery electrodes are combined with a model for the current collector and cell connectors to predict ultimate specific energy and maximum specific power for complete battery systems. Discharge behavior of the plate as a whole is first presented as a function of depth of discharge. These results are combined with the voltage and weight penalties of the interconnecting bus and post, positive and negative active material, cell container, etc. to give specific results for the lithium-aluminum/iron sulfide high-temperature battery. Subject to variation is the number of positive electrodes, grid conductivity, minimum current-collector weight, and total delivered capacity. The battery can be optimized for maximum energy or power, or a compromise design may be selected

  2. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  3. 电动汽车高渗透率的应对策略及换电站的最优规划%Responsive schemes to high penetration of electric vehicles and optimal planning of battery swap stations

    Institute of Scientific and Technical Information of China (English)

    曾正; 赵荣祥; 杨欢; 金磊

    2012-01-01

    针对传统配电网对电动汽车高渗透率的应对方案进行了研究.分析、对比并评价了峰谷电价调节方案、电动汽车和电网之间交互(V2G)方案和换电池方案,结果表明换电池方案具有明显的技术经济优势.同时认为微电网是实现换电站低碳、绿色、高效运行的一种有效方式,提出了一种以运行成本最低为目标,以功率平衡、电池管理、安装容量为约束的微电网型换电站中各分布式电源的最优规划模型.最后,利用一个数值算例验证了所提模型的有效性.%The responsive schemes of distribution network to the high penetration of electric vehicles are investigated. Three schemes are analyzed, compared and evaluated, i.e. peak-valley price regulation, V2G (Vehicle to Grid) and battery swap. Results show that,the battery swap scheme has obvious technical and economic advantages. The microgrid is considered as the best way to realize the green operation of battery swap stations with low emission and high efficiency. An optimal planning model is presented for the distribution of power sources in the microgrid for battery swap stations, which takes the minimal operating cost as its objective and the power balance,battery management and installation capacity as its constraints. A numerical case study verifies its effectiveness and validity.

  4. Low-order model of the Loss-of-Fluid Test (LOFT) reactor plant for use in Kalman filter-based optimal estimators

    International Nuclear Information System (INIS)

    A low-order, nonlinear model of the Loss-of-Fluid Test (LOFT) reactor plant, for use in Kalman filter estimators, is developed, described, and evaluated. This model consists of 31 differential equations and represents all major subsystems of both the primary and secondary sides of the LOFT plant. Comparisons between model calculations and available LOFT power range testing transients demonstrate the accuracy of the low-order model. The nonlinear model is numerically linearized for future implementation in Kalman filter and optimal control algorithms. The linearized model is shown to be an adequate representation of the nonlinear plant dynamics

  5. STAR-H2: a long-refueling interval battery reactor for hydrogen and water supply to cities of developing countries

    International Nuclear Information System (INIS)

    The STAR-H2 concept is devised to attain Gen-IV goals by responding to foreseen mid century needs and market conditions. It is targeted for support of urban centers in developing countries and is designed to fit within a hierarchical hub-spoke architecture based on regional fuel cycle centers, nuclear fuel and hydrogen as long distance energy carriers and distributed electricity generation to mesh with urban energy distribution infrastructures using grid delivery of electricity, hydrogen, potable water, and communications (and sewage return) through a common grid of easements. Long (20 year) refueling interval and full core cassette refueling supported from client country consortia-owned regional fuel cycle (front and back end) service centers, operating under international oversight are intended to make nuclear-based energy security available to countries which don't wish to emplace an indigenous front to back fuel cycle infrastructure. The regional centers, infrequent cassette refueling and full transuranic recycle (both reload and spent fuel cassettes meet the spent fuel standard of self protection) are intended to provide barriers to misuse of materials and facilities for military purposes. Fuel cassette refueling and shipments are conducted by Regional Center personnel. Reactor fissile self sufficient operation and full transuranic multi recycle both extracts the full energy content of the uranium ore, and consigns only fission products to waste. Small to mid sizing permits incremental deployments where capital financing is dear and/or indigenous infrastructure is at an early stage of development. Modular construction, factory fabrication, and delivery of a turnkey heat source reactor to the client's site where a non safety grade balance of plant has already been emplaced by local labor to local standards will facilitate rapid assembly and initiation of revenue generation. The concept employs extensive levels of passive safety to be consistent with a worldwide

  6. 含电动汽车换电站的微电网孤岛运行优化%Optimal operation of islanded microgrid with battery swap stations

    Institute of Scientific and Technical Information of China (English)

    曹一家; 苗轶群; 江全元

    2012-01-01

    The intermittence of renewable power supply , such as PV (PhotoVoltaic) and wind power, may result in power surplus or shortfall in islanded microgrid. The important components of microgrid, such as ESS(Energy Storage Station),BSS(Battery Swap Station).Uninterruptible Load),etc.,are analyzed and modeled, and with the constrains of power balance and reserve,the optimal operation model of microgrid with BSSs, ESSs or Ils is established. CPLEX is applied to solve this MILP(Mixed Integer Linear Programming) problem. Case study is carried out respectively for microgrid with BSS and that with ESS,which shows that,through coordinated optimization, the islanded microgrid with BSS as the energy storage device is cheaper and more reliable,and integrates more renewable energy sources.%由于风电、光伏等可再生能源具有间歇性,独立运行的微电网会经常出现功率缺额或过剩,给系统运行带来不利影响.对微电网内重要单元,如电池储能电站、电动汽车换电站、可中断负荷等分别进行了分析并建模,结合系统功率平衡、备用需求等约束,建立微电网独立运行优化模型,利用CPLEX软件求解该混合整数规划问题.算例中对以电动汽车换电站和电池储能电站作为储能单元的微电网分别进行讨论,结果表明,相比传统电池储能电站,电动汽车换电站作为储能装置,通过协调优化,可以提高微电网的可再生能源接纳能力,提高微电网可靠性,并更具经济性.

  7. OPTIMIZATION OF HYDRAULIC RETENTION TIME (HRT FOR RAW SUGARMILL WASTEWATER USING ANAEROBIC SEQUENTIAL BATCH REACTOR (AnSBR

    Directory of Open Access Journals (Sweden)

    Dr. S. JAYANTHI

    2013-04-01

    Full Text Available Sugar Industries in India generate about 1000 litres of wastewater for every tonne of sugarcane crushed during the manufacturing process of white crystals i.e. Sugar. There are various biological treatments for treating the wastewater of which here AnSBR is used. Anaerobic Sequential Batch Reactor (AnSBR was operated in mesophillic condition (27°C - 35°C for the treatment of Sugar mill wastewater. The study was initiated by studying the characteristics of the wastewater for the parameters such as pH, Chlorides, Acidity, Alkalinity, Total Solids, Suspended Solids, Total Dissolve Solids, Volatile Solids, Chemical Oxygen Demand (COD and Volatile Fatty Acids. The treatment of the sugar mill wastewater for the production of bio-methane gas is to be carried out in AnSBR at lab scale at room temperature with a volume of 3.5 Litres. The reactors are to be operated in 8 hours cyclic steps for different Hydraulic Retention Time (HRT such as 36, 48 and 72. Four steps involved during the 8 hours operation a Feeding Time (10 mins b Decanting time (10 mins c Reaction time (5.6 hours d Settling time (2 hours. AnSBR was operated in 8hr cyclic steps for 36, 48, 72 hrs HRT. The efficiency of the reactor was determined on basis of the maximum gas production by varying sequence lengths.OLR and HRTs. After 30 days, the AnSBR reactor could able to start with successful granulation. Optimum HRT was found to be 48 hrs at optimum HRT the COD removal % of 92 with a gas yield of 6.7828 L/L.day. The performance of reactor was considerably increased to a tune of 92%.

  8. Análisis para la modelación y optimización geométrica de un reactor tipo tornillo sin-fin empleando el método de grafos dicromáticos//Analysis for geometric modeling and optimization of a worm type reactor using the method of dichromatic graph

    Directory of Open Access Journals (Sweden)

    Armando Díaz-Concepción

    2015-09-01

    Full Text Available En el presente trabajo se realiza la modelación, simulación y optimización de un reactor utilizado en las plantas para la obtención de un alimento animal, sobre la base de la predigestión del bagacillo de caña y el hidróxido de calcio en presencia de vapor denominado PREDICAL utilizando grafos dicromáticos. Se obtuvo el modelo matemático para el diseño del reactor, donde se vinculan las variables geométricas y tecnológicas. El modelo formulado permitió la optimización de la variable costo a partir de minimizar la variable geométrica diámetro exterior del reactor. Palabras claves: modelación reactor tipo tornillo sinfin, grafos dicromáticos, modelo matemático________________________________________________________________________________AbstractThe present work performs modeling, simulation and optimization of a reactor used in plants for the obtencion of animal feed. It's made on the basis of pre-digestion of cane bagasse and calcium hydroxide in the presence of steam called PREDICAL and using dichromatic graphs. It was achieved the mathematical model for the design of the reactor, where are linked geometric and technological variables. The model developed allowed cost optimization based on minimize the geometric variable outside diameter of the reactor. Key words: worm type reactor modeling, dichromatic graphs, mathematical model.

  9. Optimal Load Distribution of Microgrid With Energy Storage System Composed of Vanadium Redox Flow Battery%含钒电池储能的微电网负荷优化分配

    Institute of Scientific and Technical Information of China (English)

    陈光堂; 邱晓燕; 林伟

    2012-01-01

    储能系统是微电网的重要组成部分,其对微电网的稳定性、经济性与安全性有着非常重要的影响.以含钒液流储能电池(vanadium redox flow battery,VRB)系统的微电网为研究对象,建立了含钒电池储能微电网多目标负荷优化分配模型.以某微电网为例,分析讨论了钒电池对微电网带来的经济效益,同时研究了运行模式、控制策略和优化目标中权重等诸多因素对微电网负荷优化分配结果的影响,验证了所建立模型的有效性.%Energy storage system is an important component of microgrid and it greatly impacts the stability, security and economic operation of microgrid. Taking a microgrid containing energy storage system composed of vanadium redox flow battery (VRB) as research object, a multi-objective load distribution optimization model of microgrid with energy storage system composed of vanadium redox flow battery (VRB) is built. The economic benefit bought to microgrid by VRB is analyzed and researched, meanwhile the influences of the factors such as operating modes, control strategy and the weights of optimization objectives on load distribution optimization of microgrid are researched too, thus the effectiveness of the built model is verified.

  10. Space and Terrestrial Power System Integration Optimization Code BRMAPS for Gas Turbine Space Power Plants With Nuclear Reactor Heat Sources

    Science.gov (United States)

    Juhasz, Albert J.

    2007-01-01

    In view of the difficult times the US and global economies are experiencing today, funds for the development of advanced fission reactors nuclear power systems for space propulsion and planetary surface applications are currently not available. However, according to the Energy Policy Act of 2005 the U.S. needs to invest in developing fission reactor technology for ground based terrestrial power plants. Such plants would make a significant contribution toward drastic reduction of worldwide greenhouse gas emissions and associated global warming. To accomplish this goal the Next Generation Nuclear Plant Project (NGNP) has been established by DOE under the Generation IV Nuclear Systems Initiative. Idaho National Laboratory (INL) was designated as the lead in the development of VHTR (Very High Temperature Reactor) and HTGR (High Temperature Gas Reactor) technology to be integrated with MMW (multi-megawatt) helium gas turbine driven electric power AC generators. However, the advantages of transmitting power in high voltage DC form over large distances are also explored in the seminar lecture series. As an attractive alternate heat source the Liquid Fluoride Reactor (LFR), pioneered at ORNL (Oak Ridge National Laboratory) in the mid 1960's, would offer much higher energy yields than current nuclear plants by using an inherently safe energy conversion scheme based on the Thorium --> U233 fuel cycle and a fission process with a negative temperature coefficient of reactivity. The power plants are to be sized to meet electric power demand during peak periods and also for providing thermal energy for hydrogen (H2) production during "off peak" periods. This approach will both supply electric power by using environmentally clean nuclear heat which does not generate green house gases, and also provide a clean fuel H2 for the future, when, due to increased global demand and the decline in discovering new deposits, our supply of liquid fossil fuels will have been used up. This is

  11. An Advanced Integrated Diffusion/Transport Method for the Design, Analysis and Optimization of the Very-High-Temperature Reactors

    International Nuclear Information System (INIS)

    The main objective of this research is to develop an integrated diffusion/transport (IDT) method to substantially improve the accuracy of nodal diffusion methods for the design and analysis of Very High Temperature Reactors (VHTR). Because of the presence of control rods in the reflector regions in the Pebble Bed Reactor (PBR-VHTR), traditional nodal diffusion methods do not accurately model these regions, within which diffusion theory breaks down in the vicinity of high neutron absorption and steep flux gradients. The IDT method uses a local transport solver based on a new incident flux response expansion method in the controlled nodes. Diffusion theory is used in the rest of the core. This approach improves the accuracy of the core solution by generating transport solutions of controlled nodes while maintaining computational efficiency by using diffusion solutions in nodes where such a treatment is sufficient. The transport method is initially developed and coupled to the reformulated 3-D nodal diffusion model in the CYNOD code for PBR core design and fuel cycle analysis. This method is also extended to the prismatic VHTR. The new method accurately captures transport effects in highly heterogeneous regions with steep flux gradients. The calculations of these nodes with transport theory avoid errors associated with spatial homogenization commonly used in diffusion methods in reactor core simulators

  12. An Advanced Integrated Diffusion/Transport Method for the Design, Analysis and Optimization of the Very-High-Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Farzad Rahnema; Dingkang Zhang; Abderrafi Ougouag; Frederick Gleicher

    2011-04-04

    The main objective of this research is to develop an integrated diffusion/transport (IDT) method to substantially improve the accuracy of nodal diffusion methods for the design and analysis of Very High Temperature Reactors (VHTR). Because of the presence of control rods in the reflector regions in the Pebble Bed Reactor (PBR-VHTR), traditional nodal diffusion methods do not accurately model these regions, within which diffusion theory breaks down in the vicinity of high neutron absorption and steep flux gradients. The IDT method uses a local transport solver based on a new incident flux response expansion method in the controlled nodes. Diffusion theory is used in the rest of the core. This approach improves the accuracy of the core solution by generating transport solutions of controlled nodes while maintaining computational efficiency by using diffusion solutions in nodes where such a treatment is sufficient. The transport method is initially developed and coupled to the reformulated 3-D nodal diffusion model in the CYNOD code for PBR core design and fuel cycle analysis. This method is also extended to the prismatic VHTR. The new method accurately captures transport effects in highly heterogeneous regions with steep flux gradients. The calculations of these nodes with transport theory avoid errors associated with spatial homogenization commonly used in diffusion methods in reactor core simulators

  13. Optimal Strategy for Economic Operation of Electric Bus Battery Swapping Station%快换式电动公交充电站经济运行优化策略

    Institute of Scientific and Technical Information of China (English)

    杨少兵; 吴命利; 姜久春; 赵伟

    2014-01-01

    备用电池数量、充电时长是影响换电站换电能力的主要因素。基于车辆进站流量分析,提出了描述换电需求和电池充电产量的函数,进一步分析了两者之间的关系,提出了针对电价峰段的充电控制方法。以北京奥运电动公交充电站为例阐述了经济运行优化策略的应用步骤,并编写了计算机仿真程序进行验证。结果表明:所提经济运行优化策略在满足任意时刻换电需求的条件下可显著降低电价峰段用电量,较大幅度地减少换电站的电费支出。同时,该策略所包含的算法及边界条件非常清晰,容易嵌入充电管理系统实现换电站的经济运行优化控制。%The reserved battery number and the charging duration are main factors to affect the energy supply capacity of electric bus battery swapping station. Based on the analysis of vehicle flow, two formulas are presented to describe required battery amount and charged battery amount respectively. Moreover, with analyzing the relation between the two formulas, a charging control method for the peak period is provided. According to the field test data and statistical results of the electric bus swapping station for 2008 Beijing Olympic Games, the procedures of optimal strategy for economic operation have been given. Then a computer simulation program is prepared to verify the strategy. Simulation results show that the proposed strategy can reduce power consumption of peak periods and electricity costs markedly while it meets the condition at swapping demand. In addition, the algorithm and boundary conditions are very clear, and it is easy to be embedded into a charging management system to implement economic optimization for bus battery swapping stations.

  14. An Optimization Framework for Dynamic Hybrid Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wenbo Du; Humberto E Garcia; Christiaan J.J. Paredis

    2014-03-01

    A computational framework for the efficient analysis and optimization of dynamic hybrid energy systems (HES) is developed. A microgrid system with multiple inputs and multiple outputs (MIMO) is modeled using the Modelica language in the Dymola environment. The optimization loop is implemented in MATLAB, with the FMI Toolbox serving as the interface between the computational platforms. Two characteristic optimization problems are selected to demonstrate the methodology and gain insight into the system performance. The first is an unconstrained optimization problem that optimizes the dynamic properties of the battery, reactor and generator to minimize variability in the HES. The second problem takes operating and capital costs into consideration by imposing linear and nonlinear constraints on the design variables. The preliminary optimization results obtained in this study provide an essential step towards the development of a comprehensive framework for designing HES.

  15. Battery-Aware Scheduling of Mixed Criticality Systems

    DEFF Research Database (Denmark)

    Wognsen, Erik Ramsgaard; Hansen, Rene Rydhof; Larsen, Kim Guldstrand

    2014-01-01

    Wireless systems such as satellites and sensor networks are often battery-powered. To operate optimally they must therefore take the performance properties of real batteries into account. Additionally, these systems, and therefore their batteries, are often exposed to loads with uncertain timings...

  16. A class-based search for the in-core fuel management optimization of a pressurized water reactor

    International Nuclear Information System (INIS)

    The In-Core Fuel Management Optimization (ICFMO) is a prominent problem in nuclear engineering, with high complexity and studied for more than 40 years. Besides manual optimization and knowledge-based methods, optimization metaheuristics such as Genetic Algorithms, Ant Colony Optimization and Particle Swarm Optimization have yielded outstanding results for the ICFMO. In the present article, the Class-Based Search (CBS) is presented for application to the ICFMO. It is a novel metaheuristic approach that performs the search based on the main nuclear characteristics of the fuel assemblies, such as reactivity. The CBS is then compared to the one of the state-of-art algorithms applied to the ICFMO, the Particle Swarm Optimization. Experiments were performed for the optimization of Angra 1 Nuclear Power Plant, located at the Southeast of Brazil. The CBS presented noticeable performance, providing Loading Patterns that yield a higher average of Effective Full Power Days in the simulation of Angra 1 NPP operation, according to our methodology.

  17. A class-based search for the in-core fuel management optimization of a pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga de Moura Meneses, Anderson, E-mail: ameneses@lmp.ufrj.b [Federal University of Rio de Janeiro, COPPE, Nuclear Engineering Program, CP 68509, CEP 21.941-972, Rio de Janeiro, RJ (Brazil); Rancoita, Paola [IDSIA (Dalle Molle Institute for Artificial Intelligence), Galleria 2, 6982 Manno-Lugano, TI (Switzerland); Mathematics Department, Universita degli Studi di Milano (Italy); Schirru, Roberto [Federal University of Rio de Janeiro, COPPE, Nuclear Engineering Program, CP 68509, CEP 21.941-972, Rio de Janeiro, RJ (Brazil); Gambardella, Luca Maria [IDSIA (Dalle Molle Institute for Artificial Intelligence), Galleria 2, 6982 Manno-Lugano, TI (Switzerland)

    2010-11-15

    The In-Core Fuel Management Optimization (ICFMO) is a prominent problem in nuclear engineering, with high complexity and studied for more than 40 years. Besides manual optimization and knowledge-based methods, optimization metaheuristics such as Genetic Algorithms, Ant Colony Optimization and Particle Swarm Optimization have yielded outstanding results for the ICFMO. In the present article, the Class-Based Search (CBS) is presented for application to the ICFMO. It is a novel metaheuristic approach that performs the search based on the main nuclear characteristics of the fuel assemblies, such as reactivity. The CBS is then compared to the one of the state-of-art algorithms applied to the ICFMO, the Particle Swarm Optimization. Experiments were performed for the optimization of Angra 1 Nuclear Power Plant, located at the Southeast of Brazil. The CBS presented noticeable performance, providing Loading Patterns that yield a higher average of Effective Full Power Days in the simulation of Angra 1 NPP operation, according to our methodology.

  18. Present status of reactor physics in the United States and Japan-III. 1. Recent Activities of Loading Pattern Optimization Research in Japan

    International Nuclear Information System (INIS)

    Because of recent enhancements of optimization algorithms and great improvements in computer hardware, loading pattern (LP) optimization methods are being used as practical design tools both in the pressurized water reactor (PWR) and boiling water reactor (BWR) industries. LP optimization methods are mainly used for the following in-core fuel management activities in Japan: 1. minimization of fuel cycle costs; 2. evaluation of various in-core fuel management scenarios; 3. estimation of the number of feed assemblies needed during several successive cycles for fuel ordering; 4. evaluation of fuel bids. Although engineers can perform these analyses, the major motivations to utilize LP optimization methods are the reduction of manpower and the establishment of engineer-independent LP quality. These are important in today's in-core fuel management tasks. In the following sections, activities related to LP optimization research in Japan are briefly described. The major activity of PWR LP optimization research in Japan is development of the INSIGHT system. The INSIGHT system is an integrated scoping analysis tool for PWRs developed by Nuclear Fuel Industries (NFI). The INSIGHT system is a graphical user interface (GUI)-based interactive design tool that includes LP optimization, automated multicycle analysis, an interactive LP design, core follow, an integrated database, and some auxiliary functions. The INSIGHT system was mainly written in the C++ language and consists of ∼400 000 lines of source code. The GALLOP code is the LP optimization module of the INSIGHT system. An automated multicycle analysis is performed by the MCA code in INSIGHT. The MCA code performs a fuel and burnable poison (BP) inventory search by automatically invoking the GALLOP code, which makes LPs. The MCA code can deal with various constraints that have appeared in practical in-core fuel management, e.g., limitations of fuel/BP stock, forced fuel loading/discharge, limitations of core safety

  19. PRODUCTION OF MEDIUM-CHAIN ACYLGLYCEROLS BY LIPASE ESTERIFICATION IN PACKED BED REACTOR: PROCESS OPTIMIZATION BY RESPONSE SURFACE METHODOLOGY

    OpenAIRE

    ZANARIAH MOHD DOM; LING TAU CHUAN; ROZITA YUSOFF

    2014-01-01

    Medium-chain acylglycerols (or glycerides) are formed of mono-, di- and triacylglycerol classes. In this study, an alternative method to produce MCA from esterifying palm oil fatty acid distillate (PFAD) with the presence of oil palm mesocarp lipase (OPML) which is a plant-sourced lipase and PFAD is also cheap by-product is developed in a packed bed reactor. The production of medium-chain acylglycerols (MCA) by lipase-catalysed esterification of palm oil fatty acid distillate with glycerol ar...

  20. Preparation of a Rechargeable Battery Using Waste Protein from the Fish Scales

    International Nuclear Information System (INIS)

    The electrochemical redox reactions of the oxytocin and fish scale protein which are mainly collagen were exploited for the preparation of a rechargeable protein battery named as fish scale battery. This battery was found to depend upon the concentration of oxidizing and reducing agents, voltage of the charger and the time for charging. Some of these parameters were optimized using a single cell of this battery and some others were optimized by using five cell battery. The five cell protein battery gives a maximum and stable voltage of 8500 millivolt. The way of charging and theoretical aspects of the battery is also discussed in this communication. (author)

  1. Optimal nodulation schemas of WWer-1000 reactor pressure vessel for the coupled code ATHLET-BIPR8KN

    International Nuclear Information System (INIS)

    The coupled code system ATHLET-BIPR8KN is being developed to perform realistic simulation of three-dimensional neutron kinetics and thermal-hydraulic processes in WWER reactors. The detailed description of the flow mixing in the all reactor vessel is of great importance for the correct modeling and simulation of many NPP transients. As contribution to the validation of the system code ATHLET-BIPR8KN for asymmetric core inlet conditions, the CEA-NEA/OECD WWER-1000 Coolant Transient Benchmark (W1000CT) - vessel mixing problems are analyzed. Results are presented for Exercise 1 of the Phase 2 of the Benchmark obtained with the system code ATHLET-BIPR8KN, supplemented by sensible studies done on the variation of the number of the thermo-hydraulic channels with cross flows (CF) in down comers and bottom plenums under the core with CF and with 163 (1:1 mapping schema) parallel thermal-hydraulic channels (PTHC) without of CF in the core and 48 PTHC without of CF for the core bypass. The transient is a simultaneous isolation of one steam generator from the steam line and the feed water supply at low power level. It causes a temperature rise in the affected loop and leads to a non-uniform temperature distribution at core inlet. The results of the simulation are compared with experimental data from NPP Kozloduy Unit 6 collected during the plant-commissioning phase (Authors)

  2. Optimization of a partially non-magnetic primary radiation shielding for the triple-axis spectrometer PANDA at the Munich high-flux reactor FRM-II

    CERN Document Server

    Pyka, N M; Rogov, A

    2002-01-01

    Monte Carlo simulations have been used to optimize the monochromator shielding of the polarized cold-neutron triple-axis spectrometer PANDA at the Munich high-flux reactor FRM-II. By using the Monte Carlo program MCNP-4B, the density of the total spectrum of incoming neutrons and gamma radiation from the beam tube SR-2 has been determined during the three-dimensional diffusion process in different types of heavy concrete and other absorbing material. Special attention has been paid to build a compact and highly efficient shielding, partially non-magnetic, with a total biological radiation dose of less than 10 mu Sv/h at its outsides. Especially considered was the construction of an albedo reducer, which serves to reduce the background in the experiment outside the shielding. (orig.)

  3. Memel's Batteries

    Directory of Open Access Journals (Sweden)

    Alexander F. Mitrofanov

    2015-12-01

    Full Text Available The article describes the history and equipment of the coastal and antiaircraft artillery batteries of German Navy (Kriegsmarine constructed in Memel area before and during the World War. There is given the brief description of the Soviet Navy stationed in the area in the postwar years.

  4. Optimization study and neutronic and thermal-hydraulic design calculations of a 75 KWTH aqueous homogeneous reactor for medical isotopes production

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Daniel Milian; Lorenzo, Daniel E. Milian; Garcia, Lorena P. Rodriguez; Llanes, Jesus Salomon; Hernandez, Carlos R. Garcia, E-mail: dperez@instec.cu, E-mail: dmilian@instec.cu, E-mail: lorenapilar@instec.cu, E-mail: cgh@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Lira, Carlos A. Brayner de Oliveira, E-mail: cabol@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife (Brazil); Rodriguez, Manuel Cadavid, E-mail: mcadavid2001@yahoo.com [Tecnologia Nuclear Medica Spa, TNM (Chile)

    2015-07-01

    {sup 99m}Tc is the most common radioisotope used in nuclear medicine. It is a very useful radioisotope, which is used in about 30-40 million procedures worldwide every year. Medical diagnostic imaging techniques using {sup 99m}Tc represent approximately 80% of all nuclear medicine procedures. Although {sup 99m}Tc can be produced directly on a cyclotron or other type of particle accelerator, currently is almost exclusively produced from the beta-decay of its 66-h parent {sup 99}Mo. {sup 99}Mo production system in an Aqueous Homogeneous Reactor (AHR) is potentially advantageous because of its low cost, small critical mass, inherent passive safety, and simplified fuel handling, processing and purification characteristics. In this paper, an AHR conceptual design using Low Enriched Uranium (LEU) is studied and optimized for the production of {sup 99}Mo. Aspects related with the neutronic behavior such as optimal reflector thickness, critical height, medical isotopes production and the reactivity feedback introduced in the solution by the volumetric expansion of the fuel solution due to thermal expansion of the fuel solution and the void volume generated by radiolytic gas bubbles were evaluated. Thermal-hydraulics studies were carried out in order to show that sufficient cooling capacity exists to prevent fuel overheating. The neutronic and thermal-hydraulics calculations have been performed with the MCNPX computational code and the version 14 of ANSYS CFX respectively. The neutronic calculations demonstrated that the reactor is able to produce 370 six-day curies of {sup 99}Mo in 5 days operation cycles and the CFD simulation demonstrated that the heat removal systems provide sufficient cooling capacity to prevent fuel overheating, the maximum temperature reached by the fuel (89.29 deg C) was smaller to the allowable temperature limit (90 deg C). (author)

  5. 基于等可信容量的风光储电源优化配置方法%Optimal Configuration of Distributed Generation System Containing Wind PV Battery Power Sources Based on Equivalent Credible Capacity Theory

    Institute of Scientific and Technical Information of China (English)

    何俊; 邓长虹; 徐秋实; 刘翠琳; 潘华

    2013-01-01

    含风光储的发电系统容量优化问题中,所要考虑的不确定性不仅包括常规机组的随机停运,还包括风速和光照强度的随机变化对机组出力造成的波动。提出一种基于等可信容量的风光储容量优化配置方法,综合计及自然资源的随机波动和常规机组的随机停运影响,按照满足电力平衡的需求确定所需风光储发电系统的整体可信容量以及常规机组容量,通过蒙特卡罗仿真计算得到等可信容量所需的风光储机组组合,根据风光储容量优化配置模型,从上述组合集合中选出使全生命周期总投资成本最小的风、光、储容量配置。采用加入了风电和光伏发电后的某实际海岛算例验证了该方法的正确性和有效性。%In the capacity optimization of coordination power generation system containing wind farm, photovoltaic (PV) generation and battery hybrid system, the uncertainty factors to be considered include not only the random outage of conventional generation units, but also unit output fluctuation due to random variation of wind speed and illumination intensity. Based on equivalent credible capacity theory an optimal configuration method of wind PV battery hybrid generation system, in which the impacts due to random fluctuation of natural resources and random outage of conventional generation units are synthetically taken into account, is proposed and according to the demand on satisfying electric power balance the needed overall capacity of wind/PV/battery hybrid generation system and the capacity of conventional generation units are determined;then through Monte Carlo simulation the wind/PV/battery hybrid unit combinations needed by equivalent credible capacity are calculated; and then according to the optimal configuration model of wind/PV/battery capacity, the wind PV battery capacity configuration, which makes the total investment cost in full lifecycle minimized, is selected from

  6. Batteries: Overview of Battery Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Doeff, Marca M

    2010-07-12

    The very high theoretical capacity of lithium (3829 mAh/g) provided a compelling rationale from the 1970's onward for development of rechargeable batteries employing the elemental metal as an anode. The realization that some transition metal compounds undergo reductive lithium intercalation reactions reversibly allowed use of these materials as cathodes in these devices, most notably, TiS{sub 2}. Another intercalation compound, LiCoO{sub 2}, was described shortly thereafter but, because it was produced in the discharged state, was not considered to be of interest by battery companies at the time. Due to difficulties with the rechargeability of lithium and related safety concerns, however, alternative anodes were sought. The graphite intercalation compound (GIC) LiC{sub 6} was considered an attractive candidate but the high reactivity with commonly used electrolytic solutions containing organic solvents was recognized as a significant impediment to its use. The development of electrolytes that allowed the formation of a solid electrolyte interface (SEI) on surfaces of the carbon particles was a breakthrough that enabled commercialization of Li-ion batteries. In 1990, Sony announced the first commercial batteries based on a dual Li ion intercalation system. These devices are assembled in the discharged state, so that it is convenient to employ a prelithiated cathode such as LiCoO{sub 2} with the commonly used graphite anode. After charging, the batteries are ready to power devices. The practical realization of high energy density Li-ion batteries revolutionized the portable electronics industry, as evidenced by the widespread market penetration of mobile phones, laptop computers, digital music players, and other lightweight devices since the early 1990s. In 2009, worldwide sales of Li-ion batteries for these applications alone were US$ 7 billion. Furthermore, their performance characteristics (Figure 1) make them attractive for traction applications such as

  7. Batteries: Overview of Battery Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Doeff, Marca M

    2010-07-12

    The very high theoretical capacity of lithium (3829 mAh/g) provided a compelling rationale from the 1970's onward for development of rechargeable batteries employing the elemental metal as an anode. The realization that some transition metal compounds undergo reductive lithium intercalation reactions reversibly allowed use of these materials as cathodes in these devices, most notably, TiS{sub 2}. Another intercalation compound, LiCoO{sub 2}, was described shortly thereafter but, because it was produced in the discharged state, was not considered to be of interest by battery companies at the time. Due to difficulties with the rechargeability of lithium and related safety concerns, however, alternative anodes were sought. The graphite intercalation compound (GIC) LiC{sub 6} was considered an attractive candidate but the high reactivity with commonly used electrolytic solutions containing organic solvents was recognized as a significant impediment to its use. The development of electrolytes that allowed the formation of a solid electrolyte interface (SEI) on surfaces of the carbon particles was a breakthrough that enabled commercialization of Li-ion batteries. In 1990, Sony announced the first commercial batteries based on a dual Li ion intercalation system. These devices are assembled in the discharged state, so that it is convenient to employ a prelithiated cathode such as LiCoO{sub 2} with the commonly used graphite anode. After charging, the batteries are ready to power devices. The practical realization of high energy density Li-ion batteries revolutionized the portable electronics industry, as evidenced by the widespread market penetration of mobile phones, laptop computers, digital music players, and other lightweight devices since the early 1990s. In 2009, worldwide sales of Li-ion batteries for these applications alone were US$ 7 billion. Furthermore, their performance characteristics (Figure 1) make them attractive for traction applications such as

  8. Production of specifically structured lipids by enzymatic interesterification in a pilot enzyme bed reactor: process optimization by response surface methodology

    DEFF Research Database (Denmark)

    Xu, Xuebing; Mu, Huiling; Høy, Carl-Erik;

    1999-01-01

    °C; substrate ratio, 5.5; and water content, 0.1%. The production of diacylglycerols was not well correlated with any of the parameters and the yield generally decreased with the experimental sequence. This was due to the stoichiometric water in the substrate mixture in the packed enzyme bed being......Pilot production of specifically structured lipids by Lipozyme IM-catalyzed interesterification was carried out in a continuous enzyme bed reactor without the use of solvent. Medium chain triacylglycerols and oleic acid were used as model substrates. Response surface methodology was applied...... was not identical for the sequential experiments in the same enzyme bed due to the deactivation of the Lipozyme IM. Therefore, the results were normalized based on enzyme deactivation models. Well-fitting quadratic models were obtained after normalizing the data for the incorporation of oleic acid...

  9. Optimization of the biodegradation of phenol in a RDS; Optimizacion de la biodegradacion de fenol en un reactor discontinuo secuencial

    Energy Technology Data Exchange (ETDEWEB)

    Rancano, A.

    2007-07-01

    In this work the ideal conditions have been studied for the operation of a RDS to take to end the biological degradation of phenol. the results have shown that to minimize the time needed in the degradation the water volume that has to get in every cycle of operation is a function of the concentration of phenol in the nourishment, diminishing this volume on having increased the concentration, to avoid this way the presence of high concentrations of phenol inside the biological reactor, which would provoke low speeds of degradation. If it occurs in the ideal conditions of operation, the time needed to take to end the degradation of the phenol increases linearly with the concentration of phenol in the nourishment, whereas if in every cycle of operation a fixed volume of water is treated, the time needed increases much more rapidly with the concentration of phenol. (Author) 14 refs.

  10. 包含蓄电池储能和负荷转移的微网经济运行优化%Economic operation optimization for micro-grid with battery storage and load transfer

    Institute of Scientific and Technical Information of China (English)

    尹晓海; 任玉梁; 杜欣慧

    2015-01-01

    提出一种同时包含蓄电池储能和负荷转移的微网经济运行优化方法. 该方法将全天24 h划分为谷平峰3种时段,在谷平时段设计蓄电池充电补偿函数、放电罚函数,峰时段设计蓄电池充、放电罚函数;同时将部分负荷从峰时段转移到谷平时段. 通过引导微网在不同时段合理对蓄电池进行充放电、向电网进行购售电,不仅减少了微网经济运行费用,而且对电网起到"移峰填谷"作用. 利用LINGO优化软件对混合整数、非线性组合模型进行求解. 结果表明,微网全天经济运行费用减少了13.4%,具有较好的经济效益.%A method of economic operation optimization for micro-grid with battery storage and load transfer is pro-posed, which divides the whole day into valley period, normal period and peak period, and designs battery charge compensation function and discharge penalty function at valley and normal periods and designs charge compensation and penalty function at peak period.Micro-grid is reasonably guided to charge and discharge battery, purchase and sell electricity to the main grid at different periods, which not only reduces the micro-grid economic operation cost, but also helps the"peak clipping and valley filling" of main grid.LINGO optimizing software is applied to solve the mixed-integer and nonlinear models.The result indicates with the battery charge and discharge management and load transfer, micro-grid economic operation cost throughout the day reduces by 13.4%,which has good economic benefit.

  11. Optimization of micro-aeration intensity in acidogenic reactor of a two-phase anaerobic digester treating food waste.

    Science.gov (United States)

    Xu, Suyun; Selvam, Ammaiyappan; Wong, Jonathan W C

    2014-02-01

    Micro-aeration is known to promote the activities of hydrolytic exo-enzymes and used as a strategy to improve the hydrolysis of particulate substrate. The effect of different micro-aeration rates, 0, 129, 258, and 387 L-air/kg TS/d (denoted as LBR-AN, LBR-6h, LBR-3h and LBR-2h, respectively) on the solubilization of food waste was evaluated at 35°C in four leach bed reactors (LBR) coupled with methanogenic upflow anaerobic sludge blanket (UASB) reactor. Results indicate that the intensity of micro-aeration influenced the hydrolysis and methane yield. Adequate micro-aeration intensity in LBR-3h and LBR-2h significantly enhanced the carbohydrate and protein hydrolysis by 21-27% and 38-64% respectively. Due to the accelerated acidogenesis, more than 3-fold of acetic acid and butyric acid were produced in LBR-3h as compared to the anaerobic treatment LBR-AN resulting in the maximum methane yield of 0.27 L CH4/g VS(added) in the UASB. The performance of LBR-6h with inadequate aeration was similar to that of LBR-AN with a comparable hydrolysis degree. Nevertheless, higher aeration intensity in LBR-2h was also unfavorable for methane yield due to significant biomass generation and CO2 respiration of up to 18.5% and 32.8% of the total soluble hydrolysate, respectively. To conclude, appropriate micro-aeration rate can promote the hydrolysis of solid organic waste and methane yield without undesirable carbon loss and an aeration intensity of 258 L-air/kg TS/d is recommended for acidogenic LBR treating food waste.

  12. Functional materials for rechargeable batteries.

    Science.gov (United States)

    Cheng, Fangyi; Liang, Jing; Tao, Zhanliang; Chen, Jun

    2011-04-19

    There is an ever-growing demand for rechargeable batteries with reversible and efficient electrochemical energy storage and conversion. Rechargeable batteries cover applications in many fields, which include portable electronic consumer devices, electric vehicles, and large-scale electricity storage in smart or intelligent grids. The performance of rechargeable batteries depends essentially on the thermodynamics and kinetics of the electrochemical reactions involved in the components (i.e., the anode, cathode, electrolyte, and separator) of the cells. During the past decade, extensive efforts have been dedicated to developing advanced batteries with large capacity, high energy and power density, high safety, long cycle life, fast response, and low cost. Here, recent progress in functional materials applied in the currently prevailing rechargeable lithium-ion, nickel-metal hydride, lead acid, vanadium redox flow, and sodium-sulfur batteries is reviewed. The focus is on research activities toward the ionic, atomic, or molecular diffusion and transport; electron transfer; surface/interface structure optimization; the regulation of the electrochemical reactions; and the key materials and devices for rechargeable batteries. PMID:21394791

  13. Optimal Conditions for Fast Charging and Long Cycling Stability of Silicon Microwire Anodes for Lithium Ion Batteries, and Comparison with the Performance of Other Si Anode Concepts

    OpenAIRE

    Enrique Quiroga-González; Jürgen Carstensen; Helmut Föll

    2013-01-01

    Cycling tests under various conditions have been performed for lithium ion battery anodes made from free-standing silicon microwires embedded at one end in a copper current collector. Optimum charging/discharging conditions have been found for which the anode shows negligible fading (< 0.001%) over 80 cycles; an outstanding result for this kind of anodes. Several performance parameters of the anode have been compared to the ones of other Si anode concepts, showing that especially the capacity...

  14. Batteries for Electric Vehicles

    Science.gov (United States)

    Conover, R. A.

    1985-01-01

    Report summarizes results of test on "near-term" electrochemical batteries - (batteries approaching commercial production). Nickel/iron, nickel/zinc, and advanced lead/acid batteries included in tests and compared with conventional lead/acid batteries. Batteries operated in electric vehicles at constant speed and repetitive schedule of accerlerating, coasting, and braking.

  15. Battery Safety Basics

    Science.gov (United States)

    Roy, Ken

    2010-01-01

    Batteries commonly used in flashlights and other household devices produce hydrogen gas as a product of zinc electrode corrosion. The amount of gas produced is affected by the batteries' design and charge rate. Dangerous levels of hydrogen gas can be released if battery types are mixed, batteries are damaged, batteries are of different ages, or…

  16. Application of the Particle Swarm Optimization (PSO) technique to the thermal-hydraulics project of a PWR reactor core in reduced scale

    International Nuclear Information System (INIS)

    The reduced scale models design have been employed by engineers from several different industries fields such as offshore, spatial, oil extraction, nuclear industries and others. Reduced scale models are used in experiments because they are economically attractive than its own prototype (real scale) because in many cases they are cheaper than a real scale one and most of time they are also easier to build providing a way to lead the real scale design allowing indirect investigations and analysis to the real scale system (prototype). A reduced scale model (or experiment) must be able to represent all physical phenomena that occurs and further will do in the real scale one under operational conditions, e.g., in this case the reduced scale model is called similar. There are some different methods to design a reduced scale model and from those two are basic: the empiric method based on the expert's skill to determine which physical measures are relevant to the desired model; and the differential equation method that is based on a mathematical description of the prototype (real scale system) to model. Applying a mathematical technique to the differential equation that describes the prototype then highlighting the relevant physical measures so the reduced scale model design problem may be treated as an optimization problem. Many optimization techniques as Genetic Algorithm (GA), for example, have been developed to solve this class of problems and have also been applied to the reduced scale model design problem as well. In this work, Particle Swarm Optimization (PSO) technique is investigated as an alternative optimization tool for such problem. In this investigation a computational approach, based on particle swarm optimization technique (PSO), is used to perform a reduced scale two loop Pressurized Water Reactor (PWR) core, considering 100% of nominal power operation on a forced flow cooling circulation and non-accidental operating conditions. A performance comparison

  17. Battery Sizing for Plug-in Hybrid Electric Vehicles in Beijing: A TCO Model Based Analysis

    Directory of Open Access Journals (Sweden)

    Cong Hou

    2014-08-01

    Full Text Available This paper proposes a total cost of ownership (TCO model for battery sizing of plug-in hybrid electric vehicles (PHEVs. The proposed systematic TCO model innovatively integrates the Beijing driving database and optimal PHEV energy management strategies developed earlier. The TCO, including battery, fuel, electricity, and salvage costs, is calculated in yearly cash flows. The salvage cost, based on battery degradation model, is proposed for the first time. The results show that the optimal battery size for PHEVs in Beijing is 6–8 kWh. Several additional scenarios are also analyzed: (1 10% increase in battery price or discount rate leads to an optimal battery size of 6 kWh, and 10% increase in fuel price shifts the optimal battery size to 8 kWh; (2 the longer and more dispersive daily range distribution in the U.S. increases the optimal battery size to 14 kWh; (3 the subsidy in China results in an optimal battery size of 13 kWh, while that in the U.S. results in 17 kWh, and a fuel savings rate based subsidy policy is innovatively proposed; (4 the optimal battery size with Li4Ti5O12 batteries is 2 kWh, but the TCO of Li4Ti5O12 batteries is higher than that of LiFePO4 batteries.

  18. Design of an Adaptive PID Neural Controller for Continuous Stirred Tank Reactor based on Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Khulood A. Dagher

    2013-12-01

    Full Text Available A particle swarm optimization algorithm and neural network like self-tuning PID controller for CSTR system is presented. The scheme of the discrete-time PID control structure is based on neural network and tuned the parameters of the PID controller by using a particle swarm optimization PSO technique as a simple and fast training algorithm. The proposed method has advantage that it is not necessary to use a combined structure of identification and decision because it used PSO. Simulation results show the effectiveness of the proposed adaptive PID neural control algorithm in terms of minimum tracking error and smoothness control signal obtained for non-linear dynamical CSTR system.

  19. Optimization of the preconcentration system of cadmium with 1(2-thiazolylazo)-p-cresol using a knotted reactor and flame atomic absorption spectrometric detection

    International Nuclear Information System (INIS)

    The present paper proposes an on-line preconcentration procedure for cadmium determination in drinking water samples. It is based on the precipitation of cadmium(II) ions on a knotted reactor (KR) using 1(2-thiazolylazo)-p-cresol (TAC) as complexing reagent. The optimization step was performed using a full factorial design involving the variables: pH, eluent concentration (nitric acid) and TAC concentration. The results of this experiment demonstrated that these variables at chosen levels are not statistically significant. Under optimized experimental established conditions, analytical parameters for the preconcentration method were: a detection limit of 40.0 ng/l, precision as relative standard deviation (RSD) of 1.2 and 1.0%, for cadmium concentration of 2.5 and 20.0 μg/l, respectively. The preconcentration factor considering the slopes of the analytical curves with and without preconcentration is 23 for a sample volume of 10 ml. This system shows a sampling frequency of 25 h-1. In order to check the accuracy, the standard reference material, NIST SRM 1643d trace elements in water was analyzed. A comparison, using t-test demonstrates that there is not significant difference among the achieved results with proposed method and the certified values. The addition/recovery experiments in the samples analyzed demonstrated the accuracy and applicability of the system developed for cadmium determination in water samples

  20. Optimization of micro-aeration intensity in acidogenic reactor of a two-phase anaerobic digester treating food waste

    International Nuclear Information System (INIS)

    Highlights: • Effect of micro-aeration on acidogenesis and hydrolysis of food waste was investigated. • Micro-aeration at 258 L-air/kg TS/d increased the VFAs production 3-fold. • High aeration leads to loss of substrate through microbial biomass and respiration. • Optimum aeration increased methane recovery while high aeration intensity reduced methane yield. - Abstract: Micro-aeration is known to promote the activities of hydrolytic exo-enzymes and used as a strategy to improve the hydrolysis of particulate substrate. The effect of different micro-aeration rates, 0, 129, 258, and 387 L-air/kg TS/d (denoted as LBR-AN, LBR-6h, LBR-3h and LBR-2h, respectively) on the solubilization of food waste was evaluated at 35 °C in four leach bed reactors (LBR) coupled with methanogenic upflow anaerobic sludge blanket (UASB) reactor. Results indicate that the intensity of micro-aeration influenced the hydrolysis and methane yield. Adequate micro-aeration intensity in LBR-3h and LBR-2h significantly enhanced the carbohydrate and protein hydrolysis by 21–27% and 38–64% respectively. Due to the accelerated acidogenesis, more than 3-fold of acetic acid and butyric acid were produced in LBR-3h as compared to the anaerobic treatment LBR-AN resulting in the maximum methane yield of 0.27 L CH4/g VSadded in the UASB. The performance of LBR-6h with inadequate aeration was similar to that of LBR-AN with a comparable hydrolysis degree. Nevertheless, higher aeration intensity in LBR-2h was also unfavorable for methane yield due to significant biomass generation and CO2 respiration of up to 18.5% and 32.8% of the total soluble hydrolysate, respectively. To conclude, appropriate micro-aeration rate can promote the hydrolysis of solid organic waste and methane yield without undesirable carbon loss and an aeration intensity of 258 L-air/kg TS/d is recommended for acidogenic LBR treating food waste

  1. Design of a weapons-grade plutonium assembly for optimal burnup in a standard pressurized water reactor

    Science.gov (United States)

    Alonso-Vargas, Gustavo

    We created a new MOX fuel assembly design that can be used in standard Westinghouse pressurized water reactors (PWR) to maximize the plutonium throughput while introducing the lowest perturbation possible to the control and safety systems of the reactor. Our assembly design, which is called MIX-33, appears to be a good option for the disposition of weapons-grade plutonium (WG-Pu), increasing the plutonium disposition rate by 8% compared to a previous Westinghouse design. It is based in two novel ideas: the use of both uranium and plutonium fuel pins in the same assembly, and the increase of the moderation ratio of the assembly. We replaced 8 fuel pins by water holes to increase the moderation ratio. We can transition smoothly from a full LEU core to a full MIX-33 core meeting the operational and safety regulations of a standard PWR. Given a MOX supply interruption scenario we can transition smoothly to full LEU meeting the safety regulations and using standard LEU assemblies with uniform enriched pin-wise distribution. If the MOX supply is interrupted for only one cycle, we are able to transition back to full MIX-33 core. However, in this case we probably need to de-rate the power by a few percent for a few weeks at the beginning of the cycle (BOC) to accommodate high peaking. For comparison we created another assembly design without extra water holes, which we called "MIX-25". It behaves in all the conditions analyzed in a similar way to the MIX-33 but it does present minor control problems. These can be solved by making small modifications to the control and safety systems, namely by enriching the boron-10 content of some boron absorbers. Thus, the addition of water holes replacing fuel pins helps to improve the MIX-33 performance and eliminate the difficulties seen in the MIX-25 design. We also performed a benchmarking analysis to test the code CASMO-3 to analyze WG-Pu assemblies, using the code MCNP-4A to compare. We found good agreement between CASMO-3 and

  2. A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Jorge [Univ. of Utah, Salt Lake City, UT (United States)

    2013-12-01

    The goal of this study presented is to determine the best available non-destructive technique necessary to collect validation data as well as to determine burn-up and cooling time of the fuel elements onsite at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads3 to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements non-destructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed was used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however in order to enhance the quality of the spectra collected using this scintillator a deconvolution method was developed. Following the development of the deconvolution method

  3. Optimization of micro-aeration intensity in acidogenic reactor of a two-phase anaerobic digester treating food waste

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Suyun [Department of Environmental and Low-Carbon Science, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai (China); Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region (Hong Kong); Selvam, Ammaiyappan [Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region (Hong Kong); Wong, Jonathan W.C., E-mail: jwcwong@hkbu.edu.hk [Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region (Hong Kong)

    2014-02-15

    Highlights: • Effect of micro-aeration on acidogenesis and hydrolysis of food waste was investigated. • Micro-aeration at 258 L-air/kg TS/d increased the VFAs production 3-fold. • High aeration leads to loss of substrate through microbial biomass and respiration. • Optimum aeration increased methane recovery while high aeration intensity reduced methane yield. - Abstract: Micro-aeration is known to promote the activities of hydrolytic exo-enzymes and used as a strategy to improve the hydrolysis of particulate substrate. The effect of different micro-aeration rates, 0, 129, 258, and 387 L-air/kg TS/d (denoted as LBR-AN, LBR-6h, LBR-3h and LBR-2h, respectively) on the solubilization of food waste was evaluated at 35 °C in four leach bed reactors (LBR) coupled with methanogenic upflow anaerobic sludge blanket (UASB) reactor. Results indicate that the intensity of micro-aeration influenced the hydrolysis and methane yield. Adequate micro-aeration intensity in LBR-3h and LBR-2h significantly enhanced the carbohydrate and protein hydrolysis by 21–27% and 38–64% respectively. Due to the accelerated acidogenesis, more than 3-fold of acetic acid and butyric acid were produced in LBR-3h as compared to the anaerobic treatment LBR-AN resulting in the maximum methane yield of 0.27 L CH{sub 4}/g VS{sub added} in the UASB. The performance of LBR-6h with inadequate aeration was similar to that of LBR-AN with a comparable hydrolysis degree. Nevertheless, higher aeration intensity in LBR-2h was also unfavorable for methane yield due to significant biomass generation and CO{sub 2} respiration of up to 18.5% and 32.8% of the total soluble hydrolysate, respectively. To conclude, appropriate micro-aeration rate can promote the hydrolysis of solid organic waste and methane yield without undesirable carbon loss and an aeration intensity of 258 L-air/kg TS/d is recommended for acidogenic LBR treating food waste.

  4. Removal of pharmaceuticals from wastewater by electrochemical oxidation using cylindrical flow reactor and optimization of treatment conditions.

    Science.gov (United States)

    Babu, B Ramesh; Venkatesan, P; Kanimozhi, R; Basha, C Ahmed

    2009-08-01

    This paper examines the use of electrooxidation for treatment of wastewater obtained from a pharmaceutical industry. The wastewater primarily contained Gentamicin and Dexamethasone. With NaCl as supporting electrolyte, the effluent was treated in a cylindrical flow reactor in continuous (single pass) mode under various current densities (2-5 A/dm2) and flow rates (10-40 L/h). By cyclic voltammetric (CV) analysis, the optimum condition for maximum redox reaction was determined. The efficiency of chemical oxygen demand (COD) reduction and power consumption were studied for different operating conditions. From the results it was observed that maximum COD reduction of about 85.56% was obtained at a flow rate of 10 L/h with an applied current density of 4 A/dm2. FT-IR spectra studies showed that during electrooxidation, the intensities of characteristic functional groups such as N-H, O-H were reduced and some new peaks also started to appear. Probable theory, reaction mechanism and modeling were proposed for the oxidation of pharmaceutical effluent. The experimental results demonstrated that electrooxidation treatment was very effective and capable of elevating the quality of treated wastewater to the reuse standard prescribed for pharmaceutical industries.

  5. Security of supply for fission medical radio-isotopes based on optimal use of the test reactor network

    International Nuclear Information System (INIS)

    Nuclear Medicine relies to a large extend (80 % of the procedures) on radioisotopes produced by fission of uranium, on Mo99 /Tc99m for 28 million diagnoses made annually all over the world for tracking diseases in cancerology, cardiology, neurology ... and on I131 and Y90 for 3 million therapy procedures. The only four main producers (95 % of the world demand) are relying on 5 aging test reactors for irradiating HEU targets to be processed for extracting these short life isotopes before their conditioning as radiopharmaceuticals to be daily used in hospitals. Ensuring the security of supply has been a challenge for many years and if several shortages occurred in the past, the last crises in 2007 and 2008 revealed more than ever the weakness of the current situation despite the efforts and warning that have been devoted to facing many obstacles including possible technical failures, incidents, transport constraints and licensing issues, as well as political threat for the use of HEU. It is time for having all stakeholders drawing the lessons of the crisis and considering all possible serious and realistic improvements on technical and organisational issues without neglecting the resulting economical and safety aspects. (author)

  6. Phosphate enhance recovery from wastewater by mechanism analysis and optimization of struvite settleability in fluidized bed reactor.

    Science.gov (United States)

    Fang, Ci; Zhang, Tao; Jiang, Rongfeng; Ohtake, Hisao

    2016-01-01

    Since phosphorus, a non-renewable and non-substitutable resource, has become the principal contributor and limiting factor to water eutrophication, achieving phosphorus removal and recovery from wastewater is pretty essential. Even though struvite crystallization process has been widely used for phosphate (P) recovery in wastewater treatment, its application is hampered by difficulties controlling small particle size and crystal growth. This study was conducted to control the settleability of struvite by calculating and predicting the struvite-settling percentage (Ps), which is always affected by the initial concentration of P (CP), solution pH (pH), reaction time (t), reaction temperature (T), agitation rate (Ar), and inlet flow velocity (vf) of the fluidized bed reactor. The results showed that the settleability of struvite could be enhanced by increasing T and decreasing pH, Ar, or vf, and would perform worse with overlong t or excessive CP. The dynamic variation process of the solution supersaturated index (SI) combined with the phase equilibrium theory and Ostwald ripening mechanism explained the above results sufficiently. The logistic model was chosen to predict the Ps under multi-factors, but the accuracy needs to be improved. PMID:27573918

  7. Phosphate enhance recovery from wastewater by mechanism analysis and optimization of struvite settleability in fluidized bed reactor

    Science.gov (United States)

    Fang, Ci; Zhang, Tao; Jiang, Rongfeng; Ohtake, Hisao

    2016-08-01

    Since phosphorus, a non-renewable and non-substitutable resource, has become the principal contributor and limiting factor to water eutrophication, achieving phosphorus removal and recovery from wastewater is pretty essential. Even though struvite crystallization process has been widely used for phosphate (P) recovery in wastewater treatment, its application is hampered by difficulties controlling small particle size and crystal growth. This study was conducted to control the settleability of struvite by calculating and predicting the struvite-settling percentage (Ps), which is always affected by the initial concentration of P (CP), solution pH (pH), reaction time (t), reaction temperature (T), agitation rate (Ar), and inlet flow velocity (vf) of the fluidized bed reactor. The results showed that the settleability of struvite could be enhanced by increasing T and decreasing pH, Ar, or vf, and would perform worse with overlong t or excessive CP. The dynamic variation process of the solution supersaturated index (SI) combined with the phase equilibrium theory and Ostwald ripening mechanism explained the above results sufficiently. The logistic model was chosen to predict the Ps under multi-factors, but the accuracy needs to be improved.

  8. Power Optimization Distribution and Control Strategies of Multistage Vanadium Redox Flow Battery Energy Storage Systems%多级钒电池储能系统的功率优化分配及控制策略

    Institute of Scientific and Technical Information of China (English)

    李辉; 付博; 杨超; 赵斌; 唐显虎

    2013-01-01

    为了更好利用储能系统平抑大容量风电场功率波动,提出采用多级全钒液流电池(vanadium redox flow battery,VRB)储能的功率优化分配控制策略.首先,在建立VRB等效电路基础上,采用交直流变换器级联多重双向直流变换器作为VRB储能系统接口,分别建立了以稳定直流母线电压为目标的DC/AC变换器矢量控制策略,以电池荷电状态为约束的VRB充放电切换的DC/DC变换器双闭环控制策略.其次,以每级电池组的荷电状态值作为吞吐功率的优选目标,以外部端电压作为电池安全充放电的约束条件,提出多级VRB组的功率优化分配策略.最后,以不同荷电状态(state of charge,SOC)值下的2级VRB储能系统为例,对其在风速波动情况下的风电功率平抑效果以及各个储能单元充放电运行性能进行仿真,并与功率平均分配策略进行对比.结果表明,所提出的多级VRB储能系统功率优化分配和控制策略能很好的平滑风电功率波动,又能减少单台VRB组的充放电次数,并确保电池工作于安全运行区域.%In order to make better use of energy storage system to reduce the fluctuation of active power for large-scale wind farm,this paper proposes the optimization power distribution control strategies of the multistage vanadium redox flow battery (VRB) storage.Firstly,based on the equivalent circuit of a VRB and by using the interface of the DC/AC converter cascade multiple bi-directional DC/DC converter,a vector control strategy of DC/AC converter is presented to keep the stable DC bus voltage,and a double closed loop control strategy of DC/DC converter is established to switch charge-discharge style as a constraint of state of charge (SOC) on a single VRB.Secondly,by taking SOC value of each battery as priority target selection of output power,and by using the limit of external terminal voltage as the constraint conditions for battery safety charging and discharging,an optimization

  9. Exploring the controls of soil biogeochemistry in a restored coastal wetland using object-oriented computer simulations of uptake kinetics and thermodynamic optimization in batch reactors

    Science.gov (United States)

    Payn, R. A.; Helton, A. M.; Poole, G.; Izurieta, C.; Bernhardt, E. S.; Burgin, A. J.

    2012-12-01

    Many hypotheses have been proposed to predict patterns of biogeochemical redox reactions based on the availability of electron donors and acceptors and the thermodynamic theory of chemistry. Our objective was to develop a computer model that would allow us to test various alternatives of these hypotheses against data gathered from soil slurry batch reactors, experimental soil perfusion cores, and in situ soil profile observations from the restored Timberlake Wetland in coastal North Carolina, USA. Software requirements to meet this objective included the ability to rapidly develop and compare different hypothetical formulations of kinetic and thermodynamic theory, and the ability to easily change the list of potential biogeochemical reactions used in the optimization scheme. For future work, we also required an object pattern that could easily be coupled with an existing soil hydrologic model. These requirements were met using Network Exchange Objects (NEO), our recently developed object-oriented distributed modeling framework that facilitates simulations of multiple interacting currencies moving through network-based systems. An initial implementation of the object pattern was developed in NEO based on maximizing growth of the microbial community from available dissolved organic carbon. We then used this implementation to build a modeling system for comparing results across multiple simulated batch reactors with varied initial solute concentrations, varied biogeochemical parameters, or varied optimization schemes. Among heterotrophic aerobic and anaerobic reactions, we have found that this model reasonably predicts the use of terminal electron acceptors in simulated batch reactors, where reactions with higher energy yields occur before reactions with lower energy yields. However, among the aerobic reactions, we have also found this model predicts dominance of chemoautotrophs (e.g., nitrifiers) when their electron donor (e.g., ammonium) is abundant, despite the

  10. Optimization on structural parameters of diesel SCR catalytic reactor%柴油机SCR催化器载体结构参数优化

    Institute of Scientific and Technical Information of China (English)

    龚金科; 张福杰; 鄂加强; 刘恒语; 杜佳; 陈韬; 江俊豪

    2012-01-01

    提出一种柴油机选择催化还原(SCR)催化器载体结构参数优化的设计方法,根据车用柴油机排量,将SCR催化器载体分为4类,选取载体体积、长度、目数、壁厚和涂层厚5个结构参数为设计变量,以高NO。转化率及低压力损失为优化目标,利用拉丁超立方实验设计选择样本点进行数值模拟,在构建的Kriging近似模型基础上,对载体结构参数采用改进的非支配排序遗传算法NSGA—II(non—dominatedsortinggeneticalgorithm—II)进行优化设计。结果表明:Kriging近似模型的拟合精度较高,结合NSGA—II算法对SCR催化器载体结构参数进行优化是可行的、有效的,不同排量下的优化结果均能够较好地满足设计要求。%The optimal design method of structural parameters for diesel urea-SCR was proposed. Accord- ing to the differences of diesel engine displacement, the urea-selective catalytic reactor can be divided into four subclasses. Taking high conversion ratio of NO and small pressure loss as the optimization goal, with monolith volume, length,cell per square inch,wall thickness and washcoat thickness as design variables, Latin Hypercube method was used to carry out sampling of parameters. The obtained samples were analyzed with numerical simula- tion. On this basis, the optimization was solved by NSGA-Ⅱ (non-dominated sorting genetic algorithm-Ⅱ ) , using Kriging model as the approximate model. The results show that the Kriging model has high fitting accuracy,dem- onstrate the efficiency and applicability of the optimal design method. The optimization results of different diesel engine displacement show that the method can obtain structural parameters which meet design requirements.

  11. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  12. Optimizing pin layout in transmutation rate of long-life FP with deuteride moderator for fast reactors

    International Nuclear Information System (INIS)

    Some types of Long-life FP (LLFP) assemblies are arranged with deuteride moderator pins at the 1st layer of radial blanket position in a demonstration class MOX-fuel core (thermal power is 1600MWth, core equivalent diameter is 2.2m, and core height is 1m), and annual transmutation rates have been evaluated. The calculation has been conducted by using three-dimensional continuations energy Monte Carlo code MVP and JENDL-3.3 library along with MVP-BURN as a burn-up calculation routine. In this study, neutron moderation and absorption effect has been taken into consideration by optimizing the layout of pins, which contains LLFP with zirconium deuteride or zirconium hydride moderators. The support factor, that is the ratio of the amount of generated LLFP to the transmuted LLFP, have been also evaluated for the same core. As a result, the optimized transmutation rate of 53% in 6 years has been achieved for the assembly when outer 90 pins are contain only zirconium deteride and inner 31 pins contain the mixture of LLFP and zirconium hydride with the volume ratio of LLFP to Zirconium moderator of 0.3, while the support factor of the core has been 2.5. (author)

  13. A high-throughput reactor system for optimization of Mo–V–Nb mixed oxide catalyst composition in ethane ODH

    KAUST Repository

    Zhu, Haibo

    2015-01-01

    75 Mo-V-Nb mixed oxide catalysts with a broad range of compositions were prepared by a simple evaporation method, and were screened for the ethane oxidative dehydrogenation (ODH) reaction. The compositions of these 75 catalysts were systematically changed by varying the Nb loading, and the Mo/V molar ratio. Characterization by XRD, XPS, H2-TPR and SEM revealed that an intimate structure is formed among the 3 components. The strong interaction among different components leads to the formation of a new phase or an "intimate structure". The dependency of conversion and selectivity on the catalyst composition was clearly demonstrated from the results of high-throughput testing. The optimized Mo-V-Nb molar composition was confirmed to be composed of a Nb content of 4-8%, a Mo content of 70-83%, and a V content of 12-25%. The enhanced catalytic performance of the mixed oxides is obviously due to the synergistic effects of the different components. The optimized compositions for ethane ODH revealed in our high-throughput tests and the structural information provided by our characterization studies can serve as the starting point for future efforts to improve the catalytic performance of Mo-V-Nb oxides. This journal is © The Royal Society of Chemistry.

  14. Optimization of carbon dioxide supply in raceway reactors: Influence of carbon dioxide molar fraction and gas flow rate.

    Science.gov (United States)

    Duarte-Santos, T; Mendoza-Martín, J L; Acién Fernández, F G; Molina, E; Vieira-Costa, J A; Heaven, S

    2016-07-01

    Influence of CO2 composition and gas flow rate to control pH in a pilot-scale raceway producing Scenedesmus sp. was studied. Light and temperature determined the biomass productivity whereas neither the CO2 molar fraction nor the gas flow rate used influenced it; because pH was always controlled and carbon limitation did not take place. The CO2 molar fraction and the gas flow rate influenced carbon loss in the system. At low CO2 molar fraction (2-6%) or gas flow rate (75-100l·min(-1)) the carbon efficiency in the sump was higher than 95%, 85% of the injected carbon being transformed into biomass. Conversely, at high CO2 molar fraction (14%) or gas flow rate (150l·min(-1)) the carbon efficiency in the sump was lower than 67%, 32% of the carbon being fixed as biomass. Analysis here reported allows the pH control to be optimized and production costs to be reduced by optimizing CO2 efficiency.

  15. Atmospheric pressure plasma chemical vapor deposition reactor for 100 mm wafers, optimized for minimum contamination at low gas flow rates

    Science.gov (United States)

    Anand, Venu; Nair, Aswathi R.; Shivashankar, S. A.; Mohan Rao, G.

    2015-08-01

    Gas discharge plasmas used for thinfilm deposition by plasma-enhanced chemical vapor deposition (PECVD) must be devoid of contaminants, like dust or active species which disturb the intended chemical reaction. In atmospheric pressure plasma systems employing an inert gas, the main source of such contamination is the residual air inside the system. To enable the construction of an atmospheric pressure plasma (APP) system with minimal contamination, we have carried out fluid dynamic simulation of the APP chamber into which an inert gas is injected at different mass flow rates. On the basis of the simulation results, we have designed and built a simple, scaled APP system, which is capable of holding a 100 mm substrate wafer, so that the presence of air (contamination) in the APP chamber is minimized with as low a flow rate of argon as possible. This is examined systematically by examining optical emission from the plasma as a function of inert gas flow rate. It is found that optical emission from the plasma shows the presence of atmospheric air, if the inlet argon flow rate is lowered below 300 sccm. That there is minimal contamination of the APP reactor built here, was verified by conducting an atmospheric pressure PECVD process under acetylene flow, combined with argon flow at 100 sccm and 500 sccm. The deposition of a polymer coating is confirmed by infrared spectroscopy. X-ray photoelectron spectroscopy shows that the polymer coating contains only 5% of oxygen, which is comparable to the oxygen content in polymer deposits obtained in low-pressure PECVD systems.

  16. Design and techno-economic optimization of a stand-alone PV (photovoltaic)/FC (fuel cell)/battery hybrid power system connected to a wastewater-to-hydrogen processor

    International Nuclear Information System (INIS)

    A wastewater treatment process is developed as a heat-integrated fuel processor to produce hydrogen. If the hydrogen flow is directly connected to the PEMFC (proton exchange membrane fuel cell), then a stand-alone PV/FC/battery hybrid power system is developed to meet the daily load demand. According to the prescribed scenarios such as wastewater conditions and weather patterns, the reliability of the power supply is expressed in terms of the LPSP (loss of power supply probability). To address the lowest cost of electricity, an economic sizing model with regard to the LCE (levelized cost of energy) is taken into account. Regarding the trade-off between investment costs and power reliability, the techno-economic optimization algorithm for the minimization of the LCE subject to LPSP is used to determine the optimum hybrid power system configuration. - Highlights: • A wastewater treatment process is developed as a heat-integrated fuel processor to produce hydrogen. • The performance of the HPG (Hybrid power generation) system is evaluated on the basis of reliability of the power supply. • The optimization of the system size is subsequently predicted on the minimum LCE (levelized cost of energy). • An optimal compromise between investment costs and power reliability is investigated

  17. 电动公交车换电站--电池充电站优化规划%Optimal Planning of Battery Charging and Exchange Stations for Electric Vehicles

    Institute of Scientific and Technical Information of China (English)

    钱斌; 石东源; 谢平平; 朱林

    2014-01-01

    充电设施的规划与建设是解决电动汽车发展瓶颈的重要问题。电动汽车在公共交通领域发展迅速,并广泛采用换电模式。文中充分考虑了电动公交汽车换电电量需求和充换电行为,提出了一种换电站-电池充电站建设模式,并给出了相应的优化规划方法。该方法首先使用近邻传播聚类算法对换电需求点进行空间聚类,以确定电池充电站的站址和规模,并利用化石燃料与电能的热值关系,将当前柴油公交车日消耗能量折算成电能以确定换电电量需求。然后,利用排队论方法对电池充电站内的工作情形进行建模,提出以拒绝服务率为主要约束,以综合建设成本最小为目标的优化模型。最后,以某城市实际统计数据为例给出了该市公交汽车换电站、电池充电站以及其充电设备、换电设备、电池的规划方案,为电动公交车充、换电站的实际规划提供参考。%The planning and deployment of electric vehicle battery charging devices is an important problem in tackling the bottleneck of electric vehicles.Although the charging mode is widely preferred,the exchange mode is still popular with public transport.A battery charging-exchange station construction mode is proposed along with the corresponding optimal planning strategy by taking the electric bus demand into consideration.The affinity propagation clustering algorithm is used to determine the sizing and siting of the battery charging stations.In order to identify the bus electricity demand,daily fuel consumption is converted into equivalent electricity usage.The queuing theory is put forward to model the daily management of battery charging stations.After that,a minimum construction cost optimization model is built with the service denying rate as the major constraint.Finally,actual statistics of a city are taken as an example to determine the quantity of charge/exchange devices and

  18. Synthesis and optimization of tin dioxide/functionalized multi-walled carbon nanotube composites as anode in lithium-ion battery

    International Nuclear Information System (INIS)

    In this paper, nanocomposite electrodes for rechargeable Lithium-ion battery composed of tin dioxide (SnO2) and multi-walled carbon nanotubes (MWCNTs) were prepared using the chemical deposition method with a subsequent sintering process. The as-prepared hybrids were characterized by thermal gravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction and transmission electron microscopy. The results showed that the size of pure SnO2 particles was ∼5 nm and hybrids presented a uniform dispersion of SnO2 nanoparticles on the surfaces of the MWCNTs. The electrochemical properties of the composites were researched through a cyclic voltammetry and a galvanostatic charge–discharge test. It was found that the electrochemical performance of the composite was strongly dependent on the content of MWCNTs in the composites. The SnO2/MWCNT composite with 18.40 wt% MWCNTs gave the best performance, exhibiting a relatively higher reversible capacity of 475 mAh g−1 and an extended capacity retention of 65% even after 30 cycles at a current density of 78.2 mA g−1. - Highlights: • SnO2/MWCNT nanocomposites were prepared using chemical deposition method. • SnO2 nanoparticles presented a uniformly dispersion on the surfaces of MWCNTs. • SnO2/MWCNT composite anode exhibited high reversible capacity for rechargeable Li-ion battery

  19. Collecting battery data with Open Battery

    OpenAIRE

    Jones, Gareth L.; Harrison, Peter G.

    2012-01-01

    In this paper we present Open Battery, a tool for collecting data on mobile phone battery usage, describe the data we have collected so far and make some observations. We then introduce the fluid queue model which we hope may prove a useful tool in future work to describe mobile phone battery traces.

  20. Optimization of C/N Ratio and Inducers for Wastewater Paper Industry Treatment Using Trametes versicolor Immobilized in Bubble Column Reactor

    Directory of Open Access Journals (Sweden)

    Aura M. Pedroza-Rodríguez

    2013-01-01

    Full Text Available C/N ratio and MnSO4 and CuSO4 concentrations were optimized for decolorization and chemical oxygen demand (COD removal of bleached Kraft pulp mill effluent by Trametes versicolor immobilized in polyurethane foam. Statistical differences (P<0.0001 at high C/N ratios (169, 2 mM CuSO4, and 0.071 mM MnSO4 were determined. Decolorization of 60.5%, COD removal of 55%, laccase (LAC 60 U/L, and manganese peroxidase (MnP 8.4 U/L were obtained. Maximum of decolorization (82%, COD removal (83%, LAC (443.5 U/L, and MnP (18 U/L activities at C/N ratio of 405 (6.75 mM CuSO4 and 0.22 mM MnSO4 was achieved in step 7 at 4 d. Positive correlation between the decolorization, COD removal, and enzymatic activity was found (P<0.0001. T. versicolor bioremediation capacity was evaluated in bubble column reactor during 8 d. Effluent was adjusted according to optimized parameters and treated at 25°C and air flow of 800 mL/min. Heterotrophic bacteria growth was not inhibited by fungus. After 4 d, 82% of COD reduction and 80% decolorization were recorded. Additionally, enzymatic activity of LAC (345 U/L and MnP (78 U/L was observed. The COD reduction and decolorization correlated positively (P<0.0001 with enzymatic activity. Chlorophenol removal was 98% of pentachlorophenol (PCP, 92% of 2,4,5-trichlorophenol (2,4,5-TCP, 90% of 3,4-dichlorophenol (3,4-DCP, and 99% of 4-chlorophenols (4CP.

  1. Configuration Optimization of Capacity of Standalone PV-Wind-Diesel-Battery Hybrid Microgrid%独立风光柴储微网系统容量优化配置

    Institute of Scientific and Technical Information of China (English)

    丁明; 王波; 赵波; 陈自年

    2013-01-01

    独立微网系统通过内部各个电源对本地区负荷进行供电,其主要目标是最大限度地增强发电功率与负荷之间的匹配性.为保证供电可靠性同时提高整个微网系统的经济性,需根据现有的天气和资源条件对系统的容量配置进行优化设计,选取最优的电源容量组合.为此,建立了独立风光柴储微网系统中各个电源的数学模型,以及包含投资成本和不同费用的经济性模型.根据系统的调度策略和约束条件,将不同电源的个数作为变量,以综合成本费用最小为优化目标,利用遗传算法求解系统中各个电源的最优容量配置.算例结果验证了模型和算法的合理性.%Standalone PV-wind-diesel-battery hybrid microgrid supplies power to local loads by power sources within the microgrid,and the primary target is to enhance the accouplement between the generated power and the load maximally.To improve the economy of whole microgrid while the power supply reliability is ensured,it is necessary to perform optimal design of capacity configuration of the microgrid according to existing conditions in whether and resources and to choose optimal source capacity combination.Mathematical models for different kinds of power sources within the standalone PV-wind-diesel-battery hybrid microgrid are established respectively,and two economic models of investment cost and different expenses are built too.Based on the dispatching strategy and constraints of this hybrid system,the numbers of different power sources are taken as variables and the minimum composite cost and expenses as optimization objective,and then the optimal capacity configurations of different power sources in the system are solved by genetic algorithm.The reasonableness of the proposed models is verified by case study results.

  2. Anammox moving bed biofilm reactor pilot at the 26th Ward wastewater treatment plants in Brooklyn, New York: start-up, biofilm population diversity and performance optimization.

    Science.gov (United States)

    Mehrdad, M; Park, H; Ramalingam, K; Fillos, J; Beckmann, K; Deur, A; Chandran, K

    2014-01-01

    New York City Environmental Protection in conjunction with City College of New York assessed the application of the anammox process in the reject water treatment using a moving bed biofilm reactor (MBBR) located at the 26th Ward wastewater treatment plant, in Brooklyn, NY. The single-stage nitritation/anammox MBBR was seeded with activated sludge and consequently was enriched with its own 'homegrown' anammox bacteria (AMX). Objectives of this study included collection of additional process kinetic and operating data and assessment of the effect of nitrogen loading rates on process performance. The initial target total inorganic nitrogen removal of 70% was limited by the low alkalinity concentration available in the influent reject water. Higher removals were achieved after supplementing the alkalinity by adding sodium hydroxide. Throughout startup and process optimization, quantitative real-time polymerase chain reaction (qPCR) analyses were used for monitoring the relevant species enriched in the biofilm and in the suspension. Maximum nitrogen removal rate was achieved by stimulating the growth of a thick biofilm on the carriers, and controlling the concentration of dissolved oxygen in the bulk flow and the nitrogen loading rates per surface area; all three appear to have contributed in suppressing nitrite-oxidizing bacteria activity while enriching AMX density within the biofilm.

  3. A quantitative analysis of a risk impact due to a starting time extension of the emergency diesel generator in optimized power reactor-1000

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ho-Gon [Korea Atomic Energy Research Institute, P. O. Box 105, Yusung, 305-606, Taejeon (Korea, Republic of)]. E-mail: hglim@kaeri.re.kr; Yang, Joon-Eon [Korea Atomic Energy Research Institute, P. O. Box 105, Yusung, 305-606, Taejeon (Korea, Republic of)]. E-mail: jeyang@kaeri.re.kr; Hwang, Mee-Jeong [Korea Atomic Energy Research Institute, P. O. Box 105, Yusung, 305-606, Taejeon (Korea, Republic of)]. E-mail: mjhwang@kaeri.re.kr

    2007-07-15

    An emergency diesel generator (EDG) is the ultimate electric power supply source for the operation of emergency engineered safety features when a nuclear power plant experiences a loss of off-site power (LOOP). If a loss of coolant accident (LOCA) with a simultaneous LOOP occurs, the EDG should be in the state of a full power within 10 s, which is a prescribed regulatory requirement in the technical specifications (TS) of the Optimized Power Reactor-1000 (OPR-1000). Recently, the US nuclear regulatory commission (NRC) has been preparing a new risk-informed emergency core cooling system (ECCS) rule called 10 CFR 50.46. The new rule redefines the size for the design basis LOCA and it relaxes some of the requirements such as the single failure criteria, simultaneous LOOP, and the methods of analysis. The revision of the ECCS rule will provide flexibility for plant changes if the plant risks are checked and balanced with the specified criteria. The present study performed a quantitative analysis of the plant risk impact due to the EDG starting time extension given that the new rule will be applied to OPR-1000. The thermal-hydraulic analysis and OPR-1000 probabilistic safety assessment (PSA) model were combined to estimate the whole plant risk impact. Also, sensitivity analyses were implemented for the important uncertainty parameters.

  4. Optimization of the pyrolysis process of empty fruit bunch (EFB) in a fixed-bed reactor through a central composite design (CCD)

    Science.gov (United States)

    Mohamed, Alina Rahayu; Hamzah, Zainab; Daud, Mohamed Zulkali Mohamed

    2014-07-01

    The production of crude palm oil from the processing of palm fresh fruit bunches in the palm oil mills in Malaysia hs resulted in a huge quantity of empty fruit bunch (EFB) accumulated. The EFB was used as a feedstock in the pyrolysis process using a fixed-bed reactor in the present study. The optimization of process parameters such as pyrolysis temperature (factor A), biomass particle size (factor B) and holding time (factor C) were investigated through Central Composite Design (CCD) using Stat-Ease Design Expert software version 7 with bio-oil yield considered as the response. Twenty experimental runs were conducted. The results were completely analyzed by Analysis of Variance (ANOVA). The model was statistically significant. All factors studied were significant with p-values production of bio-oil from EFB pyrolysis process. A quadratic model equation was developed and employed to predict the highest theoretical bio-oil yield. The maximum bio-oil yield of 46.2 % was achieved at pyrolysis temperature of 442.15 °C using the EFB particle size of 866 μm which corresponded to the EFB particle size in the range of 710-1000 μm and holding time of 483 seconds.

  5. Optimal Conditions for Fast Charging and Long Cycling Stability of Silicon Microwire Anodes for Lithium Ion Batteries, and Comparison with the Performance of Other Si Anode Concepts

    Directory of Open Access Journals (Sweden)

    Enrique Quiroga-González

    2013-10-01

    Full Text Available Cycling tests under various conditions have been performed for lithium ion battery anodes made from free-standing silicon microwires embedded at one end in a copper current collector. Optimum charging/discharging conditions have been found for which the anode shows negligible fading (< 0.001% over 80 cycles; an outstanding result for this kind of anodes. Several performance parameters of the anode have been compared to the ones of other Si anode concepts, showing that especially the capacity as well as the rates of charge flow per nominal area of anode are the highest for the present anode. With regard to applications, the specific parameters per area are more important than the specific gravimetric parameters like the gravimetric capacity, which is good for comparing the capacity between materials but not enough for comparing between anodes.

  6. Alkaline battery operational methodology

    Energy Technology Data Exchange (ETDEWEB)

    Sholklapper, Tal; Gallaway, Joshua; Steingart, Daniel; Ingale, Nilesh; Nyce, Michael

    2016-08-16

    Methods of using specific operational charge and discharge parameters to extend the life of alkaline batteries are disclosed. The methods can be used with any commercial primary or secondary alkaline battery, as well as with newer alkaline battery designs, including batteries with flowing electrolyte. The methods include cycling batteries within a narrow operating voltage window, with minimum and maximum cut-off voltages that are set based on battery characteristics and environmental conditions. The narrow voltage window decreases available capacity but allows the batteries to be cycled for hundreds or thousands of times.

  7. Lithium Ion Batteries

    Science.gov (United States)

    1997-01-01

    Lithium ion batteries, which use a new battery chemistry, are being developed under cooperative agreements between Lockheed Martin, Ultralife Battery, and the NASA Lewis Research Center. The unit cells are made in flat (prismatic) shapes that can be connected in series and parallel to achieve desired voltages and capacities. These batteries will soon be marketed to commercial original-equipment manufacturers and thereafter will be available for military and space use. Current NiCd batteries offer about 35 W-hr/kg compared with 110 W-hr/kg for current lithium ion batteries. Our ultimate target for these batteries is 200 W-hr/kg.

  8. N Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The last of Hanfordqaodmasdkwaspemas7ajkqlsmdqpakldnzsdflss nine plutonium production reactors to be built was the N Reactor.This reactor was called a dual purpose...

  9. Design and optimization of Artificial Neural Networks for the modelling of superconducting magnets operation in tokamak fusion reactors

    Science.gov (United States)

    Froio, A.; Bonifetto, R.; Carli, S.; Quartararo, A.; Savoldi, L.; Zanino, R.

    2016-09-01

    In superconducting tokamaks, the cryoplant provides the helium needed to cool different clients, among which by far the most important one is the superconducting magnet system. The evaluation of the transient heat load from the magnets to the cryoplant is fundamental for the design of the latter and the assessment of suitable strategies to smooth the heat load pulses, induced by the intrinsically pulsed plasma scenarios characteristic of today's tokamaks, is crucial for both suitable sizing and stable operation of the cryoplant. For that evaluation, accurate but expensive system-level models, as implemented in e.g. the validated state-of-the-art 4C code, were developed in the past, including both the magnets and the respective external cryogenic cooling circuits. Here we show how these models can be successfully substituted with cheaper ones, where the magnets are described by suitably trained Artificial Neural Networks (ANNs) for the evaluation of the heat load to the cryoplant. First, two simplified thermal-hydraulic models for an ITER Toroidal Field (TF) magnet and for the ITER Central Solenoid (CS) are developed, based on ANNs, and a detailed analysis of the chosen networks' topology and parameters is presented and discussed. The ANNs are then inserted into the 4C model of the ITER TF and CS cooling circuits, which also includes active controls to achieve a smoothing of the variation of the heat load to the cryoplant. The training of the ANNs is achieved using the results of full 4C simulations (including detailed models of the magnets) for conventional sigmoid-like waveforms of the drivers and the predictive capabilities of the ANN-based models in the case of actual ITER operating scenarios are demonstrated by comparison with the results of full 4C runs, both with and without active smoothing, in terms of both accuracy and computational time. Exploiting the low computational effort requested by the ANN-based models, a demonstrative optimization study has been

  10. ADS 嬗变堆冷却剂及燃料优化布置的蒙特卡罗模拟%Monte Carlo Simulation of ADS Transmutation Reactor Coolant and Fuel Optimal Arrangement

    Institute of Scientific and Technical Information of China (English)

    魏强林; 王爱星; 刘义保; 杨波; 钮云龙; 郭晗

    2013-01-01

    为探索我国核裂变能可持续发展的新技术途径,利用MCNP5程序,建立了加速器驱动次临界系统(ADS)嬗变堆堆芯结构数学模型,模拟计算嬗变堆中分别使用氦气、液态铅、液态钠3种不同冷却剂对反应堆内局部中子能谱的影响,得出用液态铅作为ADS反应堆的冷却剂效果最佳的结论,提出了可提高嬗变堆内嬗变率的非均匀燃料组件排布的优化方案。%For exploring new technical approach of sustainable development of nuclear fission energy , the sub-ject used the MCNP5 program to establish mathematical model of accelerator driven system (ADS) transmuta-tion reactor core, and calculate influence on reactor local neutron spectrum of transmutation reactor , in which used three different coolant such as helium , liquid lead and liquid sodium.The results show that cooling effect of liquid lead is the best for ADS reactor , and then, a non-uniform optimization plan of fuel assembly is pro-posed to improve the reactor transmutation rate .

  11. 计及服务可用性的电动汽车换电站容量优化配置%Optimal Capacity Configuration of Electric Vehicle Battery Swapping Station Considering Service Availability

    Institute of Scientific and Technical Information of China (English)

    路欣怡; 刘念; 汤庆峰; 张建华

    2014-01-01

    Battery swapping has become one of the most important ways to supply energy to electric vehicles (EVs),since it takes a very short time to replace fully recharged EV battery (EVB) packs and is convenient to manage.It leads to growing market penetration of the EVs to develop the battery swapping station (BSS).The optimal capacity configuration of electric vehicle battery swapping station,which is able to recharge the depleted EVB packs locally,is studied.Firstly,the system structure of the swapping station system as well as the operation strategy of“charge and swap"is described and two evaluation indices of service availability are proposed.Secondly,the timing simulation model for swapping station operation states is analyzed.According to the output of the model,service availability indices are calculated.A mathematical model is developed, with the equipment annual cost as the objective function and the scale and service availability as the constraints.The differential evolution(DE) algorithm is used to solve the mathematical model.Finally,the optimal configuration of a case in point is made.With two different days” swapping demand randomly taken,the indices of swapping service availability are calculated and the state of the BSS in each period is analyzed.And the sensitivity of the result of configuration is briefly treated. This work is supported by National Natural Science Foundation of China(No.5 1277067)and the Project of Capital SCI &TEC Resources Platform (No.Z131 1 10000613053).%动力电池换电模式由于其换电过程所需时长远小于充电过程、动力电池充电便于统一管理等优点,成为电动汽车能量补充的重要方式,推进换电站的建设有利于电动汽车的普及。针对可就地向动力电池组充电的换电站容量优化配置展开研究。首先介绍换电站的系统结构和“即换即充”的运行策略,提出服务可用性的评价指标;然后分析换电站运行状态的

  12. Iris reactor conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Carelli, M.D.; Conway, L.E.; Petrovic, B.; Paramonov, D.V. [Westinghouse Electric Comp., Pittsburgh, PA (United States); Galvin, M.; Todreas, N.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Lombardi, C.V.; Maldari, F.; Ricotti, M.E. [Politecnico di Milano, Milan (Italy); Cinotti, L. [Ansaldo SpA, Genoa (Italy)

    2001-07-01

    IRIS (International Reactor Innovative and Secure) is a modular, integral, light water cooled, low-to-medium power (100-350 MWe) reactor which addresses the requirements defined by the US DOE for Generation IV reactors, i.e., proliferation resistance, enhanced safety, improved economics and fuel cycle sustainability. It relies on the proven technology of light water reactors and features innovative engineering, but it does not require new technology development. This paper discusses the current reference IRIS design, which features a 1000 MWt thermal core with proven 5%-enriched uranium oxide fuel and five-year long straight burn fuel cycle, integral reactor vessel housing helical tube steam generators and immersed spool pumps. Other major contributors to the high level of safety and economic attractiveness are the safety by design and optimized maintenance approaches, which allow elimination of some classes of accidents, lower capital cost, long operating cycle, and high capacity factors. (author)

  13. Design of Intelligent Vehicle Terminal (IVT) for Electric Cars and Optimization of Battery Management System%电动车IVT功能设计及电池管理系统的优化

    Institute of Scientific and Technical Information of China (English)

    周封; 杨玉萍; 王晨光; 王丙全

    2012-01-01

    In view of the lack of special electric motor car IVT, by analysing the functions and definition of IVT for vehicles with oil fuel in this paper and with the differences between electric cars and oil fuel vehicles, the func-tionns of IVT for electric cars which includes the battery management are identified. The remaining power is influenced by the emf AND the -temperature of the battery and the results are of biases. Fuzzy rules for the disturbance factor emf and temperature are formulated based on the Mamdani algorithm, the bias correction factor is obtained by the method of centroid defuzzification to correct the calculated value, and the remaining power calculated simulation model is established to improve the value. The results show that the error of optimized remaining power management system is within 5% and it can meet the demands of the battery management in TVT for electric cars.%针对国内缺乏专用的电动车智能车载终端(IVT)的问题,通过分析普通车载终端的各种定义和功能,结合电动车在动力能源上与燃油车的不同之处,确定出应具有包括预估电池剩余电量功能在内的电动车IVT功能.并对电池剩余电量的预估受电池温度和电池电动势等因数影响会产生较大偏差的问题,采用Mamdani算法对电动势和温度干扰因数制定模糊控制规则,利用重心法反模糊化获得偏差修正因子,建立了电池剩余电量预估计系统仿真模型,从而对剩余电量估算值进行修正.仿真结果表明优化之后的系统剩余电量预测值的误差范围控制在5%以内,能满足电动车智能车载终端剩余电量的估算要求.

  14. Optimization method development of the core characteristics of a fast reactor in order to explore possible high performance solutions (a solution being a consistent set of fuel, core, system and safety)

    International Nuclear Information System (INIS)

    In the study of any new nuclear reactor, the design of the core is an important step. However designing and optimising a reactor core is quite complex as it involves neutronics, thermal-hydraulics and fuel thermomechanics and usually design of such a system is achieved through an iterative process, involving several different disciplines. In order to solve quickly such a multi-disciplinary system, while observing the appropriate constraints, a new approach has been developed to optimise both the core performance (in-cycle Pu inventory, fuel burn-up, etc...) and the core safety characteristics (safety estimators) of a Fast Neutron Reactor. This new approach, called FARM (Fast Reactor Methodology) uses analytical models and interpolations (Meta-models) from CEA reference codes for neutronics, thermal-hydraulics and fuel behaviour, which are coupled to automatically design a core based on several optimization variables. This global core model is then linked to a genetic algorithm and used to explore and optimise new core designs with improved performance. Consideration has also been given to which parameters can be best used to define the core performance and how safety can be taken into account.This new approach has been used to optimize the design of three concepts of Gas cooled Fast Reactor (GFR). For the first one, using a SiC/SiCf-cladded carbide-fuelled helium-bonded pin, the results demonstrate that the CEA reference core obtained with the traditional iterative method was an optimal core, but among many other possibilities (that is to say on the Pareto front). The optimization also found several other cores which exhibit some improved features at the expense of other safety or performance estimators. An evolution of this concept using a 'buffer', a new technology being developed at CEA, has hence been introduced in FARM. The FARM optimisation produced several core designs using this technology, and estimated their performance. The results obtained show that

  15. Thermal battery with CO2 compression heat pump: Techno-economic optimization of a high-efficiency Smart Grid option for buildings

    DEFF Research Database (Denmark)

    Blarke, Morten; Yazawa, Kazuaki; Shakouri, Ali;

    2012-01-01

    Increasing penetration levels of wind and solar power in the energy system call for the development of Smart Grid enabling technologies. As an alternative to expensive electro-chemical and mechanical storage options, the thermal energy demand in buildings offers a cost-effective option for interm...... CO2 emissions (reduced to zero), and lower operational costs (reduced by 72%). The results indicate that TB may be the most cost-effective Smart Grid enabling option for supporting higher penetration levels of intermittent renewables in the energy system.......Increasing penetration levels of wind and solar power in the energy system call for the development of Smart Grid enabling technologies. As an alternative to expensive electro-chemical and mechanical storage options, the thermal energy demand in buildings offers a cost-effective option...... for intermittency-friendly electricity consumption patterns. Combining hot and cold thermal storages with new high-pressure compressor technology that allows for flexible and simultaneous production of useful heat and cooling, the paper introduces and investigates the high-efficiency thermal battery (TB) concept...

  16. Optimization of the pyrolysis process of empty fruit bunch (EFB) in a fixed-bed reactor through a central composite design (CCD)

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Alina Rahayu; Hamzah, Zainab; Daud, Mohamed Zulkali Mohamed [School of Bioprocess Engineering, Jejawi Complex of Academics (3), UniMAP, 02600 Arau Perlis (Malaysia)

    2014-07-10

    The production of crude palm oil from the processing of palm fresh fruit bunches in the palm oil mills in Malaysia hs resulted in a huge quantity of empty fruit bunch (EFB) accumulated. The EFB was used as a feedstock in the pyrolysis process using a fixed-bed reactor in the present study. The optimization of process parameters such as pyrolysis temperature (factor A), biomass particle size (factor B) and holding time (factor C) were investigated through Central Composite Design (CCD) using Stat-Ease Design Expert software version 7 with bio-oil yield considered as the response. Twenty experimental runs were conducted. The results were completely analyzed by Analysis of Variance (ANOVA). The model was statistically significant. All factors studied were significant with p-values < 0.05. The pyrolysis temperature (factor A) was considered as the most significant parameter because its F-value of 116.29 was the highest. The value of R{sup 2} was 0.9564 which indicated that the selected factors and its levels showed high correlation to the production of bio-oil from EFB pyrolysis process. A quadratic model equation was developed and employed to predict the highest theoretical bio-oil yield. The maximum bio-oil yield of 46.2 % was achieved at pyrolysis temperature of 442.15 °C using the EFB particle size of 866 μm which corresponded to the EFB particle size in the range of 710–1000 μm and holding time of 483 seconds.

  17. Flow Battery System Design for Manufacturability.

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, Tracy Louise; Meacham, Paul Gregory; Perry, David; Broyles, Robin S.; Hickey, Steven; Hernandez, Jacquelynne

    2014-10-01

    Flow battery energy storage systems can support renewable energy generation and increase energy efficiency. But, presently, the costs of flow battery energy storage systems can be a significant barrier for large-scale market penetration. For cost- effective systems to be produced, it is critical to optimize the selection of materials and components simultaneously with the adherence to requirements and manufacturing processes to allow these batteries and their manufacturers to succeed in the market by reducing costs to consumers. This report analyzes performance, safety, and testing requirements derived from applicable regulations as well as commercial and military standards that would apply to a flow battery energy storage system. System components of a zinc-bromine flow battery energy storage system, including the batteries, inverters, and control and monitoring system, are discussed relative to manufacturing. The issues addressed include costs and component availability and lead times. A service and support model including setup, maintenance and transportation is outlined, along with a description of the safety-related features of the example flow battery energy storage system to promote regulatory and environmental, safety, and health compliance in anticipation of scale manufacturing.

  18. Nanostructured Materials for Li-Ion Batteries and Beyond

    Directory of Open Access Journals (Sweden)

    Xifei Li

    2016-04-01

    Full Text Available This Special Issue “Nanostructured Materials for Li-Ion Batteries and Beyond” of Nanomaterials is focused on advancements in the synthesis, optimization, and characterization of nanostructured materials, with an emphasis on the application of nanomaterials for building high performance Li-ion batteries (LIBs and future systems.[...

  19. Nanostructured Materials for Li-Ion Batteries and Beyond

    OpenAIRE

    Xifei Li; Xueliang Sun

    2016-01-01

    This Special Issue “Nanostructured Materials for Li-Ion Batteries and Beyond” of Nanomaterials is focused on advancements in the synthesis, optimization, and characterization of nanostructured materials, with an emphasis on the application of nanomaterials for building high performance Li-ion batteries (LIBs) and future systems.[...

  20. Efficient Electrolytes for Lithium-Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    Natarajan eAngulakshmi

    2015-05-01

    Full Text Available This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium-sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium-sulfur batteries. The electrolytes for lithium-sulfur batteries are broadly classified as (i non-aqueous liquid electrolytes, (ii ionic liquids, (iii solid polymer and (iv glass-ceramic electrolytes. This article presents the properties, advantages and limitations of each type of electrolytes. Also the importance of electrolyte additives on the electrochemical performance of Li-S cells is discussed.

  1. Modeling and optimization of stand-alone hybrid wind/PV/battery power system%独立风-光-蓄混合发电系统的建模与优化

    Institute of Scientific and Technical Information of China (English)

    李冲; 郑源; 陆云; 朱大胜; 宋晨光

    2014-01-01

    为缓解乌鲁木齐地区环境污染状况,系统地研究了该地区独立风-光-蓄混合发电系统,提出了基于直流总线的独立风-光-蓄混合发电系统结构,对混合系统中的风力发电机、光伏模块及铅酸蓄电池等关键部件进行建模,经济模型采用总净现值成本和平准化能源成本模型,可靠性模型采用负荷失电率.依据乌鲁木齐地区风能、太阳能和户用负载数据,利用遗传算法对该地区独立风-光-蓄混合发电系统进行优化设计.结果表明:独立风-光-蓄混合发电作为一种新型发电方式,可以减少环境空气中总悬浮颗粒物、二氧化硫和氮氧化物等污染物的排放.优化的混合发电系统包括1台风力发电机、12.5611 m2的光伏模块和14.7019 kW·h的铅酸蓄电池,负荷失电率为0.0198,系统最小总成本为87262元.%In order to alleviate environmental pollution in Urumqi,a stand-alone hybrid wind/PV/ba-ttery power system was systematically studied for this region;as a result,a DC bus-based new system was proposed.The wind turbines,PV modules and lead-acid batteries in the system were modeled re-spectively,and the two principal economic models include the total net present cost (NPC)and the levelized cost of energy (LCE).At the same time,the reliability of the system was expressed in terms of loss of power supply probability (LPSP).The hybrid system design was optimized by means of ge-netic algorithm (GA)with a series of data of wind speed,solar radiation and user load in that region. As a result,the proposed stand-alone hybrid wind/PV/battery power system can be served as a new type of power generation in Urumqi to reduce the emissions of total suspended particulate (TSP ), sulfur dioxide (SO2)and nitrogen oxides (NOx)etc.The optimal hybrid system consists of one wind turbine with 1 kW capacity,12.561 1 m2 PV module and batteries with 14.701 9 kW·h capacity.The system has a loss of power

  2. Optimization of a Chemical Reaction Train

    Directory of Open Access Journals (Sweden)

    Bahar Sansar

    2010-01-01

    Full Text Available This project consists of the optimization of a chemical reactor train. The reactor considered here is the continuous stirred tank reactor (CSTR, one of the reactor models used in engineering. Given the design equation for the CSTR and the cost function for a reactor, the following values are determined; the optimum number of reactors in the reaction train, the volume of each reactor and the total cost.

  3. Optimization of a Chemical Reaction Train

    OpenAIRE

    Bahar Sansar

    2010-01-01

    This project consists of the optimization of a chemical reactor train. The reactor considered here is the continuous stirred tank reactor (CSTR), one of the reactor models used in engineering. Given the design equation for the CSTR and the cost function for a reactor, the following values are determined; the optimum number of reactors in the reaction train, the volume of each reactor and the total cost.

  4. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  5. Solar-rechargeable battery based on photoelectrochemical water oxidation: Solar water battery.

    Science.gov (United States)

    Kim, Gonu; Oh, Misol; Park, Yiseul

    2016-01-01

    As an alternative to the photoelectrochemical water splitting for use in the fuel cells used to generate electrical power, this study set out to develop a solar energy rechargeable battery system based on photoelectrochemical water oxidation. We refer to this design as a "solar water battery". The solar water battery integrates a photoelectrochemical cell and battery into a single device. It uses a water oxidation reaction to simultaneously convert and store solar energy. With the solar water battery, light striking the photoelectrode causes the water to be photo-oxidized, thus charging the battery. During the discharge process, the solar water battery reduces oxygen to water with a high coulombic efficiency (>90%) and a high average output voltage (0.6 V). Because the reduction potential of oxygen is more positive [E(0) (O2/H2O) = 1.23 V vs. NHE] than common catholytes (e.g., iodide, sulfur), a high discharge voltage is produced. The solar water battery also exhibits a superior storage ability, maintaining 99% of its specific discharge capacitance after 10 h of storage, without any evidence of self-discharge. The optimization of the cell design and configuration, taking the presence of oxygen in the cell into account, was critical to achieving an efficient photocharge/discharge. PMID:27629362

  6. Solar-rechargeable battery based on photoelectrochemical water oxidation: Solar water battery.

    Science.gov (United States)

    Kim, Gonu; Oh, Misol; Park, Yiseul

    2016-01-01

    As an alternative to the photoelectrochemical water splitting for use in the fuel cells used to generate electrical power, this study set out to develop a solar energy rechargeable battery system based on photoelectrochemical water oxidation. We refer to this design as a "solar water battery". The solar water battery integrates a photoelectrochemical cell and battery into a single device. It uses a water oxidation reaction to simultaneously convert and store solar energy. With the solar water battery, light striking the photoelectrode causes the water to be photo-oxidized, thus charging the battery. During the discharge process, the solar water battery reduces oxygen to water with a high coulombic efficiency (>90%) and a high average output voltage (0.6 V). Because the reduction potential of oxygen is more positive [E(0) (O2/H2O) = 1.23 V vs. NHE] than common catholytes (e.g., iodide, sulfur), a high discharge voltage is produced. The solar water battery also exhibits a superior storage ability, maintaining 99% of its specific discharge capacitance after 10 h of storage, without any evidence of self-discharge. The optimization of the cell design and configuration, taking the presence of oxygen in the cell into account, was critical to achieving an efficient photocharge/discharge.

  7. Second life battery energy storage system for enhancing renewable energy grid integration

    DEFF Research Database (Denmark)

    Koch-Ciobotaru, C.; Saez-de-Ibarra, A.; Martinez-Laserna, E.;

    2015-01-01

    must be explored especially that large battery energy storage systems are still expensive solutions. Thus, in order to make battery investment economic viable, the use of second life batteries is investigated in the present work. This paper proposes a method for determining firstly, the optimal rating...... of a second life battery energy storage system (SLBESS) and secondly, to obtain the power exchange and battery state of charge profiles during the operation. These will constitute the cycling patterns for testing batteries and studying the ageing effect of this specific application. Real data from the Spanish...

  8. Rechargeable batteries applications handbook

    CERN Document Server

    1998-01-01

    Represents the first widely available compendium of the information needed by those design professionals responsible for using rechargeable batteries. This handbook introduces the most common forms of rechargeable batteries, including their history, the basic chemistry that governs their operation, and common design approaches. The introduction also exposes reader to common battery design terms and concepts.Two sections of the handbook provide performance information on two principal types of rechargeable batteries commonly found in consumer and industrial products: sealed nickel-cad

  9. Battery systems engineering

    CERN Document Server

    Rahn, Christopher D

    2012-01-01

    A complete all-in-one reference on the important interdisciplinary topic of Battery Systems Engineering Focusing on the interdisciplinary area of battery systems engineering, this book provides the background, models, solution techniques, and systems theory that are necessary for the development of advanced battery management systems. It covers the topic from the perspective of basic electrochemistry as well as systems engineering topics and provides a basis for battery modeling for system engineering of electric and hybrid electric vehicle platforms. This original

  10. Battery Review Board

    Science.gov (United States)

    Vaughn, Chester

    1993-01-01

    The topics covered are presented in viewgraph form: NASA Battery Review Board Charter; membership, board chronology; background; statement of problem; summary of problems with 50 AH standard Ni-Cd; activities for near term programs utilizing conventional Ni-Cd; present projects scheduled to use NASA standard Ni-Cd; other near-term NASA programs requiring secondary batteries; recommended direction for future programs; future cell/battery procurement strategy; and the NASA Battery Program.

  11. 用于提高风电场运行效益的电池储能配置优化模型%An Optimization Model of Battery Energy Storage System Configuration to Improve Benefits of Wind Farms

    Institute of Scientific and Technical Information of China (English)

    徐国栋; 程浩忠; 方斯顿; 马则良; 张建平; 朱忠烈

    2016-01-01

    More benefits can be earned for wind farms integrated with a battery energy storage system(BESS)by improving the acceptance of wind power.Firstly,this paper proposes a double optimization model for battery energy storage system considering grid structure. The optimal configuration node, power, capacity of BESS are determined with the aim of incremental benefits maximization for wind and storage joint system compared with wind farms only considering system security constraints in the outer planning model.The benefits maximization of wind and storage joint system is chosen as the objective function,and the output of generating units,wind farm,BESS as decision variables.In the constraints,power balance,spinning reserve, power and capacity of BESS are considered in the inner optimization model. A numerical optimization algorithm,which is based on an improved empirical competition algorithm is proposed to calculate the model. Finally,the validity of this model is verified in an improved IEEE 1 18-node system.Case results suggest that the best configuration of BESS can increase wind farm benefits,meanwhile both benefits increments and the improvement of abandoned wind show an increasing trend with reduction in investments or the increase in grid price.Furthermore,an appropriate initial capacity of BESS is able to improve the benefits of composite BESS and wind generation system.And on the premise of guaranteed convergence,the improved empirical competition algorithm can effectively increase the computing speed compared with the traditional one.%为风电场配置电池储能系统(BESS)可以有效提高风电接纳能力,增加风电场运行效益。首先,提出一种考虑网架结构的 BESS 配置双层优化模型。外层模型计及系统安全约束,以风储联合系统相较风电场单独运行的效益增加量最大化为目标,确定 BESS 最优配置节点、功率、容量;内层模型以风储联合运行效益最大化为目标,以

  12. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  13. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  14. Electric Vehicle Battery Challenge

    Science.gov (United States)

    Roman, Harry T.

    2014-01-01

    A serious drawback to electric vehicles [batteries only] is the idle time needed to recharge their batteries. In this challenge, students can develop ideas and concepts for battery change-out at automotive service stations. Such a capability would extend the range of electric vehicles.

  15. All-Vanadium Dual Circuit Redox Flow Battery for Renewable Hydrogen Generation and Desulfurisation

    OpenAIRE

    Peljo, Pekka Eero; Vrubel, Heron; Amstutz, Veronique; Pandard, Justine; Morgado, Joana; Santasalo-Aarnio, Annukka; Lloyd, David; Gumy, Frederic; Dennison, C R; Toghill, Kathryn; Girault, Hubert

    2016-01-01

    An all-vanadium dual circuit redox flow battery is an electrochemical energy storage system capable to function as a conventional battery, but also to produce hydrogen and perform desulfurization when surplus of electricity is available by chemical discharge of the battery electrolytes. The hydrogen reactor chemically discharging the negative electrolyte has been designed and scaled up to kW scale, while different options to discharge the positive electrolyte have been evaluated, including ox...

  16. Optimization of radial dimension and electricity cost for compact hybrid reactor%紧凑型混合堆径向几何尺寸与发电成本的优化

    Institute of Scientific and Technical Information of China (English)

    陈美霞; 刘成岳; 吴斌

    2011-01-01

    紧凑型聚变裂变混合堆是一种新的概念设计,文章通过改变聚变系统径向几何尺寸上的等离子体大小半径,分析了紧凑型聚变裂变混合堆的发电成本并进行优化,模拟结果表明紧凑型聚变裂变混合堆较传统的标准混合堆具有更大的经济优势.%Compact fusion-fission hybrid reactor(CFFHR) is a new kind of conceptual design. In this paper, the electricity cost of CFFHR is optimized by changing the radial dimensions of plasma major radius and minor radius of the fusion system. The simulation results show that the CFFHR is more economic than the traditional hybrid reactor.

  17. Battery Lifetime Analysis and Simulation Tool (BLAST) Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, J.

    2014-12-01

    The deployment and use of lithium-ion batteries in automotive and stationary energy storage applications must be optimized to justify their high up-front costs. Given that batteries degrade with use and storage, such optimizations must evaluate many years of operation. As the degradation mechanisms are sensitive to temperature, state-of-charge histories, current levels, and cycle depth and frequency, it is important to model both the battery and the application to a high level of detail to ensure battery response is accurately predicted. To address these issues, the National Renewable Energy Laboratory has developed the Battery Lifetime Analysis and Simulation Tool (BLAST) suite of tools. This suite of tools pairs NREL's high-fidelity battery degradation model with a battery electrical and thermal performance model, application-specific electrical and thermal performance models of the larger system (e.g., an electric vehicle), application-specific system use data (e.g., vehicle travel patterns and driving data), and historic climate data from cities across the United States. This provides highly realistic, long-term predictions of battery response and thereby enables quantitative comparisons of varied battery use strategies.

  18. Battery Lifetime Analysis and Simulation Tool (BLAST) Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-12-01

    The deployment and use of lithium-ion (Li-ion) batteries in automotive and stationary energy storage applications must be optimized to justify their high up-front costs. Given that batteries degrade with use and storage, such optimizations must evaluate many years of operation. As the degradation mechanisms are sensitive to temperature, state-of-charge (SOC) histories, current levels, and cycle depth and frequency, it is important to model both the battery and the application to a high level of detail to ensure battery response is accurately predicted. To address these issues, the National Renewable Energy Laboratory (NREL) has developed the Battery Lifetime Analysis and Simulation Tool (BLAST) suite. This suite of tools pairs NREL’s high-fidelity battery degradation model with a battery electrical and thermal performance model, application-specific electrical and thermal performance models of the larger system (e.g., an electric vehicle), application-specific system use data (e.g., vehicle travel patterns and driving data), and historic climate data from cities across the United States. This provides highly realistic long-term predictions of battery response and thereby enables quantitative comparisons of varied battery use strategies.

  19. Short-Term Active Power Optimization in Distribution Network with Battery Storage System%含电池储能系统的配电网短期有功优化

    Institute of Scientific and Technical Information of China (English)

    朱泽锋; 余一平

    2016-01-01

    将储能系统引入配电网中,参与配电网的调度计划,有利于提高分布式能源的利用效率和运行经济性。在对电池储能系统(battery storage system,BSS)建模的基础上,提出一种包含风机和BSS的配电网短期有功优化模型。考虑售购电价差异,实现了风电功率的最大化消纳、最小化配网购电成本;通过对BSS全寿命周期成本的考虑,对充放电切换次数进行限制,实现了BSS的经济运行。采用遗传算法和原对偶内点法结合的混合算法进行求解。通过对IEEE33节点标准算例进行测试,验证了所提模型及算法的有效性和可行性。%ABSTRACT:Energy storage systems have been introduced to distribution networks to participate in the active distribution network schedule,helping to improve the utilization efficiency and operating economy of distributed generations. In this paper, based on the modeling of battery storage system(BSS),a new model containing wind turbines and BSSis proposed to solve dynamic active power optimization in an active distribution network. Considering differences between the selling and pur-chasing prices,this model can maximize the accommodation capability of wind power and minimize the cost of electricity purchasing;and based on the consideration of the life cycle cost of the BSS,the switching times of charging and dischar-ging can be limited to realize the economical operation of the BBS. The mixed algorithm of genetic algorithm and interior point method is used to solve the problem. Numerical tests with the IEEE 33-bus system show that the proposed model and method are effective and feasible.

  20. Operation Strategy of EV Battery Charging and Swapping Station

    Institute of Scientific and Technical Information of China (English)

    Zhuo Peng; Li Zhang; Ku-An Lu; Jun-Peng Hu; Si Liu

    2014-01-01

    An operation strategy of the electric vehicle (EV) battery charging and swapping station is proposed in the paper. The strategy is established based on comprehensively consideration of the EV charging behaviors and the possible mutual actions between battery charging and swapping. Three energy management strategies can be used in the station:charging period shifting, energy exchange between EVs, and energy supporting from surplus swapping batteries. Then an optimization model which minimizes the total energy management costs of the station is built. The Monte Carlo simulation is applied to analyze the characteristics of the EV battery charging load, and a heuristic algorithm is used to solve the strategy providing the relevant information of EVs and the battery charging and swapping station. The operation strategy can efficiently reduce battery charging during the high electricity price periods and make more reasonable use of the resources. Simulations prove the feasibility and rationality of the strategy.

  1. Optimal Planning and Design of a Wind/Biomass/Diesel/Battery Stand-alone Microgrid%风柴储生物质独立微电网系统的优化规划设计

    Institute of Scientific and Technical Information of China (English)

    周志超; 郭力; 王成山; 焦冰琦; 许伟; 葛磊蛟

    2014-01-01

    Based on the analysis of the existing power system,load demand and natural resources in a remote aboriginal community,a wind/biomass/diesel/battery stand-alone microgrid (SAMG) is proposed to replace the current diesel engine (DE) system.According to the operating characteristics of these distributed generators (DGs),an improved load following (ILF) control strategy is presented to improve the renewable energy penetration and decrease the diesel consumption remarkably,and also to optimize the capacity size and operation conditions of the battery energy storage system (BESS).This ILF strategy uses DE and biomass plant to follow the net load variations at different time scales respectively,and the BESS mainly help to keep the system stabilization.The non-dominated sorting genetic algorithm (NSGA-Ⅱ) is adopted to solve the multi-objective optimization model considering the net present cost(NPC)and the pollutant emission level in the 20 years full life cycle.The results validate the effectiveness of the proposed method,and show that the proposed solution is reasonable and feasible,meeting diverse demands,as an optimization solution.%对某偏远原住民社区现有供电系统、负荷及自然资源情况进行了分析统计,提出一种包含风柴储生物质的独立微电网解决方案,以替换现有的柴油供电系统。根据各分布式电源的技术特性,提出一种改进型负荷跟随控制策略,以柴油发电机组和生物质发电系统分别跟随系统内不同时间尺度下的净负荷波动,储能系统主要起系统稳定控制作用,可显著提高可再生能源渗透率,减少柴油消耗量,并能优化储能系统的容量配置和运行工况。以系统20年寿命周期净现值费用与污染物排放最小为优化目标,采用改进型非劣排序遗传算法(NSGA-Ⅱ),开展了系统方案的综合优化设计,结果表明了优化设计方案的可行性。

  2. Optimization for structure of internal loop fluidized bed reactor based on computational fluid dynamics%基于CFD的养殖污水净化内循环流化床反应器结构优化

    Institute of Scientific and Technical Information of China (English)

    李源; 杨菁; 管崇武; 宋红桥; 吴凡; 张成林; 陈晓龙

    2014-01-01

    针对水产养殖污水净化对内循环流化床反应器的相关要求及流化状态下反应器结构、操作参数与相流体力学行为的密切关系,该文利用构建的描述不同结构、操作参数反应器气液两相流动的计算流体力学数学模型,分析了不同结构、操作参数下反应器液体流场、液体循环流量、气含率的变化规律,得到了对于内径200 mm、底部采用均孔布气盘的反应器,在表观气速为0.5~2.5 cm/s时,导流筒与反应器的内径比0.5,导流筒高度与反应器内径比6,导流筒下端到反应器底部距离50 mm,导流筒上端到液面距离100 mm为最优值;针对液体循环流量,使用相关数学模型求解理论值并与试验值进行比对,通过偏差分析探究了数学模型应用的局限性;使用MATLAB最小二乘法拟合了反应器在最优结构参数下表观气速与液体循环流量、气含率的关系,验证了拟合公式的精确性。该研究为内循环流化床反应器在水产养殖污水处理中的设计应用提供理论和技术参考。%Internal loop fluidized bed reactor is a kind of advanced bioreactor in the field of biological sewage treatment, its fluidization working principle speeds up biochemical reactions in the reactor, it has great significance on the efficient cleaning of aquaculture wastewater. However, the reactor performance under working conditions is closely related to its internal phase fluid mechanics behavior, the complex relationship exists among fluid mechanics behavior of phase, reactor structure parameters and operating parameters, aquaculture water disposal requirements are different to other relevant fields, which make reactor design and optimization difficult. Based on the Eulerian-Eulerian model, this article selected the diameter ratio of draft tube and the reactor, ratio of draft tube height and reactor diameter, height of the gas-liquid mixture region, height of the gas

  3. Alkaline quinone flow battery.

    Science.gov (United States)

    Lin, Kaixiang; Chen, Qing; Gerhardt, Michael R; Tong, Liuchuan; Kim, Sang Bok; Eisenach, Louise; Valle, Alvaro W; Hardee, David; Gordon, Roy G; Aziz, Michael J; Marshak, Michael P

    2015-09-25

    Storage of photovoltaic and wind electricity in batteries could solve the mismatch problem between the intermittent supply of these renewable resources and variable demand. Flow batteries permit more economical long-duration discharge than solid-electrode batteries by using liquid electrolytes stored outside of the battery. We report an alkaline flow battery based on redox-active organic molecules that are composed entirely of Earth-abundant elements and are nontoxic, nonflammable, and safe for use in residential and commercial environments. The battery operates efficiently with high power density near room temperature. These results demonstrate the stability and performance of redox-active organic molecules in alkaline flow batteries, potentially enabling cost-effective stationary storage of renewable energy. PMID:26404834

  4. Detection of antineutrinos for reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeong Duk [Center for Underground Physics, Institute of Basic Science, Daejeon (Korea, Republic of)

    2016-04-15

    Reactor neutrinos have been detected in the past 50 years by various detectors for different purposes. Beginning in the 1980s, neutrino physicists have tried to use neutrinos to monitor reactors and develop an optimized detector for nuclear safeguards. Recently, motivated by neutrino oscillation physics, the technology and scale of reactor neutrino detection have progressed considerably. In this review, I will give an overview of the detection technology for reactor neutrinos, and describe the issues related to further improvements in optimized detectors for reactor monitoring.

  5. 29 CFR 1926.441 - Batteries and battery charging.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Batteries and battery charging. 1926.441 Section 1926.441... for Special Equipment § 1926.441 Batteries and battery charging. (a) General requirements—(1... areas. (2) Ventilation shall be provided to ensure diffusion of the gases from the battery and...

  6. Research reactors

    International Nuclear Information System (INIS)

    This article proposes an overview of research reactors, i.e. nuclear reactors of less than 100 MW. Generally, these reactors are used as neutron generators for basic research in matter sciences and for technological research as a support to power reactors. The author proposes an overview of the general design of research reactors in terms of core size, of number of fissions, of neutron flow, of neutron space distribution. He outlines that this design is a compromise between a compact enough core, a sufficient experiment volume, and high enough power densities without affecting neutron performance or its experimental use. The author evokes the safety framework (same regulations as for power reactors, more constraining measures after Fukushima, international bodies). He presents the main characteristics and operation of the two families which represent almost all research reactors; firstly, heavy water reactors (photos, drawings and figures illustrate different examples); and secondly light water moderated and cooled reactors with a distinction between open core pool reactors like Melusine and Triton, pool reactors with containment, experimental fast breeder reactors (Rapsodie, the Russian BOR 60, the Chinese CEFR). The author describes the main uses of research reactors: basic research, applied and technological research, safety tests, production of radio-isotopes for medicine and industry, analysis of elements present under the form of traces at very low concentrations, non destructive testing, doping of silicon mono-crystalline ingots. The author then discusses the relationship between research reactors and non proliferation, and finally evokes perspectives (decrease of the number of research reactors in the world, the Jules Horowitz project)

  7. Reactor physics and reactor computations

    International Nuclear Information System (INIS)

    Mathematical methods and computer calculations for nuclear and thermonuclear reactor kinetics, reactor physics, neutron transport theory, core lattice parameters, waste treatment by transmutation, breeding, nuclear and thermonuclear fuels are the main interests of the conference

  8. Electrochemical accumulators batteries; Accumulateurs electrochimiques batteries

    Energy Technology Data Exchange (ETDEWEB)

    Ansart, F.; Castillo, S.; Laberty- Robert, C.; Pellizon-Birelli, M. [Universite Paul Sabatier, Lab. de Chimie des Materiaux Inorganiques et Energetiques, CIRIMAT, UMR CNRS 5085, 31 - Toulouse (France)] [and others

    2000-07-01

    It is necessary to storage the electric power in batteries to join the production and the utilization. In this domain progresses are done every days in the technics and also in the available materials. These technical days present the state of the art in this domain. Many papers were presented during these two days giving the research programs and recent results on the following subjects: the lithium batteries, the electrolytes performances and behaviour, lead accumulators, economic analysis of the electrochemical storage market, the batteries applied to the transportation sector and the telephones. (A.L.B.)

  9. Study on the Laying Scheme of Solar Photovoltaic Battery Optimal%太阳能光伏电池最优铺设方案研究

    Institute of Scientific and Technical Information of China (English)

    李揭阳; 贾薇玮; 王艳丽

    2014-01-01

    According to the different types of PV market price ,power efficiency and the Shanxi prov-ince Datong typical meteorological data ,we integrated solar radiation intensity and the angle of incidence of the light and the building locates the geographical latitude and other factors ,then we built the model of multi -objective linear programming ,finally ,we further optimized the housing surface photovoltaic cells .%根据市场上不同种类光伏电池的价格、发电效率等性能,采用山西省大同市典型气象数据,综合参考当地的太阳辐射强度、光线入射角以及建筑物所处地理纬度等因素,建立了多目标决策模型和线性规划模型,并通过进一步优化得出房屋表面光伏电池的最优设计方案。

  10. Progress in Modeling and Simulation of Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Turner, John A [ORNL

    2016-01-01

    Modeling and simulation of batteries, in conjunction with theory and experiment, are important research tools that offer opportunities for advancement of technologies that are critical to electric motors. The development of data from the application of these tools can provide the basis for managerial and technical decision-making. Together, these will continue to transform batteries for electric vehicles. This collection of nine papers presents the modeling and simulation of batteries and the continuing contribution being made to this impressive progress, including topics that cover: * Thermal behavior and characteristics * Battery management system design and analysis * Moderately high-fidelity 3D capabilities * Optimization Techniques and Durability As electric vehicles continue to gain interest from manufacturers and consumers alike, improvements in economy and affordability, as well as adoption of alternative fuel sources to meet government mandates are driving battery research and development. Progress in modeling and simulation will continue to contribute to battery improvements that deliver increased power, energy storage, and durability to further enhance the appeal of electric vehicles.

  11. Electric-vehicle batteries

    Science.gov (United States)

    Oman, Henry; Gross, Sid

    1995-02-01

    Electric vehicles that can't reach trolley wires need batteries. In the early 1900's electric cars disappeared when owners found that replacing the car's worn-out lead-acid battery costs more than a new gasoline-powered car. Most of today's electric cars are still propelled by lead-acid batteries. General Motors in their prototype Impact, for example, used starting-lighting-ignition batteries, which deliver lots of power for demonstrations, but have a life of less than 100 deep discharges. Now promising alternative technology has challenged the world-wide lead miners, refiners, and battery makers into forming a consortium that sponsors research into making better lead-acid batteries. Horizon's new bipolar battery delivered 50 watt-hours per kg (Wh/kg), compared with 20 for ordinary transport-vehicle batteries. The alternatives are delivering from 80 Wh/kg (nickel-metal hydride) up to 200 Wh/kg (zinc-bromine). A Fiat Panda traveled 260 km on a single charge of its zinc-bromine battery. A German 3.5-ton postal truck traveled 300 km with a single charge in its 650-kg (146 Wh/kg) zinc-air battery. Its top speed was 110 km per hour.

  12. Lifetime Improvement by Battery Scheduling

    NARCIS (Netherlands)

    Jongerden, Marijn R.; Haverkort, Boudewijn R.; Schmitt, Jens B.

    2012-01-01

    The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to

  13. Lifetime improvement by battery scheduling

    NARCIS (Netherlands)

    Jongerden, Marijn R.; Haverkort, Boudewijn R.

    2011-01-01

    The use of mobile devices is often limited by the lifetime of its battery. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to t

  14. Solar-rechargeable battery based on photoelectrochemical water oxidation: Solar water battery

    Science.gov (United States)

    Kim, Gonu; Oh, Misol; Park, Yiseul

    2016-09-01

    As an alternative to the photoelectrochemical water splitting for use in the fuel cells used to generate electrical power, this study set out to develop a solar energy rechargeable battery system based on photoelectrochemical water oxidation. We refer to this design as a “solar water battery”. The solar water battery integrates a photoelectrochemical cell and battery into a single device. It uses a water oxidation reaction to simultaneously convert and store solar energy. With the solar water battery, light striking the photoelectrode causes the water to be photo-oxidized, thus charging the battery. During the discharge process, the solar water battery reduces oxygen to water with a high coulombic efficiency (>90%) and a high average output voltage (0.6 V). Because the reduction potential of oxygen is more positive [E0 (O2/H2O) = 1.23 V vs. NHE] than common catholytes (e.g., iodide, sulfur), a high discharge voltage is produced. The solar water battery also exhibits a superior storage ability, maintaining 99% of its specific discharge capacitance after 10 h of storage, without any evidence of self-discharge. The optimization of the cell design and configuration, taking the presence of oxygen in the cell into account, was critical to achieving an efficient photocharge/discharge.

  15. Battery Sizing for Plug-in Hybrid Electric Vehicles in Beijing: A TCO Model Based Analysis

    OpenAIRE

    Cong Hou; Hewu Wang; Minggao Ouyang

    2014-01-01

    This paper proposes a total cost of ownership (TCO) model for battery sizing of plug-in hybrid electric vehicles (PHEVs). The proposed systematic TCO model innovatively integrates the Beijing driving database and optimal PHEV energy management strategies developed earlier. The TCO, including battery, fuel, electricity, and salvage costs, is calculated in yearly cash flows. The salvage cost, based on battery degradation model, is proposed for the first time. The results show that the optimal b...

  16. WWER型核电机组反应堆停堆保护系统设计优化与改造%Design Optimization and Modification of Reactor Trip Protection System of Nuclear Power Unit of WWER

    Institute of Scientific and Technical Information of China (English)

    李伟; 袁屹昆; 徐霞军; 苑伟宇

    2011-01-01

    When carrying out periodic test of nuclear power unit reactor trip protection system, it is necessary to disconnect trip breakers in turn. There are big risks in such kind of periodic tests and many unplanned trip e-vents happened because of malfunction of equipment in reactor trip protection system periodic tests of foreign and domestic nuclear power units under operation, which caused great economic loss. The paper introduces the practical results of design optimization and modification of reactor trip protection system of a nuclear power unit of WWER.%在进行核电机组反应堆停堆保护系统定期试验时,需依次将停堆断路器实体断开,此类定期试验风险较大,国内外运行的核电机组多次发生在反应堆停堆保护系统定期试验过程中由于设备故障导致非计划停堆的事件,造成了较大的经济损失.论文介绍了某WWER核电机组反应堆停堆保护系统设计优化方案及改造的实践成果.

  17. The problem of optimizing the water chemistry used in the primary coolant circuit of a nuclear power station equipped with VVER reactors under the conditions of longer fuel cycle campaigns and increased capacity of power units

    Science.gov (United States)

    Sharafutdinov, R. B.; Kharitonova, N. L.

    2011-05-01

    It is shown that the optimal water chemistry of the primary coolant circuit must be substantiated while introducing measures aimed at increasing the power output in operating power units and for the project called AES-2006/AES TOI (a typical optimized project of a nuclear power station with enhanced information support). The experience gained from operation of PWR reactors with an elongated fuel cycle at an increased level of power is analyzed. Conditions under which boron compounds are locally concentrated on the fuel rod surfaces (the hideout phenomenon) and axial offset anomaly occurs are enlisted, and the influence of lithium on the hideout in the pores of deposits on the surfaces of fuel assemblies is shown.

  18. Optimized conditions for glycine-nitrate-based solution combustion synthesis of LiNi0.5Mn1.5O4 as a high-voltage cathode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • LiNi0.5Mn1.5O4 were produced by glycine-nitrate solution combustion synthesis. • Optimized production conditions were studied. • Electrochemical performance was characterized by galvanostatic charge-discharge cycling. • Product obtained at G/N ratio of 1 and calcined at 800 °C for 24 h showed best performance. • The sample showed an initial capacity of 124.9 mAh/g and retained 97.20% after 50 cycles at 1 C rate. - Abstract: This paper describes the glycine-nitrate-based solution combustion synthesis of LiNi0.5Mn1.5O4 as a high-voltage cathode material for lithium-ion batteries. The morphology, size, and crystallinity of the products were dependent on the synthesis conditions like glycine amount and calcination temperature and duration, as investigated in particular by X-ray diffraction and scanning electron microscopy, which likewise influenced their electrochemical properties. The electrochemical performance was characterized by galvanostatic charge-discharge cycling. The product obtained at a glycine/nitrate ratio of 1, which was calcined at 800 °C for 24 h, indicated the best charge-discharge cycling performance. The sample showed an initial discharge capacity of 124.9 mAh/g and could retained 97.20% of the capacity after 50 cycles at a charge-discharge rate of 1 C. The sample also exhibited a good high-rate capability, indicating a high discharge capacity of 98 mAh/g at a rate of 10 C

  19. Lead-nickel electrochemical batteries

    CERN Document Server

    Glaize, Christian

    2012-01-01

    The lead-acid accumulator was introduced in the middle of the 19th Century, the diverse variants of nickel accumulators between the beginning and the end of the 20th Century. Although old, these technologies are always very present on numerous markets. Unfortunately they are still not used in optimal conditions, often because of the misunderstanding of the internal electrochemical phenomena.This book will show that batteries are complex systems, made commercially available thanks to considerable amounts of scientific research, empiricism and practical knowledge. However, the design of

  20. Grace DAKASEP alkaline battery separator

    Science.gov (United States)

    Giovannoni, R. T.; Lundquist, J. T.; Choi, W. M.

    1987-01-01

    The Grace DAKASEP separator was originally developed as a wicking layer for nickel-zinc alkaline batteries. The DAKASEP is a filled non-woven separator which is flexible and heat sealable. Through modification of formulation and processing variables, products with a variety of properties can be produced. Variations of DAKASEP were tested in Ni-H2, Ni-Zn, Ni-Cd, and primary alkaline batteries with good results. The properties of DAKASEP which are optimized for Hg-Zn primary batteries are shown in tabular form. This separator has high tensile strength, 12 micron average pore size, relatively low porosity at 46-48 percent, and consequently moderately high resistivity. Versions were produced with greater than 70 percent porosity and resistivities in 33 wt percent KOH as low as 3 ohm cm. Performance data for Hg-Zn E-1 size cells containing DAKASEP with the properties shown in tabular form, are more reproducible than data obtained with a competitive polypropylene non-woven separator. In addition, utilization of active material is in general considerably improved.

  1. A Desalination Battery

    KAUST Repository

    Pasta, Mauro

    2012-02-08

    Water desalination is an important approach to provide fresh water around the world, although its high energy consumption, and thus high cost, call for new, efficient technology. Here, we demonstrate the novel concept of a "desalination battery", which operates by performing cycles in reverse on our previously reported mixing entropy battery. Rather than generating electricity from salinity differences, as in mixing entropy batteries, desalination batteries use an electrical energy input to extract sodium and chloride ions from seawater and to generate fresh water. The desalination battery is comprised by a Na 2-xMn 5O 10 nanorod positive electrode and Ag/AgCl negative electrode. Here, we demonstrate an energy consumption of 0.29 Wh l -1 for the removal of 25% salt using this novel desalination battery, which is promising when compared to reverse osmosis (∼ 0.2 Wh l -1), the most efficient technique presently available. © 2012 American Chemical Society.

  2. Lithium ion battery production

    International Nuclear Information System (INIS)

    Highlights: ► Sustainable battery manufacturing focus on more efficient methods and recycling. ► Temperature control and battery management system increase battery lifetime. ► Focus on increasing battery performance at low- and high temperatures. ► Production capacity of 100 MWh equals the need of 3000 full-electric cars. - Abstract: Recently, new materials and chemistry for lithium ion batteries have been developed. There is a great emphasis on electrification in the transport sector replacing part of motor powered engines with battery powered applications. There are plans both to increase energy efficiency and to reduce the overall need for consumption of non-renewable liquid fuels. Even more significant applications are dependent on energy storage. Materials needed for battery applications require specially made high quality products. Diminishing amounts of easily minable metal ores increase the consumption of separation and purification energy and chemicals. The metals are likely to be increasingly difficult to process. Iron, manganese, lead, zinc, lithium, aluminium, and nickel are still relatively abundant but many metals like cobalt and rare earths are becoming limited resources more rapidly. The global capacity of industrial-scale production of larger lithium ion battery cells may become a limiting factor in the near future if plans for even partial electrification of vehicles or energy storage visions are realized. The energy capacity needed is huge and one has to be reminded that in terms of cars for example production of 100 MWh equals the need of 3000 full-electric cars. Consequently annual production capacity of 106 cars requires 100 factories each with a 300 MWh capacity. Present day lithium ion batteries have limitations but significant improvements have been achieved recently . The main challenges of lithium ion batteries are related to material deterioration, operating temperatures, energy and power output, and lifetime. Increased lifetime

  3. Lithium battery management system

    Science.gov (United States)

    Dougherty, Thomas J.

    2012-05-08

    Provided is a system for managing a lithium battery system having a plurality of cells. The battery system comprises a variable-resistance element electrically connected to a cell and located proximate a portion of the cell; and a device for determining, utilizing the variable-resistance element, whether the temperature of the cell has exceeded a predetermined threshold. A method of managing the temperature of a lithium battery system is also included.

  4. Polyoxometalate flow battery

    Science.gov (United States)

    Anderson, Travis M.; Pratt, Harry D.

    2016-03-15

    Flow batteries including an electrolyte of a polyoxometalate material are disclosed herein. In a general embodiment, the flow battery includes an electrochemical cell including an anode portion, a cathode portion and a separator disposed between the anode portion and the cathode portion. Each of the anode portion and the cathode portion comprises a polyoxometalate material. The flow battery further includes an anode electrode disposed in the anode portion and a cathode electrode disposed in the cathode portion.

  5. Nanotubes for Battery Applications

    OpenAIRE

    Nordlinder, Sara

    2005-01-01

    Nanomaterials have attracted great interest in recent years, and are now also being considered for battery applications. Reducing the particle size of some electrode materials can increase battery performance considerably, especially with regard to capacity, power and rate capability. This thesis presents a study focused on the performance of such a material, vanadium oxide nanotubes, as cathode material for rechargeable lithium batteries. These nanotubes were synthesized by a sol-gel process...

  6. Battery Thermal Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, Matthew; Saxon, Aron; Powell, Mitchell; Shi, Ying

    2016-06-07

    This poster shows the progress in battery thermal characterization over the previous year. NREL collaborated with U.S. DRIVE and USABC battery developers to obtain thermal properties of their batteries, obtained heat capacity and heat generation of cells under various power profiles, obtained thermal images of the cells under various drive cycles, and used the measured results to validate thermal models. Thermal properties are used for the thermal analysis and design of improved battery thermal management systems to support achieve life and performance targets.

  7. The maximum work output of an electric battery in a given time

    Energy Technology Data Exchange (ETDEWEB)

    Jincan Chen; Zheqiang Shi [Xiamen Univ., Dept. of Physics, Xiamen (China); Xuyang Chen [Center of Television Transmission, Xiamen (China)

    2002-10-01

    A new model of an electric battery is established, based on the simplest battery model and Denno's battery model with an internal dissipation. The model is used to investigate the fundamental problem of how to maximize the work output of an electric battery in a given time. The important relation of the voltage across the battery terminals varying with the discharging time is derived by using variational calculus. The maximum work output of the battery is calculated. The optimal matching condition of the load resistance is determined. The reasonable range of the discharging time is given. The other characteristics of the battery at the maximum work output are discussed further. The results obtained here have some theoretical applications not only for raising the utilization of the electric energy stored in batteries, but also for improving the performance of some electric circuits. (Author)

  8. Performance requirements of automotive batteries for future car electrical systems

    Science.gov (United States)

    Friedrich, R.; Richter, G.

    The further increase in the number of power-consuming functions which has been announced for future vehicle electrical systems, and in particular the effects of new starting systems on battery performance, requires a further optimization of the lead acid system coupled with effective energy management, and enhanced battery operating conditions. In the face of these increased requirements, there are proven benefits to splitting the functions of a single SLI battery between two separate, special-purpose batteries, each of which are optimized, for high power output and for high energy throughput, respectively. This will bring about a marked improvement in weight, reliability, and state of charge (SOC). The development of special design starter and service batteries is almost completed and will lead to new products with a high standard of reliability. The design of the power-optimized lead acid accumulator is particularly suitable for further development as the battery for a 42/36 V electrical system. This is intended to improve the efficiency of the generator and the various power-consuming functions and to improve start/stop operation thereby bringing about a marked reduction in the fuel consumption of passenger cars. This improvement can also be assisted by a charge management system used in conjunction with battery status monitoring.

  9. Reactor building

    International Nuclear Information System (INIS)

    The whole reactor building is accommodated in a shaft and is sealed level with the earth's surface by a building ceiling, which provides protection against penetration due to external effects. The building ceiling is supported on walls of the reactor building, which line the shaft and transfer the vertical components of forces to the foundations. The thickness of the walls is designed to withstand horizontal pressure waves in the floor. The building ceiling has an opening above the reactor, which must be closed by cover plates. Operating equipment for the reactor can be situated above the building ceiling. (orig./HP)

  10. Development, process optimization and technical realization of a novel technology for the treatment of contaminated soil based on the microbiological reactor technique by means of system analysis

    International Nuclear Information System (INIS)

    The aim of this work was to develop a biological procedure to clean up contaminated soil using a technique based on microbiological fermentation, and to implement it for large-scale utilization. As a first step, the current procedures for the subsequent application were put into practice. The advantages and disadvantages, as well as the most sensible field of application were ascertained and contrasted. The ecological and economical prerequisites and demands on the new technology resulted from these investigations. Starting from cleaning up contaminated soil in controlled fermenters (bio-reactors) with the help of the appropriate mixed populations of aerobic bacteria, the development of the technical procedures and the guarantee as to their cost effectiveness is of foremost importance. The technical procedure of the whole concept was developed on a semicommercial scale step by step from the findings of laboratory trials and experiments. The whole concept contains the following procedural steps: 1 Preparation of the soil: 2 Mechanical disintegration using water: The soil is lead to a drum mixer by means of a conveyor device and turned into mud using water. 3 Wet-sizing: In the next step, sand and gravel are separated from very fine particles (grain sized < 0.5mm) and the wash water in a special vibrating sieve device. 4 Bio-reactor: The contaminated soil suspension, which contains all the harmful substances, is lead to the bio-reactor where, with the help of an enriched aerobic bacterial population, the contaminants are biologically degraded. A complete breakdown of the contaminants is achieved after 15 -20 hours in the reactor. 5 Drainage: Subsequently, the soil suspension is drained into a special sedimentation tank. (author)

  11. Innovative and Advanced Coupled Neutron Transport and Thermal Hydraulic Method (Tool) for the Design, Analysis and Optimization of VHTR/NGNP Prismatic Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rahnema, Farzad; Garimeela, Srinivas; Ougouag, Abderrafi; Zhang, Dingkang

    2013-11-29

    This project will develop a 3D, advanced coarse mesh transport method (COMET-Hex) for steady- state and transient analyses in advanced very high-temperature reactors (VHTRs). The project will lead to a coupled neutronics and thermal hydraulic (T/H) core simulation tool with fuel depletion capability. The computational tool will be developed in hexagonal geometry, based solely on transport theory without (spatial) homogenization in complicated 3D geometries. In addition to the hexagonal geometry extension, collaborators will concurrently develop three additional capabilities to increase the code’s versatility as an advanced and robust core simulator for VHTRs. First, the project team will develop and implement a depletion method within the core simulator. Second, the team will develop an elementary (proof-of-concept) 1D time-dependent transport method for efficient transient analyses. The third capability will be a thermal hydraulic method coupled to the neutronics transport module for VHTRs. Current advancements in reactor core design are pushing VHTRs toward greater core and fuel heterogeneity to pursue higher burn-ups, efficiently transmute used fuel, maximize energy production, and improve plant economics and safety. As a result, an accurate and efficient neutron transport, with capabilities to treat heterogeneous burnable poison effects, is highly desirable for predicting VHTR neutronics performance. This research project’s primary objective is to advance the state of the art for reactor analysis.

  12. Spatiotemporal modeling of internal states distribution for lithium-ion battery

    Science.gov (United States)

    Wang, Mingliang; Li, Han-Xiong

    2016-01-01

    Electrochemical properties of the battery are described in partial differential equations that are impossible to compute online. These internal states are spatially distributed and thus difficult to measure in the battery operation. A space-time separation method is applied to model the electrochemical properties of the battery with the help of the extended Kalman filter. The model is efficiently optimized by using LASSO adaptation method and can be updated through data-based learning. The analytical model derived is able to offer a fast estimation of internal states of the battery, and thus has potential to become a prediction model for battery management system.

  13. Proposal of Space Reactor for Nuclear Electric Propulsion System

    Science.gov (United States)

    Nagata, Hidetaka; Nishiyama, Takaaki; Nakashima, Hideki

    Currently, the solar battery, the chemical cell, and the RI battery are used for the energy source in space. However, it is difficult for them to satisfy requirements for deep space explorations. Therefore, other electric power sources which can stably produce high electric energy output, regardless of distance from the sun, are necessary to execute such missions. Then, we here propose small nuclear reactors as power sources for deep space exploration, and consider a conceptual design of a small nuclear reactor for Nuclear Electric Propulsion System. It is found from nuclear analyses that the Gas-Cooled reactor could not meet the design requirement imposed on the core mass. On the other hand, a light water reactor is found to be a promising alternative to the Gas-Cooled reactor.

  14. Effects of generation and optimization of libraries of effective sections in the analysis of transient in PWR reactors; Efectos de generacion y optimizacion de librerias de secciones eficaces en el analisis de transitorios en reactores PWR

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Cervera, S.; Garcia Herranz, N.; Cuervo, D.; Ahnert, C.

    2014-07-01

    In this paper evaluates the impact that has a certain mesh on a transient in a PWR reactor in the expulsion of a control bar. Have been used for this purpose the coupled codes neutronic and Thermo-hydraulic COBAYA3/COBRA-TF. This objective has been chosen the OECD/NEA PWR MOX/UO{sub 2} rod ejection transient benchmark provides isotopic compositions and defined geometric configurations that allow the use of codes lattice to generate own bookstores. The code used for this transport has been the code APOLLO2.8. The results show large discrepancies when using the benchmark library or libraries own by comparing them to the other participants solutions. The source of these discrepancies is the nodal effective sections provided in the benchmark. (Author)

  15. Battery energy storage system

    NARCIS (Netherlands)

    Tol, C.S.P.; Evenblij, B.H.

    2009-01-01

    The ability to store electrical energy adds several interesting features to a ships distribution network, as silent power, peak shaving and a ride through in case of generator failure. Modern intrinsically safe Li-ion batteries bring these within reach. For this modern lithium battery applications t

  16. Batteries: Charging ahead rationally

    Science.gov (United States)

    Freunberger, Stefan A.

    2016-06-01

    Redox mediators facilitate the oxidation of the highly insulating discharge product in metal–oxygen batteries during recharge and offer opportunities to achieve high reversible capacities. Now a design principle for selecting redox mediators that can recharge the batteries more efficiently is suggested.

  17. Computing Battery Lifetime Distributions

    NARCIS (Netherlands)

    Cloth, Lucia; Jongerden, Marijn R.; Haverkort, Boudewijn R.

    2007-01-01

    The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetime depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a

  18. Hydrophobic, Porous Battery Boxes

    Science.gov (United States)

    Bragg, Bobby J.; Casey, John E., Jr.

    1995-01-01

    Boxes made of porous, hydrophobic polymers developed to contain aqueous potassium hydroxide electrolyte solutions of zinc/air batteries while allowing air to diffuse in as needed for operation. Used on other types of batteries for in-cabin use in which electrolytes aqueous and from which gases generated during operation must be vented without allowing electrolytes to leak out.

  19. Minimizing heat loss in DC networks using batteries

    CERN Document Server

    Zocca, Alessandro

    2016-01-01

    Electricity transmission networks dissipate a non-negligible fraction of the power they transport due to the heat loss in the transmission lines. In this work we explore how the transport of energy can be more efficient by adding to the network multiple batteries that can coordinate their operations. Such batteries can both charge using the current excess in the network or discharge to meet the network current demand. Either way, the presence of batteries in the network can be leveraged to mitigate the intrinsic uncertainty in the power generation and demand and, hence, transport the energy more efficiently through the network. We consider a resistive DC network with stochastic external current injections or consumptions and show how the expected total heat loss depends on the network structure and on the batteries operations. Furthermore, in the case where the external currents are modeled by Ornstein-Uhlenbeck processes, we derive the dynamical optimal control for the batteries over a finite time interval.

  20. Flexible fiber batteries for applications in smart textiles

    International Nuclear Information System (INIS)

    In this paper, we demonstrate flexible fiber-based Al–NaOCl galvanic cells fabricated using fiber drawing process. Aluminum and copper wires are used as electrodes, and they are introduced into the fiber structure during drawing of the low-density polyethylene microstructured jacket. NaOCl solution is used as electrolyte, and it is introduced into the battery after the drawing process. The capacity of a 1 m long fiber battery is measured to be ∼10 mAh. We also detail assembly and optimization of the electrical circuitry in the energy-storing fiber battery textiles. Several examples of their applications are presented including lighting up an LED, driving a wireless mouse and actuating a screen with an integrated shape-memory nitinol wire. The principal advantages of the presented fiber batteries include: ease of fabrication, high flexibility, simple electrochemistry and use of widely available materials in the battery design. (paper)

  1. Flexible fiber batteries for applications in smart textiles

    Science.gov (United States)

    Qu, Hang; Semenikhin, Oleg; Skorobogatiy, Maksim

    2015-02-01

    In this paper, we demonstrate flexible fiber-based Al-NaOCl galvanic cells fabricated using fiber drawing process. Aluminum and copper wires are used as electrodes, and they are introduced into the fiber structure during drawing of the low-density polyethylene microstructured jacket. NaOCl solution is used as electrolyte, and it is introduced into the battery after the drawing process. The capacity of a 1 m long fiber battery is measured to be ˜10 mAh. We also detail assembly and optimization of the electrical circuitry in the energy-storing fiber battery textiles. Several examples of their applications are presented including lighting up an LED, driving a wireless mouse and actuating a screen with an integrated shape-memory nitinol wire. The principal advantages of the presented fiber batteries include: ease of fabrication, high flexibility, simple electrochemistry and use of widely available materials in the battery design.

  2. Operating experiences of the research reactors

    International Nuclear Information System (INIS)

    Nuclear research reactors are devices of wide importance, being used for different scientific research tasks, for testing and improving reactor systems and components, for the production of radioisotopes, for the purposes of defence, for staff training and for other purposes. There are three research reactors in Yugoslavia: RA, RB and TRIGA. Reactors RA and RB at the 'Boris Kidric' Institute of Nuclear Sciences are of heavy water type power being 6500 and 10 kW, and maximum thermal neutron flux of 1014 and 1011(n/cm2s), respectively. TRIGA reactor at the 'Jozef Stefan' Institute in Ljubljana is of 250 kW power and maximum thermal neutron flux of 1013(n/cm2s). Reactors RA and RB use soviet fuel in the form of uranium dioxide (80% enriched) and metallic uranium (2%). Besides, RB reactor operates with natural uranium too. TRIGA reactor uses american uranium fuel 70% and 20% enriched, uranium being mixed homogeneously with moderator (ZrH). Experiences in handling and controlling the fuel before irradiation in the reactor, in reactor and after it are numerous and valuable, involving either the commercial arrangements with foreign producers, or optimal burn up in reactor or fuel treatment after the reactor irradiation. Twenty years of operating experience of these reactors have great importance especially having in mind the number of trained staff. Maintenance of reactors systems and fluids in continuous operation is valuable experience from the point of view of water reactor utilization. The case of the RA reactor primary cycle cobalt decontamination and other events connected with nuclear and radiation security for all three reactors are also specially emphasized. Owing to our research reactors, numerous theoretical, numerical and experimental methods are developed for nuclear and other analyses and design of research and power reactors,as well as methods for control and protection of radiation. (author)

  3. PIC BASED SOLAR CHARGING CONTROLLER FOR BATTERY

    Directory of Open Access Journals (Sweden)

    Mrs Jaya N. Ingole

    2012-02-01

    Full Text Available Solar resource is unlimited the government is trying to implement the use of Solar panels as an energy source in rural and sub urban areas for lighting the street lights, but the battery used to store the power gets affected due to overcharge & discharges. This paper presents the use of PIC16F72 based solar charger controller for controlling the overcharging and discharging of a solar cell. It works by continuously optimizing the interface between the solar array and battery. First, the variable supply is fixed at 12.8V dc—the voltage of a fully charged battery— and linked to the battery point of the circuit. Cut Off of battery from load voltage is 10.8 volt. A PIC16F72 for small size and inbuilt analog inputs is used to determine voltage level of battery and solar panel..It also describes how the disadvantages of analog circuit are overcome by this controller. The flow chart is also provided.

  4. Lithium-Ion Batteries for Aerospace Applications

    Science.gov (United States)

    Surampudi, S.; Halpert, G.; Marsh, R. A.; James, R.

    1999-01-01

    This presentation reviews: (1) the goals and objectives, (2) the NASA and Airforce requirements, (3) the potential near term missions, (4) management approach, (5) the technical approach and (6) the program road map. The objectives of the program include: (1) develop high specific energy and long life lithium ion cells and smart batteries for aerospace and defense applications, (2) establish domestic production sources, and to demonstrate technological readiness for various missions. The management approach is to encourage the teaming of universities, R&D organizations, and battery manufacturing companies, to build on existing commercial and government technology, and to develop two sources for manufacturing cells and batteries. The technological approach includes: (1) develop advanced electrode materials and electrolytes to achieve improved low temperature performance and long cycle life, (2) optimize cell design to improve specific energy, cycle life and safety, (3) establish manufacturing processes to ensure predictable performance, (4) establish manufacturing processes to ensure predictable performance, (5) develop aerospace lithium ion cells in various AH sizes and voltages, (6) develop electronics for smart battery management, (7) develop a performance database required for various applications, and (8) demonstrate technology readiness for the various missions. Charts which review the requirements for the Li-ion battery development program are presented.

  5. Energy management with stochastic constraint and multi-objective optimization algorithm for electric vehicle battery swap station%采用随机约束和多目标算法的电动汽车换电站能量管理

    Institute of Scientific and Technical Information of China (English)

    刘玉娇; 蒋传文; 王旭; 申景双

    2013-01-01

    The optimization of energy management for electric vehicle battery swap station is researched.Because the energy management of electric vehicle battery swap station has a certain risk,its model,built with the consideration of the uncertainties in electricity price and power demand,takes the expectation and variance of cost as its objectives and solved by a multi-objective optimization algorithm based on immune clone method.Simulative results show that,the electricity purchase cost of battery swap station is lowered by the optimized energy management and the power network obtains benefit by the load transfer.%针对电动汽车换电站的能量管理进行优化.由于实时电价环境下电动汽车换电站的能量管理具有一定的风险性,因此所建的模型考虑了电动汽车换电需求和市场电价的不确定性,是以运行成本的期望和方差为目标的电动汽车换电站的能量管理模型,并采用基于免疫克隆选择的多目标智能优化算法进行求解.算例仿真结果表明通过所提出的模型可以实现电动汽车换电站购电成本的降低,并通过负荷转移给电网带来好处.

  6. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Takeshi; Iida, Masaaki; Moriki, Yasuyuki

    1994-10-18

    A reactor core is divided into a plurality of coolants flowrate regions, and electromagnetic pumps exclusively used for each of the flowrate regions are disposed to distribute coolants flowrates in the reactor core. Further, the flowrate of each of the electromagnetic pumps is automatically controlled depending on signals from a temperature detector disposed at the exit of the reactor core, so that the flowrate of the region can be controlled optimally depending on the burning of reactor core fuels. Then, the electromagnetic pumps disposed for every divided region are controlled respectively, so that the coolants flowrate distribution suitable to each of the regions can be attained. Margin for fuel design is decreased, fuels are used effectively, as well as an operation efficiency can be improved. Moreover, since the electromagnetic pump has less flow resistance compared with a mechanical type pump, and flow resistance of the reactor core flowrate control mechanism is eliminated, greater circulating flowrate can be ensured after occurrence of accident in a natural convection using a buoyancy of coolants utilizable for after-heat removal as a driving force. (N.H.).

  7. EBT reactor analysis

    International Nuclear Information System (INIS)

    This report summarizes the results of a recent ELMO Bumpy Torus (EBT) reactor study that includes ring and core plasma properties with consistent treatment of coupled ring-core stability criteria and power balance requirements. The principal finding is that constraints imposed by these coupling and other physics and technology considerations permit a broad operating window for reactor design optimization. Within this operating window, physics and engineering systems analysis and cost sensitivity studies indicate that reactors with approx. 6 to 10%, P approx. 1200 to 1700 MW(e), wall loading approx. 1.0 to 2.5 MW/m2, and recirculating power fraction (including ring-sustaining power and all other reactors auxiliaries) approx. 10 to 15% are possible. A number of concept improvements are also proposed that are found to offer the potential for further improvement of the reactor size and parameters. These include, but are not limited to, the use of: (1) supplementary coils or noncircular mirror coils to improve magnetic geometry and reduce size, (2) energetic ion rings to improve ring power requirements, (3) positive potential to enhance confinement and reduce size, and (4) profile control to improve stability and overall fusion power density

  8. Waste Heat Boiler Denitration Reactor Optimization and Transformation%余热锅炉中脱硝反应器的优化及改造

    Institute of Scientific and Technical Information of China (English)

    王佰仟; 杨凯; 赵永刚

    2015-01-01

    国内电站实际应用SCR(选择性催化还原)烟气脱硝技术过程中,经常出现中、低负荷下SCR反应器入口烟温低于SCR催化剂的最佳反应温度窗口,严重时甚至低于正常反应温度等问题,导致SCR反应器运行效率明显偏低,严重影响余热锅炉的脱硝效率、NOx排放浓度和氨逃逸率。因此,需要在不影响余热锅炉整体运行下,有效提高SCR反应效率,维持SCR催化剂的较高活性,保证原SCR反应器系统高效稳定运行的是很有必要的。通过热力计算分析对比分析了高压过热器及高压蒸发器两种不同方案下主要热力参数的变化并根据工程实际情况建立了SCR脱硝反应器的模型图,文章分析了夏季运行工况,50%负荷情况下各个烟气参数,对SCR脱硝反应器流场模拟计算时的有关设置进行了说明。介绍了评价SCR脱硝反应器效果的两个指标,即流场均匀性和温度场均匀性指标。%The practical application of domestic power station SCR (Selective Catalytic Reduction) of lfue gas denitriifcation technology process, often appear in, SCR reactor inlet temperature below the low load smoke SCR catalyst optimum reaction temperature window, serious or even lower than normal The reaction temperature and other issues, leading to the SCR reactor is signiifcantly lower operating efifciency, seriously affect the denitration efifciency waste heat boiler, NOx emission concentration and ammonia slip rate. Therefore, without affecting the overall operation of the waste heat boiler, the SCR effectively improve the reaction efifciency, to maintain a high activity of the SCR catalyst, it is necessary to ensure that the original SCR reactor system efifcient and stable operation. Calculation of comparative analysis by thermal changes under high pressure and high-pressure evaporator superheater two different thermodynamic parameters of the main program and in accordance with the actual

  9. Lithium-Ion Battery Cell Cycling and Usage Analysis in a Heavy-Duty Truck Field Study

    OpenAIRE

    Pontus Svens; Mårten Behm; Göran Lindbergh

    2015-01-01

    This paper presents results from a field test performed on commercial power-optimized lithium-ion battery cells cycled on three heavy-duty trucks. The goal with this study was to age battery cells in a hybrid electric vehicle (HEV) environment and find suitable methods for identifying cell ageing. The battery cells were cycled on in-house developed equipment intended for testing on conventional vehicles by emulating an HEV environment. A hybrid strategy that allows battery usage to vary with...

  10. Lithium-Ion Battery Cell Cycling and Usage Analysis in a Heavy-Duty Truck Field Study

    OpenAIRE

    Pontus Svens; Mårten Behm; Göran Lindbergh

    2015-01-01

    This paper presents results from a field test performed on commercial power-optimized lithium-ion battery cells cycled on three heavy-duty trucks. The goal with this study was to age battery cells in a hybrid electric vehicle (HEV) environment and find suitable methods for identifying cell ageing. The battery cells were cycled on in-house developed equipment intended for testing on conventional vehicles by emulating an HEV environment. A hybrid strategy that allows battery usage to vary withi...

  11. Enzymatic synthesis of farnesyl laurate in organic solvent: initial water activity, kinetics mechanism, optimization of continuous operation using packed bed reactor and mass transfer studies.

    Science.gov (United States)

    Rahman, N K; Kamaruddin, A H; Uzir, M H

    2011-08-01

    The influence of water activity and water content was investigated with farnesyl laurate synthesis catalyzed by Lipozyme RM IM. Lipozyme RM IM activity depended strongly on initial water activity value. The best results were achieved for a reaction medium with an initial water activity of 0.11 since it gives the best conversion value of 96.80%. The rate constants obtained in the kinetics study using Ping-Pong-Bi-Bi and Ordered-Bi-Bi mechanisms with dead-end complex inhibition of lauric acid were compared. The corresponding parameters were found to obey the Ordered-Bi-Bi mechanism with dead-end complex inhibition of lauric acid. Kinetic parameters were calculated based on this model as follows: V (max) = 5.80 mmol l(-1) min(-1) g enzyme(-1), K (m,A) = 0.70 mmol l(-1) g enzyme(-1), K (m,B) = 115.48 mmol l(-1) g enzyme(-1), K (i) = 11.25 mmol l(-1) g enzyme(-1). The optimum conditions for the esterification of farnesol with lauric acid in a continuous packed bed reactor were found as the following: 18.18 cm packed bed height and 0.9 ml/min substrate flow rate. The optimum molar conversion of lauric acid to farnesyl laurate was 98.07 ± 0.82%. The effect of mass transfer in the packed bed reactor has also been studied using two models for cases of reaction limited and mass transfer limited. A very good agreement between the mass transfer limited model and the experimental data obtained indicating that the esterification in a packed bed reactor was mass transfer limited.

  12. Contribution to the optimal design of an hybrid parallel power-train: choice of a battery model; Contribution a la conception optimale d'une motorisation hybride parallele. Choix d'un modele d'accumulateur

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, E.

    2004-09-15

    This work deals with the dynamical and energetic modeling of a 42 V NiMH battery, the model of which is taking into account into a control law for an hybrid electrical vehicle. Using an inventory of the electrochemical phenomena, an equivalent electrical scheme has been established. In this model, diffusion phenomena were represented using non integer derivatives. This tool leads to a very good approximation of diffusion phenomena, nevertheless such a pure mathematical approach did not allow to represent energetic losses inside the battery. Consequently, a second model, made of a series of electric circuits has been proposed to represent energetic transfers. This second model has been used in the determination of a control law which warrants an autonomous management of electrical energy embedded in a parallel hybrid electrical vehicle, and to prevent deep discharge of the battery. (author)

  13. A novel Gaussian model based battery state estimation approach: State-of-Energy

    International Nuclear Information System (INIS)

    Highlights: • The Gaussian model is employed to construct a novel battery model. • The genetic algorithm is used to implement model parameter identification. • The AIC is used to decide the best hysteresis order of the battery model. • A novel battery SoE estimator is proposed and verified by two kinds of batteries. - Abstract: State-of-energy (SoE) is a very important index for battery management system (BMS) used in electric vehicles (EVs), it is indispensable for ensuring safety and reliable operation of batteries. For achieving battery SoE accurately, the main work can be summarized in three aspects. (1) In considering that different kinds of batteries show different open circuit voltage behaviors, the Gaussian model is employed to construct the battery model. What is more, the genetic algorithm is employed to locate the optimal parameter for the selecting battery model. (2) To determine an optimal tradeoff between battery model complexity and prediction precision, the Akaike information criterion (AIC) is used to determine the best hysteresis order of the combined battery model. Results from a comparative analysis show that the first-order hysteresis battery model is thought of being the best based on the AIC values. (3) The central difference Kalman filter (CDKF) is used to estimate the real-time SoE and an erroneous initial SoE is considered to evaluate the robustness of the SoE estimator. Lastly, two kinds of lithium-ion batteries are used to verify the proposed SoE estimation approach. The results show that the maximum SoE estimation error is within 1% for both LiFePO4 and LiMn2O4 battery datasets

  14. Assessing Pretreatment Reactor Scaling Through Empirical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lischeske, James J.; Crawford, Nathan C.; Kuhn, Erik; Nagle, Nicholas J.; Schell, Daniel J.; Tucker, Melvin P.; McMillan, James D.; Wolfrum, Edward J.

    2016-12-01

    Pretreatment is a critical step in the biochemical conversion of lignocellulosic biomass to fuels and chemicals. Due to the complexity of the physicochemical transformations involved, predictively scaling up technology from bench- to pilot-scale is difficult. This study examines how pretreatment effectiveness under nominally similar reaction conditions is influenced by pretreatment reactor design and scale using four different pretreatment reaction systems ranging from a 3 g batch reactor to a 10 dry-ton/d continuous reactor. The reactor systems examined were an Automated Solvent Extractor (ASE), Steam Explosion Reactor (SER), ZipperClave(R) reactor (ZCR), and Large Continuous Horizontal-Screw Reactor (LHR). To our knowledge, this is the first such study performed on pretreatment reactors across a range of reaction conditions (time and temperature) and at different reactor scales. The comparative pretreatment performance results obtained for each reactor system were used to develop response surface models for total xylose yield after pretreatment and total sugar yield after pretreatment followed by enzymatic hydrolysis. Near- and very-near-optimal regions were defined as the set of conditions that the model identified as producing yields within one and two standard deviations of the optimum yield. Optimal conditions identified in the smallest-scale system (the ASE) were within the near-optimal region of the largest scale reactor system evaluated. A reaction severity factor modeling approach was shown to inadequately describe the optimal conditions in the ASE, incorrectly identifying a large set of sub-optimal conditions (as defined by the RSM) as optimal. The maximum total sugar yields for the ASE and LHR were 95%, while 89% was the optimum observed in the ZipperClave. The optimum condition identified using the automated and less costly to operate ASE system was within the very-near-optimal space for the total xylose yield of both the ZCR and the LHR, and was

  15. 中国实验快堆主蒸汽系统优化设计及分析研究%Optimization design and analysis on main steam system of China Experimental Fast Reactor

    Institute of Scientific and Technical Information of China (English)

    纪西胜; 吴强; 牛敬娟

    2012-01-01

    The function of the main steam system of China Experimental Fast Reactor (CEFR) is to transfer the steam from SG to the turbine to generate power and to discharge the steam from reactor in case of accidental condition. However, the reactor automatically shut down many times due to improper operation of valves, affecting the stability of the system and increasing operation cost. In order to optimize the steam system process flow, this paper introduced the bypass and worked out the design parameters, and finally gave qualitative analysis of the calculation result in special condition.%中国实验快堆三回路主蒸汽系统主要功能是将蒸汽发生器产生的蒸汽送至汽轮发电机组,辅助功能是在事故工况下排出反应堆产生的热量.调试期间多次因主蒸汽系统阀门手动操作而引起停堆,影响了系统的稳定性,增加了运行成本.本文对主蒸汽系统进行了优化设计、增加旁路管道,并对此条件下的过热器反暖操作和特殊工况下压力损失计算结果进行定性分析,确定了设计参数,优化了主蒸汽系统的工艺流程.

  16. Compact Reactor

    International Nuclear Information System (INIS)

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date

  17. Ni-MH battery modelling for ambient intelligence applications

    CERN Document Server

    Szente-Varga, D; Rencz, M

    2008-01-01

    Mobile devices, like sensor networks and MEMS actuators use mobile power supplies to ensure energy for their operation. These are mostly batteries. The lifetime of the devices depends on the power consumption and on the quality and capacitance of the battery. Though the integrated circuits and their power consumption improve continually, their clock frequency also increases with the time, and the resultant power consumption seems not to vary, or slightly increase. On the other hand, the properties of batteries are developing much slower, necessitating the optimization of their usage on system level.

  18. Smart materials for energy storage in Li-ion batteries

    Directory of Open Access Journals (Sweden)

    Ashraf E Abdel-Ghany

    2016-01-01

    Full Text Available Advanced lithium-ion batteries contain smart materials having the function of insertion electrodes in the form of powders with specific and optimized electrochemical properties. Different classes can be considered: the surface modified active particles at either positive or negative electrodes, the nano-composite electrodes and the blended materials. In this paper, various systems are described, which illustrate the improvement of lithium-ion batteries in term of specific energy and power, thermal stability and life cycling.

  19. Determination of the zeolite optimal diameter for the settlement of nitrifying bacteria in an aerobic bed fluidized reactor to eliminate ammonia nitrogen

    Directory of Open Access Journals (Sweden)

    Santiago Pozo-Antonio

    2014-01-01

    Full Text Available En este trabajo se realiza la determinación del diámetro de zeo lita óptimo que es empleado como soporte microbiano en un react or aerobio de lecho fluidizado. El d iseño de dicho reactor es reco mendado por Navarro y Palladino [1]. Para el presente estudio, la zeolita es triturada y clasificada granulométricamente. Posteriormente, so n escogidos, arbitrariamente, los diámetros 0.5, 1 y 2 mm para realizar el estudio de adhesión microbiana. Tras el estudio de adherencia d e bacterias nitrificantes, a pesar de que los valores obtenidos para cada diámetro no presentan diferencias significativas entre sí, se e scoge el agregado de 1 mm por conseguir valores de adherencia m ayores. Una vez escogido el diámetro de zeolita se realiza la construcc ión del reactor aerobio de lecho fluidizado propuesto por Navar ro y Palladino [1], con una alimentación de 1.35 mL.m -1 y una capacidad de 8 L. La cantidad de zeolita optimizada para una correcta fluidización es de 500 g, lo que es un 8% del volumen total de la columna. Se observa una buena eficiencia de reducción de la materia orgánica durante el funcionamiento, siendo esta de 50%.

  20. Nonlinear Dynamics Traction Battery Modeling

    OpenAIRE

    Szumanowski, Antoni

    2010-01-01

    The assumed method and effective model are very accurate according to error checking results of the NiMH and Li-Ion batteries. The modeling method is valid for different types of batteries. The model can be conveniently used for vehicle simulation because the battery model is accurately approximated by mathematical equations. The model provides the methodology for designing a battery management system and calculating the SOC. The influence of temperature on battery performance is analyzed acc...