Numerical Analysis of Flow Field in Generator End-Winding Region

Directory of Open Access Journals (Sweden)

Wei Tong

2008-01-01

Full Text Available Cooling in an end-winding region of a high-powered, large-sized generator still remains a challenge today because of a number of factors: a larger number of parts/components with irregular geometries, complexity in cooling flow paths, flow splitting and mixing, and interactions between rotor-induced rotating flows and nonrotating flows from stationary sections. One of the key challenges is to model cooling flows passing through armature bars, which are made up of bundles of strands of insulated copper wires and are bent oppositely to cross each other. This work succeeded in modeling a complex generator end-winding region with great efforts to simplify the model by treating the armature bar region as a porous medium. The flow and pressure fields at the end-winding region were investigated numerically using an axial symmetric computational fluid dynamics (CFD model. Based on the analysis, the cooling flow rate at each flow branch (rotor-stator gap, rotor subslot, outside space block, and small ventilation holes to the heat exchanger was determined, and the high-pressure gradient zones were identified. The CFD results have been successfully used to optimize the flow path configuration for improving the generator operation performance, and the control of the cooling flow, as well as minimizing windage losses and flow-introduced noises.

The use of energy in China: Tracing the flow of energy from primary source to demand drivers

International Nuclear Information System (INIS)

Ma, Linwei; Allwood, Julian M.; Cullen, Jonathan M.; Li, Zheng

2012-01-01

We present a map of the transformation of energy in China as a Sankey diagram. After a review of previous work, and a statement of methodology, our main work has been the identification, evaluation, and treatment of appropriate data sources. This data is used to construct the Sankey diagram, in which flows of energy are traced from energy sources through end-use conversion devices, passive systems and final services to demand drivers. The resulting diagram provides a convenient and clear snapshot of existing energy transformations in China which can usefully be compared with a similar global analysis and which emphasises the potential for improvements in energy efficiency in ‘passive systems’. More broadly, it gives a basis for examining and communicating future energy scenarios, including changes to demand, changes to the supply mix, changes in efficiency and alternative provision of existing services. -- Highlights: ► A Sankey Diagram has been created to show the complete picture of energy transformation in China. ► The Diagram traces energy transformations from source to final service. ► The diagram is organised by technologies, enabling prioritisation and allowing future calculation of efficiencies. ► The diagram is contrasted with an equivalent diagram for global energy use. ► Armed with the diagram we can now examine the system-wide consequences of future changes to China's energy system.

End-to-End Traffic Flow Modeling of the Integrated SCaN Network

Science.gov (United States)

Cheung, K.-M.; Abraham, D. S.

2012-05-01

In this article, we describe the analysis and simulation effort of the end-to-end traffic flow for the Integrated Space Communications and Navigation (SCaN) Network. Using the network traffic derived for the 30-day period of July 2018 from the Space Communications Mission Model (SCMM), we generate the wide-area network (WAN) bandwidths of the ground links for different architecture options of the Integrated SCaN Network. We also develop a new analytical scheme to model the traffic flow and buffering mechanism of a store-and-forward network. It is found that the WAN bandwidth of the Integrated SCaN Network is an important differentiator of different architecture options, as the recurring circuit costs of certain architecture options can be prohibitively high.

A new NAMA framework for dispersed energy end-use sectors

International Nuclear Information System (INIS)

Cheng, C.-C.

2010-01-01

This paper presents a new approach for a nationally appropriate mitigation actions (NAMA) framework that can unlock the huge potential for greenhouse gas mitigation in dispersed energy end-use sectors in developing countries; specifically, the building sector and the industrial sector. These two sectors make up the largest portions of energy consumption in developing countries. However, due to multiple barriers and lack of effective polices, energy efficiency in dispersed energy end-use sectors has not been effectively put into practice. The new NAMA framework described in this paper is designed to fulfill the demand for public policies and public sector investment in developing countries and thereby boost private sector investment through project based market mechanisms, such as CDM. The new NAMA framework is designed as a need-based mechanism which effectively considers the conditions of each developing country. The building sector is used as an example to demonstrate how NAMA measures can be registered and implemented. The described new NAMA framework has the ability to interface efficiently with Kyoto Protocol mechanisms and to facilitate a systematic uptake for GHG emission reduction investment projects. This is an essential step to achieve the global climate change mitigation target and support sustainable development in developing countries.

Energy End-Use : Industry

NARCIS (Netherlands)

Banerjee, R.; Gong, Y; Gielen, D.J.; Januzzi, G.; Marechal, F.; McKane, A.T.; Rosen, M.A.; Es, D. van; Worrell, E.

2012-01-01

The industrial sector accounts for about 30% of the global final energy use and accounts for about 115 EJ of final energy use in 2005. 1Cement, iron and steel, chemicals, pulp and paper and aluminum are key energy intensive materials that account for more than half the global industrial use. There

End-to-End Flow Control for Visual-Haptic Communication under Bandwidth Change

Science.gov (United States)

Yashiro, Daisuke; Tian, Dapeng; Yakoh, Takahiro

This paper proposes an end-to-end flow controller for visual-haptic communication. A visual-haptic communication system transmits non-real-time packets, which contain large-size visual data, and real-time packets, which contain small-size haptic data. When the transmission rate of visual data exceeds the communication bandwidth, the visual-haptic communication system becomes unstable owing to buffer overflow. To solve this problem, an end-to-end flow controller is proposed. This controller determines the optimal transmission rate of visual data on the basis of the traffic conditions, which are estimated by the packets for haptic communication. Experimental results confirm that in the proposed method, a short packet-sending interval and a short delay are achieved under bandwidth change, and thus, high-precision visual-haptic communication is realized.

A new NAMA framework for dispersed energy end-use sectors

DEFF Research Database (Denmark)

Cheng, Chia-Chin

2010-01-01

This paper presents a new approach for a nationally appropriate mitigation actions (NAMA) framework that can unlock the huge potential for greenhouse gas mitigation in dispersed energy end-use sectors in developing countries; specifically, the building sector and the industrial sector. These two ...

Energy end use statistics and estimations in the Polish household sector

International Nuclear Information System (INIS)

Gilecki, R.

1997-01-01

The energy statistics in Poland was in the past concentrated on energy production and industrial consumption, but little information was available on the households energy consumption. This data unavailability was an important barrier for the various analyses and forecasting of the energy balance developments. In the recent years some successful attempts were made to acquire a wider and more reliable picture of household energy consumption. The households surveys were made and some existing data were analyzed and verified. The better and more detailed picture of households energy use was in this way constructed. The breakdown of energy consumption by end-use categories (space heating, water heating, cooking, electrical appliances) was quite reliably estimated. Important international cooperation and guidance was used in the course of Polish households energy consumption research. (author). 6 refs

Energy end use statistics and estimations in the Polish household sector

Energy Technology Data Exchange (ETDEWEB)

Gilecki, R [Energy Information Centre, Warsaw (Poland)

1997-09-01

The energy statistics in Poland was in the past concentrated on energy production and industrial consumption, but little information was available on the households energy consumption. This data unavailability was an important barrier for the various analyses and forecasting of the energy balance developments. In the recent years some successful attempts were made to acquire a wider and more reliable picture of household energy consumption. The households surveys were made and some existing data were analyzed and verified. The better and more detailed picture of households energy use was in this way constructed. The breakdown of energy consumption by end-use categories (space heating, water heating, cooking, electrical appliances) was quite reliably estimated. Important international cooperation and guidance was used in the course of Polish households energy consumption research. (author). 6 refs.

Inverted end-Hall-type low-energy high-current gaseous ion source

International Nuclear Information System (INIS)

Oks, E. M.; Vizir, A. V.; Shandrikov, M. V.; Yushkov, G. Yu.; Grishin, D. M.; Anders, A.; Baldwin, D. A.

2008-01-01

A novel approach to low-energy, high-current, gaseous ion beam generation was explored and an ion source based on this technique has been developed. The source utilizes a dc high-current (up to 20 A) gaseous discharge with electron injection into the region of ion generation. Compared to the conventional end-Hall ion source, the locations of the discharge anode and cathode are inverted: the cathode is placed inside the source and the anode outside, and correspondingly, the discharge current is in the opposite direction. The discharge operates in a diverging axial magnetic field, similar to the end-Hall source. Electron generation and injection is accomplished by using an additional arc discharge with a ''cold'' (filamentless) hollow cathode. Low plasma contamination is achieved by using a low discharge voltage (avoidance of sputtering), as well as by a special geometric configuration of the emitter discharge electrodes, thereby filtering (removing) the erosion products stemming from the emitter cathode. The device produces a dc ion flow with energy below 20 eV and current up to 2.5 A onto a collector of 500 cm 2 at 25 cm from the source edge, at a pressure ≥0.02 Pa and gas flow rate ≥14 SCCM. The ion energy spread is 2 to 3 eV (rms). The source is characterized by high reliability, low maintenance, and long lifetime. The beam contains less than 0.1% of metallic ions. The specific electric energy consumption is 400 eV per ion registered at the collector. The source operates with noble gases, nitrogen, oxygen, and hydrocarbons. Utilizing biasing, it can be used for plasma sputtering, etching, and other ion technologies

Oscillatory flow at the end of parallel-plate stacks: phenomenological and similarity analysis

International Nuclear Information System (INIS)

Mao Xiaoan; Jaworski, Artur J

2010-01-01

This paper addresses the physics of the oscillatory flow in the vicinity of a series of parallel plates forming geometrically identical channels. This type of flow is particularly relevant to thermoacoustic engines and refrigerators, where a reciprocating flow is responsible for the desirable energy transfer, but it is also of interest to general fluid mechanics of oscillatory flows past bluff bodies. In this paper, the physics of an acoustically induced flow past a series of plates in an isothermal condition is studied in detail using the data provided by PIV imaging. Particular attention is given to the analysis of the wake flow during the ejection part of the flow cycle, where either closed recirculating vortices or alternating vortex shedding can be observed. This is followed by a similarity analysis of the governing Navier-Stokes equations in order to derive the similarity criteria governing the wake flow behaviour. To this end, similarity numbers including two types of Reynolds number, the Keulegan-Carpenter number and a non-dimensional stack configuration parameter, d/h, are considered and their influence on the phenomena are discussed.

Network modeling for reverse flows of end-of-life vehicles

International Nuclear Information System (INIS)

Ene, Seval; Öztürk, Nursel

2015-01-01

Highlights: • We developed a network model for reverse flows of end-of-life vehicles. • The model considers all recovery operations for end-of-life vehicles. • A scenario-based model is used for uncertainty to improve real case applications. • The model is adequate to real case applications for end-of-life vehicles recovery. • Considerable insights are gained from the model by sensitivity analyses. - Abstract: Product recovery operations are of critical importance for the automotive industry in complying with environmental regulations concerning end-of-life products management. Manufacturers must take responsibility for their products over the entire life cycle. In this context, there is a need for network design methods for effectively managing recovery operations and waste. The purpose of this study is to develop a mathematical programming model for managing reverse flows in end-of-life vehicles’ recovery network. A reverse flow is the collection of used products from consumers and the transportation of these products for the purpose of recycling, reuse or disposal. The proposed model includes all operations in a product recovery and waste management network for used vehicles and reuse for vehicle parts such as collection, disassembly, refurbishing, processing (shredding), recycling, disposal and reuse of vehicle parts. The scope of the network model is to determine the numbers and locations of facilities in the network and the material flows between these facilities. The results show the performance of the model and its applicability for use in the planning of recovery operations in the automotive industry. The main objective of recovery and waste management is to maximize revenue and minimize pollution in end-of-life product operations. This study shows that with an accurate model, these activities may provide economic benefits and incentives in addition to protecting the environment

Network modeling for reverse flows of end-of-life vehicles

Energy Technology Data Exchange (ETDEWEB)

Ene, Seval; Öztürk, Nursel

2015-04-15

Highlights: • We developed a network model for reverse flows of end-of-life vehicles. • The model considers all recovery operations for end-of-life vehicles. • A scenario-based model is used for uncertainty to improve real case applications. • The model is adequate to real case applications for end-of-life vehicles recovery. • Considerable insights are gained from the model by sensitivity analyses. - Abstract: Product recovery operations are of critical importance for the automotive industry in complying with environmental regulations concerning end-of-life products management. Manufacturers must take responsibility for their products over the entire life cycle. In this context, there is a need for network design methods for effectively managing recovery operations and waste. The purpose of this study is to develop a mathematical programming model for managing reverse flows in end-of-life vehicles’ recovery network. A reverse flow is the collection of used products from consumers and the transportation of these products for the purpose of recycling, reuse or disposal. The proposed model includes all operations in a product recovery and waste management network for used vehicles and reuse for vehicle parts such as collection, disassembly, refurbishing, processing (shredding), recycling, disposal and reuse of vehicle parts. The scope of the network model is to determine the numbers and locations of facilities in the network and the material flows between these facilities. The results show the performance of the model and its applicability for use in the planning of recovery operations in the automotive industry. The main objective of recovery and waste management is to maximize revenue and minimize pollution in end-of-life product operations. This study shows that with an accurate model, these activities may provide economic benefits and incentives in addition to protecting the environment.

End users heat energy savings using thermostat regulation valves radiators, v. 16(64)

International Nuclear Information System (INIS)

Jakimovska, Emilija Misheva; Potsev, Eftim

2008-01-01

Billing the used heat energy offers the opportunity to motivate end users to use the heat energy rationally and to save the energy. Installing the thermostat valves on the radiators it is possible frequently to regulate the room temperature and to use the heat gains, obtaining comfortable climate in the apartments and saving the energy. Thermostat valves give the possibility to use the heat energy rationally and save the energy, and these way and users can regulate the heat energy consumption according to their own level of thermal comfort. (Author)

End users heat energy savings using thermostat regulation valves radiators, v. 16(63)

International Nuclear Information System (INIS)

Jakimovska, Emilija Misheva; Potsev, Eftim

2008-01-01

Billing the used heat energy offers the opportunity to motivate end users to use the heat energy rationally and to save the energy. Installing the thermostat valves on the radiators it is possible frequently to regulate the room temperature and to use the heat gains, obtaining comfortable climate in the apartments and saving the energy. Thermostat valves give the possibility to use the heat energy rationally and save the energy, and these way and users can regulate the heat energy consumption according to their own level of thermal comfort. (Author)

India Energy Outlook: End Use Demand in India to 2020

Energy Technology Data Exchange (ETDEWEB)

de la Rue du Can, Stephane; McNeil, Michael; Sathaye, Jayant

2009-03-30

Integrated economic models have been used to project both baseline and mitigation greenhouse gas emissions scenarios at the country and the global level. Results of these scenarios are typically presented at the sectoral level such as industry, transport, and buildings without further disaggregation. Recently, a keen interest has emerged on constructing bottom up scenarios where technical energy saving potentials can be displayed in detail (IEA, 2006b; IPCC, 2007; McKinsey, 2007). Analysts interested in particular technologies and policies, require detailed information to understand specific mitigation options in relation to business-as-usual trends. However, the limit of information available for developing countries often poses a problem. In this report, we have focus on analyzing energy use in India in greater detail. Results shown for the residential and transport sectors are taken from a previous report (de la Rue du Can, 2008). A complete picture of energy use with disaggregated levels is drawn to understand how energy is used in India and to offer the possibility to put in perspective the different sources of end use energy consumption. For each sector, drivers of energy and technology are indentified. Trends are then analyzed and used to project future growth. Results of this report provide valuable inputs to the elaboration of realistic energy efficiency scenarios.

Average regional end-use energy price projections to the year 2030

International Nuclear Information System (INIS)

1991-01-01

The energy prices shown in this report cover the period from 1991 through 2030. These prices reflect sector/fuel price projections from the Annual Energy Outlook 1991 (AEO) base case, developed using the Energy Information Administration's (EIA) Intermediate Future Forecasting System (IFFS) forecasting model. Projections through 2010 are AEO base case forecasts. Projections for the period from 2011 through 2030 were developed separately from the AEO for this report, and the basis for these projections is described in Chapter 3. Projections in this report include average energy prices for each of four Census Regions for the residential, commercial, industrial, and transportation end-use sectors. Energy sources include electricity, distillate fuel oil, liquefied petroleum gas, motor gasoline, residual fuel oil, natural gas, and steam coal. (VC)

Semantic Complex Event Processing over End-to-End Data Flows

Energy Technology Data Exchange (ETDEWEB)

Zhou, Qunzhi [University of Southern California; Simmhan, Yogesh; Prasanna, Viktor K.

2012-04-01

Emerging Complex Event Processing (CEP) applications in cyber physical systems like SmartPower Grids present novel challenges for end-to-end analysis over events, flowing from heterogeneous information sources to persistent knowledge repositories. CEP for these applications must support two distinctive features - easy specification patterns over diverse information streams, and integrated pattern detection over realtime and historical events. Existing work on CEP has been limited to relational query patterns, and engines that match events arriving after the query has been registered. We propose SCEPter, a semantic complex event processing framework which uniformly processes queries over continuous and archived events. SCEPteris built around an existing CEP engine with innovative support for semantic event pattern specification and allows their seamless detection over past, present and future events. Specifically, we describe a unified semantic query model that can operate over data flowing through event streams to event repositories. Compile-time and runtime semantic patterns are distinguished and addressed separately for efficiency. Query rewriting is examined and analyzed in the context of temporal boundaries that exist between event streams and their repository to avoid duplicate or missing results. The design and prototype implementation of SCEPterare analyzed using latency and throughput metrics for scenarios from the Smart Grid domain.

Analysis of energy end-use efficiency policy in Spain

International Nuclear Information System (INIS)

Collado, Rocío Román; Díaz, María Teresa Sanz

2017-01-01

The implementation of saving measures and energy efficiency entails the need to evaluate achievements in terms of energy saving and spending. This paper aims at analysing the effectiveness and economic efficiency of energy saving measures implemented in the Energy Savings and Efficiency Action Plan (2008–2012) (EAP4+) in Spain for 2010. The lack of assessment related to energy savings achieved and public spending allocated by the EAP4+ justifies the need of this analysis. The results show that the transport and building sectors seem to be the most important, from the energy efficiency perspective. Although they did not reach the direct energy savings that were expected, there is scope for reduction with the appropriate energy measures. For the effectiveness indicator, the best performance are achieved by public service, agricultural and fisheries and building sectors, while in terms of energy efficiency per monetary unit, the best results are achieved by transport, industry and agriculture sectors. Authors conclude that it is necessary that central, regional and local administrations will get involved, in order to get better estimates of the energy savings achieved and thus to affect the design of future energy efficiency measures at the lowest possible cost to the citizens. - Highlights: • Energy end-use efficiency policy is analysed in terms of energy savings and spending. • The energy savings achieved by some measures are not always provided. • The total energy savings achieved by transport and building sectors are large. • Different levels of administration should get involved in estimating energy savings.

Industrial energy-flow management

International Nuclear Information System (INIS)

Lampret, Marko; Bukovec, Venceslav; Paternost, Andrej; Krizman, Srecko; Lojk, Vito; Golobic, Iztok

2007-01-01

Deregulation of the energy market has created new opportunities for the development of new energy-management methods based on energy assets, risk management, energy efficiency and sustainable development. Industrial energy-flow management in pharmaceutical systems, with a responsible approach to sustainable development, is a complex task. For this reason, an energy-information centre, with over 14,000 online measured data/nodes, was implemented. This paper presents the energy-flow rate, exergy-flow rate and cost-flow rate diagrams, with emphasis on cost-flow rate per energy unit or exergy unit of complex pharmaceutical systems

Development of a global computable general equilibrium model coupled with detailed energy end-use technology

International Nuclear Information System (INIS)

Fujimori, Shinichiro; Masui, Toshihiko; Matsuoka, Yuzuru

2014-01-01

Highlights: • Detailed energy end-use technology information is considered within a CGE model. • Aggregated macro results of the detailed model are similar to traditional model. • The detailed model shows unique characteristics in the household sector. - Abstract: A global computable general equilibrium (CGE) model integrating detailed energy end-use technologies is developed in this paper. The paper (1) presents how energy end-use technologies are treated within the model and (2) analyzes the characteristics of the model’s behavior. Energy service demand and end-use technologies are explicitly considered, and the share of technologies is determined by a discrete probabilistic function, namely a Logit function, to meet the energy service demand. Coupling with detailed technology information enables the CGE model to have more realistic representation in the energy consumption. The proposed model in this paper is compared with the aggregated traditional model under the same assumptions in scenarios with and without mitigation roughly consistent with the two degree climate mitigation target. Although the results of aggregated energy supply and greenhouse gas emissions are similar, there are three main differences between the aggregated and the detailed technologies models. First, GDP losses in mitigation scenarios are lower in the detailed technology model (2.8% in 2050) as compared with the aggregated model (3.2%). Second, price elasticity and autonomous energy efficiency improvement are heterogeneous across regions and sectors in the detailed technology model, whereas the traditional aggregated model generally utilizes a single value for each of these variables. Third, the magnitude of emissions reduction and factors (energy intensity and carbon factor reduction) related to climate mitigation also varies among sectors in the detailed technology model. The household sector in the detailed technology model has a relatively higher reduction for both energy

Energy and Water Consumption End-Use Survey in Commercial and Industrial Sectors in Georgia

Data.gov (United States)

US Agency for International Development — The objective of survey was to collect statistical energy and water end-use data for commercial and industrial sectors. The survey identified volumes of energy and...

Energy conservation: policy issues and end-use scenarios of savings potential

Energy Technology Data Exchange (ETDEWEB)

1978-09-01

The enclosed work is based on previous research during this fiscal year, contained in Construction of Energy Conservation Scenarios: Interim Report of Work in Progress, June 1978. Five subjects were investigated and summaries were published for each subject in separate publications. This publication summarizes policy issues on the five subjects: tradeoffs of municipal solid-waste-processing alternatives (economics of garbage collection; mechanical versus home separation of recyclables); policy barriers and investment decisions in industry (methodology for identification of potential barriers to industrial energy conservation; process of industrial investment decision making); energy-efficient recreational travel (information system to promote energy-efficient recreational travel; recreational travel; national importance and individual decision making); energy-efficient buildings (causes of litigation against energy-conservation building codes; description of the building process); and end-use energy-conservation data base and scenaerios (residential; commercial; transportation; and industrial).

Flow boundary conditions for chain-end adsorbing polymer blends.

Science.gov (United States)

Zhou, Xin; Andrienko, Denis; Delle Site, Luigi; Kremer, Kurt

2005-09-08

Using the phenol-terminated polycarbonate blend as an example, we demonstrate that the hydrodynamic boundary conditions for a flow of an adsorbing polymer melt are extremely sensitive to the structure of the epitaxial layer. Under shear, the adsorbed parts (chain ends) of the polymer melt move along the equipotential lines of the surface potential whereas the adsorbed additives serve as the surface defects. In response to the increase of the number of the adsorbed additives the surface layer becomes thinner and solidifies. This results in a gradual transition from the slip to the no-slip boundary condition for the melt flow, with a nonmonotonic dependence of the slip length on the surface concentration of the adsorbed ends.

Flow structures in end-view plane of slender delta wing

Directory of Open Access Journals (Sweden)

Sahin Besir

2017-01-01

Full Text Available Present investigation focuses on unsteady flow structures in end-view planes at the trailing edge of delta wing, X/C=1.0, where consequences of vortex bursting and stall phenomena vary according to angles of attack over the range of 25° ≤ α ≤ 35° and yaw angles, β over the range of 0° ≤ β ≤ 20°. Basic features of counter rotating vortices in end-view planes of delta win with 70° sweep angle, Λ are examined both qualitatively and quantitatively using Rhodamine dye and the PIV system. In the light of present experiments it is seen that with increasing yaw angle, β symmetrical flow structure is disrupted continuously. Dispersed wind-ward side leading edge vortices cover a large part of flow domain, on the other hand, lee-ward side leading edge vortices cover only a small portion of flow domain.

Improving energy efficiency and smart grid program analysis with agent-based end-use forecasting models

International Nuclear Information System (INIS)

Jackson, Jerry

2010-01-01

Electric utilities and regulators face difficult challenges evaluating new energy efficiency and smart grid programs prompted, in large part, by recent state and federal mandates and financial incentives. It is increasingly difficult to separate electricity use impacts of individual utility programs from the impacts of increasingly stringent appliance and building efficiency standards, increasing electricity prices, appliance manufacturer efficiency improvements, energy program interactions and other factors. This study reviews traditional approaches used to evaluate electric utility energy efficiency and smart-grid programs and presents an agent-based end-use modeling approach that resolves many of the shortcomings of traditional approaches. Data for a representative sample of utility customers in a Midwestern US utility are used to evaluate energy efficiency and smart grid program targets over a fifteen-year horizon. Model analysis indicates that a combination of the two least stringent efficiency and smart grid program scenarios provides peak hour reductions one-third greater than the most stringent smart grid program suggesting that reductions in peak demand requirements are more feasible when both efficiency and smart grid programs are considered together. Suggestions on transitioning from traditional end-use models to agent-based end-use models are provided.

End-tidal control vs. manually controlled minimal-flow anesthesia: a prospective comparative trial.

Science.gov (United States)

Wetz, A J; Mueller, M M; Walliser, K; Foest, C; Wand, S; Brandes, I F; Waeschle, R M; Bauer, M

2017-11-01

To ensure safe general anesthesia, manually controlled anesthesia requires constant monitoring and numerous manual adjustments of the gas dosage, especially for low- and minimal-flow anesthesia. Oxygen flow-rate and administration of volatile anesthetics can also be controlled automatically by anesthesia machines using the end-tidal control technique, which ensures constant end-tidal concentrations of oxygen and anesthetic gas via feedback and continuous adjustment mechanisms. We investigated the hypothesis that end-tidal control is superior to manually controlled minimal-flow anesthesia (0.5 l/min). In this prospective trial, we included 64 patients undergoing elective surgery under general anesthesia. We analyzed the precision of maintenance of the sevoflurane concentration (1.2-1.4%) and expiratory oxygen (35-40%) and the number of necessary adjustments. Target-concentrations of sevoflurane and oxygen were maintained at more stable levels with the use of end-tidal control (during the first 15 min 28% vs. 51% and from 15 to 60 min 1% vs. 19% deviation from sevoflurane target, P tidal oxygen (5, IQR 3-6). The target-concentrations were reached earlier with the use of end-tidal compared with manual controlled minimal-flow anesthesia but required slightly greater use of anesthetic agents (6.9 vs. 6.0 ml/h). End-tidal control is a superior technique for setting and maintaining oxygen and anesthetic gas concentrations in a stable and rapid manner compared with manual control. Consequently, end-tidal control can effectively support the anesthetist. © 2017 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Energy, cost, and emission end-use profiles of homes: An Ontario (Canada) case study

International Nuclear Information System (INIS)

Aydinalp Koksal, Merih; Rowlands, Ian H.; Parker, Paul

2015-01-01

Highlights: • Hourly electricity consumption data of seven end-uses from 25 homes are analyzed. • Hourly load, cost, and emission profiles of end-uses are developed and categorized. • Side-by-side analysis of energy, cost, and environmental effects is conducted. • Behaviour and outdoor temperature based end-uses are determined. • Share of each end-use in the total daily load, cost, and emission is determined. - Abstract: Providing information on the temporal distributions of residential electricity end-uses plays a major role in determining the potential savings in residential electricity demand, cost, and associated emissions. While the majority of the studies on disaggregated residential electricity end-use data provided hourly usage profiles of major appliances, only a few of them presented analysis on the effect of hourly electricity consumption of some specific end-uses on household costs and emissions. This study presents side-by-side analysis of energy, cost, and environment effects of hourly electricity consumption of the main electricity end-uses in a sample of homes in the Canadian province of Ontario. The data used in this study are drawn from a larger multi-stakeholder project in which electricity consumption of major end-uses at 25 homes in Milton, Ontario, was monitored in five-minute intervals for six-month to two-year periods. In addition to determining the hourly price of electricity during the monitoring period, the hourly carbon intensity is determined using fuel type hourly generation and the life cycle greenhouse gas intensities specifically determined for Ontario’s electricity fuel mix. The hourly load, cost, and emissions profiles are developed for the central air conditioner, furnace, clothes dryer, clothes washer, dishwasher, refrigerator, and stove and then grouped into eight day type categories. The side-by-side analysis of categorized load, cost, and emission profiles of the seven electricity end-uses provided information on

Mapping the global flow of steel: from steelmaking to end-use goods.

Science.gov (United States)

Cullen, Jonathan M; Allwood, Julian M; Bambach, Margarita D

2012-12-18

Our society is addicted to steel. Global demand for steel has risen to 1.4 billion tonnes a year and is set to at least double by 2050, while the steel industry generates nearly a 10th of the world's energy related CO₂ emissions. Meeting our 2050 climate change targets would require a 75% reduction in CO₂ emissions for every tonne of steel produced and finding credible solutions is proving a challenge. The starting point for understanding the environmental impacts of steel production is to accurately map the global steel supply chain and identify the biggest steel flows where actions can be directed to deliver the largest impact. In this paper we present a map of global steel, which for the first time traces steel flows from steelmaking, through casting, forming, and rolling, to the fabrication of final goods. The diagram reveals the relative scale of steel flows and shows where efforts to improve energy and material efficiency should be focused.

Flow energy conversion system

International Nuclear Information System (INIS)

Sargsyan, R.A.

2011-01-01

A cost-effective hydropower system called here Flow Energy Converter was developed, patented, manufactured and tested for water pumping, electricity generation and other purposes especially useful for the rural communities. The system consists of water-driven turbine with plane-surface blades, power transmission means and pump and/or generator. Working sample of the Flow Energy Converter was designed and manufactured at the Institute of Radio Physics and Electronics

Fluid flow nozzle energy harvesters

Science.gov (United States)

Sherrit, Stewart; Lee, Hyeong Jae; Walkemeyer, Phillip; Winn, Tyler; Tosi, Luis Phillipe; Colonius, Tim

2015-04-01

Power generation schemes that could be used downhole in an oil well to produce about 1 Watt average power with long-life (decades) are actively being developed. A variety of proposed energy harvesting schemes could be used to extract energy from this environment but each of these has their own limitations that limit their practical use. Since vibrating piezoelectric structures are solid state and can be driven below their fatigue limit, harvesters based on these structures are capable of operating for very long lifetimes (decades); thereby, possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. An initial survey [1] identified that spline nozzle configurations can be used to excite a vibrating piezoelectric structure in such a way as to convert the abundant flow energy into useful amounts of electrical power. This paper presents current flow energy harvesting designs and experimental results of specific spline nozzle/ bimorph design configurations which have generated suitable power per nozzle at or above well production analogous flow rates. Theoretical models for non-dimensional analysis and constitutive electromechanical model are also presented in this paper to optimize the flow harvesting system.

High energy density Z-pinch plasmas using flow stabilization

Energy Technology Data Exchange (ETDEWEB)

Shumlak, U., E-mail: shumlak@uw.edu; Golingo, R. P., E-mail: shumlak@uw.edu; Nelson, B. A., E-mail: shumlak@uw.edu; Bowers, C. A., E-mail: shumlak@uw.edu; Doty, S. A., E-mail: shumlak@uw.edu; Forbes, E. G., E-mail: shumlak@uw.edu; Hughes, M. C., E-mail: shumlak@uw.edu; Kim, B., E-mail: shumlak@uw.edu; Knecht, S. D., E-mail: shumlak@uw.edu; Lambert, K. K., E-mail: shumlak@uw.edu; Lowrie, W., E-mail: shumlak@uw.edu; Ross, M. P., E-mail: shumlak@uw.edu; Weed, J. R., E-mail: shumlak@uw.edu [Aerospace and Energetics Research Program, University of Washington, Seattle, Washington, 98195-2250 (United States)

2014-12-15

The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

Network modeling for reverse flows of end-of-life vehicles.

Science.gov (United States)

Ene, Seval; Öztürk, Nursel

2015-04-01

Product recovery operations are of critical importance for the automotive industry in complying with environmental regulations concerning end-of-life products management. Manufacturers must take responsibility for their products over the entire life cycle. In this context, there is a need for network design methods for effectively managing recovery operations and waste. The purpose of this study is to develop a mathematical programming model for managing reverse flows in end-of-life vehicles' recovery network. A reverse flow is the collection of used products from consumers and the transportation of these products for the purpose of recycling, reuse or disposal. The proposed model includes all operations in a product recovery and waste management network for used vehicles and reuse for vehicle parts such as collection, disassembly, refurbishing, processing (shredding), recycling, disposal and reuse of vehicle parts. The scope of the network model is to determine the numbers and locations of facilities in the network and the material flows between these facilities. The results show the performance of the model and its applicability for use in the planning of recovery operations in the automotive industry. The main objective of recovery and waste management is to maximize revenue and minimize pollution in end-of-life product operations. This study shows that with an accurate model, these activities may provide economic benefits and incentives in addition to protecting the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Detector and front-end electronics of a fissile mass flow monitoring system

International Nuclear Information System (INIS)

Paulus, M.J.; Uckan, T.; Lenarduzzi, R.; Mullens, J.A.; Castleberry, K.N.; McMillan, D.E.; Mihalczo, J.T.

1997-01-01

A detector and front-end electronics unit with secure data transmission has been designed and implemented for a fissile mass flow monitoring system for fissile mass flow of gases and liquids in a pipe. The unit consists of 4 bismuth germanate (BGO) scintillation detectors, pulse-shaping and counting electronics, local temperature sensors, and on-board local area network nodes which locally acquire data and report to the master computer via a secure network link. The signal gain of the pulse-shaping circuitry and energy windows of the pulse-counting circuitry are periodicially self calibrated and self adjusted in situ using a characteristic line in the fissile material pulse height spectrum as a reference point to compensate for drift such as in the detector gain due to PM tube aging. The temperature- dependent signal amplitude variations due to the intrinsic temperature coefficients of the PM tube gain and BGO scintillation efficiency have been characterized and real-time gain corrections introduced. The detector and electronics design, measured intrinsic performance of the detectors and electronics, and the performance of the detector and electronics within the fissile mass flow monitoring system are described

Instantaneous flow field above the free end of finite-height cylinders and prisms

International Nuclear Information System (INIS)

Rostamy, N.; Sumner, D.; Bergstrom, D.J.; Bugg, J.D.

2013-01-01

Highlights: • PIV measurements of the flow above the free end of finite-height bodies. • Effect of cross-sectional shape of the models on the instantaneous flow. • Small-scale structures generated by the separated shear layer were revealed. • Effect of aspect ratio on the reattachment of the separated flow on the free end. -- Abstract: The flow above the free ends of surface-mounted finite-height circular cylinders and square prisms was studied experimentally using particle image velocimetry (PIV). Cylinders and prisms with aspect ratios of AR = 9, 7, 5, and 3 were tested at a Reynolds number of Re = 4.2 × 10 4 . The bodies were mounted normal to a ground plane and were partially immersed in a turbulent zero-pressure-gradient boundary layer, where the boundary layer thickness relative to the body width was δ/D = 1.6. PIV measurements were made above the free ends of the bodies in a vertical plane aligned with the flow centreline. The present PIV results provide insight into the effects of aspect ratio and body shape on the instantaneous flow field. The recirculation zone under the separated shear layer is larger for the square prism of AR = 3 compared to the more slender prism of AR = 9. Also, for a square prism with low aspect ratio (AR = 3), the influence of the reverse flow over the free end surface becomes more significant compared to that for a higher aspect ratio (AR = 9). For the circular cylinder, a cross-stream vortex forms within the recirculation zone. As the aspect ratio of the cylinder decreases, the reattachment point of the separated flow on the free end surface moves closer to the trailing edge. For both the square prism and circular cylinder cases, the instantaneous velocity vector field and associated in-plane vorticity field revealed small-scale structures mostly generated by the separated shear layer

Analysis of a DSM program using an end use model; End use model wo mochiita DSM program no bunseki

Energy Technology Data Exchange (ETDEWEB)

Asano, H.; Takahashi, M.; Okada, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1997-01-30

An end use model used in the United States who is advanced in demand-side management (DSM) was used to discuss possibilities of designing and evaluating Japan`s future DSM measures. The end use model assumes energy demand based on such factors as device characteristics, meteorological data, energy prices, user characteristics, market characteristics and DSM measures. The model calculates energy demand amount by end uses basically by multiplying assumptions on device unit requirement, device retention rate, and number of users. A representative tool as an end use model that handles load shapes is the hourly electric load model (HELM). It assumes an annual load curve and predicts a maximum system load. The present discussions have performed estimation on demand for consumer use air conditioners in a day in which a maximum summer load occurs in a reference year, estimation on load in a maximum load day in an estimated year, and estimation on weather sensitivity of loads. 5 refs., 5 figs.

Use of synthetic series of monthly flows in calculating the marginal cost of energy of the national interconnected power system of Peru

International Nuclear Information System (INIS)

Sarango J, D.; Velasquez B, T.

2009-01-01

In this research it was determined the feasibility of using synthetic series of monthly average flow for the determination of the average marginal cost of energy in the National Interconnected Electric System of Peru, SEIN, taking as a case study of implementing bar tariff setting in 2004, where it was used the PERSEO model for planning, simulation and optimization of the hydrothermal system in Peru. The model is currently used by the Deputy Manager of tariff regulation (GART) of the Agency for Supervision of Investment in Energy and Mining - OSINERGMIN. The model use as hydrological information the average monthly flow series of tributaries to the historical attractions of the 23 river basins of the SEIN, one of the main is the basin of the Junin Lake, whose water is used by the Mantaro and Restitution hydroelectric, generating almost 20% of the power of our country. With the HEC-4 program, developed by the Hydrological Engineering Center of the USA, from the time series of monthly historical flows tributary to the Junin Lake, 50 series were generated synthetic monthly flow, determined from them a dry series, a average series and a wet series, information that was used in the PERSEO model to calculate the average marginal cost of energy of SEIN for each case. The results obtained from the average marginal cost of energy with the use of synthetic series of monthly flows, for the dry case, average case and wet case, with the PERSEO model, compared to the historical event, are lower in order of 1.14, 1.55 and 0.87 US $/MWh, the results will determine a decline in energy prices for end users, such as the domestic, commercial, industrial and mining users. (author).

Electricity of nuclear origin and primary and end-use energy consumption; Electricite nucleaire et consommation d'energie primaire et finale

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

In France, the electricity of nuclear origin corresponds to about 40% of the primary energy consumption, while electricity as a whole represents about 23% of the end-use energy. This apparent paradox can be explained by 2 methodological points: 1 - the primary energy consumption, in the case of electricity, includes only the energy of nuclear, hydraulic, wind, photovoltaic and geothermal origin. On the other hand, the end-use energy consumption includes all forms of electricity consumed, i.e. the electricity of both primary and secondary origin. 2 - By international convention, the coefficients used to convert MWth into tpe (ton of petroleum equivalent) can change according to two factors: the power generation source and the type of kWh considered, either produced or consumed. The coexistence of different concepts and definitions is justified by the different usages made with them. Therefore, calculations referring to different definitions or equivalence coefficients are not immediately comparable. (J.S.)

Tracing China's energy flow and carbon dioxide flow based on Sankey diagrams

Energy Technology Data Exchange (ETDEWEB)

Wang, Feiyin; Wang, Pengtao; Xu, Xiaomeng; Dong, Lihui; Xue, Honglai; Fu, Shuai [China University of Mining and Technology, Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources, Beijing (China); China University of Mining and Technology, Faculty of Resources and Safety Engineering, Beijing (China); Ji, Yingxu [State Grid Jibei Electric Power Company Limited, Langfang Power Supply Company, Langfang (China)

2017-10-15

China has promised to optimize its energy structure and reduce its CO{sub 2} emission in the 13th Five-Year Plan. To track the energy structure, the conversions, efficiencies, end consumptions of total energy and coal and the whole CO{sub 2} emission status, the energy flow, coal flow and CO{sub 2} flow in 2015 were, respectively, drawn at the national level based on Sankey diagrams. Besides, each provincial fossil fuel structure, CO{sub 2} structure and CO{sub 2} intensity were calculated and plotted. It is mainly found that China's energy structure consisted of 69.2% of coal, 19.9% of oil, 6.3% of natural gas and 4.7% of non-fossil energy, where 45.5% of energy was consumed by industry and 23.9% by losses and statistical difference; coal was distributed to industry (55.6%), etc., with a utilization rate of 70.1%; and CO{sub 2} were derived from coal (84.7%), oil (11.1%) and natural gas (4.2%), of which 39.0% was released through the process of thermal power generation and 19.4% by industry. The structures of fossil fuels and their CO{sub 2} emissions together with the evolution of CO{sub 2} intensity at the provincial level and the regional level were also given. Besides, two pieces of policy implications were proposed to provide the government with reference. (orig.)

Energy consumption of electricity end uses in Malaysian historic buildings

Energy Technology Data Exchange (ETDEWEB)

Kamaruzzaman, Syahrul N.; Edwards, Rodger E.; Zawawi, Emma M.A.

2007-07-15

Malaysia has inherited hundreds of heritage buildings from the past including those from the Indian, Chinese and Colonial eras apart from the indigenous traditional buildings. These buildings have the most unique ecstatic value from the viewpoint of architecture, culture, art, etc. Malaysian economy boom in 1980s spurred the need for more buildings especially in large cities. As a result, most of the historic buildings have been converted and transformed into commercial use. As reported by METP, Malaysian buildings energy uses are reflected by the energy consumption in the industrial and commercial sectors. Most of the buildings' energy consumption is electricity, used for running and operating the plants, lighting, lifts and escalators and other equipment in the buildings. These are amongst the factors that have resulted in the high demand for electricity in Malaysia. As outlined in the eighth Malaysia Plan, Malaysia is taking steps in conserving energy and reducing energy consumption on electricity consumption in building. This paper aims to present the breakdown of the major electricity end uses characteristics of historic buildings in Malaysia. The analysis was performed on annual data, allowing comparison with published benchmarks to give an indication of efficiency. Based on data collected a 'normalisation' calculated electricity consumption was established with the intention of improving the comparison between buildings in different climatic regions or with different occupancy patterns. This is useful for identifying where the design needed further attention and helped pinpoint problem areas within a building. It is anticipated that this study would give a good indication on the electricity consumption characteristics of historic buildings in Malaysia. (Author)

A computational study of inviscid hypersonic flows using energy relaxation method

International Nuclear Information System (INIS)

Nagdewe, Suryakant; Kim, H. D.; Shevare, G. R.

2008-01-01

Reasonable analysis of hypersonic flows requires a thermodynamic non-equilibrium model to properly simulate strong shock waves or high pressure and temperature states in the flow field. The energy relaxation method (ERM) has been used to model such a non-equilibrium effect which is generally expressed as a hyperbolic system of equations with a stiff relaxation source term. Relaxation time that is multiplied with source terms is responsible for nonequilibrium in the system. In the present study, a numerical analysis has been carried out with varying values of relaxation time for several hypersonic flows with AUSM (advection upstream splitting method) as a numerical scheme. Vibration modes of thermodynamic nonequilibrium effects are considered. The results obtained showed that, as the relaxation time reduces to zero, the solution marches toward equilibrium, while it shows non-equilibrium effects, as the relaxation time increases. The present computations predicted the experiment results of hypersonic flows with good accuracy. The work carried out suggests that the present energy relaxation method can be robust for analysis of hypersonic flows

The use of dead-end and cross-flow nanofiltration to purify prebiotic oligosaccharides from reaction mixtures

Directory of Open Access Journals (Sweden)

Alistair S. Grandison

2002-11-01

Full Text Available Nanofiltration (NF of model sugar solutions and commercial oligosaccharide mixtures were studied in both dead-end and cross-flow modes. Preliminary trials, with a dead-end filtration cell, demonstrated the feasibility of fractionating monosaccharides from disaccharides and oligosaccharides in mixtures, using loose nanofiltration (NF-CA-50, NF-TFC-50 membranes. During the nanofiltration purification of a commercial oligosaccharide mixture, yields of 19% (w w-1 for the monosaccharides and 88% (w w-1 for di, and oligosaccharides were obtained for the NF-TFC-50 membrane after four filtration steps, indicating that removal of the monosaccharides is possible, with only minor losses of the oligosaccharide content of the mixture. The effects of pressure, feed concentration, and filtration temperature were studied in similar experiments carried out in a cross-flow system, in full recycle mode of operation. The rejection rates of the sugar components increased with increasing pressure, and decreased with both increasing total sugar concentration in the feed and increasing temperature. Continuous diafiltration (CD purification of model sugar solutions and commercial oligosaccharide mixtures using NF-CA-50 (at 25oC and DS-5-DL (at 60oC membranes, gave yield values of 14 to 18% for the monosaccharide, 59 to 89% for the disaccharide and 81 to 98% for the trisaccharide present in the feed. The study clearly demonstrates the potential of cross flow nanofiltration in the purification of oligosaccharide mixtures from the contaminant monosaccharides.

Using Free Flow Energy Cumulation in Wind and Hydro Power Production

Directory of Open Access Journals (Sweden)

Lev Ktitorov

2016-09-01

Full Text Available When approaching a conventional wind turbine, the air flow is slowed down and widened. This results in a loss of turbine efficiency. In order to exploit wind or water flow power as effectively as possible, it was suggested that the turbine should be placed inside a shroud, which consists of 4 wing-shaped surfaces. Two internal airfoils improve the turbine performance by speeding up the flow acting on the turbine blades, two external wings create a field of low pressure behind the turbine, thus, helping to draw more mass flow to the turbine and avoid the loss of efficiency due to flow deceleration.  The system accumulates kinetic energy of the flow in a small volume where the smaller (and, therefore, cheaper turbine can be installed. A smaller system can be installed inside the bigger one, which would help to accumulate even more kinetic energy on the turbine. We call this method the kinetic energy summation with local flow redistribution. Both experiments and CFD simulations demonstrate a significant increase in velocity and generated mechanical power in comparison of those for a bare turbine.

End-use energy characterization and conservation potentials at DoD Facilities: An analysis of electricity use at Fort Hood, Texas

Energy Technology Data Exchange (ETDEWEB)

Akbari, H.; Konopacki, S.

1995-05-01

This report discusses the application of the LBL`s End-use Disaggregation Algorithm (EDA) to a DoD installation and presents hourly reconciled end-use data for all major building types and end uses. The project initially focused on achieving these objectives and pilot-testing the methodology at Fort Hood, Texas. Fort Hood, with over 5000 buildings was determined to have representative samples of nearly all of the major building types in use on DoD installations. These building types at Fort Hood include: office, administration, vehicle maintenance, shop, hospital, grocery store, retail store, car wash, church, restaurant, single-family detached housing, two and four-plex housings, and apartment building. Up to 11 end uses were developed for each prototype, consisting of 9 electric and 2 gas; however, only electric end uses were reconciled against known data and weather conditions. The electric end uses are space cooling, ventilation, cooking, miscellaneous/plugs, refrigeration, exterior lighting, interior lighting, process loads, and street lighting. The gas end uses are space heating and hot water heating. Space heating energy-use intensities were simulated only. The EDA was applied to 10 separate feeders from the three substations at Fort Hood. The results from the analyses of these ten feeders were extrapolated to estimate energy use by end use for the entire installation. The results show that administration, residential, and the bar-rack buildings are the largest consumers of electricity for a total of 250GWh per year (74% of annual consumption). By end use, cooling, ventilation, miscellaneous, and indoor lighting consume almost 84% of total electricity use. The contribution to the peak power demand is highest by residential sector (35%, 24 MW), followed by administration buildings (30%), and barrack (14%). For the entire Fort Hood installation, cooling is 54% of the peak demand (38 MW), followed by interior lighting at 18%, and miscellaneous end uses by 12%.

Long term building energy demand for India: Disaggregating end use energy services in an integrated assessment modeling framework

International Nuclear Information System (INIS)

Chaturvedi, Vaibhav; Eom, Jiyong; Clarke, Leon E.; Shukla, Priyadarshi R.

2014-01-01

With increasing population, income, and urbanization, meeting the energy service demands for the building sector will be a huge challenge for Indian energy policy. Although there is broad consensus that the Indian building sector will grow and evolve over the coming century, there is little understanding of the potential nature of this evolution over the longer term. The present study uses a technologically detailed, service based building energy model nested in the long term, global, integrated assessment framework, GCAM, to produce scenarios of the evolution of the Indian buildings sector up through the end of the century. The results support the idea that as India evolves toward developed country per-capita income levels, its building sector will largely evolve to resemble those of the currently developed countries (heavy reliance on electricity both for increasing cooling loads and a range of emerging appliance and other plug loads), albeit with unique characteristics based on its climate conditions (cooling dominating heating and even more so with climate change), on fuel preferences that may linger from the present (for example, a preference for gas for cooking), and vestiges of its development path (including remnants of rural poor that use substantial quantities of traditional biomass). - Highlights: ► Building sector final energy demand in India will grow to over five times by century end. ► Space cooling and appliance services will grow substantially in the future. ► Energy service demands will be met predominantly by electricity and gas. ► Urban centers will face huge demand for floor space and building energy services. ► Carbon tax policy will have little effect on reducing building energy demands

End user prices in liberalised energy markets

Energy Technology Data Exchange (ETDEWEB)

Lijesen, M.G. [Afdeling Energie en Grondstoffen, Centraal Planbureau CPB, Den Haag (Netherlands)

2002-12-01

As European energy markets move towards deregulation, energy prices shift from classic 'cost plus' prices towards market prices. We develop a model for the retail and wholesale energy markets in Europe, based on Bertrand competition in a two part pricing structure with switching costs. We use the model to forecast end user electricity and natural gas prices and find that the introduction of competition in energy retail and wholesale markets will decrease standing charges, lowering total costs for energy users. A larger number of entrants, a cost advantage for one of the suppliers, or lower switching costs reduces standing charges further.

Annual Energy Usage Reduction and Cost Savings of a School: End-Use Energy Analysis

Science.gov (United States)

Alghoul, M. A.; Bakhtyar, B.; Asim, Nilofar; Sopian, K.

2014-01-01

Buildings are among the largest consumers of energy. Part of the energy is wasted due to the habits of users and equipment conditions. A solution to this problem is efficient energy usage. To this end, an energy audit can be conducted to assess the energy efficiency. This study aims to analyze the energy usage of a primary school and identify the potential energy reductions and cost savings. A preliminary audit was conducted, and several energy conservation measures were proposed. The energy conservation measures, with reference to the MS1525:2007 standard, were modelled to identify the potential energy reduction and cost savings. It was found that the school's usage of electricity exceeded its need, incurring an excess expenditure of RM 2947.42. From the lighting system alone, it was found that there is a potential energy reduction of 5489.06 kWh, which gives a cost saving of RM 2282.52 via the improvement of lighting system design and its operating hours. Overall, it was found that there is a potential energy reduction and cost saving of 20.7% when the energy conservation measures are earnestly implemented. The previous energy intensity of the school was found to be 50.6 kWh/m2/year, but can theoretically be reduced to 40.19 kWh/mm2/year. PMID:25485294

End-to-end Information Flow Security Model for Software-Defined Networks

Directory of Open Access Journals (Sweden)

D. Ju. Chaly

2015-01-01

Full Text Available Software-defined networks (SDN are a novel paradigm of networking which became an enabler technology for many modern applications such as network virtualization, policy-based access control and many others. Software can provide flexibility and fast-paced innovations in the networking; however, it has a complex nature. In this connection there is an increasing necessity of means for assuring its correctness and security. Abstract models for SDN can tackle these challenges. This paper addresses to confidentiality and some integrity properties of SDNs. These are critical properties for multi-tenant SDN environments, since the network management software must ensure that no confidential data of one tenant are leaked to other tenants in spite of using the same physical infrastructure. We define a notion of end-to-end security in context of software-defined networks and propose a semantic model where the reasoning is possible about confidentiality, and we can check that confidential information flows do not interfere with non-confidential ones. We show that the model can be extended in order to reason about networks with secure and insecure links which can arise, for example, in wireless environments.The article is published in the authors’ wording.

One-dimensional energy flow model for poroelastic material

International Nuclear Information System (INIS)

Kim, Jung Soo; Kang, Yeon June

2009-01-01

This paper presents a one-dimensional energy flow model to investigate the energy behavior for poroelastic media coupled with acoustical media. The proposed energy flow model is expressed by an independent energy governing equation that is classified into each wave component propagating in poroelastic media. The energy governing equation is derived using the General Energetic Method (GEM). To facilitate a comparison with the classical solution based on the conventional displacement-base formulation, approximate solutions of energy density and intensity are obtained. Furthermore, the limitations and usability of the proposed energy flow model for poroelastic media are described.

END-OF-USE PRODUCTS IN REVERSE LOGISTICS

OpenAIRE

Marta Starostka-Patyk

2007-01-01

Reverse logistics is a very useful tool for enterprises which have to deal with end-of-use products. Forward logistics is not able to manage them, because they show up on the beginning of reverse supply chain. That is the reason for growing importance of reverse flows. Reverse logistics is quite new logistics system. This paper presents the idea of reverse logistics and end-of-use products problems.

Increasing operations profitability using an end-to-end, wireless internet, gas monitoring system

Energy Technology Data Exchange (ETDEWEB)

McDougall, M. [Northrock Resources Ltd., AB (Canada); Benterud, K. [zed.i solutions, inc., Calgary, AB (Canada)

2004-10-01

Implementation by Northrock Resources Ltd., a wholly-owned subsidiary of Unocal Corporation, of a fully integrated end-to-end gas measurement and production analysis system, is discussed. The system, dubbed Smart-Alek(TM), utilizes public wireless communications and a web browser only delivery system to provide seamless well visibility to a desk-top computer. Smart-Alek(TM) is an example of a new type of end-to-end electronic gas flow measurement system, known as FINE(TM), which is an acronym for Field Intelligence Network and End-User Interface. The system delivers easy-to-use, complete, reliable and cost effective production information, far more effective than is possible to obtain with conventional SCADA technology. By installing the system, Northrock was able to increase gas volumes with more accurate electronic flow measurement in place of mechanical charts, with very low technical maintenance, and at a reduced operating cost. It is emphasized that deploying the technology alone will produce only partial benefits; to realize full benefits it is also essential to change grass roots operating practices, aiming at timely decision-making at the field level. 5 refs., 5 figs.

Malaysia commercial energy flow: status and structure

International Nuclear Information System (INIS)

Ridzuan Abdul Mutalib; Maragatham Kumar; Nik Arlina Nik Ali; Abi Muttaqin Jalal Bayar; Aisya Raihan Abdul Kadir; Muhammed Zulfakar Zolkaffly; Azlinda Aziz; Jamal Khaer Ibrahim

2008-08-01

With further growth of Malaysia economy, future development of the energy sector in Malaysia is vital to ensure targeted growth. Commercial Energy continues to play a major role in ensuring a balanced energy mix for power generation due to a potential increase in energy demand from various sectors, especially the industrial sector. This paper presents the status and structure of Malaysia Commercial Energy Flow, which gives an overview of the flow of all types of energy sources from primary energy supply to final energy use, and also the potential for nuclear power in electricity generation in Malaysia. (Author)

A Galloping Energy Harvester with Attached Flow

Science.gov (United States)

Denissenko, Petr; Khovanov, Igor; Tucker-Harvey, Sam

2017-11-01

Aeroelastic energy harvesters are a promising technology for the operation of wireless sensors and microelectromechanical systems, as well as providing the possibility of harvesting wind energy in applications were conventional wind turbines are ineffective, such as in highly turbulent flows, or unreliable, such as in harsh environmental conditions. The development of aeroelastic energy harvesters to date has focused on the flutter of airfoils, the galloping of prismatic structures, and the vortex induced vibrations. We present a novel type of galloping energy harvester with the flow becoming attached when the oscillation amplitude is high enough. With the flow attached, the harvester blade acts closer to an aerofoil than a bluff body, which results in a higher efficiency. The dynamics of a prototype device has been characterised experimentally with the use of a motion tracking system. The flow structure in the vicinity of the device has been studied using smoke visualisation and PIV measurements. A lumped parameter mathematical model has been developed and related to the experimental results.

A nonlinear flow-induced energy harvester by considering effects of fictitious springs

Science.gov (United States)

Zhang, Guangcheng; Lin, Yueh-Jaw

2018-01-01

In this paper, a newly proposed energy harvesting approach involving nonlinear coupling effects is demonstrated by utilizing a pair of inducing bluff bodies that are put on both sides of the flag-shaped cantilever beam, and placed in a side-by-side configuration to harvest the energy of the flow. One patch of macro fiber composite is attached to the fixed end of the cantilever beam to facilitate converting the kinetic energy into electric power. It is the first time in recent literature that two fluid dynamic phenomena (i.e. the vortex shedding and the Bernoulli effect) are considered simultaneously in the flow-induced energy harvesting field. The fictitious springs are introduced to explain the nonlinear characteristics of the proposed structure. With the effect of the fictitious springs, the speed range of the flow-induced energy harvester is extended. The proposed structure not only improves the output of the induced-based energy harvester compared to one that has just one cylinder, but can also be utilized in an actual hostile ambient environment. The experimental results for the energy harvester prototype are also investigated. The output power of the energy harvester with two cylinders (D = 25 mm) is measured to be 1.12 μW when the flow speed is 0.325 m s-1 and the center-to-center transverse spacing is 45 mm. This research also delves into the geometric variations of the proposed structure and its optimization.

Vibration energy harvesting in a small channel fluid flow using piezoelectric transducer

Energy Technology Data Exchange (ETDEWEB)

Hassan, Md. Mehedi, E-mail: buetmehedi10@gmail.com; Hossain, Md. Yeam, E-mail: yeamhossain@gmail.com; Mazumder, Rakib, E-mail: rakibmazumder46075@gmail.com; Rahman, Roussel, E-mail: roussel.rahman@gmail.com; Rahman, Md. Ashiqur, E-mail: ashiqurrahman@me.buet.ac.bd [Department of Mechanical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka-1000 (Bangladesh)

2016-07-12

This work is aimed at developing a way to harvest energy from a fluid stream with the application of piezoelectric transducers in a small channel. In this COMSOL Multiphysics based simulation study, it is attempted to harvest energy from the abundant renewable source of energy available in the form of kinetic energy of naturally occurring flow of fluids. The strategy involves harnessing energy from a fluid-actuator through generation of couples, eddies and vortices, resulting from the stagnation and separation of flow around a semi-circular bluff-body attached to a cantilever beam containing a piezoceramic layer. Fluctuation of fluidic pressure impulse on the beam due to vortex shedding and varying lift forces causes the flexible cantilever beam to oscillate in the direction normal to the fluid flow in a periodic manner. The periodic application and release of a mechanical strain upon the beam effected a generation of electric potential within the piezoelectric layer, thus enabling extraction of electrical energy from the kinetic energy of the fluid. The piezoelectric material properties and transducer design are kept unchanged throughout the study, whereas the configuration is tested with different fluids and varying flow characteristics. The size and geometry of the obstructing entity are systematically varied to closely inspect the output from different iterations and for finding the optimum design parameters. The intermittent changes in the generated forces and subsequent variation in the strain on the beam are also monitored to find definitive relationship with the electrical energy output.

Energy and material flows of megacities.

Science.gov (United States)

Kennedy, Christopher A; Stewart, Iain; Facchini, Angelo; Cersosimo, Igor; Mele, Renata; Chen, Bin; Uda, Mariko; Kansal, Arun; Chiu, Anthony; Kim, Kwi-Gon; Dubeux, Carolina; Lebre La Rovere, Emilio; Cunha, Bruno; Pincetl, Stephanie; Keirstead, James; Barles, Sabine; Pusaka, Semerdanta; Gunawan, Juniati; Adegbile, Michael; Nazariha, Mehrdad; Hoque, Shamsul; Marcotullio, Peter J; González Otharán, Florencia; Genena, Tarek; Ibrahim, Nadine; Farooqui, Rizwan; Cervantes, Gemma; Sahin, Ahmet Duran

2015-05-12

Understanding the drivers of energy and material flows of cities is important for addressing global environmental challenges. Accessing, sharing, and managing energy and material resources is particularly critical for megacities, which face enormous social stresses because of their sheer size and complexity. Here we quantify the energy and material flows through the world's 27 megacities with populations greater than 10 million people as of 2010. Collectively the resource flows through megacities are largely consistent with scaling laws established in the emerging science of cities. Correlations are established for electricity consumption, heating and industrial fuel use, ground transportation energy use, water consumption, waste generation, and steel production in terms of heating-degree-days, urban form, economic activity, and population growth. The results help identify megacities exhibiting high and low levels of consumption and those making efficient use of resources. The correlation between per capita electricity use and urbanized area per capita is shown to be a consequence of gross building floor area per capita, which is found to increase for lower-density cities. Many of the megacities are growing rapidly in population but are growing even faster in terms of gross domestic product (GDP) and energy use. In the decade from 2001-2011, electricity use and ground transportation fuel use in megacities grew at approximately half the rate of GDP growth.

Measurement of β-decay end point energy with planar HPGe detector

Science.gov (United States)

Bhattacharjee, T.; Pandit, Deepak; Das, S. K.; Chowdhury, A.; Das, P.; Banerjee, D.; Saha, A.; Mukhopadhyay, S.; Pal, S.; Banerjee, S. R.

2014-12-01

The β - γ coincidence measurement has been performed with a segmented planar Hyper-Pure Germanium (HPGe) detector and a single coaxial HPGe detector to determine the end point energies of nuclear β-decays. The experimental end point energies have been determined for some of the known β-decays in 106Rh →106Pd. The end point energies corresponding to three weak branches in 106Rh →106Pd decay have been measured for the first time. The γ ray and β particle responses for the planar HPGe detector were simulated using the Monte Carlo based code GEANT3. The experimentally obtained β spectra were successfully reproduced with the simulation.

Energy efficiency business options for industrial end users in Latin American competitive energy markets: The case of Colombia

Science.gov (United States)

Botero, Sergio

2002-01-01

Energy markets today in Latin America and worldwide are being restructured from monopolies, either state-owned or privately-owned, to be more openly competitive and incorporate more participation from the private sector. Thus, the schemes that were formerly developed to foster end use energy efficiency are no longer applicable because they were based on mandatory regulations made with political decisions, without sufficiently considering economic feasibility. A consensus exists that the only way energy efficiency could survive in this new paradigm is by being market oriented, giving better services, and additional options to users. However; there is very little information on what end users prefer, and which options would most satisfy customers. Using Colombia as a case study, this research determines and categorizes the energy efficiency business options for large energy end users that can freely participate in the competitive energy market. The energy efficiency market is understood as a market of services aiming to increase efficiency in energy use. These services can be grouped into seven business options. A survey, following the descriptive method, was sent to energy end users in order to determine their preferences for specific energy efficiency business options, as well as the decision-making criteria taken into account for such options. This data was categorized in ten industry groups. As a conclusion, energy efficiency providers should adapt not only to the economic activity or processes of each customer, but also to the potential business options. It was also found that not all industries consider performance contracting as their most preferred option, as a matter of fact, some industries show much higher preference for conventional business options. Among end users, the divergence in option preferences contrasted with the convergence in decision-making criteria. The decision-making criteria "cost-benefit ratio" overwhelmed all other criterion. End users

Beam energy dependence of elliptic flow in heavy-ion collision

International Nuclear Information System (INIS)

Otuka, Naohiko; Isse, Masatsugu; Ohnishi, Akira; Pradip Kumar Sahu; Nara, Yasushi

2002-01-01

We study radial flow and elliptic flow in relativistic heavy-ion collisions at energies from GSI-SIS to BNL-RHIC energies using hadronic cascade model JAM. The excitation function of radial flow shows the softening of hadronic matter from BNL-AGS to CERN-SPS energies. JAM model reproduces transverse mass spectra at BNL-AGS, CERN-SPS at BNL-RHIC energies as well as elliptic flow upto CERN-SPS. For elliptic flow at BNL-RHIC energy (√s=130 GeV), while JAM gives the enough flow at fragment region, it fails at mid rapidity. (author)

The Flow of Energy

Science.gov (United States)

Znidarsic, F.; Robertson, G. A.

In this paper, the flow of energy in materials is presented as mechanical waves with a distinct velocity or speed of transition. This speed of transition came about through the observations of cold fusion experiments, i.e., Low Energy Nuclear Reactions (LENR) and superconductor gravity experiments, both assumed speculative by mainstream science. In consideration of superconductor junctions, the LENR experiments have a similar speed of transition, which seems to imply that the reactions in the LENR experiment are discrete quantized reactions (energy - burst vs. continuous). Here an attempt is made to quantify this new condition as it applies to electrons; toward the progression of quantized energy flows (discrete energy burst) as a new source of clean energy and force mechanisms (i.e, propulsion).

End-user GHG emissions from energy. Reallocation of emissions from energy industries to end users 2005-2009

Energy Technology Data Exchange (ETDEWEB)

Fernandez, R. (European Environment Agency (EEA), Copenhagen (Denmark)); Watterson, J. (AEA Technology plc - EEA' s European Topic Centre on Air Pollution and Climate Change Mitigation (ETC/ACM) (United Kingdom))

2011-12-15

The objective of this report is to help improve the understanding of past greenhouse gas (GHG) emission trends in the energy sector from the demand or end-user side. To do this, the report develops a methodology to redistributes emissions from energy industries to the final users (by sector) of that energy. This reallocation is done on the basis of Eurostat's energy balances and GHG inventories for the energy sector as reported to the United Nations Framework Convention on Climate Change (UNFCCC), for the period 2005-2009. (Author)

End-user GHG emissions from energy. Reallocation of emissions from energy industries to end users 2005-2010

Energy Technology Data Exchange (ETDEWEB)

Fernandez, R. [European Environment Agency (EEA), Copenhagen (Denmark); Watterson, J. [AEA Technology plc - EEA' s European Topic Centre on Air Pollution and Climate Change Mitigation (ETC/ACM) (United Kingdom)

2012-12-15

The objective of this report is to help improve the understanding of past GHG emission trends in the energy sector from the demand or end-user side. To do this, the report develops a methodology to redistributes emissions from energy industries to the final users (by sector) of that energy. This reallocation is done on the basis of Eurostat's energy balances and GHG inventories for the energy sector as reported to the United Nations Framework Convention on Climate Change (UNFCCC), for the period 2005-2010. (Author)

Where to place the saving obligation: Energy end-users or suppliers?

International Nuclear Information System (INIS)

Bertoldi, Paolo; Labanca, Nicola; Rezessy, Silvia; Steuwer, Sibyl; Oikonomou, Vlasis

2013-01-01

Obligations to save energy differentiate, among other features, by obliged parties. These are obligations on energy suppliers and energy end-users. Supplier obligations have been introduced in North America, Europe and Australia. Under supplier obligations energy suppliers have to comply with mandatory energy saving targets and thus they implement (directly or via third parties) energy efficiency projects on their clients’ premises, or they decide to trade certified project savings if this option is envisaged by their obligation scheme. In several emerging schemes such as the UK Carbon Reduction Commitment (CRC) Energy Efficiency Scheme, the Tokyo Emission Trading Scheme or the Perform Achieve and Trade (PAT) Scheme in India, the obligation to reduce energy consumption is placed on large end-users directly and end-users are allowed to trade emissions allowances or energy saving certificates. The paper starts with presenting these two conceptually different ways for introducing energy saving obligations. Then it analyses advantages and disadvantages of end-users obligations compared to suppliers obligations. The preliminary conclusion of the paper is that supplier obligations seem to be well-suited for the residential sector, but end-user saving obligations may offer advantages when it comes to the industrial and commercial sectors. - Highlights: • We present different ways for introducing energy saving obligations. • We analyse energy end-users obligations vs. supplier obligations. • Supplier obligations seem to be well-suited for the residential sector. • End-user obligations offer advantages in the industrial and commercial sectors

Asymmetric energy flow in liquid alkylbenzenes: A computational study

International Nuclear Information System (INIS)

Leitner, David M.; Pandey, Hari Datt

2015-01-01

Ultrafast IR-Raman experiments on substituted benzenes [B. C. Pein et al., J. Phys. Chem. B 117, 10898–10904 (2013)] reveal that energy can flow more efficiently in one direction along a molecule than in others. We carry out a computational study of energy flow in the three alkyl benzenes, toluene, isopropylbenzene, and t-butylbenzene, studied in these experiments, and find an asymmetry in the flow of vibrational energy between the two chemical groups of the molecule due to quantum mechanical vibrational relaxation bottlenecks, which give rise to a preferred direction of energy flow. We compare energy flow computed for all modes of the three alkylbenzenes over the relaxation time into the liquid with energy flow through the subset of modes monitored in the time-resolved Raman experiments and find qualitatively similar results when using the subset compared to all the modes

Novel simplified hourly energy flow models for photovoltaic power systems

International Nuclear Information System (INIS)

Khatib, Tamer; Elmenreich, Wilfried

2014-01-01

Highlights: • We developed an energy flow model for standalone PV system using MATLAB line code. • We developed an energy flow model for hybrid PV/wind system using MATLAB line code. • We developed an energy flow model for hybrid PV/diesel system using MATLAB line code. - Abstract: This paper presents simplified energy flow models for photovoltaic (PV) power systems using MATLAB. Three types of PV power system are taken into consideration namely standalone PV systems, hybrid PV/wind systems and hybrid PV/diesel systems. The logic of the energy flow for each PV power system is discussed first and then the MATLAB line codes for these models are provided and explained. The results prove the accuracy of the proposed models. Such models help modeling and sizing PV systems

End-of-life flows of multiple cycle consumer products

International Nuclear Information System (INIS)

Tsiliyannis, C.A.

2011-01-01

Explicit expressions for the end-of-life flows (EOL) of single and multiple cycle products (MCPs) are presented, including deterministic and stochastic EOL exit. The expressions are given in terms of the physical parameters (maximum lifetime, T, annual cycling frequency, f, number of cycles, N, and early discard or usage loss). EOL flows are also obtained for hi-tech products, which are rapidly renewed and thus may not attain steady state (e.g. electronic products, passenger cars). A ten-step recursive procedure for obtaining the dynamic EOL flow evolution is proposed. Applications of the EOL expressions and the ten-step procedure are given for electric household appliances, industrial machinery, tyres, vehicles and buildings, both for deterministic and stochastic EOL exit, (normal, Weibull and uniform exit distributions). The effect of the physical parameters and the stochastic characteristics on the EOL flow is investigated in the examples: it is shown that the EOL flow profile is determined primarily by the early discard dynamics; it also depends strongly on longevity and cycling frequency: higher lifetime or early discard/loss imply lower dynamic and steady state EOL flows. The stochastic exit shapes the overall EOL dynamic profile: Under symmetric EOL exit distribution, as the variance of the distribution increases (uniform to normal to deterministic) the initial EOL flow rise becomes steeper but the steady state or maximum EOL flow level is lower. The steepest EOL flow profile, featuring the highest steady state or maximum level, as well, corresponds to skew, earlier shifted EOL exit (e.g. Weibull). Since the EOL flow of returned products consists the sink of the reuse/remanufacturing cycle (sink to recycle) the results may be used in closed loop product lifecycle management operations for scheduling and sizing reverse manufacturing and for planning recycle logistics. Decoupling and quantification of both the full age EOL and of the early discard flows is

Measurement of β-decay end point energy with planar HPGe detector

Energy Technology Data Exchange (ETDEWEB)

Bhattacharjee, T., E-mail: btumpa@vecc.gov.in [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Pandit, Deepak [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Das, S.K. [RCD-BARC, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Chowdhury, A.; Das, P. [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Banerjee, D. [RCD-BARC, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Saha, A.; Mukhopadhyay, S.; Pal, S.; Banerjee, S.R. [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India)

2014-12-11

The β–γ coincidence measurement has been performed with a segmented planar Hyper-Pure Germanium (HPGe) detector and a single coaxial HPGe detector to determine the end point energies of nuclear β-decays. The experimental end point energies have been determined for some of the known β-decays in {sup 106}Rh→{sup 106}Pd. The end point energies corresponding to three weak branches in {sup 106}Rh→{sup 106}Pd decay have been measured for the first time. The γ ray and β particle responses for the planar HPGe detector were simulated using the Monte Carlo based code GEANT3. The experimentally obtained β spectra were successfully reproduced with the simulation.

Energy flow theory of nonlinear dynamical systems with applications

CERN Document Server

Xing, Jing Tang

2015-01-01

This monograph develops a generalised energy flow theory to investigate non-linear dynamical systems governed by ordinary differential equations in phase space and often met in various science and engineering fields. Important nonlinear phenomena such as, stabilities, periodical orbits, bifurcations and chaos are tack-led and the corresponding energy flow behaviors are revealed using the proposed energy flow approach. As examples, the common interested nonlinear dynamical systems, such as, Duffing’s oscillator, Van der Pol’s equation, Lorenz attractor, Rössler one and SD oscillator, etc, are discussed. This monograph lights a new energy flow research direction for nonlinear dynamics. A generalised Matlab code with User Manuel is provided for readers to conduct the energy flow analysis of their nonlinear dynamical systems. Throughout the monograph the author continuously returns to some examples in each chapter to illustrate the applications of the discussed theory and approaches. The book can be used as ...

Low energy consumption vortex wave flow membrane bioreactor.

Science.gov (United States)

Wang, Zhiqiang; Dong, Weilong; Hu, Xiaohong; Sun, Tianyu; Wang, Tao; Sun, Youshan

2017-11-01

In order to reduce the energy consumption and membrane fouling of the conventional membrane bioreactor (MBR), a kind of low energy consumption vortex wave flow MBR was exploited based on the combination of biofilm process and membrane filtration process, as well as the vortex wave flow technique. The experimental results showed that the vortex wave flow state in the membrane module could be formed when the Reynolds number (Re) of liquid was adjusted between 450 and 1,050, and the membrane flux declined more slowly in the vortex wave flow state than those in the laminar flow state and turbulent flow state. The MBR system was used to treat domestic wastewater under the condition of vortex wave flow state for 30 days. The results showed that the removal efficiency for CODcr and NH 3 -N was 82% and 98% respectively, and the permeate quality met the requirement of 'Water quality standard for urban miscellaneous water consumption (GB/T 18920-2002)'. Analysis of the energy consumption of the MBR showed that the average energy consumption was 1.90 ± 0.55 kWh/m 3 (permeate), which was only two thirds of conventional MBR energy consumption.

Three-dimensional fluid flow phenomena in the blade end wall corner region

Science.gov (United States)

Hazarika, B. K.; Raj, R.; Boldman, D. R.

1986-01-01

Flow visualization, static and total pressure measurements, and mean velocity profile measurements with a single-sensor inclined hot wire probe, are used in a study of three-dimensional flow at a turbine blade end wall corner region for six critical axial stations along the blade chord. Three vortices are identified: (1) a horseshoe vortex near the leading edge; (2) a corner eddy between the horseshoe vortex and the corner; and (3) a vortex at the rear portion of the corner due to the corner eddy's secondary flow. Attention is given to the relative size and rate-of-spread of the vortices in the streamwise direction.

Flow design and simulation of a gas compression system for hydrogen fusion energy production

Energy Technology Data Exchange (ETDEWEB)

Avital, E J; Salvatore, E [School of Engineering and Materials Science, Queen Mary University of London, Mile End Rd London E1 4NS (United Kingdom); Munjiza, A [Civil Engineering, University of Split, Livanjska 2100 Split (Croatia); Suponitsky, V; Plant, D; Laberge, M, E-mail: e.avital@qmul.ac.uk [General Fusion Inc.,108-3680 Bonneville Place, Burnaby, BC V3N 4T5 (Canada)

2017-08-15

An innovative gas compression system is proposed and computationally researched to achieve a short time response as needed in engineering applications such as hydrogen fusion energy reactors and high speed hammers. The system consists of a reservoir containing high pressure gas connected to a straight tube which in turn is connected to a spherical duct, where at the sphere’s centre plasma resides in the case of a fusion reactor. Diaphragm located inside the straight tube separates the reservoir’s high pressure gas from the rest of the plenum. Once the diaphragm is breached the high pressure gas enters the plenum to drive pistons located on the inner wall of the spherical duct that will eventually end compressing the plasma. Quasi-1D and axisymmetric flow formulations are used to design and analyse the flow dynamics. A spike is designed for the interface between the straight tube and the spherical duct to provide a smooth geometry transition for the flow. Flow simulations show high supersonic flow hitting the end of the spherical duct, generating a return shock wave propagating upstream and raising the pressure above the reservoir pressure as in the hammer wave problem, potentially giving temporary pressure boost to the pistons. Good agreement is revealed between the two flow formulations pointing to the usefulness of the quasi-1D formulation as a rapid solver. Nevertheless, a mild time delay in the axisymmetric flow simulation occurred due to moderate two-dimensionality effects. The compression system is settled down in a few milliseconds for a spherical duct of 0.8 m diameter using Helium gas and a uniform duct cross-section area. Various system geometries are analysed using instantaneous and time history flow plots. (paper)

Flow design and simulation of a gas compression system for hydrogen fusion energy production

Science.gov (United States)

Avital, E. J.; Salvatore, E.; Munjiza, A.; Suponitsky, V.; Plant, D.; Laberge, M.

2017-08-01

An innovative gas compression system is proposed and computationally researched to achieve a short time response as needed in engineering applications such as hydrogen fusion energy reactors and high speed hammers. The system consists of a reservoir containing high pressure gas connected to a straight tube which in turn is connected to a spherical duct, where at the sphere’s centre plasma resides in the case of a fusion reactor. Diaphragm located inside the straight tube separates the reservoir’s high pressure gas from the rest of the plenum. Once the diaphragm is breached the high pressure gas enters the plenum to drive pistons located on the inner wall of the spherical duct that will eventually end compressing the plasma. Quasi-1D and axisymmetric flow formulations are used to design and analyse the flow dynamics. A spike is designed for the interface between the straight tube and the spherical duct to provide a smooth geometry transition for the flow. Flow simulations show high supersonic flow hitting the end of the spherical duct, generating a return shock wave propagating upstream and raising the pressure above the reservoir pressure as in the hammer wave problem, potentially giving temporary pressure boost to the pistons. Good agreement is revealed between the two flow formulations pointing to the usefulness of the quasi-1D formulation as a rapid solver. Nevertheless, a mild time delay in the axisymmetric flow simulation occurred due to moderate two-dimensionality effects. The compression system is settled down in a few milliseconds for a spherical duct of 0.8 m diameter using Helium gas and a uniform duct cross-section area. Various system geometries are analysed using instantaneous and time history flow plots.

ECAL Energy Flow Calibration

CERN Multimedia

CERN. Geneva

2015-01-01

My talk will be covering my work as a whole over the course of the semester. The focus will be on using energy flow calibration in ECAL to check the precision of the corrections made by the light monitoring system used to account for transparency loss within ECAL crystals due to radiation damage over time.

Energy sources consumption: end uses, efficiency and productivity; La consommation des sources d'energie: utilisations finales, efficacite et productivite

Energy Technology Data Exchange (ETDEWEB)

Martin, J.M. [Institut d' Economie et de Politique de l' Energie (CNRS- UPMF), 38 - Grenoble (France)

2005-07-01

This document analyzes the impact of the choices made by all actors, from the energy producers to the process and infrastructure designers and the end users, in the evolution of energy consumptions. Some very little improvements made in the energy efficiency of appliances can become equivalent to the production of several oil fields or power plants at the world scale. More efficient energy uses will not replace the additional productions but they must be considered together to be compared. The energy files are first analyzed as a whole in order to show the hidden field of energy choices. In this framework, users, designers and fitters have to face very different choices because they consider efficiency improvements under different aspects: scientifical, technical, economical and social (public information and habits). These differences in efficiency uses have a time and spatial impact on the growth of energy consumption. The economical and social factors influence the collective way to consume energy and are expressed by the energy intensity of the economic activity. The last part of this document analyzes the influence of this notion on the world energy consumption scenarios at the 2050 prospects. (J.S.)

Multiphase Venturi Dual Energy Gamma Ray combination performance in NUEX flow loop; Desempenho no flowloop do NUEX da medicao multifasica Venturi Dual Energy Gamma Ray

Energy Technology Data Exchange (ETDEWEB)

Barreiros, Claudio; Taranto, Cleber; Costa, Alcemir [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Pinguet, Bruno; Heluey, Vitor; Bessa, Fabiano; Loicq, Olivier [Schlumberger Servicos de Petroleo Ltda., Rio de Janeiro, RJ (Brazil)

2008-07-01

The Multiphase Venturi Dual Energy Gamma Ray Combination, Vx* technology, arrived in Brazil in 2000. PETROBRAS, Brazilian Oil Company, has been putting big efforts in its production business and also has demonstrated a large interest in having a multiphase meter approved by ANP for back allocation purposes. The oil industry was looking for ways to improve the back allocation process using an approved on line multiphase flow measurement device, thus replacing punctual test done today by a permanent monitoring device. Considering this scenario, a partnership project between PETROBRAS and Schlumberger was created in Brazil. The main objective of this project, which was held in NUEX flow loop, was to demonstrate to INMETRO (Brazilian Metrology Institute) that the Multiphase Venturi Dual Energy Gamma Ray Combination meter is able to be used for back allocation purpose. PETROBRAS and Schlumberger elaborated a complete methodology in the NUEX flow loop to demonstrate the results and benefits of the Multiphase Venturi Dual Energy Gamma Ray Combination meter. The test was witnessed by INMETRO and had a very good performance at the end. The results were within what was expected by Schlumberger, PETROBRAS and INMETRO. These results has been very useful to PETROBRAS in order to start using the Venturi Dual Energy Gamma Ray technology for well allocation purposes. (author)

End-Use Efficiency to Lower Carbon Emissions

International Nuclear Information System (INIS)

Marnay, Chris; Osborn, Julie; Webber, Carrie

2001-01-01

Compelling evidence demonstrating the warming trend in global temperatures and the mechanism behind it, namely the anthropogenic emissions of carbon dioxide and other greenhouse gases (GHG), has spurred an international effort to reduce emissions of these gases. Despite improving efficiency of the U.S. economy in terms of energy cost per dollar of GDP since the signing of the Kyoto Protocol, energy consumption and carbon emissions are continuing to rise as the economy expands. This growing gap further emphasizes the importance of improving energy use efficiency as a component in the U.S. climate change mitigation program. The end-use efficiency research activities at Berkeley Lab incorporate residential, commercial, industrial, and transportation sectors. This paper focuses on two successful U.S. programs that address end-use efficiency in residential and commercial demand: energy efficient performance standards established by the Department of Energy (DOE) and the Environmental Protection Agency's (EPA's) ENERGY STAR(registered trademark) program

Concepts for dynamic modelling of energy-related flows in manufacturing

International Nuclear Information System (INIS)

Wright, A.J.; Oates, M.R.; Greenough, R.

2013-01-01

Highlights: ► Modelling of the thermal flows in factories and processes is usually separate. ► We propose a set of key features for an integrated thermal model. ► Such models can be used to improve the efficiency of manufacturing processes. - Abstract: Industry uses around one third of the world’s energy, and accounts for about 40% of global carbon dioxide emissions. There is increasing economic and social pressure to improve efficiency and create closed-loop industrial systems, in which energy efficiency plays a key role. This paper describes some of the key concepts involved in modelling the energy flows in manufacturing, both for the building services and the industrial processes. Detailed dynamic energy simulation of buildings is well established and routinely used, working on a time series basis – but current tools are inadequate to model the energy flows of many industrial processes. There are also well-established models of manufacturing flows, used to optimise production efficiency, but typically not modelling energy, and usually representing production and material flows as event-driven processes. The THERM project has developed new software tools to model energy-related and other utility flows in manufacturing, incorporating these into existing thermal models of factory buildings. This makes it possible to map out the whole energy system, and hence to test efficiency measures, to understand the effect of processes on building energy use, to investigate recycling of heat or cooling into other processes or building conditioning, and so on. The paper describes some of the key concepts and modelling approaches involved in developing these models, and gives examples of some real processes modelled in factories. It concludes that such models are entirely feasible and potentially very useful, although to develop a tool which comprehensively models both energy and manufacturing flows would be a major undertaking

Material and energy flows in the materials production, assembly, and end-of-life stages of the automotive lithium-ion battery life cycle

Energy Technology Data Exchange (ETDEWEB)

Dunn, J.B.; Gaines, L.; Barnes, M.; Wang, M.; Sullivan, J. (Energy Systems)

2012-06-21

This document contains material and energy flows for lithium-ion batteries with an active cathode material of lithium manganese oxide (LiMn{sub 2}O{sub 4}). These data are incorporated into Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, replacing previous data for lithium-ion batteries that are based on a nickel/cobalt/manganese (Ni/Co/Mn) cathode chemistry. To identify and determine the mass of lithium-ion battery components, we modeled batteries with LiMn{sub 2}O{sub 4} as the cathode material using Argonne's Battery Performance and Cost (BatPaC) model for hybrid electric vehicles, plug-in hybrid electric vehicles, and electric vehicles. As input for GREET, we developed new or updated data for the cathode material and the following materials that are included in its supply chain: soda ash, lime, petroleum-derived ethanol, lithium brine, and lithium carbonate. Also as input to GREET, we calculated new emission factors for equipment (kilns, dryers, and calciners) that were not previously included in the model and developed new material and energy flows for the battery electrolyte, binder, and binder solvent. Finally, we revised the data included in GREET for graphite (the anode active material), battery electronics, and battery assembly. For the first time, we incorporated energy and material flows for battery recycling into GREET, considering four battery recycling processes: pyrometallurgical, hydrometallurgical, intermediate physical, and direct physical. Opportunities for future research include considering alternative battery chemistries and battery packaging. As battery assembly and recycling technologies develop, staying up to date with them will be critical to understanding the energy, materials, and emissions burdens associated with batteries.

Material and Energy Flows in the Materials Production, Assembly, and End-of-Life Stages of the Automotive Lithium-Ion Battery Life Cycle

Energy Technology Data Exchange (ETDEWEB)

Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States); Gaines, Linda [Argonne National Lab. (ANL), Argonne, IL (United States); Barnes, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States); Sullivan, John L. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

2014-01-01

This document contains material and energy flows for lithium-ion batteries with an active cathode material of lithium manganese oxide (LiMn₂O₄). These data are incorporated into Argonne National Laboratory’s Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, replacing previous data for lithium-ion batteries that are based on a nickel/cobalt/manganese (Ni/Co/Mn) cathode chemistry. To identify and determine the mass of lithium-ion battery components, we modeled batteries with LiMn₂O₄ as the cathode material using Argonne’s Battery Performance and Cost (BatPaC) model for hybrid electric vehicles, plug-in hybrid electric vehicles, and electric vehicles. As input for GREET, we developed new or updated data for the cathode material and the following materials that are included in its supply chain: soda ash, lime, petroleum-derived ethanol, lithium brine, and lithium carbonate. Also as input to GREET, we calculated new emission factors for equipment (kilns, dryers, and calciners) that were not previously included in the model and developed new material and energy flows for the battery electrolyte, binder, and binder solvent. Finally, we revised the data included in GREET for graphite (the anode active material), battery electronics, and battery assembly. For the first time, we incorporated energy and material flows for battery recycling into GREET, considering four battery recycling processes: pyrometallurgical, hydrometallurgical, intermediate physical, and direct physical. Opportunities for future research include considering alternative battery chemistries and battery packaging. As battery assembly and recycling technologies develop, staying up to date with them will be critical to understanding the energy, materials, and emissions burdens associated with batteries.

Gran method for end point anticipation in monosegmented flow titration

Directory of Open Access Journals (Sweden)

Aquino Emerson V

2004-01-01

Full Text Available An automatic potentiometric monosegmented flow titration procedure based on Gran linearisation approach has been developed. The controlling program can estimate the end point of the titration after the addition of three or four aliquots of titrant. Alternatively, the end point can be determined by the second derivative procedure. In this case, additional volumes of titrant are added until the vicinity of the end point and three points before and after the stoichiometric point are used for end point calculation. The performance of the system was assessed by the determination of chloride in isotonic beverages and parenteral solutions. The system employs a tubular Ag2S/AgCl indicator electrode. A typical titration, performed according to the IUPAC definition, requires only 60 mL of sample and about the same volume of titrant (AgNO3 solution. A complete titration can be carried out in 1 - 5 min. The accuracy and precision (relative standard deviation of ten replicates are 2% and 1% for the Gran and 1% and 0.5% for the Gran/derivative end point determination procedures, respectively. The proposed system reduces the time to perform a titration, ensuring low sample and reagent consumption, and full automatic sampling and titrant addition in a calibration-free titration protocol.

Energy Harvesting Characteristics from Water Flow by Piezoelectric Energy Harvester Device Using Cr/Nb Doped Pb(Zr,Ti)O3 Bimorph Cantilever

Science.gov (United States)

Kim, Kyoung-Bum; Kim, Chang Il; Jeong, Young Hun; Cho, Jeong-Ho; Paik, Jong-Hoo; Nahm, Sahn; Lim, Jong Bong; Seong, Tae-Hyeon

2013-10-01

A water flow energy harvester, which can convert water flow energy to electric energy, was fabricated for its application to rivers. This harvester can generate power from the bending and releasing motion of piezoelectric bimorph cantilevers. A Pb(Zr0.54Ti0.46)O3 + 0.2 wt % Cr2O3 + 1.0 wt % Nb2O5 (PZT-CN) thick film and a 250-µm-thick stainless steel were used as a bimorph cantilever. The electrical impedance matching was achieved across a resistive load of 1 kΩ. Four bimorph cantilevers can generate power from 5 to 105 rpm. The output powers were steadily increased by increasing the rpm. The maximum output power was 68 mW by 105 rpm. It was found that the water flow energy harvester can generate 58 mW by a flow velocity of (2 m/s) from the stream with the four bimorph cantilevers.

Flow energy piezoelectric bimorph nozzle harvester

Science.gov (United States)

Sherrit, Stewart; Lee, Hyeong Jae; Walkemeyer, Phillip; Hasenoehrl, Jennifer; Hall, Jeffrey L.; Colonius, Tim; Tosi, Luis Phillipe; Arrazola, Alvaro; Kim, Namhyo; Sun, Kai; Corbett, Gary

2014-04-01

There is a need for a long-life power generation scheme that could be used downhole in an oil well to produce 1 Watt average power. There are a variety of existing or proposed energy harvesting schemes that could be used in this environment but each of these has its own limitations. The vibrating piezoelectric structure is in principle capable of operating for very long lifetimes (decades) thereby possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. In order to determine the feasibility of using piezoelectrics to produce suitable flow energy harvesting, we surveyed experimentally a variety of nozzle configurations that could be used to excite a vibrating piezoelectric structure in such a way as to enable conversion of flow energy into useful amounts of electrical power. These included reed structures, spring mass-structures, drag and lift bluff bodies and a variety of nozzles with varying flow profiles. Although not an exhaustive survey we identified a spline nozzle/piezoelectric bimorph system that experimentally produced up to 3.4 mW per bimorph. This paper will discuss these results and present our initial analyses of the device using dimensional analysis and constitutive electromechanical modeling. The analysis suggests that an order-of-magnitude improvement in power generation from the current design is possible.

Modelling and study on the output flow characteristics of expansion energy used hydropneumatic transformer

Energy Technology Data Exchange (ETDEWEB)

Shi, Yan; Wu, Tiecheng; Cai, Maolin; Liu, Chong [Beihang University, Beijing (China)

2016-03-15

Hydropneumatic transformer (short for HP transformer) is used to pump pressurized hydraulic oil. Whereas, due to its insufficient usage of energy and low efficiency, a new kind of HP transformer: EEUHP transformer (Expansion energy used hydropneumatic transformer) was proposed. To illustrate the characteristics of the EEUHP transformer, a mathematical model was built. To verify the mathematical model, an experimental prototype was setup and studied. Through simulation and experimental study on the EEUHP transformer, the influence of five key parameters on the output flow of the EEUHP transformer were obtained, and some conclusions can be drawn. Firstly, the mathematical model was proved to be valid. Furthermore, the EEUHP transformer costs fewer of compressed air than the normal HP transformer when the output flow of the two kinds of transformers are almost same. Moreover, with an increase in the output pressure, the output flow decreases sharply. Finally, with an increase in the effective area of hydraulic output port, the output flow increases distinctly. This research can be referred to in the performance and design optimization of the EEUHP transformers.

Effect of material flows on energy intensity in process industries

Energy Technology Data Exchange (ETDEWEB)

Liu, Liru; Aye, Lu [International Technologies Center (IDTC), Department of Civil and Environmental Engineering, The University of Melbourne, Victoria 3010 (Australia); Lu, Zhongwu [Institute of Materials and Metallurgy, Northeastern University, Shenyang 110004 (China); Zhang, Peihong [Department of Municipal and Environmental Engineering, Shenyang Architecture University, Shenyang 110168 (China)

2006-09-15

Many energy-intensive process industries have complex material flows, which have a strong effect on the overall energy intensity of the final product (OEIF). This problem, however, has only been recognised qualitatively due to the lack of quantitative analysis methods. This paper presents an in-depth quantitative analysis of the effect of material flows on energy intensity in process industries. Based on the concept of a standard material flow diagram (SMFD), as used in steel manufacturing, the SMFD for a generic process industry was first developed. Then material flow scenarios were addressed in a practical material flow diagram (PMFD) using the characteristics of practical process industries. The effect of each material flow deviating from a SMFD on the OEIF was analysed. The steps involved in analysing the effect of material flows in a PMFD on its energy intensity are also discussed in detail. Finally, using 1999 statistical data from the Chinese Zhenzhou alumina refinery plant, the PMFD and SMFD for this plant were constructed as a case study. The effect of material flows on the overall energy intensity of alumina (OEIA) was thus analysed quantitatively. To decrease OEIA, the process variations which decrease the product ratios could be employed in all except in multi-supplied fraction cases. In these cases, the fractions from the stream with lower energy intensities should be increased. (author)

Energy flows of the biosphere

Energy Technology Data Exchange (ETDEWEB)

Gorshkov, V.G.

1980-01-01

Mankind consumes more than 90% of the animal production of the world. The locking of a significant part of the biosphere energy flow onto the anthropogenic chain leads to the dislodging of natural forms of organisms of the biosphere, change of its functioning and self-regulation. For the maintenance of stable existence of a small set of cultivated plants and domestic animals not forming the complete set indispensable for reaction to the change of natural conditions, man is compelled to follow the path of auxiliary investments of energy and to compensate for the destruction of closed circulations of food substances by the flow of fertilizers extracted from natural deposits. Energy assessments show the lack of realism of many projects for increasing the global energy flow in the anthropogenic channel by increasing the full flow of energy of the biosphere. To obtain the net production of the contemporary plowed field in hotbed on the basis of hydroponics there is required 2 x 10/sup 14/ watts of additional energy. To provide for the inflow of such an amount of energy (and also vast volumes of fresh water) presents extremely complicated problems. According to the author's calculations, in a provisional conversion of all production of green plants, all gas and petroleum and edible food with an efficiency equal to 1%, it is possible to provide food reserves equal to one annual harvest of the plowed fields of the world of 2 x 10/sup 9/ tons.

Effects of Low-Carbon Technologies and End-Use Electrification on Energy-Related Greenhouse Gases Mitigation in China by 2050

Directory of Open Access Journals (Sweden)

Zheng Guo

2015-07-01

Full Text Available Greenhouse gas emissions in China have been increasing in line with its energy consumption and economic growth. Major means for energy-related greenhouse gases mitigation in the foreseeable future are transition to less carbon intensive energy supplies and structural changes in energy consumption. In this paper, a bottom-up model is built to examine typical projected scenarios for energy supply and demand, with which trends of energy-related carbon dioxide emissions by 2050 can be analyzed. Results show that low-carbon technologies remain essential contributors to reducing emissions and altering emissions trends up to 2050. By pushing the limit of current practicality, emissions reduction can reach 20 to 28 percent and the advent of carbon peaking could shift from 2040 to 2030. In addition, the effect of electrification at end-use sectors is studied. Results show that electrifying transport could reduce emissions and bring the advent of carbon peaking forward, but the effect is less significant compared with low-carbon technologies. Moreover, it implies the importance of decarbonizing power supply before electrifying end-use sectors.

Free surface profiles in river flows: Can standard energy-based gradually-varied flow computations be pursued?

Science.gov (United States)

Cantero, Francisco; Castro-Orgaz, Oscar; Garcia-Marín, Amanda; Ayuso, José Luis; Dey, Subhasish

2015-10-01

Is the energy equation for gradually-varied flow the best approximation for the free surface profile computations in river flows? Determination of flood inundation in rivers and natural waterways is based on the hydraulic computation of flow profiles. This is usually done using energy-based gradually-varied flow models, like HEC-RAS, that adopts a vertical division method for discharge prediction in compound channel sections. However, this discharge prediction method is not so accurate in the context of advancements over the last three decades. This paper firstly presents a study of the impact of discharge prediction on the gradually-varied flow computations by comparing thirteen different methods for compound channels, where both energy and momentum equations are applied. The discharge, velocity distribution coefficients, specific energy, momentum and flow profiles are determined. After the study of gradually-varied flow predictions, a new theory is developed to produce higher-order energy and momentum equations for rapidly-varied flow in compound channels. These generalized equations enable to describe the flow profiles with more generality than the gradually-varied flow computations. As an outcome, results of gradually-varied flow provide realistic conclusions for computations of flow in compound channels, showing that momentum-based models are in general more accurate; whereas the new theory developed for rapidly-varied flow opens a new research direction, so far not investigated in flows through compound channels.

Putting an end to nuclear energy: why and how

International Nuclear Information System (INIS)

Dessus, Benjamin; Laponche, Bernard

2011-01-01

This short book demonstrates the necessity and possibility to put an end to nuclear energy. First, it sweeps away the fallacious reasoning of nuclear supporters, like the energy independence, the safety and security aspects, the electricity cost, the greenhouse gases abatement. Then, it replaces the ending of nuclear energy in the more general framework of a worldwide energy transition, with its constraints and risks, which has become a necessity considering the geographical disparities of energy consumption. According to the author, the particular energy situation of France would lead the country to isolation and to an energy impasse while other worldwide and regional scenarios exist which would lead to exit the crisis and to reach a new energy civilization. Finally, a reasoned scenario of nuclear energy exit is proposed for France which is based on other power generation means. Such an energy transition will require some political and social conditions which are discussed. (J.S.)

Flow visualization study of two-phase flow in the horizontal annulus of the fuel-channel outlet end-fitting of a CANDU reactor

International Nuclear Information System (INIS)

Supa-Amornkul, S.; Steward, F.R.; Lister, D.H.

2005-01-01

In CANDU-6 reactors, the pressurized hightemperature coolant flows through 380 fuel channels passing horizontally through the core. In 1996, higher than expected rates of wall thinning of the outlet feeders were ascribed to flow-accelerated corrosion (FAC). Such corrosion is strongly influenced by the hydrodynamics of the coolant. Results of preliminary flow visualization and modelling studies have suggested that flow conditions in the end-fitting annulus upstream of the outlet feeder may influence the pattern of FAC. For a full-scale flow visualization, an acrylic test section was built to simulate the cylindrical end-fitting with its annulus flow path. The tests were performed with water and air at atmospheric pressure and room temperature. The phase distribution along the length of the annulus was recorded with a digital video recorder. Size, concentration and velocity of the air bubbles at particular locations were studied with a high-speed digital still camera and a high-speed digital video camera. Phase distributions and variations in bubble size with velocity were determined. Significant effects on the flow patterns of spacer buttons in the annulus were observed. A commercial computational fluid dynamics (CFD) code-Fluent 6.1-was used to model the results. (authors)

Effect of breathing fluctuations on cerebral blood flow in demented patients and its correction method using end-tidal CO/sub 2/ concentration

Energy Technology Data Exchange (ETDEWEB)

Komatani, Akio; Yamaguchi, Koichi; Kera, Masahiro; Takanashi, Toshiyasu; Shinohara, Masao; Kawakatsu, Shinobu; Yazaki, Mitsuyasu

1989-02-01

During mouthpiece respiration of Xe-133 for a measurement of regional cerebral blood flow (rCBF), the breathing pattern of patients fluctuated and it caused a change of end-tidal CO/sub 2/ concentration that had an excellent correlation with PaCO/sub 2/ in patients without respiratory disease. The end-tidal CO/sub 2/ concentration of demented patients varied within lower ranges than senile control group. The range of fluctuation on the end-tidal CO/sub 2/ concentration was dependent on the type and the degree of dementia, and it fluctuated most widely at the middle stage of Alzheimer disease. Mean cerebral blood flow increased by 13.9% for each l% increase in end-tidal CO/sub 2/ concentration (3.6%/mmHg PaCO/sub 2/) in the case of demented patients without cerebrovascular disease. To improve the reliability of rCBF in demented patients, especially in Alzheimer disease, the correction of rCBF data for end-tidal CO/sub 2/ concentration should be performed.

A PROTOTYPICAL HYDRODYNAMIC MINI GENERATOR OF ELECTRIC ENERGY TO BE USED IN THE CHANNEL FLOW

Directory of Open Access Journals (Sweden)

Roman KACZYŃSKI

2014-03-01

Full Text Available This work presents the numerical analysis and scientific research of prototypical solutions for mini generators of electric energy to be assembled in small diameter pipelines. Additionally, this papers presents the construction of a test stand stimulating similar flow to the actual flow allowing testing various geometry of impellers at variable conditions. In order to optimize the impellers geometry of hydro generators the cfd analysis has been used. The characteristics of miniature stepper motors working as electric energy generators have also been assigned.

Methodology for getting the end use of energy in the industrial sector from Parana State

International Nuclear Information System (INIS)

Haag Filho, A.

1990-03-01

A methodology for a survey on the utilization of energy in the industrial sector from Parana state, at low costs, and aiming the supply of data with the desired reliability and disaggregation is presented. The obtained data shall provide elements for the adoption of short term actions as well as serve as a basis for the elaboration of medium and long terms scenarios. The survey shall be conducted throughout the state, comprising all fields of activity and having the following objectives: determine the state's energetic consumption profile by industrial segment and by end use of energy; determine the state's energetic profile with the spatial distribution of consumption and detect the industrial segments which are more sensitive to the energetic substitution programs and/or of energy conservation. (author)

Use of material flow accounting for assessment of energy savings: A case of biomass in Slovakia and the Czech Republic

International Nuclear Information System (INIS)

Kanianska, Radoslava; Gustafikova, Tatiana; Kizekova, Miriam; Kovanda, Jan

2011-01-01

Anthropogenic material and energy flows are considered to be the major cause of many environmental problems humans face today. In order to measure material and energy flows, and to mitigate related problems, the technique of material flow and energy flow analysis has been conceived. The aim of this article is to use material and energy flow accounting approaches to quantify the amount of biomass that is available, but that so far has not been used for energy purposes in Slovakia and the Czech Republic and to calculate how much consumed fossil fuels and corresponding CO 2 emissions can be saved by utilising this biomass. Based on the findings presented, 3544 kt/yr of the total unused biomass in Slovakia could replace 53 PJ/yr of energy from fossil fuels and 6294 kt/yr of the total unused biomass in the Czech Republic could replace 91 PJ/yr of energy. Such replacement could contribute to a decrease in total CO 2 emissions by 9.2% in Slovakia and by 5.4% in the Czech Republic and thus contribute to an environmental improvement with respect to climate change. - Research highlights: → The material and energy flow accounting approaches for biomass were applied. → In Slovakia, 3544 kt/yr of the total unused biomass is available. → In the Czech Republic, 6294 kt/yr of the total unused biomass is available. → Such biomass could be used for energy production and thus reduce CO 2 emissions.

Erosion estimation of guide vane end clearance in hydraulic turbines with sediment water flow

Science.gov (United States)

Han, Wei; Kang, Jingbo; Wang, Jie; Peng, Guoyi; Li, Lianyuan; Su, Min

2018-04-01

The end surface of guide vane or head cover is one of the most serious parts of sediment erosion for high-head hydraulic turbines. In order to investigate the relationship between erosion depth of wall surface and the characteristic parameter of erosion, an estimative method including a simplified flow model and a modificatory erosion calculative function is proposed in this paper. The flow between the end surfaces of guide vane and head cover is simplified as a clearance flow around a circular cylinder with a backward facing step. Erosion characteristic parameter of csws3 is calculated with the mixture model for multiphase flow and the renormalization group (RNG) k-𝜀 turbulence model under the actual working conditions, based on which, erosion depths of guide vane and head cover end surfaces are estimated with a modification of erosion coefficient K. The estimation results agree well with the actual situation. It is shown that the estimative method is reasonable for erosion prediction of guide vane and can provide a significant reference to determine the optimal maintenance cycle for hydraulic turbine in the future.

Flood Risk Mapping Using Flow Energy Equation and Geographic Information System

Directory of Open Access Journals (Sweden)

pourya Javan

2013-09-01

Full Text Available Flooding and its damages are not only found uplift water level in a region. In other words, the depth and speed parameters together have determining the level of flood risk at each point. This subject is visible in flooded plain with low height and high speed of 2 meters per second, which damages are extensive. According to the criteria of having both velocity and flow depth in the governing equation to the flows energy, this equation seems appropriate to analysis in this study. Various methods have been proposed for increase accuracy in flood zoning with different return periods and risks associated with it in land border of river. For example, some of these methods are considered factors such as analysis of past flooding in the area affected by floods, hydrological factors and consideration of hydraulic elements affecting in flood zoning (such as flow velocity. This paper investigates the effect of flood zoning by the energy flow in the areas affected by floods. Also risk due to flood based on energy flow in each section of the river is compared by the proposed graphs of hazard interval and other done flood zoning in this field. In this study, the FORDO river has been selected as the case study. This river is part of the rivers located in the city of QOM KAHAK. The characteristics of river in upstream and downstream are mountain, young and stable and adult, respectively. Also this river in different seasons is exposed the flood damage. The proposed method in this study can be improving recognition accuracy of flood risk in areas affected by flood. Also, this method facilitate the identify parts of the river bed, that is affected by severe flooding, for decision making to improve rivers organizing.

Updating the Slovak strategy of back-end of peaceful use of nuclear energy

International Nuclear Information System (INIS)

Salzer, P.; Timulak, J.

2010-01-01

In this work authors present the Slovak strategy of back-end of peaceful use of nuclear energy. Slovak Government approved the Strategy by Governmental decision No. 328/2008 in May 21, 2008. Decree of the Government solves the problem of historical debt by payments of operators of the electricity transmission network and of the distribution network, according the provisions of the Act on the National Nuclear Fund. Financing of the management of institutional radioactive waste after its centralized collection performed by JAVYS, a.s. Economic aspects of reactors decommissioning as well as the sources of financing are presented.

Energy fluxes and spectra for turbulent and laminar flows

KAUST Repository

Verma, Mahendra K.

2017-05-14

Two well-known turbulence models to describe the inertial and dissipative ranges simultaneously are by Pao~[Phys. Fluids {\\\\bf 8}, 1063 (1965)] and Pope~[{\\\\em Turbulent Flows.} Cambridge University Press, 2000]. In this paper, we compute energy spectrum $E(k)$ and energy flux $\\\\Pi(k)$ using spectral simulations on grids up to $4096^3$, and show consistency between the numerical results and predictions by the aforementioned models. We also construct a model for laminar flows that predicts $E(k)$ and $\\\\Pi(k)$ to be of the form $\\\\exp(-k)$, and verify the model predictions using numerical simulations. The shell-to-shell energy transfers for the turbulent flows are {\\\\em forward and local} for both inertial and dissipative range, but those for the laminar flows are {\\\\em forward and nonlocal}.

OpenCyto: an open source infrastructure for scalable, robust, reproducible, and automated, end-to-end flow cytometry data analysis.

Directory of Open Access Journals (Sweden)

Greg Finak

2014-08-01

Full Text Available Flow cytometry is used increasingly in clinical research for cancer, immunology and vaccines. Technological advances in cytometry instrumentation are increasing the size and dimensionality of data sets, posing a challenge for traditional data management and analysis. Automated analysis methods, despite a general consensus of their importance to the future of the field, have been slow to gain widespread adoption. Here we present OpenCyto, a new BioConductor infrastructure and data analysis framework designed to lower the barrier of entry to automated flow data analysis algorithms by addressing key areas that we believe have held back wider adoption of automated approaches. OpenCyto supports end-to-end data analysis that is robust and reproducible while generating results that are easy to interpret. We have improved the existing, widely used core BioConductor flow cytometry infrastructure by allowing analysis to scale in a memory efficient manner to the large flow data sets that arise in clinical trials, and integrating domain-specific knowledge as part of the pipeline through the hierarchical relationships among cell populations. Pipelines are defined through a text-based csv file, limiting the need to write data-specific code, and are data agnostic to simplify repetitive analysis for core facilities. We demonstrate how to analyze two large cytometry data sets: an intracellular cytokine staining (ICS data set from a published HIV vaccine trial focused on detecting rare, antigen-specific T-cell populations, where we identify a new subset of CD8 T-cells with a vaccine-regimen specific response that could not be identified through manual analysis, and a CyTOF T-cell phenotyping data set where a large staining panel and many cell populations are a challenge for traditional analysis. The substantial improvements to the core BioConductor flow cytometry packages give OpenCyto the potential for wide adoption. It can rapidly leverage new developments in

Impact of top end anastomosis design on patency and flow stability in coronary artery bypass grafting.

Science.gov (United States)

Koyama, Sachi; Kitamura, Tadashi; Itatani, Keiichi; Yamamoto, Tadashi; Miyazaki, Shohei; Oka, Norihiko; Nakashima, Kouki; Horai, Tetsuya; Ono, Minoru; Miyaji, Kagami

2016-05-01

For coronary artery bypass grafting (CABG), free grafts such as a saphenous vein or radial artery are often used for grafts to the lateral and posterior walls. However, the relationship between top-end anastomosis design and long-term patency remains unknown. Because coronary artery blood flow is dominant during diastole, top-end anastomosis may work better if the graft is directed towards the apex, whereas the shortest graft pathway appears to be most efficient. Using computational fluid dynamic models, we evaluated the hemodynamic variables that were affected by the angle of the top-end anastomosis. We created three-dimensional geometries of the aortic root with coronary arteries that involved 75 % stenosis in the obtuse marginal and postero-lateral branches. Two bypass models under vasodilator administration were created: in a"Model A", the top-end anastomosis is parallel to the long axis of the ascending aorta and the graft passed over the conus directed towards the apex; in a "Model B", the top-end anastomosis is directed toward the shortest pathway, and form near the right angles to the long axis of the ascending aorta. Wall shear stress (WSS) and its fluctuation, an oscillatory shear index (OSI) were evaluated to predict fibrosis progression at the anastomosis site and graft flow. Graft flow was 197.3 ml/min and 207.3 ml/min in the "Model A" and "Model B", respectively. The minimal WSS value inside the graft with the "Model A" and "Model B" was 0.53 Pa and 4.09 Pa, respectively, and the OSI value was 0.46 and 0.04, respectively. The top-end anastomosis of a free graft should be directed vertically towards the aorta to achieve the shortest graft pathway to maintain a high graft flow rate and to avoid the risks of endothelial fibrosis and plaque progression over the long-term after CABG.

Size and importance of small electrical end uses in households

Energy Technology Data Exchange (ETDEWEB)

Broderick, J R; Zogg, R A; Alberino, D L

1998-07-01

Miscellaneous end uses (an energy-consumption category in the residential sector) has recently emerged with more importance than ever before. Miscellaneous end uses are a collection of numerous end uses (often unrelated in technology or market characteristics) that individually are small consumers but when grouped together can become notable in size. The Annual Energy Outlook 1998, published by the Energy Information Administration (EIA), suggests that about 32% of residential electricity use in 1996 is attributable to miscellaneous end uses (21% from the Other Uses category and 11% from other miscellaneous categories). The EIA predicts this consumption will grow to about 47% of residential electricity use by 2010. Other studies have shown substantial consumption in this category, and forecast substantial future growth as well. However, it is not clear that the current accounting structure of the miscellaneous category is the most appropriate one, nor that the forecast growth in consumption will materialize. A bottom-up study on a collection of miscellaneous electric end uses was performed to better understand this complex, ill-defined category. Initial results show that many end uses can be categorized more appropriately, such as furnace fans, which belong in Space Heating. A recommended categorization reduces the Other Uses category from 21% to 12% of electric consumption estimated in 1996. Thus, the consumption from miscellaneous end uses is not nearly as large as thought. Furthermore, the growth rate associated with small end uses is projected to be lower relative to projections from other sources.

Analysis of energy flow during playground surface impacts.

Science.gov (United States)

Davidson, Peter L; Wilson, Suzanne J; Chalmers, David J; Wilson, Barry D; Eager, David; McIntosh, Andrew S

2013-10-01

The amount of energy dissipated away from or returned to a child falling onto a surface will influence fracture risk but is not considered in current standards for playground impact-attenuating surfaces. A two-mass rheological computer simulation was used to model energy flow within the wrist and surface during hand impact with playground surfaces, and the potential of this approach to provide insights into such impacts and predict injury risk examined. Acceleration data collected on-site from typical playground surfaces and previously obtained data from children performing an exercise involving freefalling with a fully extended arm provided input. The model identified differences in energy flow properties between playground surfaces and two potentially harmful surface characteristics: more energy was absorbed by (work done on) the wrist during both impact and rebound on rubber surfaces than on bark, and rubber surfaces started to rebound (return energy to the wrist) while the upper limb was still moving downward. Energy flow analysis thus provides information on playground surface characteristics and the impact process, and has the potential to identify fracture risks, inform the development of safer impact-attenuating surfaces, and contribute to development of new energy-based arm fracture injury criteria and tests for use in conjunction with current methods.

High-energy redox-flow batteries with hybrid metal foam electrodes.

Science.gov (United States)

Park, Min-Sik; Lee, Nam-Jin; Lee, Seung-Wook; Kim, Ki Jae; Oh, Duk-Jin; Kim, Young-Jun

2014-07-09

A nonaqueous redox-flow battery employing [Co(bpy)3](+/2+) and [Fe(bpy)3](2+/3+) redox couples is proposed for use in large-scale energy-storage applications. We successfully demonstrate a redox-flow battery with a practical operating voltage of over 2.1 V and an energy efficiency of 85% through a rational cell design. By utilizing carbon-coated Ni-FeCrAl and Cu metal foam electrodes, the electrochemical reactivity and stability of the nonaqueous redox-flow battery can be considerably enhanced. Our approach intoduces a more efficient conversion of chemical energy into electrical energy and enhances long-term cell durability. The cell exhibits an outstanding cyclic performance of more than 300 cycles without any significant loss of energy efficiency. Considering the increasing demands for efficient energy storage, our achievement provides insight into a possible development pathway for nonaqueous redox-flow batteries with high energy densities.

Basic study on an energy conversion system using boiling two-phase flows of temperature-sensitive magnetic fluid. Theoretical analysis based on thermal nonequilibrium model and flow visualization using ultrasonic echo

International Nuclear Information System (INIS)

Ishimoto, Jun; Kamiyama, Shinichi; Okubo, Masaaki.

1995-01-01

Effects of magnetic field on the characteristics of boiling two-phase pipe flow of temperature-sensitive magnetic fluid are clarified in detail both theoretically and experimentally. Firstly, governing equations of two-phase magnetic fluid flow based on the thermal nonequilibrium two-fluid model are presented and numerically solved considering evaporation and condensation between gas- and liquid-phases. Next, behaviour of vapor bubbles is visualized with ultrasonic echo in the region of nonuniform magnetic field. This is recorded and processed with an image processor. As a result, the distributions of void fraction in the two-phase flow are obtained. Furthermore, detailed characteristics of the two-phase magnetic fluid flow are investigated using a small test loop of the new energy conversion system. From the numerical and experimental results, it is known that the precise control of the boiling two-phase flow and bubble generation is possible by using the nonuniform magnetic field effectively. These fundamental studies on the characteristics of two-phase magnetic fluid flow will contribute to the development of the new energy conversion system using a gas-liquid boiling two-phase flow of magnetic fluid. (author)

Transverse and radial flow in intermediate energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Vestfall, D. Gary

1997-01-01

We have studied transverse and radial flow in nucleus-nucleus collisions ranging in energy from 15 to 155 MeV/nucleon. We have measured the impact parameter dependence of the balance energy for Ar + Sc and compared the results with Quantum Molecular Dynamics calculations with and without momentum dependence. We have shown that transverse flow and the balance energy dependence on the isospin of the system using the systems 58 Fe + 58 Fe, 58 Ni + 58 Ni, and 58 Mn + 58 Fe. These results are compared with Boltzmann-Uehling-Uehlenbeck calculations incorporating isospin-dependence. We have measured radial flow for Ar + Sc and find that about 50% of the observed energy is related to radial flow. (author)

Design, Analysis, and Evaluation of a Compact Electromagnetic Energy Harvester from Water Flow for Remote Sensors

Directory of Open Access Journals (Sweden)

Tao Wang

2018-06-01

Full Text Available This paper develops an electromagnetic energy harvester, which can generate small-scale electricity from non-directional water flow in oceans or rivers for remote sensors. The energy harvester integrates a Tesla disk turbine, a miniature axial-flux permanent magnet generator, and a ring cover with symmetrical grooves which are utilized to rectify flow direction. A compact structure is achieved by mounting the permanent magnets of the generator directly on the end surfaces of the turbine rotor. Theoretical analysis is implemented to illustrate the energy conversion process between flow kinetic form and electrical form. Additionally, a mathematical model is developed to investigate the magnetic field distribution produced by the cubical permanent magnets as well as parametric effect. Plastic prototypes with a diameter of 65 mm and a height of 46 mm are fabricated by using a 3D printing technique. The effect of the groove angle is experimentally investigated and compared under a no-load condition. The prototype with the optimal groove angle can operate at flow velocity down to 0.61 m/s and can induce peak-to-peak electromotive force of 2.64–11.92 V at flow velocity of 0.61–1.87 m/s. It can be observed from the results that the analytical and the measured curves are in good accordance. Loaded experiments show that the output electrical power is 23.1 mW at flow velocity of 1.87 m/s when the load resistance is approximately equal to the coil resistance. The advantages and disadvantages of the proposed energy harvester are presented through comparison with existing similar devices.

Energy flow in photonic crystal waveguides

DEFF Research Database (Denmark)

Søndergaard, Thomas; Dridi, Kim

2000-01-01

Theoretical and numerical investigations of energy flow in photonic crystal waveguides made of line defects and branching points are presented. It is shown that vortices of energy flow may occur, and the net energy flow along: the line defect is described via the effective propagation velocity....... Single-mode and multimode operations are studied, and dispersion relations are computed for different waveguide widths. Both strong positive, strong negative, and zero dispersion an possible. It is shown that geometric parameters such as the nature of the lattice, the line defect orientation, the defect...... width, and the branching-point geometry have a significant influence on the electrodynamics. These are important issues for the fabrication of photonic crystal structures....

Resource efficiency of urban sanitation systems. A comparative assessment using material and energy flow analysis

Energy Technology Data Exchange (ETDEWEB)

Meinzinger, Franziska

2010-07-01

Within the framework of sustainable development it is important to find ways of reducing natural resource consumption and to change towards closed-loop management. As in many other spheres increased resource efficiency has also become an important issue in sanitation. Particularly nutrient recovery for agriculture, increased energy-efficiency and saving of natural water resources, can make a contribution to more resource efficient sanitation systems. To assess the resource efficiency of alternative developments a systems perspective is required. The present study applies a combined cost, energy and material flow analysis (ceMFA) as a system analysis method to assess the resource efficiency of urban sanitation systems. This includes the discussion of relevant criteria and assessment methods. The main focus of this thesis is the comparative assessment of different systems, based on two case studies; Hamburg in Germany and Arba Minch in Ethiopia. A range of possible system developments including source separation (e.g. diversion of urine or blackwater) is defined and compared with the current situation as a reference system. The assessment is carried out using computer simulations based on model equations. The model equations not only integrate mass and nutrient flows, but also the energy and cost balances of the different systems. In order to assess the impact of different assumptions and calculation parameters, sensitivity analyses and parameter variations complete the calculations. Based on the simulations, following general conclusions can be drawn: None of the systems show an overall benefit with regard to all investigated criteria, namely nutrients, energy, water and costs. Yet, the results of the system analysis can be used as basis for decision making if a case-related weighting is introduced. The systems show varying potential for the recovery of nutrients from (source separated) wastewater flows. For the case study of Hamburg up to 29% of the mineral

Front-end electronics for accurate energy measurement of double beta decays

International Nuclear Information System (INIS)

Gil, A.; Díaz, J.; Gómez-Cadenas, J.J.; Herrero, V.; Rodriguez, J.; Serra, L.; Toledo, J.; Esteve, R.; Monzó, J.M.; Monrabal, F.; Yahlali, N.

2012-01-01

NEXT, a double beta decay experiment that will operate in Canfranc Underground Laboratory (Spain), aims at measuring the neutrinoless double-β decay of the 136Xe isotope using a TPC filled with enriched Xenon gas at high pressure operated in electroluminescence mode. One technological challenge of the experiment is to achieve resolution better than 1% in the energy measurement using a plane of UV sensitive photomultipliers readout with appropriate custom-made front-end electronics. The front-end is designed to be sensitive to the single photo-electron to detect the weak primary scintillation light produced in the chamber, and also to be able to cope with the electroluminescence signal (several hundred times higher and with a duration of microseconds). For efficient primary scintillation detection and precise energy measurement of the electroluminescent signals the front-end electronics features low noise and adequate amplification. The signal shaping provided allows the digitization of the signals at a frequency as low as 40 MHz.

Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage

Energy Technology Data Exchange (ETDEWEB)

None

2010-10-01

GRIDS Project: LBNL is designing a flow battery for grid storage that relies on a hydrogen-bromine chemistry which could be more efficient, last longer and cost less than today’s lead-acid batteries. Flow batteries are fundamentally different from traditional lead-acid batteries because the chemical reactants that provide their energy are stored in external tanks instead of inside the battery. A flow battery can provide more energy because all that is required to increase its storage capacity is to increase the size of the external tanks. The hydrogen-bromine reactants used by LBNL in its flow battery are inexpensive, long lasting, and provide power quickly. The cost of the design could be well below $100 per kilowatt hour, which would rival conventional grid-scale battery technologies.

Analysis of changing hidden energy flow in Vietnam

International Nuclear Information System (INIS)

Nguyen Thi Anh Tuyet; Ishihara, Keiichi N.

2006-01-01

The energy consumption in production process is changing especially in developing countries by substituting technology. Input-output analysis for energy flows has been developing and is one of the best solutions for investigating macroscopic exchanges of both economy and energy. Since each element in the Leontief inverse contains both direct and indirect effects of any change in final demand, to separate those direct and indirect effects, the power series expansion is available. In this work, the changes of embodied energy intensity in Vietnam from 1996 to 2000 were analyzed using the structural decomposition and its power series expansion. By illustrating the change of causal relationship between direct energy consumption and embodied energy consumption, the change of hidden energy flow, which indicates how the changing embodied energy builds up the change of direct energy consumption in every sector, can be seen. In the case study, the rice processing sector, which is one of the important food processing sectors in Vietnam, is focused. By drawing a diagrammatic map for the change of hidden energy flow, it is clarified that in the case of raising embodied energy intensity, cultivation sector and trade and repaired service sector are the main contributors, and, on the contrary, in the case of reducing embodied energy intensity, paper pulp sector is the main contributor

Using Flow Electrodes in Multiple Reactors in Series for Continuous Energy Generation from Capacitive Mixing

KAUST Repository

Hatzell, Marta C.

2014-12-09

Efficient conversion of “mixing energy” to electricity through capacitive mixing (CapMix) has been limited by low energy recoveries, low power densities, and noncontinuous energy production resulting from intermittent charging and discharging cycles. We show here that a CapMix system based on a four-reactor process with flow electrodes can generate constant and continuous energy, providing a more flexible platform for harvesting mixing energy. The power densities were dependent on the flow-electrode carbon loading, with 5.8 ± 0.2 mW m–2 continuously produced in the charging reactor and 3.3 ± 0.4 mW m–2 produced in the discharging reactor (9.2 ± 0.6 mW m–2 for the whole system) when the flow-electrode carbon loading was 15%. Additionally, when the flow-electrode electrolyte ion concentration increased from 10 to 20 g L–1, the total power density of the whole system (charging and discharging) increased to 50.9 ± 2.5 mW m–2.

Social acceptance of solar energy technologies in China-End users' perspective

International Nuclear Information System (INIS)

Yuan Xueliang; Zuo Jian; Ma Chunyuan

2011-01-01

Energy is essential to human beings. The increasing demand of energy has triggered the public scrutiny on the sustainability issues associated with the energy production and transmission. There have been a large number of studies focusing on reducing the environmental impacts associated with the energy sector. Renewable energy sources such as solar energy have been prompted to mitigate these environmental impacts. This research adopted a quantitative approach to investigate the social acceptance of solar energy technologies from end users' perspective in Shandong province, China. A large scale questionnaire survey was conducted. The results show that there is a considerable high level of social acceptance and public awareness of solar water heater. However, another major application of solar energy, solar PV has not gained a high level of social acceptance or public awareness in Shandong. This study provides useful references for policy makers to further promote the utilization of solar energy innovations. - Research Highlights: → Social acceptance of solar energy technologies from end users' perspective is investigated by a large scale questionnaire survey. → Higher level of social acceptance and public awareness of solar water heater than solar PV. → Impact factors for social acceptance of solar energy technologies are analyzed.

Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

Science.gov (United States)

Hoffmann, D.; Willmann, A.; Göpfert, R.; Becker, P.; Folkmer, B.; Manoli, Y.

2013-12-01

In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced.

Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

International Nuclear Information System (INIS)

Hoffmann, D; Willmann, A; Göpfert, R; Becker, P; Folkmer, B; Manoli, Y

2013-01-01

In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced

Free Energy, Enthalpy and Entropy from Implicit Solvent End-Point Simulations.

Science.gov (United States)

Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro

2018-01-01

Free energy is the key quantity to describe the thermodynamics of biological systems. In this perspective we consider the calculation of free energy, enthalpy and entropy from end-point molecular dynamics simulations. Since the enthalpy may be calculated as the ensemble average over equilibrated simulation snapshots the difficulties related to free energy calculation are ultimately related to the calculation of the entropy of the system and in particular of the solvent entropy. In the last two decades implicit solvent models have been used to circumvent the problem and to take into account solvent entropy implicitly in the solvation terms. More recently outstanding advancement in both implicit solvent models and in entropy calculations are making the goal of free energy estimation from end-point simulations more feasible than ever before. We review briefly the basic theory and discuss the advancements in light of practical applications.

Free Energy, Enthalpy and Entropy from Implicit Solvent End-Point Simulations

Directory of Open Access Journals (Sweden)

Federico Fogolari

2018-02-01

Full Text Available Free energy is the key quantity to describe the thermodynamics of biological systems. In this perspective we consider the calculation of free energy, enthalpy and entropy from end-point molecular dynamics simulations. Since the enthalpy may be calculated as the ensemble average over equilibrated simulation snapshots the difficulties related to free energy calculation are ultimately related to the calculation of the entropy of the system and in particular of the solvent entropy. In the last two decades implicit solvent models have been used to circumvent the problem and to take into account solvent entropy implicitly in the solvation terms. More recently outstanding advancement in both implicit solvent models and in entropy calculations are making the goal of free energy estimation from end-point simulations more feasible than ever before. We review briefly the basic theory and discuss the advancements in light of practical applications.

Emulsification kinetics during quasi-miscible flow in dead-end pores

Science.gov (United States)

Broens, M.; Unsal, E.

2018-03-01

Microemulsions have found applications as carriers for the transport of solutes through various porous media. They are commonly pre-prepared in bulk form, and then injected into the medium. The preparation is done by actively mixing the surfactant, water and oil, and then allowing the mixture to stagnate until equilibrium is reached. The resulting microemulsion characteristics of the surfactant/oil/water system are studied at equilibrium conditions, and perfect mixing is assumed. But in applications like subsurface remediation and enhanced oil recovery, microemulsion formation may occur in the pore space. Surfactant solutions are injected into the ground to solubilize and/or mobilize the non-aqueous phase liquids (NAPLs) by in-situ emulsification. Flow dynamics and emulsification kinetics are coupled, which also contributes to in-situ mixing. In this study, we investigated the nature of such coupling for a quasi-miscible fluid system in a conductive channel with dead-end extensions. A microfluidic setup was used, where an aqueous solution of an anionic, internal olefin sulfonate 20-24 (IOS) surfactant was injected into n-decane saturated glass micromodel. The oil phase was coloured using a solvatochromatic dye allowing for direct visualization of the aqueous and oil phases as well as their microemulsions under fluorescent light. Presence of both conductive and stagnant dead-end channels in a single pore system made it possible to isolate different transport mechanisms from each other but also allowed to study the transitions from one to the other. In the conductive channel, the surfactant was carried with flow, and emulsification was controlled by the localized flow dynamics. In the stagnant zones, the driving force of the mass transfer was driven by the chemical concentration gradient. Some of the equilibrium phase behaviour characteristics of the surfactant/oil/water system were recognisable during the quasi-miscible displacement. However, the equilibrium tests

Sleep Management on Multiple Machines for Energy and Flow Time

DEFF Research Database (Denmark)

Chan, Sze-Hang; Lam, Tak-Wah; Lee, Lap Kei

2011-01-01

In large data centers, determining the right number of operating machines is often non-trivial, especially when the workload is unpredictable. Using too many machines would waste energy, while using too few would affect the performance. This paper extends the traditional study of online flow-time...... scheduling on multiple machines to take sleep management and energy into consideration. Specifically, we study online algorithms that can determine dynamically when and which subset of machines should wake up (or sleep), and how jobs are dispatched and scheduled. We consider schedules whose objective...... is to minimize the sum of flow time and energy, and obtain O(1)-competitive algorithms for two settings: one assumes machines running at a fixed speed, and the other allows dynamic speed scaling to further optimize energy usage. Like the previous work on the tradeoff between flow time and energy, the analysis...

Electromagnetic energy flow lines as possible paths of photons

Energy Technology Data Exchange (ETDEWEB)

Davidovic, M [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, 11000 Belgrade (Serbia); Sanz, A S; Miret-Artes, S [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones CientIficas, Serrano 123, 28006 Madrid (Spain); Arsenovic, D; Bozic, M [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia)], E-mail: milena@grf.bg.ac.yu, E-mail: asanz@imaff.cfmac.csic.es, E-mail: arsenovic@phy.bg.ac.yu, E-mail: bozic@phy.bg.ac.yu, E-mail: s.miret@imaff.cfmac.csic.es

2009-07-15

Motivated by recent experiments where interference patterns behind a grating are obtained by accumulating single photon events, we provide here an electromagnetic energy flow-line description to explain the emergence of such patterns. We find and discuss an analogy between the equation describing these energy flow lines and the equation of Bohmian trajectories used to describe the motion of massive particles.

Flow and wall shear stress in end-to-side and side-to-side anastomosis of venous coronary artery bypass grafts

Directory of Open Access Journals (Sweden)

Poulikakos Dimos

2007-09-01

Full Text Available Abstract Purpose Coronary artery bypass graft (CABG surgery represents the standard treatment of advanced coronary artery disease. Two major types of anastomosis exist to connect the graft to the coronary artery, i.e., by using an end-to-side or a side-to-side anastomosis. There is still controversy because of the differences in the patency rates of the two types of anastomosis. The purpose of this paper is to non-invasively quantify hemodynamic parameters, such as mass flow and wall shear stress (WSS, in end-to-side and side-to-side anastomoses of patients with CABG using computational fluid dynamics (CFD. Methods One patient with saphenous CABG and end-to-side anastomosis and one patient with saphenous CABG and side-to-side anastomosis underwent 16-detector row computed tomography (CT. Geometric models of coronary arteries and bypasses were reconstructed for CFD analysis. Blood flow was considered pulsatile, laminar, incompressible and Newtonian. Peri-anastomotic mass flow and WSS were quantified and flow patterns visualized. Results CFD analysis based on in-vivo CT coronary angiography data was feasible in both patients. For both types of CABG, flow patterns were characterized by a retrograde flow into the native coronary artery. WSS variations were found in both anastomoses types, with highest WSS values at the heel and lowest WSS values at the floor of the end-to-side anastomosis. In contrast, the highest WSS values of the side-to-side anastomosis configuration were found in stenotic vessel segments and not in the close vicinity of the anastomosis. Flow stagnation zones were found in end-to-side but not in side-to-side anastomosis, the latter also demonstrating a smoother stream division throughout the cardiac cycle. Conclusion CFD analysis of venous CABG based on in-vivo CT datasets in patients was feasible producing qualitative and quantitative information on mass flow and WSS. Differences were found between the two types of anastomosis

Beam Flutter and Energy Harvesting in Internal Flow

Science.gov (United States)

Tosi, Luis Phillipe; Colonius, Tim; Sherrit, Stewart; Lee, Hyeong Jae

2017-11-01

Aeroelastic flutter, largely studied for causing engineering failures, has more recently been used as a means of extracting energy from the flow. Particularly, flutter of a cantilever or an elastically mounted plate in a converging-diverging flow passage has shown promise as an energy harvesting concept for internal flow applications. The instability onset is observed as a function of throat velocity, internal wall geometry, fluid and structure material properties. To enable these devices, our work explores features of the fluid-structure coupled dynamics as a function of relevant nondimensional parameters. The flutter boundary is examined through stability analysis of a reduced order model, and corroborated with numerical simulations at low Reynolds number. Experiments for an energy harvester design are qualitatively compared to results from analytical and numerical work, suggesting a robust limit cycle ensues due to a subcritical Hopf bifurcation. Bosch Corporation.

Energy flow models for the estimation of technical losses in distribution network

International Nuclear Information System (INIS)

Au, Mau Teng; Tan, Chin Hooi

2013-01-01

This paper presents energy flow models developed to estimate technical losses in distribution network. Energy flow models applied in this paper is based on input energy and peak demand of distribution network, feeder length and peak demand, transformer loading capacity, and load factor. Two case studies, an urban distribution network and a rural distribution network are used to illustrate application of the energy flow models. Results on technical losses obtained for the two distribution networks are consistent and comparable to network of similar types and characteristics. Hence, the energy flow models are suitable for practical application.

Influences of viscous losses and end effects on liquid metal flow in electromagnetic pumps

International Nuclear Information System (INIS)

Kim, Hee Reyoung; Seo, Joon Ho; Hong, Sang Hee; Cho, Su won; Nam, Ho Yun; Cho, Man

1996-01-01

Analyses of the viscous and end effects on electromagnetic (EM) pumps of annular linear induction type for the sodium coolant circulation in Liquid Metal Fast Breeder Reactors have been carried out based on the MHD laminar flow analysis and the electromagnetic field theory. A one-dimensional MHD analysis for the liquid metal flowing through an annular channel has been performed on the basis of a simplified model of equivalent current sheets instead of three-phase currents in the discrete primary windings. The calculations show that the developed pressure difference resulted from electromagnetic and viscous forces in the liquid metal is expressed in terms of the slip, and that the viscous loss effects are negligible compared with electromagnetic driving forces except in the low-slip region where the pumps operate with very high flow velocities comparable with the synchronous velocity of the electromagnetic fields, which is not applicable to the practical EM pumps. A two-dimensional electromagnetic field analysis based on an equivalent current sheet model has found the vector potentials in closed form by means of the Fourier transform method. The resultant magnetic fields and driving forces exerted on the liquid metal reveal that the end effects due to finiteness of the pump length are formidable. In addition, a two-dimensional numerical analysis for vector potentials has been performed by the SOR iterative method on a realistic EM pump model with discretely-distributed currents in the primary windings. The numerical computations for the distributions of magnetic fields and developed pressure differences along the pump axial length also show considerable end effects at both inlet and outlet ends, especially at high flow velocities. Calculations of each magnetic force contribution indicate that the end effects are originated from the magnetic force caused by the induced current (υxB) generated by the liquid metal movement across the magnetic field rather than the one

VME as a front-end electronics system in high energy physics experiments

International Nuclear Information System (INIS)

Ohska, T.K.

1990-01-01

It is only a few years since the VME became a standard system, yet the VME system is already so much more popular than other systems. The VME system was developed for industrial applications and not for the scientific research, and high energy physics field is a tiny market when compared with the industrial market. Considerations made here indicate that the VME system would be a good one for a rear-end system, but would not be a good candidate for front-end electronics in physics experiments. Furthermore, there is a fear that the VXI bus could become popular in this field of instrumentation since the VXI system is backed up by major suppliers of instrumentation in the high energy physics field. VXI would not be an adequate system for front-end electronics, yet advertised to be one. It would be worse to see the VXI system to become a standard system for high energy physics instrumentation than the VME system to be one. The VXI system would do a mediocre job so that people might be misled to think that the VXI system can be used as front-end system. (N.K.)

Stability of boundary layer flow based on energy gradient theory

Science.gov (United States)

Dou, Hua-Shu; Xu, Wenqian; Khoo, Boo Cheong

2018-05-01

The flow of the laminar boundary layer on a flat plate is studied with the simulation of Navier-Stokes equations. The mechanisms of flow instability at external edge of the boundary layer and near the wall are analyzed using the energy gradient theory. The simulation results show that there is an overshoot on the velocity profile at the external edge of the boundary layer. At this overshoot, the energy gradient function is very large which results in instability according to the energy gradient theory. It is found that the transverse gradient of the total mechanical energy is responsible for the instability at the external edge of the boundary layer, which induces the entrainment of external flow into the boundary layer. Within the boundary layer, there is a maximum of the energy gradient function near the wall, which leads to intensive flow instability near the wall and contributes to the generation of turbulence.

Control of open end plasma flow utilizing orbital stochasticity

International Nuclear Information System (INIS)

Hojo, Hitoshi

1995-01-01

It has been known that the control of plasma outside the confinement region of diverter plasma and others in a magnetic field confinement device is very important for improveing the confinement of bulk plasma. The control of plasma outside a confinement region bears two roles, one is the reduction of the thermal load on a diverter plate and others due to the plasma particles lost from the confinement region, and another is the restriction of the back flow of cold plasma and impurities generated outside the confinement region to a bulk plasma region. In this study, the new method of controlling plasma outside a confinement region called magnetic diverter is considered. To the plasma particles advancing along magnetic force lines, the reflection and capture of the plasma particles occur in the region of orbital stochasticity, and the thermal load on an end plate and the reverse flow to a bulk plasma region are restricted. The numerical computation model used regarding the particle control utilizing the orbital stochasticity and the results of calculating the orbit of plasma particles in a magnetic field are reported. (K.I.)

A mean flow acoustic engine capable of wind energy harvesting

International Nuclear Information System (INIS)

Sun Daming; Xu Ya; Chen Haijun; Wu, Ke; Liu Kaikai; Yu Yan

2012-01-01

Highlights: ► A mean flow acoustic engine for wind energy harvesting is designed and manufactured. ► Stable standing wave acoustic field is established at specific flow velocity. ► Experimental and computational results reveal the acoustic field characteristics. ► Acoustic field has monofrequency characteristic and remarkable energy density. - Abstract: Based on the mean flow induced acoustic oscillation effect, a mean flow acoustic engine (MFAE) converts wind energy and fluid energy in pipeline into acoustic energy which can be used to drive thermoacoustic refrigerators and generators without any mechanical moving parts. With natural wind simulated by a centrifugal air fan, a MFAE with a cross-junction configuration was designed and manufactured for experimental study. Stable standing wave acoustic fields were established in specific ranges of air flow velocity. Experimental and computational results reveal the acoustic field distribution in the engine and show the effect of the mean flow velocity and the Strouhal number on the acoustic field characteristics. With a mean flow velocity of 50.52 m/s and a mean pressure of 106.19 kPa, the maximum pressure amplitude of 6.20 kPa was achieved, which was about 5.8% of the mean pressure. It has laid a good foundation for driving power generation devices and thermoacoustic refrigerators by a MFAE.

Generalized Energy Flow Analysis Considering Electricity Gas and Heat Subsystems in Local-Area Energy Systems Integration

Directory of Open Access Journals (Sweden)

Jiaqi Shi

2017-04-01

Full Text Available To alleviate environmental pollution and improve the efficient use of energy, energy systems integration (ESI—covering electric power systems, heat systems and natural gas systems—has become an important trend in energy utilization. The traditional power flow calculation method, with the object as the power system, will prove difficult in meeting the requirements of the coupled energy flow analysis. This paper proposes a generalized energy flow (GEF analysis method which is suitable for an ESI containing electricity, heat and gas subsystems. First, the models of electricity, heat, and natural gas networks in the ESI are established. In view of the complexity of the conventional method to solve the gas network including the compressor, an improved practical equivalent method was adopted based on different control modes. On this basis, a hybrid method combining homotopy and the Newton-Raphson algorithm was executed to compute the nonlinear equations of GEF, and the Jacobi matrix reflecting the coupling relationship of multi-energy was derived considering the grid connected mode and island modes of the power system in the ESI. Finally, the validity of the proposed method in multi-energy flow calculation and the analysis of interacting characteristics was verified using practical cases.

INDRA-GSI: Collective flow from Fermi to relativistic energies

Energy Technology Data Exchange (ETDEWEB)

Lukasik, J.; Trautmann, W.; Begemann-Blaich, M.L.; Bittiger, R.; Gourio, D.; Le Fevre, A.; Lynen, U.; Mueller, W.F.J.; Orth, H.; Sfienti, C.; Schwarz, C.; Turzo, K. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Auger, G.; Bouriquet, B.; Chbihi, A.; Frankland, J.D.; Hudan, S.; Lopez, O. [GANIL, CEA et IN2P3-CNRS, 14 - Caen (France); Borderie, B.; Galichet, E.; Lavaud, F.; Plagnol, E. [Paris-11 Univ., Institut de Physique Nucleaire, IN2P3-CNRS, 91 - Orsay (France); Bellaize, N.; Bocage, F.; Bougault, R.; Durand, D.; Hurst, B.; Steckmeyer, J.C.; Tamain, B.; Vient, E. [Caen Univ., LPC (IN2P3-CNRS/ENSI), 14 - Caen (France); Charvet, J.L.; Dayras, R.; Legrain, R.; Nalpas, L.; Volant, C. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee (DAPNIA/SPhN), 91- Gif sur Yvette (France); Guinet, D.; Lautesse, P. [Institut de Physique Nucleaire, IN2P3-CNRS et Universite, 69 - Villeurbanne (France); Rosato, E.; Vigilante, M. [INFN, Univ. Federico II, Dipartimento di Scienze Fisiche e Sezione, Napoli (Italy); Saija, A. [Universita and INFN I, Dipartimento di Fisica dell' , Catania (Italy); Trzcinski, A.; Zwieglinski, B. [A. Soltan Institute for Nuclear Studies, Warsaw (Poland); Lukasik, J. [H. Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Galichet, E. [Conservatoire National des Arts et Metiers, 75 - Paris (France)

2003-07-01

Directed flow for the {sup 197}Au + {sup 197}Au reactions at incident energies between 40 and 150 A*MeV has been measured using the 4{pi} multi-detector INDRA at the GSI facility. In particular, the bombarding energy at which the elliptic flow switches from in-plane to out-of-plane enhancement has been determined to be around 100 A*MeV in good agreement with the result obtained by the FOPI Collaboration. The new data allows also to extend the experimental excitation function of v{sub 2} to lower energies. (authors)

INDRA-GSI: Collective flow from Fermi to relativistic energies

International Nuclear Information System (INIS)

Lukasik, J.; Trautmann, W.; Begemann-Blaich, M.L.; Bittiger, R.; Gourio, D.; Le Fevre, A.; Lynen, U.; Mueller, W.F.J.; Orth, H.; Sfienti, C.; Schwarz, C.; Turzo, K.; Auger, G.; Bouriquet, B.; Chbihi, A.; Frankland, J.D.; Hudan, S.; Lopez, O.; Borderie, B.; Galichet, E.; Lavaud, F.; Plagnol, E.; Bellaize, N.; Bocage, F.; Bougault, R.; Durand, D.; Hurst, B.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Charvet, J.L.; Dayras, R.; Legrain, R.; Nalpas, L.; Volant, C.; Guinet, D.; Lautesse, P.; Rosato, E.; Vigilante, M.; Saija, A.; Trzcinski, A.; Zwieglinski, B.; Lukasik, J.; Galichet, E.

2003-01-01

Directed flow for the 197 Au + 197 Au reactions at incident energies between 40 and 150 A*MeV has been measured using the 4π multi-detector INDRA at the GSI facility. In particular, the bombarding energy at which the elliptic flow switches from in-plane to out-of-plane enhancement has been determined to be around 100 A*MeV in good agreement with the result obtained by the FOPI Collaboration. The new data allows also to extend the experimental excitation function of v 2 to lower energies. (authors)

Energy use, energy use in mainland Norway; Energibruk, energibruk i Fastlands-Noreg

Energy Technology Data Exchange (ETDEWEB)

Magnussen, Ingrid H.; Spilde, Dag; Killingland, Magnus

2011-05-15

The purpose of this report is to describe the development of energy in the mainland, with emphasis on key developments within the major end user groups. At the same time we explain concepts and relationships that are often used within the field of energy. Finally, we look at forecasts for future energy use that is made by environments outside NVE. The total end use of energy in the mainland was 207 TWh in 2009. The most important end user groups are households, service industries, manufacturing and transportation industries. Additionally, it was used 15 TWh in the energy sector in the mainland. Energy used in the energy sector will not be considered as end use since it's going to produce new energy products. The long-term trend of energy consumption in the mainland is that fuel for transport and electricity for energy sector is increasing, while energy consumption in other sectors flattens out. The reason for increase of fuel for transport is the increasing number of motorized equipment and vehicles in mainland Norway, which has led to the consumption of petrol and diesel have risen by 75 percent since 1976. The petroleum sector is the largest user of energy in the energy sector in Mainland, and electricity from land to the platforms in the North Sea and new facilities on land has led to electricity usage has increased from 1 TWh in 1995 to 5 TWh in 2009. Energy consumption in households had a flat trend from 1996 to 2009, after many years of growth. The rationale behind the flattening is partly warmer climate, higher energy prices, heat pumps and more energy-efficient buildings. In service industries, growth in energy consumption decreased since the end of the 1990s, and the explanation of this is much the same as for households. In industry is the closure of energy-intensive businesses and new more energy-efficient enterprises the most important reason that energy use is leveling out. Electricity is the most widely used energy source in Norway, and

CaFE: a tool for binding affinity prediction using end-point free energy methods.

Science.gov (United States)

Liu, Hui; Hou, Tingjun

2016-07-15

Accurate prediction of binding free energy is of particular importance to computational biology and structure-based drug design. Among those methods for binding affinity predictions, the end-point approaches, such as MM/PBSA and LIE, have been widely used because they can achieve a good balance between prediction accuracy and computational cost. Here we present an easy-to-use pipeline tool named Calculation of Free Energy (CaFE) to conduct MM/PBSA and LIE calculations. Powered by the VMD and NAMD programs, CaFE is able to handle numerous static coordinate and molecular dynamics trajectory file formats generated by different molecular simulation packages and supports various force field parameters. CaFE source code and documentation are freely available under the GNU General Public License via GitHub at https://github.com/huiliucode/cafe_plugin It is a VMD plugin written in Tcl and the usage is platform-independent. tingjunhou@zju.edu.cn. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Natural convection heat transfer between vertical channel with flow resistance at the lower end

International Nuclear Information System (INIS)

Iwamoto, S.; Nishimura, S.; Ishihara, I.

2003-01-01

For natural convection in the geometrically complicated channel, the convection flow is suppressed by flow resistance due to such channel itself and the lopsided flow may take place. This could result in serious influences on the heat transfer in the channel. In order to investigate fundamentally the natural convection flow and heat transfer in such the channel, the vertical channel in which wall was heated with uniform heat flux and the flow resistance was given by small clearance between the lower end of channel and a wide horizontal floor. Flow pattern was observed by illuminating smoke filled in the channel and heat transfer rate was measured. (author)

How to engage end-users in smart energy behaviour?

Directory of Open Access Journals (Sweden)

Valkering Pieter

2014-01-01

Full Text Available End users will play a crucial role in up-coming smart grids that aim to link end-users and energy providers in a better balanced and more efficient electricity system. Within this context, this paper aims to deliver a coherent view on current good practice in end-user engagement in smart grid projects. It draws from a recent review of theoretical insights from sustainable consumption behaviour, social marketing and innovation systems and empirical insights from recent smart grid projects to create an inventory of common motivators, enablers and barriers of behavioural change, and the end-user engagement principles that can be derived from that. We conclude with identifying current research challenges as input for a research agenda on end-user engagement in smart grids.

Flow dynamics and energy efficiency of flow in the left ventricle during myocardial infarction.

Science.gov (United States)

Vasudevan, Vivek; Low, Adriel Jia Jun; Annamalai, Sarayu Parimal; Sampath, Smita; Poh, Kian Keong; Totman, Teresa; Mazlan, Muhammad; Croft, Grace; Richards, A Mark; de Kleijn, Dominique P V; Chin, Chih-Liang; Yap, Choon Hwai

2017-10-01

Cardiovascular disease is a leading cause of death worldwide, where myocardial infarction (MI) is a major category. After infarction, the heart has difficulty providing sufficient energy for circulation, and thus, understanding the heart's energy efficiency is important. We induced MI in a porcine animal model via circumflex ligation and acquired multiple-slice cine magnetic resonance (MR) images in a longitudinal manner-before infarction, and 1 week (acute) and 4 weeks (chronic) after infarction. Computational fluid dynamic simulations were performed based on MR images to obtain detailed fluid dynamics and energy dynamics of the left ventricles. Results showed that energy efficiency flow through the heart decreased at the acute time point. Since the heart was observed to experience changes in heart rate, stroke volume and chamber size over the two post-infarction time points, simulations were performed to test the effect of each of the three parameters. Increasing heart rate and stroke volume were found to significantly decrease flow energy efficiency, but the effect of chamber size was inconsistent. Strong complex interplay was observed between the three parameters, necessitating the use of non-dimensional parameterization to characterize flow energy efficiency. The ratio of Reynolds to Strouhal number, which is a form of Womersley number, was found to be the most effective non-dimensional parameter to represent energy efficiency of flow in the heart. We believe that this non-dimensional number can be computed for clinical cases via ultrasound and hypothesize that it can serve as a biomarker for clinical evaluations.

Linking material and energy flow analyses and social theory

Energy Technology Data Exchange (ETDEWEB)

Schiller, Frank [The Open University, Faculty of Maths, Computing and Technology, Walton Hall, Milton Keynes, MK7 6AA (United Kingdom)

2009-04-15

The paper explores the potential of Habermas' theory of communicative action to alter the social reflexivity of material and energy flow analysis. With his social macro theory Habermas has provided an alternative, critical justification for social theory that can be distinguished from economic libertarianism and from political liberalism. Implicitly, most flow approaches draw from these theoretical traditions rather than from discourse theory. There are several types of material and energy flow analyses. While these concepts basically share a system theoretical view, they lack a specific interdisciplinary perspective that ties the fundamental insight of flows to disciplinary scientific development. Instead of simply expanding micro-models to the social macro-dimension social theory suggests infusing the very notion of flows to the progress of disciplines. With regard to the functional integration of society, material and energy flow analyses can rely on the paradigm of ecological economics and at the same time progress the debate between strong and weak sustainability within the paradigm. However, placing economics at the centre of their functional analyses may still ignore the broader social integration of society, depending on their pre-analytic outline of research and the methods used. (author)

Linking material and energy flow analyses and social theory

International Nuclear Information System (INIS)

Schiller, Frank

2009-01-01

The paper explores the potential of Habermas' theory of communicative action to alter the social reflexivity of material and energy flow analysis. With his social macro theory Habermas has provided an alternative, critical justification for social theory that can be distinguished from economic libertarianism and from political liberalism. Implicitly, most flow approaches draw from these theoretical traditions rather than from discourse theory. There are several types of material and energy flow analyses. While these concepts basically share a system theoretical view, they lack a specific interdisciplinary perspective that ties the fundamental insight of flows to disciplinary scientific development. Instead of simply expanding micro-models to the social macro-dimension social theory suggests infusing the very notion of flows to the progress of disciplines. With regard to the functional integration of society, material and energy flow analyses can rely on the paradigm of ecological economics and at the same time progress the debate between strong and weak sustainability within the paradigm. However, placing economics at the centre of their functional analyses may still ignore the broader social integration of society, depending on their pre-analytic outline of research and the methods used. (author)

Energy Flows in Low-Entropy Complex Systems

Directory of Open Access Journals (Sweden)

Eric J. Chaisson

2015-12-01

Full Text Available Nature’s many complex systems—physical, biological, and cultural—are islands of low-entropy order within increasingly disordered seas of surrounding, high-entropy chaos. Energy is a principal facilitator of the rising complexity of all such systems in the expanding Universe, including galaxies, stars, planets, life, society, and machines. A large amount of empirical evidence—relating neither entropy nor information, rather energy—suggests that an underlying simplicity guides the emergence and growth of complexity among many known, highly varied systems in the 14-billion-year-old Universe, from big bang to humankind. Energy flows are as centrally important to life and society as they are to stars and galaxies. In particular, the quantity energy rate density—the rate of energy flow per unit mass—can be used to explicate in a consistent, uniform, and unifying way a huge collection of diverse complex systems observed throughout Nature. Operationally, those systems able to utilize optimal amounts of energy tend to survive and those that cannot are non-randomly eliminated.

Energy Based Clutter Filtering for Vector Flow Imaging

DEFF Research Database (Denmark)

Villagómez Hoyos, Carlos Armando; Jensen, Jonas; Ewertsen, Caroline

2017-01-01

for obtaining vector flow measurements, since the spectra overlaps at high beam-to-flow angles. In this work a distinct approach is proposed, where the energy of the velocity spectrum is used to differentiate among the two signals. The energy based method is applied by limiting the amplitude of the velocity...... spectrum function to a predetermined threshold. The effect of the clutter filtering is evaluated on a plane wave (PW) scan sequence in combination with transverse oscillation (TO) and directional beamforming (DB) for velocity estimation. The performance of the filter is assessed by comparison...

Research on the flow field of undershot cross-flow water turbines using experiments and numerical analysis

International Nuclear Information System (INIS)

Nishi, Y; Inagaki, T; Li, Y; Omiya, R; Hatano, K

2014-01-01

The purpose of this research is to develop a water turbine appropriate for low-head open channels in order to effectively utilize the unused hydropower energy of rivers and agricultural waterways. The application of the cross-flow runner to open channels as an undershot water turbine has come under consideration and, to this end, a significant simplification was attained by removing the casings. However, the flow field of undershot cross-flow water turbines possesses free surfaces. This means that with the variation in the rotational speed, the water depth around the runner will change and flow field itself is significantly altered. Thus it is necessary to clearly understand the flow fields with free surfaces in order to improve the performance of this turbine. In this research, the performance of this turbine and the flow field were studied through experiments and numerical analysis. The experimental results on the performance of this turbine and the flow field were consistent with the numerical analysis. In addition, the inlet and outlet regions at the first and second stages of this water turbine were clarified

Initial angular momentum and flow in high energy nuclear collisions

Science.gov (United States)

Fries, Rainer J.; Chen, Guangyao; Somanathan, Sidharth

2018-03-01

We study the transfer of angular momentum in high energy nuclear collisions from the colliding nuclei to the region around midrapidity, using the classical approximation of the color glass condensate (CGC) picture. We find that the angular momentum shortly after the collision (up to times ˜1 /Qs , where Qs is the saturation scale) is carried by the "β -type" flow of the initial classical gluon field, introduced by some of us earlier. βi˜μ1∇iμ2-μ2∇iμ1 (i =1 ,2 ) describes the rapidity-odd transverse energy flow and emerges from Gauss's law for gluon fields. Here μ1 and μ2 are the averaged color charge fluctuation densities in the two nuclei, respectively. Interestingly, strong coupling calculations using anti-de Sitter/conformal field theory (AdS/CFT) techniques also find an energy flow term featuring this particular combination of nuclear densities. In classical CGC the order of magnitude of the initial angular momentum per rapidity in the reaction plane, at a time 1 /Qs , is |d L2/d η |≈ RAQs-3ɛ¯0/2 at midrapidity, where RA is the nuclear radius, and ɛ¯0 is the average initial energy density. This result emerges as a cancellation between a vortex of energy flow in the reaction plane aligned with the total angular momentum, and energy shear flow opposed to it. We discuss in detail the process of matching classical Yang-Mills results to fluid dynamics. We will argue that dissipative corrections should not be discarded to ensure that macroscopic conservation laws, e.g., for angular momentum, hold. Viscous fluid dynamics tends to dissipate the shear flow contribution that carries angular momentum in boost-invariant fluid systems. This leads to small residual angular momentum around midrapidity at late times for collisions at high energies.

Energy Division annual progress report for period ending September 30, 1988

International Nuclear Information System (INIS)

1989-06-01

The goals and accomplishments of the Energy Division of Oak Ridge National Laboratory are described in this annual progress report for Fiscal Year (FY) 1988. The Energy Division is a multidisciplinary research organization committed to (1) increasing the knowledge and understanding of the way society makes choices in energy use and energy-using technologies, (2) improving society's understanding of the environmental implications of changes in energy technology, and (3) improving and developing new energy-efficient technologies. The Energy Division's programmatic activities focus on four major areas: (1) analysis and assessment, (2) transportation and decision systems research, (3) technology research and development for improving the efficiency of energy and end-use technologies, and (4) electric power systems. The Division's total expenditures in FY 1988 were $44.3 million. The work is supported by the US Department of Energy, US Department of Defense, many other federal agencies, and some private organizations. Disciplines of the 139 staff members include engineering, social sciences, physical and life sciences, and mathematics and statistics

Flow control in s-shaped air intake diffuser of gas turbine using proposed energy promoters

Directory of Open Access Journals (Sweden)

Jessam Raed A.

2017-01-01

Full Text Available This paper presents an experimental and numerical investigation of the flow control in an air intake S-shaped diffuser with and without energy promoters. The S-shaped diffuser had an area ratio 3.1and turning angle of 45°/45°. The proposed energy promoter was named as stream line sheet energy promoter. Computational Fluid Dynamics simulation was performed through commercial ANSYS-FLUENT 16.2 software. The measurements were made inside annular subsection, 45° from 360° of the complete annular shape of the diffuser, at Reynolds number 5.8×104 and turbulence intensity 4.1%. Results for the bare S-shaped diffuser (without energy promoters showed the flow structures within the S-shaped diffuser were dominated by counter-rotating vortices and boundary layer separation especially in the outer surface. The combination of the adverse pressure gradient at the first bend of outer surface and upstream low momentum wakes caused the boundary layer to separate early. The combinations of proposed energy promoters were installed on the inner and outer surfaces at three installation planes. The use of energy promoters resulting in significantly decreased the outer surface boundary layer separation with consequential improving the static pressure coefficient and reduction of total pressure losses

Energy Demodulation Algorithm for Flow Velocity Measurement of Oil-Gas-Water Three-Phase Flow

Directory of Open Access Journals (Sweden)

Yingwei Li

2014-01-01

Full Text Available Flow velocity measurement was an important research of oil-gas-water three-phase flow parameter measurements. In order to satisfy the increasing demands for flow detection technology, the paper presented a gas-liquid phase flow velocity measurement method which was based on energy demodulation algorithm combing with time delay estimation technology. First, a gas-liquid phase separation method of oil-gas-water three-phase flow based on energy demodulation algorithm and blind signal separation technology was proposed. The separation of oil-gas-water three-phase signals which were sampled by conductance sensor performed well, so the gas-phase signal and the liquid-phase signal were obtained. Second, we used the time delay estimation technology to get the delay time of gas-phase signals and liquid-phase signals, respectively, and the gas-phase velocity and the liquid-phase velocity were derived. At last, the experiment was performed at oil-gas-water three-phase flow loop, and the results indicated that the measurement errors met the need of velocity measurement. So it provided a feasible method for gas-liquid phase velocity measurement of the oil-gas-water three-phase flow.

Environmental benefits of electrification and end-use efficiency

International Nuclear Information System (INIS)

McMenamin, J.S.; Monforte, F.A.; Sioshansi, F.P.

1997-01-01

Significant reductions in greenhouse gases and criteria pollutants can be achieved through continued substitution of clean, efficient electrotechnologies for fossil fuel-based technologies. Continued improvements in the efficiency of electrical appliances already in use will further increase the environmental benefits of electricity. Over the last several decades, electricity use in the US has grown strongly. Over a 35 year period 1960-95, electric utility sales increased more than fourfold, from under 700 billion kWh (BkWh) to almost 3,000 BkWh. This increase was due, in part, to a growing economy, but it also reflects the increasingly broad application of electricity to provide comfort, convenience, entertainment, safety and productivity. Reflecting this expanding role, energy used for electricity generation by utilities has nearly doubled, increasing from 19 percent of US primary energy use in 1960 to about 36 percent in 1995. Environmental factors have also provided support to policies that promote improved end-use efficiency. More efficient end-use equipment allows consumers to obtain the same level of end-use services with less electricity. Reduced electricity consumption levels imply reduced generation requirements and therefore, lower levels of emissions associated with generation. Beginning in the mid-1970's, and stimulated by abrupt increases in fossil fuel prices, both government and utility policies began to emphasize end-use efficiency

Altered Right Ventricular Kinetic Energy Work Density and Viscous Energy Dissipation in Patients with Pulmonary Arterial Hypertension: A Pilot Study Using 4D Flow MRI.

Directory of Open Access Journals (Sweden)

Q Joyce Han

Full Text Available Right ventricular (RV function has increasingly being recognized as an important predictor for morbidity and mortality in patients with pulmonary arterial hypertension (PAH. The increased RV after-load increase RV work in PAH. We used time-resolved 3D phase contrast MRI (4D flow MRI to derive RV kinetic energy (KE work density and energy loss in the pulmonary artery (PA to better characterize RV work in PAH patients.4D flow and standard cardiac cine images were obtained in ten functional class I/II patients with PAH and nine healthy subjects. For each individual, we calculated the RV KE work density and the amount of viscous dissipation in the PA.PAH patients had alterations in flow patterns in both the RV and the PA compared to healthy subjects. PAH subjects had significantly higher RV KE work density than healthy subjects (94.7±33.7 mJ/mL vs. 61.7±14.8 mJ/mL, p = 0.007 as well as a much greater percent PA energy loss (21.1±6.4% vs. 2.2±1.3%, p = 0.0001 throughout the cardiac cycle. RV KE work density and percent PA energy loss had mild and moderate correlations with RV ejection fraction.This study has quantified two kinetic energy metrics to assess RV function using 4D flow. RV KE work density and PA viscous energy loss not only distinguished healthy subjects from patients, but also provided distinction amongst PAH patients. These metrics hold promise as imaging markers for RV function.

Altered Right Ventricular Kinetic Energy Work Density and Viscous Energy Dissipation in Patients with Pulmonary Arterial Hypertension: A Pilot Study Using 4D Flow MRI.

Science.gov (United States)

Han, Q Joyce; Witschey, Walter R T; Fang-Yen, Christopher M; Arkles, Jeffrey S; Barker, Alex J; Forfia, Paul R; Han, Yuchi

2015-01-01

Right ventricular (RV) function has increasingly being recognized as an important predictor for morbidity and mortality in patients with pulmonary arterial hypertension (PAH). The increased RV after-load increase RV work in PAH. We used time-resolved 3D phase contrast MRI (4D flow MRI) to derive RV kinetic energy (KE) work density and energy loss in the pulmonary artery (PA) to better characterize RV work in PAH patients. 4D flow and standard cardiac cine images were obtained in ten functional class I/II patients with PAH and nine healthy subjects. For each individual, we calculated the RV KE work density and the amount of viscous dissipation in the PA. PAH patients had alterations in flow patterns in both the RV and the PA compared to healthy subjects. PAH subjects had significantly higher RV KE work density than healthy subjects (94.7±33.7 mJ/mL vs. 61.7±14.8 mJ/mL, p = 0.007) as well as a much greater percent PA energy loss (21.1±6.4% vs. 2.2±1.3%, p = 0.0001) throughout the cardiac cycle. RV KE work density and percent PA energy loss had mild and moderate correlations with RV ejection fraction. This study has quantified two kinetic energy metrics to assess RV function using 4D flow. RV KE work density and PA viscous energy loss not only distinguished healthy subjects from patients, but also provided distinction amongst PAH patients. These metrics hold promise as imaging markers for RV function.

Flow visualization study of two phase flow in a single bend outlet feeder pipe and horizontal annulus of outlet end-fitting of a CANDU reactor

International Nuclear Information System (INIS)

Supa-Amornkul, S.; Lister, D.H.; Steward, F.R.

2005-01-01

'Full text:' In CANDU-6 reactors, the pressurized high-temperature coolant flows through 380 fuel channels passing horizontally through the core. Each end of a fuel channel has a stainless steel annular end-fitting connected to a carbon steel feeder pipe. The outlet coolant, which is at 310 o C with up to 0.30 steam voidage, turns through 90 o as it passes from flow in the annular end-fitting to pipe flow in the feeder via a Grayloc connector. Since 1996, several CANDU stations have reported excessive corrosion of their outlet feeder pipes; especially between the first metre, which consisted of single or double bends. Early studies related the attack to the hydrodynamics of the coolant and verified that it was a type of flow accelerated corrosion. In order to understand the hydrodynamics of the coolant in the outlet feeders by flow-visualization, a full-scale transparent test section simulating the geometry and orientation of an outlet feeder bend with its upstream annular end-fitting were fabricated. The feeder consisted of a 54 mm inside diameter acrylic pipe with a 73 o bend, connecting to an acrylic simulation of a Grayloc flanged fitting and annular end-fitting. The annular end-fitting consisted of an inner pipe, 110 mm outer diameter, and an outer pipe, 150 mm inner diameter, both 190.7 cm long in length. The tests were performed with water and air at atmospheric pressure and room temperature. The maximum water volumetric flow rate was 19 L/s and the volume fraction of air varied from 0.05 to 0.56. The phase distributions within the feeder pipe and along the length of the annulus were investigated with a digital video recorder. Size, concentration and velocity of the air bubbles at particular locations were studied with a high-speed digital still camera and a high-speed digital video camera. Phase distributions and variations in bubble size with velocity were determined. Particular attention was paid to the flow pattern at the inside of the bend, where a CFD

Flow visualization study of two phase flow in a single bend outlet feeder pipe and horizontal annulus of outlet end-fitting of a CANDU reactor

Energy Technology Data Exchange (ETDEWEB)

Supa-Amornkul, S.; Lister, D.H.; Steward, F.R. [Univ. of New Brunswick, Fredericton, New Brunswick (Canada)]. E-mail: h796e@unb.ca; dlister@unb.ca; fsteward@unb.ca

2005-07-01

'Full text:' In CANDU-6 reactors, the pressurized high-temperature coolant flows through 380 fuel channels passing horizontally through the core. Each end of a fuel channel has a stainless steel annular end-fitting connected to a carbon steel feeder pipe. The outlet coolant, which is at 310{sup o}C with up to 0.30 steam voidage, turns through 90{sup o} as it passes from flow in the annular end-fitting to pipe flow in the feeder via a Grayloc connector. Since 1996, several CANDU stations have reported excessive corrosion of their outlet feeder pipes; especially between the first metre, which consisted of single or double bends. Early studies related the attack to the hydrodynamics of the coolant and verified that it was a type of flow accelerated corrosion. In order to understand the hydrodynamics of the coolant in the outlet feeders by flow-visualization, a full-scale transparent test section simulating the geometry and orientation of an outlet feeder bend with its upstream annular end-fitting were fabricated. The feeder consisted of a 54 mm inside diameter acrylic pipe with a 73{sup o} bend, connecting to an acrylic simulation of a Grayloc flanged fitting and annular end-fitting. The annular end-fitting consisted of an inner pipe, 110 mm outer diameter, and an outer pipe, 150 mm inner diameter, both 190.7 cm long in length. The tests were performed with water and air at atmospheric pressure and room temperature. The maximum water volumetric flow rate was 19 L/s and the volume fraction of air varied from 0.05 to 0.56. The phase distributions within the feeder pipe and along the length of the annulus were investigated with a digital video recorder. Size, concentration and velocity of the air bubbles at particular locations were studied with a high-speed digital still camera and a high-speed digital video camera. Phase distributions and variations in bubble size with velocity were determined. Particular attention was paid to the flow pattern at the inside

Flow imaging of the cardiovascular system using magnetic resonance imaging

International Nuclear Information System (INIS)

Imai, Hitoshi; Sakakibara, Makoto; Sunami, Yuko

1988-01-01

Blood flow images by magnetic resonance imaging (MRI) using a 0.25 T unit were evaluated for nine normal volunteers and 108 subjects with a variety of cardiovascular abnormalities. Using the non-gated short-spin echo (SE) technique, blood flow in the cardiovascular systems was not imaged in the normal volunteers. Using end-systolic and end-diastolic SE techniques for the normal subjects, blood flow in the cardiac chambers was not clearly imaged. Blood flow in the ascending aorta and aortic arch often did not appear in the gated SE images of the normal subjects. However, blood flow in the descending aorta was often observed in the gated SE images. Blood flow imaging was demonstrated by both non-gated and gated SE techniques in regions where blood flow was relatively slow; for example, in the left atrium of mitral stenosis, in an aortic aneurysm, in a false lumen of an aortic dissection, and in the left ventricle having old myocardial infarction. Using the non-gated inversion recovery (IR) technique, no blood flow was imaged in the cardiovascular system except in the left atrium of one case with mitral stenosis. Using the non-gated short SE technique, there was good correlation between the thrombus formation and the presence of blood flow images in the left atria of 17 patients with mitral stenosis, and in the aneurysmal portions of the aorta or in the false lumens of aortic dissection of 18 patients. It was suggested that mural thrombi in such diseases were related to the relatively slow blood flow. Blood flow imaging easily distinguished stagnant blood flow from mural thrombi using non-gated short SE, end-systolic SE, and IR techniques. Thus, blood flow imaging using MRI should become an important means of evaluating the cardiovascular system. (author)

Energy recovery from air flow in underground railway systems

Energy Technology Data Exchange (ETDEWEB)

Morrone, B.; Mariani, A. [Seconda Univ. degli studi di Napoli, Aversa (Italy). Dept. of Aerospace and Mechanical Engineering; Costanzo, M.L. [Tecnosistem spa, Napoli (Italy)

2010-07-01

The 20-20-20 energy policy of the European Union commits members to reduce carbon dioxide (CO{sub 2}) emissions by 20 per cent by 2020, and stipulates that 20 per cent of final-use energy is to be supplied by renewable energy sources. This paper proposed the concept of recovering energy from underground trains by using the air flow inside tunnels to drive energy conversion systems such as turbines to generate electricity. Underground trains use much of their power to overcome the aerodynamic resistance moving the air in front of the train, creating a piston effect when travelling inside tunnels at relatively low speed. Numerical simulations were used in this study to determine how much electricity could be produced. A one-dimensional numerical analysis of a specific subway train track was used to evaluate the air flow magnitude inside the tunnel. Once the air flow features were detected, the potential electricity production was evaluated by considering the characteristics of a Wells turbine. Two types of 3-dimensional models of the tunnel and train were presented. One considered a long straight tunnel with a train running in it, and a small portion of a bypass tunnel. The other considered a large part of an opposite tunnel connected to the main one through the by-pass tunnel. Both the 3D models revealed a maximum flow rate of 2.5 x 105 m{sup 3}/h, while the 1D model showed an air flow of 1.5 x 105 m{sup 3}/h. The difference was due primarily to the presence of fans in the 1D Model and different modelling assumptions. It was concluded that one single Wells type turbine placed in a by-pass tunnel can produce 32.6 kWh per day, or about 10 MWh per year, resulting in a CO{sub 2} savings of about 5.5 tons per year. 8 refs., 1 tab., 11 figs.

Modeling Water Resource Systems Accounting for Water-Related Energy Use, GHG Emissions and Water-Dependent Energy Generation in California

Science.gov (United States)

Escriva-Bou, A.; Lund, J. R.; Pulido-Velazquez, M.; Medellin-Azuara, J.

2015-12-01

Most individual processes relating water and energy interdependence have been assessed in many different ways over the last decade. It is time to step up and include the results of these studies in management by proportionating a tool for integrating these processes in decision-making to effectively understand the tradeoffs between water and energy from management options and scenarios. A simple but powerful decision support system (DSS) for water management is described that includes water-related energy use and GHG emissions not solely from the water operations, but also from final water end uses, including demands from cities, agriculture, environment and the energy sector. Because one of the main drivers of energy use and GHG emissions is water pumping from aquifers, the DSS combines a surface water management model with a simple groundwater model, accounting for their interrelationships. The model also explicitly includes economic data to optimize water use across sectors during shortages and calculate return flows from different uses. Capabilities of the DSS are demonstrated on a case study over California's intertied water system. Results show that urban end uses account for most GHG emissions of the entire water cycle, but large water conveyance produces significant peaks over the summer season. Also the development of more efficient water application on the agricultural sector has increased the total energy consumption and the net water use in the basins.

French people opinion about energy questions at the end of 1992

International Nuclear Information System (INIS)

1993-06-01

This paper presents a statistical study of french people opinion about energy questions at the end of 1992: the main subjects studied are heating energy and the forecasts about the evolution of energy prices. 4 tabs

Energy distribution and transfer in flowing hydrogen microwave plasmas

International Nuclear Information System (INIS)

Chapman, R.A.

1987-01-01

This thesis is an experimental investigation of the physical and chemical properties of a hydrogen discharge in a flowing microwave plasma system. The plasma system is the mechanisms utilized in an electrothermal propulsion concept to convert electromagnetic energy into the kinetic energy of flowing hydrogen gas. The plasmas are generated inside a 20-cm ID resonant cavity at a driving frequency of 2.45 GHz. The flowing gas is contained in a coaxially positioned 22-mm ID quartz discharge tube. The physical and chemical properties are examined for absorbed powers of 20-100 W, pressures of 0.5-10 torr, and flow rates of 0-10,000 μ-moles/sec. A calorimetry system enclosing the plasma system to accurately measure the energy inputs and outputs has been developed. The rate of energy that is transferred to the hydrogen gas as it flows through the plasma system is determined as a function of absorbed power, pressure, and flow rate to +/-1.8 W from an energy balance around the system. The percentage of power that is transferred to the gas is found to increase with increasing flow rate, decrease with increasing pressure, and to be independent of absorbed power

Commercial equipment loads: End-Use Load and Consumer Assessment Program (ELCAP)

Energy Technology Data Exchange (ETDEWEB)

Pratt, R.G.; Williamson, M.A.; Richman, E.E.; Miller, N.E.

1990-07-01

The Office of Energy Resources of the Bonneville Power Administration is generally responsible for the agency's power and conservation resource planning. As associated responsibility which supports a variety of office functions is the analysis of historical trends in and determinants of energy consumption. The Office of Energy Resources' End-Use Research Section operates a comprehensive data collection program to provide pertinent information to support demand-side planning, load forecasting, and demand-side program development and delivery. Part of this on-going program is known as the End-Use Load and Consumer Assessment Program (ELCAP), an effort designed to collect electricity usage data through direct monitoring of end-use loads in buildings. This program is conducted for Bonneville by the Pacific Northwest Laboratory. This report provides detailed information on electricity consumption of miscellaneous equipment from the commercial portion of ELCAP. Miscellaneous equipment includes all commercial end-uses except heating, ventilating, air conditioning, and central lighting systems. Some examples of end-uses covered in this report are office equipment, computers, task lighting, refrigeration, and food preparation. Electricity consumption estimates, in kilowatt-hours per square food per year, are provided for each end-use by building type. The following types of buildings are covered: office, retail, restaurant, grocery, warehouse, school, university, and hotel/motel. 6 refs., 35 figs., 12 tabs.

Exploring energy loss by vector flow mapping in children with ventricular septal defect: Pathophysiologic significance.

Science.gov (United States)

Honda, Takashi; Itatani, Keiichi; Takanashi, Manabu; Kitagawa, Atsushi; Ando, Hisashi; Kimura, Sumito; Oka, Norihiko; Miyaji, Kagami; Ishii, Masahiro

2017-10-01

Vector flow mapping is a novel echocardiographic flow visualization method, and it has enabled us to quantitatively evaluate the energy loss in the left ventricle (intraventricular energy loss). Although intraventricular energy loss is assumed to be a part of left ventricular workload itself, it is unclear what this parameter actually represents. The aim of the present study was to elucidate the characteristics of intraventricular energy loss. We enrolled 26 consecutive children with ventricular septal defect (VSD). On echocardiography vector flow mapping, intraventricular energy loss was measured in the apical 3-chamber view. We measured peak energy loss and averaged energy loss in the diastolic and systolic phases, and subsequently compared these parameters with catheterization parameters and serum brain natrium peptide (BNP) level. Diastolic, peak, and systolic energy loss were strongly and positively correlated with right ventricular systolic pressure (r=0.76, 0.68, and 0.56, p<0.0001, = 0.0001, and 0.0029, respectively) and right ventricular end diastolic pressure (r=0.55, 0.49, and 0.49, p=0.0038, 0.0120, and 0.0111, respectively). In addition, diastolic, peak, and systolic energy loss were significantly correlated with BNP (r=0.75, 0.69 and 0.49, p<0.0001, < 0.0001, and=0.0116, respectively). In children with VSD, elevated right ventricular pressure is one of the factors that increase energy loss in the left ventricle. The results of the present study encourage further studies in other study populations to elucidate the characteristics of intraventricular energy loss for its possible clinical application. Copyright © 2017 Elsevier B.V. All rights reserved.

A new energy transfer model for turbulent free shear flow

Science.gov (United States)

Liou, William W.-W.

1992-01-01

A new model for the energy transfer mechanism in the large-scale turbulent kinetic energy equation is proposed. An estimate of the characteristic length scale of the energy containing large structures is obtained from the wavelength associated with the structures predicted by a weakly nonlinear analysis for turbulent free shear flows. With the inclusion of the proposed energy transfer model, the weakly nonlinear wave models for the turbulent large-scale structures are self-contained and are likely to be independent flow geometries. The model is tested against a plane mixing layer. Reasonably good agreement is achieved. Finally, it is shown by using the Liapunov function method, the balance between the production and the drainage of the kinetic energy of the turbulent large-scale structures is asymptotically stable as their amplitude saturates. The saturation of the wave amplitude provides an alternative indicator for flow self-similarity.

Epistemic uncertainty propagation in energy flows between structural vibrating systems

Science.gov (United States)

Xu, Menghui; Du, Xiaoping; Qiu, Zhiping; Wang, Chong

2016-03-01

A dimension-wise method for predicting fuzzy energy flows between structural vibrating systems coupled by joints with epistemic uncertainties is established. Based on its Legendre polynomial approximation at α=0, both the minimum and maximum point vectors of the energy flow of interest are calculated dimension by dimension within the space spanned by the interval parameters determined by fuzzy those at α=0 and the resulted interval bounds are used to assemble the concerned fuzzy energy flows. Besides the proposed method, vertex method as well as two current methods is also applied. Comparisons among results by different methods are accomplished by two numerical examples and the accuracy of all methods is simultaneously verified by Monte Carlo simulation.

Analysis of the Syrian long-term energy and electricity demand projection using the end-use methodology

International Nuclear Information System (INIS)

Hainoun, A.; Seif-Eldin, M.K.; Almoustafa, S.

2006-01-01

A comprehensive analysis of the possible future long-term development of Syrian energy and electricity demand covering the period 1999-2030 is presented. The analysis was conducted using the IAEA's model MAED, which relies upon the end-use approach. This model has been validated during the last two decades through the successful application in many developing countries, even those having partial market economy and energy subsidy. Starting from the base year, final energy consumption distributed by energy forms and consumption sectors, the future energy and electricity demand has been projected according to three different scenarios reflecting the possible future demographic, socio-economic and technological development of the country. These scenarios are constructed to cover a plausible range, in which future evolution factors affecting energy demand are expected to lie. The first is a high economy scenario (HS) representing the reference case, which is characterized by high gross domestic product (GDP) growth rate (average annual about 6%) and moderate improved technologies in the various consumption sectors. The second is an energy efficiency scenario (ES), which is identical to HS in all main parameters except these relating to the efficiency improvement and conservation measures. Here, high technology improvement and more effective conservation measures in all consumption sectors are proposed and the role of solar to substitute fossil energy for heating purposes is considered effectively. The third is a low economy scenario (LS) with low GDP growth rate (average annual about 3.5%) and less technology improvement in the consumption sectors. As a consequence, the improvement in the energy efficiency is low and the influence of conservation measures is less effective. Starting from about 10.5mtoe final energy in the base year, the analysis shows that the projected energy demand will grow annually at average rates of 5%, 4.5% and 3% for the HS, ES and LS

Functional efficiency comparison between split- and parallel-hybrid using advanced energy flow analysis methods

Energy Technology Data Exchange (ETDEWEB)

Guttenberg, Philipp; Lin, Mengyan [Romax Technology, Nottingham (United Kingdom)

2009-07-01

The following paper presents a comparative efficiency analysis of the Toyota Prius versus the Honda Insight using advanced Energy Flow Analysis methods. The sample study shows that even very different hybrid concepts like a split- and a parallel-hybrid can be compared in a high level of detail and demonstrates the benefit showing exemplary results. (orig.)

Energy Cascade Analysis: from Subscale Eddies to Mean Flow

Science.gov (United States)

Cheikh, Mohamad Ibrahim; Wonnell, Louis; Chen, James

2017-11-01

Understanding the energy transfer between eddies and mean flow can provide insights into the energy cascade process. Much work has been done to investigate the energy cascade at the level of the smallest eddies using different numerical techniques derived from the Navier-Stokes equations. These methodologies, however, prove to be computationally inefficient when producing energy spectra for a wide range of length scales. In this regard, Morphing Continuum Theory (MCT) resolves the length-scales issues by assuming the fluid continuum to be composed of inner structures that play the role of subscale eddies. The current study show- cases the capabilities of MCT in capturing the dynamics of energy cascade at the level of subscale eddies, through a supersonic turbulent flow of Mach 2.93 over an 8× compression ramp. Analysis of the results using statistical averaging procedure shows the existence of a statistical coupling of the internal and translational kinetic energy fluctuations with the corresponding rotational kinetic energy of the subscale eddies, indicating a multiscale transfer of energy. The results show that MCT gives a new characterization of the energy cascade within compressible turbulence without the use of excessive computational resources. This material is based upon work supported by the Air Force Office of Scientific Research under Award Number FA9550-17-1-0154.

TEMPO-based catholyte for high-energy density nonaqueous redox flow batteries.

Science.gov (United States)

Wei, Xiaoliang; Xu, Wu; Vijayakumar, Murugesan; Cosimbescu, Lelia; Liu, Tianbiao; Sprenkle, Vincent; Wang, Wei

2014-12-03

A TEMPO-based non-aqueous electrolyte with the TEMPO concentration as high as 2.0 m is demonstrated as a high-energy-density catholyte for redox flow battery applications. With a hybrid anode, Li|TEMPO flow cells using this electrolyte deliver an energy efficiency of ca. 70% and an impressively high energy density of 126 W h L(-1) . © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Management of Energy Flows in Low-temperature Separation Units

Directory of Open Access Journals (Sweden)

Trishyn F.A.

2018-04-01

Full Text Available . The aim of this work is to study the effect of medium and low power ultrasound on the crystallization and separation processes. A thesis about the importance of using thermal energy converters in separation units has been suggested. The prospects of desalination freezing units and ways of their improvement have been justified. Based on the system analysis, the energy flows in an ice recycling facility have been considered. For the first time, the overall energy efficiency estimation technique based on the hypothesis of direct and reverse energy flows has been proposed. The new results on the effect of ultrasonic fields on the separation and crystallization process have been obtained. It has been proved that the use of ultrasonic field is effective in controlling the energy flows during block freezing. It has been established that the salt content in the ice block is reduced by 2-3 times. The relationship between the ice block separation kinetics and the power and frequency has been determined. The similarity theory methods have been used to summarize the experimental data obtained. The criterion models have been presented to calculate the block porosity and the filtration rate. It has been established that the Euler wavenumber modified by the authors successfully generalizes the databases of the experimental findings. Using the numerical simulation methods, the thermal field in the block which depends on its porosity has been established. The results of the simulation have been presented in the form of a nomogram.

Flow Energy Piezoelectric Bimorph Nozzle Harvester

Science.gov (United States)

Sherrit, Stewart (Inventor); Walkemeyer, Phillip E. (Inventor); Hall, Jeffrey L. (Inventor); Lee, Hyeong Jae (Inventor); Colonius, Tim (Inventor); Tosi, Phillipe (Inventor); Kim, Namhyo (Inventor); Sun, Kai (Inventor); Corbett, Thomas Gary (Inventor); Arrazola, Alvaro Jose (Inventor)

2016-01-01

A flow energy harvesting device having a harvester pipe includes a flow inlet that receives flow from a primary pipe, a flow outlet that returns the flow into the primary pipe, and a flow diverter within the harvester pipe having an inlet section coupled to the flow inlet, a flow constriction section coupled to the inlet section and positioned at a midpoint of the harvester pipe and having a spline shape with a substantially reduced flow opening size at a constriction point along the spline shape, and an outlet section coupled to the constriction section. The harvester pipe may further include a piezoelectric structure extending from the inlet section through the constriction section and point such that the fluid flow past the constriction point results in oscillatory pressure amplitude inducing vibrations in the piezoelectric structure sufficient to cause a direct piezoelectric effect and to generate electrical power for harvesting.

Global flow of glasma in high energy nuclear collisions

Energy Technology Data Exchange (ETDEWEB)

Chen, Guangyao; Fries, Rainer J., E-mail: rjfries@comp.tamu.edu

2013-06-25

We discuss the energy flow of the classical gluon fields created in collisions of heavy nuclei at collider energies. We show how the Yang–Mills analog of Faraday's Law and Gauss' Law predicts the initial gluon flux tubes to expand or bend. The resulting transverse and longitudinal structure of the Poynting vector field has a rich phenomenology. Besides the well-known radial and elliptic flow in transverse direction, classical quantum chromodynamics predicts a rapidity-odd transverse flow that tilts the fireball for non-central collisions, and it implies a characteristic flow pattern for collisions of non-symmetric systems A+B. The rapidity-odd transverse flow translates into a directed particle flow v{sub 1} which has been observed at RHIC and LHC. The global flow fields in heavy ion collisions could be a powerful check for the validity of classical Yang–Mills dynamics in high energy collisions.

Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

International Nuclear Information System (INIS)

Matthews, W.

2000-01-01

Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results from each project

Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

Energy Technology Data Exchange (ETDEWEB)

Matthews, W.

2000-02-22

Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results

Direct observation of vibrational energy flow in cytochrome c.

Science.gov (United States)

Fujii, Naoki; Mizuno, Misao; Mizutani, Yasuhisa

2011-11-10

Vibrational energy flow in ferric cytochrome c has been examined by picosecond time-resolved anti-Stokes ultraviolet resonance Raman (UVRR) measurements. By taking advantage of the extremely short nonradiative excited state lifetime of heme in the protein (energy of 20000-25000 cm(-1) was optically deposited selectively at the heme site. Subsequent energy relaxation in the protein moiety was investigated by monitoring the anti-Stokes UVRR intensities of the Trp59 residue, which is a single tryptophan residue involved in the protein that is located close to the heme group. It was found from temporal changes of the anti-Stokes UVRR intensities that the energy flow from the heme to Trp59 and the energy release from Trp59 took place with the time constants of 1-3 and ~8 ps, respectively. These data are consistent with the time constants for the vibrational relaxation of the heme and heating of water reported for hemeproteins. The kinetics of the energy flow were not affected by the amount of excess energy deposited at the heme group. These results demonstrate that the present technique is a powerful tool for studying the vibrational energy flow in proteins.

Analysis of multiphase flows using dual-energy gamma densitometry and neural networks

International Nuclear Information System (INIS)

Bishop, C.M.; James, G.D.

1993-01-01

Dual-energy gamma densitometry offers a powerful technique for the non-intrusive analysis of multiphase flows. By employing multiple beam lines, information on the phase configuration can be obtained. Once the configuration is known, it then becomes possible in principle to determine the phase fractions. In practice, however, the extraction of the phase fractions from the densitometer data is complicated by the wide variety of phase configurations which can arise, and by the considerable difficulties of modelling multiphase flows. In this paper we show that neural network techniques provide a powerful approach to the analysis of data from dual-energy gamma densitometers, allowing both the phase configuration and the phase fractions to be determined with high accuracy, whilst avoiding the uncertainties associated with modelling. The technique is well suited to the determination of oil, water and gas fractions in multiphase oil pipelines. Results from linear and non-linear network models are compared, and a new technique for validating the network output is described. (orig.)

Optimal energy growth in a stably stratified shear flow

Science.gov (United States)

Jose, Sharath; Roy, Anubhab; Bale, Rahul; Iyer, Krithika; Govindarajan, Rama

2018-02-01

Transient growth of perturbations by a linear non-modal evolution is studied here in a stably stratified bounded Couette flow. The density stratification is linear. Classical inviscid stability theory states that a parallel shear flow is stable to exponentially growing disturbances if the Richardson number (Ri) is greater than 1/4 everywhere in the flow. Experiments and numerical simulations at higher Ri show however that algebraically growing disturbances can lead to transient amplification. The complexity of a stably stratified shear flow stems from its ability to combine this transient amplification with propagating internal gravity waves (IGWs). The optimal perturbations associated with maximum energy amplification are numerically obtained at intermediate Reynolds numbers. It is shown that in this wall-bounded flow, the three-dimensional optimal perturbations are oblique, unlike in unstratified flow. A partitioning of energy into kinetic and potential helps in understanding the exchange of energies and how it modifies the transient growth. We show that the apportionment between potential and kinetic energy depends, in an interesting manner, on the Richardson number, and on time, as the transient growth proceeds from an optimal perturbation. The oft-quoted stabilizing role of stratification is also probed in the non-diffusive limit in the context of disturbance energy amplification.

Bootstrapping the energy flow in the beginning of life

NARCIS (Netherlands)

Hengeveld, R.; Fedonkin, M.A.

2007-01-01

This paper suggests that the energy flow on which all living structures depend only started up slowly, the low-energy, initial phase starting up a second, slightly more energetic phase, and so on. In this way, the build up of the energy flow follows a bootstrapping process similar to that found in

Bootstrapping the energy flow in the beginning of life.

NARCIS (Netherlands)

Hengeveld, R.; Fedonkin, M.A.

2007-01-01

This paper suggests that the energy flow on which all living structures depend only started up slowly, the low-energy, initial phase starting up a second, slightly more energetic phase, and so on. In this way, the build up of the energy flow follows a bootstrapping process similar to that found in

Analysis of cantilever pipes in transverse fluid flow with motion limiting stopper at the free end

International Nuclear Information System (INIS)

Jiyavan, R.

1983-01-01

Flow-induced vibration in heat exchanger tubes can result in impact with the baffle plates and subsequent tube failure through fatigue, fracture and fretting wear. As a step towards the correlation between the random flow excitations and the rate of wear, this paper presents a general theory for predicting the tube motion and the tube baffle impact forces through a case of cantilever pipe with motion limiting stopper at the free end and simultaneously subjected to transverse fluid flow. The mathematical model has been developed using the theory of fluid-structure interactions with model superposition technique. The pipe displacement induced by lift forces is evaluated by numerical integration. When displacement increases to greater than the pipe-stopper clearance, the pipe impacts on stopper. Assuming semielastic impact, the equation of pipe motion during impact is developed using extended Hertz's theory to include the vibration of one of the colliding bodies. The stopper is assumed to be at rest before and after the impact. The constraint imposed on pipe motion, at the free end due to impact of the pipe on stopper, is considered as one of the boundary conditions and is used to evaluate the pipe natural frequencies. The nonlinear equations are solved numerically. The response of the pipe due to wake induced lift forces superposed by the impact response is evaluated. (orig./GL)

California energy flow in 1979

Science.gov (United States)

Briggs, C. K.; Borg, I. Y.

1981-03-01

Energy use in California during 1979 differed significantly from 1978. Overall use of natural gas in the state increased substantially (14.3%) due principally to greater use for electrical power production; 4% more gas was used for electrical power generation in 1979 than in 1978 and 21% more than in 1977. Use of fuel oil for electrical generation remained at the 1978 level but below the high 1977 level, which reflected substitution of oil for hydroelectric power during the 1976 to 1977 drought. Together, oil and gas accounted for 80% of the fuels used to generate electricity. Crude-oil imports principally from Indonesia fell substantially; however, use of Alaskan North Slope oil increased so that the net increase in crude oil use was up about 4%. The transportation end-use sector consumed about as much as in 1978 despite shortages in early 1979 associated with the Iranian revolution. While sales fell slightly, sales of high-sulfur residual oils (Bunker C) increased markedly. Transportation represents 38% of total energy consumption in California.

Energy flow modeling and optimal operation analysis of the micro energy grid based on energy hub

International Nuclear Information System (INIS)

Ma, Tengfei; Wu, Junyong; Hao, Liangliang

2017-01-01

Highlights: • Design a novel architecture for energy hub integrating power hub, cooling hub and heating hub. • The micro energy grid based on energy hub is introduced and its advantages are discussed. • Propose a generic modeling method for the energy flow of micro energy grid. • Propose an optimal operation model for micro energy grid with considering demand response. • The roles of renewable energy, energy storage devices and demand response are discussed separately. - Abstract: The energy security and environmental problems impel people to explore a more efficient, environment friendly and economical energy utilization pattern. In this paper, the coordinated operation and optimal dispatch strategies for multiple energy system are studied at the whole Micro Energy Grid level. To augment the operation flexibility of energy hub, the innovation sub-energy hub structure including power hub, heating hub and cooling hub is put forward. Basing on it, a generic energy hub architecture integrating renewable energy, combined cooling heating and power, and energy storage devices is developed. Moreover, a generic modeling method for the energy flow of micro energy grid is proposed. To minimize the daily operation cost, a day-ahead dynamic optimal operation model is formulated as a mixed integer linear programming optimization problem with considering the demand response. Case studies are undertaken on a community Micro Energy Grid in four different scenarios on a typical summer day and the roles of renewable energy, energy storage devices and demand response are discussed separately. Numerical simulation results indicate that the proposed energy flow modeling and optimal operation method are universal and effective over the entire energy dispatching horizon.

A Variable Flow Modelling Approach To Military End Strength Planning

Science.gov (United States)

2016-12-01

function. The MLRPS is more complex than the variable flow model as it has to cater for a force structure that is much larger than just the MT branch...essential positions in a Ship’s complement, or by the biggest current deficit in forecast end strength. The model can be adjusted to cater for any of these...is unlikely that the RAN will be able to cater for such an increase in hires, so this scenario is not likely to solve their problem. Each transition

Radial collective flow in heavy-ion collisions at intermediate energies

International Nuclear Information System (INIS)

Borderie, B.

1996-11-01

The production of radial collective flow is associated with collisions leading to sources which undergo multifragmentation/explosion processes. After a theoretical survey of possible causes of production of radial flow, methods used to derive experimental values are discussed. Finally, a large set of data is presented which can be used to study and disentangle the different effects leading to radial collective flow. The dominant role of compression in the lower energy domain is emphasized. (author)

Vibrational energy flow in the villin headpiece subdomain: Master equation simulations

Energy Technology Data Exchange (ETDEWEB)

Leitner, David M., E-mail: dml@unr.edu, E-mail: stock@physik.uni-freiburg.de [Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, Nevada 89557 (United States); Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Freiburg (Germany); Buchenberg, Sebastian; Brettel, Paul [Biomolecular Dynamics, Institute of Physics, University of Freiburg, Freiburg (Germany); Stock, Gerhard, E-mail: dml@unr.edu, E-mail: stock@physik.uni-freiburg.de [Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Freiburg (Germany); Biomolecular Dynamics, Institute of Physics, University of Freiburg, Freiburg (Germany)

2015-02-21

We examine vibrational energy flow in dehydrated and hydrated villin headpiece subdomain HP36 by master equation simulations. Transition rates used in the simulations are obtained from communication maps calculated for HP36. In addition to energy flow along the main chain, we identify pathways for energy transport in HP36 via hydrogen bonding between residues quite far in sequence space. The results of the master equation simulations compare well with all-atom non-equilibrium simulations to about 1 ps following initial excitation of the protein, and quite well at long times, though for some residues we observe deviations between the master equation and all-atom simulations at intermediate times from about 1–10 ps. Those deviations are less noticeable for hydrated than dehydrated HP36 due to energy flow into the water.

Vibrational energy flow in the villin headpiece subdomain: Master equation simulations

International Nuclear Information System (INIS)

Leitner, David M.; Buchenberg, Sebastian; Brettel, Paul; Stock, Gerhard

2015-01-01

We examine vibrational energy flow in dehydrated and hydrated villin headpiece subdomain HP36 by master equation simulations. Transition rates used in the simulations are obtained from communication maps calculated for HP36. In addition to energy flow along the main chain, we identify pathways for energy transport in HP36 via hydrogen bonding between residues quite far in sequence space. The results of the master equation simulations compare well with all-atom non-equilibrium simulations to about 1 ps following initial excitation of the protein, and quite well at long times, though for some residues we observe deviations between the master equation and all-atom simulations at intermediate times from about 1–10 ps. Those deviations are less noticeable for hydrated than dehydrated HP36 due to energy flow into the water

The impact of domestic trade on China's regional energy uses: A multi-regional input–output modeling

International Nuclear Information System (INIS)

Zhang, Bo; Chen, Z.M.; Xia, X.H.; Xu, X.Y.; Chen, Y.B.

2013-01-01

To systematically reveal how domestic trade impacts on China's regional energy uses, an interprovincial input–output modeling is carried out to address demand-derived energy requirements for the regional economies in 2007 based on the recently available data. Both the energy uses embodied in final demand and interregional trade are investigated from the regional and sectoral insights. Significant net transfers of embodied energy flows are identified from the central and western areas to the eastern area via interregional trade. Shanxi is the largest energy producer and interregional embodied energy deficit receiver, in contrast to Guangdong as the largest energy user and surplus receiver. By considering the impacts of interregional trade, the energy uses of most eastern regions increase remarkably. For instance, Shanghai, Hainan, Zhejiang, Beijing, Jiangsu and Guangdong have their embodied energy requirements 87.49, 19.97, 13.64, 12.60, 6.46 and 6.38 times of their direct energy inputs, respectively. In contrast, the embodied energy uses of some central and western regions such as Inner Mongolia, Shanxi, Xinjiang, Shaanxi and Guizhou decrease largely. The results help understand the hidden network linkages of interregional embodied energy flows and provide critical insight to amend China's current end-reduction-oriented energy policies by addressing the problem of regional responsibility transfer. - Highlights: • Demand-derived energy requirements for China's regional economies are addressed. • Significant interregional transfers of embodied energy flows are identified. • Energy surpluses are obtained by 19 regions and deficits by the other 11 regions. • The eastern regions should take more responsibility for reducing China's energy uses

Combining interviewing and modeling for end-user energy conservation

International Nuclear Information System (INIS)

Goldblatt, David L.; Hartmann, Christoph; Duerrenberger, Gregor

2005-01-01

Studying energy consumption through the lens of households is an increasingly popular research avenue. This paper focuses on residential end-user energy conservation. It describes an approach that combines energy modeling and in-depth interviews for communicating about energy use and revealing consumer preferences for change at different levels and intervention points. Expert knowledge was embodied in a computer model for householders that calculates an individual's current energy consumption and helps assess personal savings potentials, while also bringing in socio-technical and economic elements beyond the user's direct control. The paper gives a detailed account of this computer information tool developed for interviewing purposes. It then describes the interview guidelines, data analysis, and main results. In general, interview subjects overestimated the environmental friendliness of their lifestyles. After experience with the program, they tended to rate external (technological, societal) factors as somewhat stronger determinants of their consumption levels than personal (behavioral and household investment) factors, with the notable exception of mobility. Concerning long-term energy perspectives, the majority of subjects felt that society has the ability to make a collective choice towards significantly lower energy consumption levels. Interviewees confirmed that the software and interactive sessions helped them think more holistically about the personal, social, and technological dimensions of energy conservation. Lessons can be applied to the development of future energy communication tools

An energy signature scheme for steam trap assessment and flow rate estimation using pipe-induced acoustic measurements

Science.gov (United States)

Olama, Mohammed M.; Allgood, Glenn O.; Kuruganti, Teja P.; Lake, Joe E.

2012-06-01

The US Congress has passed legislation dictating that all government agencies establish a plan and process for improving energy efficiencies at their sites. In response to this legislation, Oak Ridge National Laboratory (ORNL) has recently conducted a pilot study to explore the deployment of a wireless sensor system for a real-time measurement-based energy efficiency optimization framework within the steam distribution system within the ORNL campus. We make assessments on the real-time status of the distribution system by observing the state measurements of acoustic sensors mounted on the steam pipes/traps/valves. In this paper, we describe a spectral-based energy signature scheme that interprets acoustic vibration sensor data to estimate steam flow rates and assess steam traps health status. Experimental results show that the energy signature scheme has the potential to identify different steam trap health status and it has sufficient sensitivity to estimate steam flow rate. Moreover, results indicate a nearly quadratic relationship over the test region between the overall energy signature factor and flow rate in the pipe. The analysis based on estimated steam flow and steam trap status helps generate alerts that enable operators and maintenance personnel to take remedial action. The goal is to achieve significant energy-saving in steam lines by monitoring and acting on leaking steam pipes/traps/valves.

Irreversible energy flow in forced Vlasov dynamics

KAUST Repository

Plunk, Gabriel G.; Parker, Joseph T.

2014-01-01

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag. The recent paper of Plunk [G.G. Plunk, Phys. Plasmas 20, 032304 (2013)] considered the forced linear Vlasov equation as a model for the quasi-steady state of a single stable plasma wavenumber interacting with a bath of turbulent fluctuations. This approach gives some insight into possible energy flows without solving for nonlinear dynamics. The central result of the present work is that the forced linear Vlasov equation exhibits asymptotically zero (irreversible) dissipation to all orders under a detuning of the forcing frequency and the characteristic frequency associated with particle streaming. We first prove this by direct calculation, tracking energy flow in terms of certain exact conservation laws of the linear (collisionless) Vlasov equation. Then we analyze the steady-state solutions in detail using a weakly collisional Hermite-moment formulation, and compare with numerical solution. This leads to a detailed description of the Hermite energy spectrum, and a proof of no dissipation at all orders, complementing the collisionless Vlasov result.

Irreversible energy flow in forced Vlasov dynamics

KAUST Repository

Plunk, Gabriel G.

2014-10-01

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag. The recent paper of Plunk [G.G. Plunk, Phys. Plasmas 20, 032304 (2013)] considered the forced linear Vlasov equation as a model for the quasi-steady state of a single stable plasma wavenumber interacting with a bath of turbulent fluctuations. This approach gives some insight into possible energy flows without solving for nonlinear dynamics. The central result of the present work is that the forced linear Vlasov equation exhibits asymptotically zero (irreversible) dissipation to all orders under a detuning of the forcing frequency and the characteristic frequency associated with particle streaming. We first prove this by direct calculation, tracking energy flow in terms of certain exact conservation laws of the linear (collisionless) Vlasov equation. Then we analyze the steady-state solutions in detail using a weakly collisional Hermite-moment formulation, and compare with numerical solution. This leads to a detailed description of the Hermite energy spectrum, and a proof of no dissipation at all orders, complementing the collisionless Vlasov result.

Centrality dependence of multiplicity, transverse energy, and elliptic flow from hydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Kolb, Peter F.; Heinz, Ulrich; Huovinen, Pasi; Eskola, Kari J.; Tuominen, Kimmo

2001-03-21

The centrality dependence of the charged multiplicity, transverse energy, and elliptic flow coefficient is studied in a hydrodynamic model, using a variety of different initializations which model the initial energy or entropy production process as a hard or soft process, respectively. While the charged multiplicity depends strongly on the chosen initialization, the p{sub T}-integrated elliptic flow for charged particles as a function of charged particle multiplicity and the p{sub T}-differential elliptic flow for charged particles in minimum bias events turn out to be almost independent of the initialization.

Acoustics flow analysis in circular duct using sound intensity and dynamic mode decomposition

International Nuclear Information System (INIS)

Weyna, S

2014-01-01

Sound intensity generation in hard-walled duct with acoustic flow (no mean-flow) is treated experimentally and shown graphically. In paper, numerous methods of visualization illustrating the vortex flow (2D, 3D) can graphically explain diffraction and scattering phenomena occurring inside the duct and around open end area. Sound intensity investigation in annular duct gives a physical picture of sound waves in any duct mode. In the paper, modal energy analysis are discussed with particular reference to acoustics acoustic orthogonal decomposition (AOD). The image of sound intensity fields before and above 'cut-off' frequency region are found to compare acoustic modes which might resonate in duct. The experimental results show also the effects of axial and swirling flow. However acoustic field is extremely complicated, because pressures in non-propagating (cut-off) modes cooperate with the particle velocities in propagating modes, and vice versa. Measurement in cylindrical duct demonstrates also the cut-off phenomenon and the effect of reflection from open end. The aim of experimental study was to obtain information on low Mach number flows in ducts in order to improve physical understanding and validate theoretical CFD and CAA models that still may be improved.

The Redox Flow System for solar photovoltaic energy storage

Science.gov (United States)

Odonnell, P.; Gahn, R. F.; Pfeiffer, W.

1976-01-01

The interfacing of a Solar Photovoltaic System and a Redox Flow System for storage was workable. The Redox Flow System, which utilizes the oxidation-reduction capability of two redox couples, in this case iron and titanium, for its storage capacity, gave a relatively constant output regardless of solar activity so that a load could be run continually day and night utilizing the sun's energy. One portion of the system was connected to a bank of solar cells to electrochemically charge the solutions, while a separate part of the system was used to electrochemically discharge the stored energy.

Sex differences of human cortical blood flow and energy metabolism.

Science.gov (United States)

Aanerud, Joel; Borghammer, Per; Rodell, Anders; Jónsdottir, Kristjana Y; Gjedde, Albert

2017-07-01

Brain energy metabolism is held to reflect energy demanding processes in neuropil related to the density and activity of synapses. There is recent evidence that men have higher density of synapses in temporal cortex than women. One consequence of these differences would be different rates of cortical energy turnover and blood flow in men and women. To test the hypotheses that rates of oxygen consumption (CMRO 2 ) and cerebral blood flow are higher in men than in women in regions of cerebral cortex, and that the differences persist with aging, we used positron emission tomography to determine cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes. Cerebral metabolic rate of oxygen did not change with age for either sex and there were no differences of mean values of cerebral metabolic rate of oxygen between men and women in cerebral cortex. Women had significant decreases of cerebral blood flow as function of age in frontal and parietal lobes. Young women had significantly higher cerebral blood flow than men in frontal and temporal lobes, but these differences had disappeared at age 65. The absent sex difference of cerebral energy turnover suggests that the known differences of synaptic density between the sexes are counteracted by opposite differences of individual synaptic activity.

IMPACT OF THE COLD END OPERATING CONDITIONS ON ENERGY EFFICIENCY OF THE STEAM POWER PLANTS

Directory of Open Access Journals (Sweden)

Slobodan Laković

2010-01-01

Full Text Available The conventional steam power plant working under the Rankine Cycle and the steam condenser as a heat sink and the steam boiler as a heat source have the same importance for the power plant operating process. Energy efficiency of the coal fired power plant strongly depends on its turbine-condenser system operation mode. For the given thermal power plant configuration, cooling water temperature or/and flow rate change generate alterations in the condenser pressure. Those changes have great influence on the energy efficiency of the plant. This paper focuses on the influence of the cooling water temperature and flow rate on the condenser performance, and thus on the specific heat rate of the coal fired plant and its energy efficiency. Reference plant is working under turbine-follow mode with an open cycle cooling system. Analysis is done using thermodynamic theory, in order to define heat load dependence on the cooling water temperature and flow rate. Having these correlations, for given cooling water temperature it is possible to determine optimal flow rate of the cooling water in order to achieve an optimal condensing pressure, and thus, optimal energy efficiency of the plant. Obtained results could be used as useful guidelines in improving existing power plants performances and also in design of the new power plants.

Energy flow and mineral cycling mechanisms

International Nuclear Information System (INIS)

Rogers, L.E.

1977-01-01

Analysis of energy flow patterns and mineral cycling mechanisms provides a first step in identifying major transport pathways away from waste management areas. A preliminary food web pattern is described using results from ongoing and completed food habit studies. Biota possessing the greatest potential for introducing radionuclides into food chains leading to man include deer, rabbits, hares, waterfowl, honeybees and upland game birds and are discussed separately

Workshop on energy data of developing countries. Volume II. Basic energy statistics and energy balances of developing countries, 1967 to 1977

Energy Technology Data Exchange (ETDEWEB)

1979-01-01

Extensive data on energy sources and balances are presented for Algeria, Argentina, Brazil, Colombia, Egypt, India, Indonesia, Iran, Jamaica, Kenya, Republic of Korea, Mexico, Nigeria, Saudi Arabia, Thailand, and Venezuela. Domestic consumption, final consumption, and energy end uses by the various sectors of consumer transactions are indicated. Data are compiled on imports and exports, production, and flows of fuels (processes to provide another energy commodity).

Energy efficient SDN commodity switch based practical flow forwarding method

KAUST Repository

AlGhadhban, Amer

2016-07-04

Recent SDN researches suffer from over-accumulation of unhealthy flow-load. Instead, we leverage the SDN controller network view to encode the end-to-end path information into the packet address. Our solution EncPath significantly reduces the flow-table size and the number of control messages. Consequently, the power consumption of network switches is in orders of magnitude less than other evaluated solutions. It also provides flow management flexibility and scalability. We compare EncPath with single and multipath routing solutions and single path solution. Also, we operated them in proactive and reactive modes. We find that EncPath flow entries in core switches in a multihomed fat-tree with 144 hosts is approximately 1000 times smaller than Equal-Cost MultiPath (ECMP) and random routing. Additionally, the number of control messages to setup the network is reduced by a factor of 200×. This, consequently, affords data-plane and control-plane devices space to process other tasks. © 2016 IEEE.

Mitigating Dam Impacts Using Environmental Flow Releases

Science.gov (United States)

Richter, B. D.

2017-12-01

One of the most ecologically disruptive impacts of dams is their alteration of natural river flow variability. Opportunities exist for modifying the operations of existing dams to recover many of the environmental and social benefits of healthy ecosystems that have been compromised by present modes of dam operation. The potential benefits of dam "re-operation" include recovery of fish, shellfish, and other wildlife populations valued both commercially and recreationally, including estuarine species; reactivation of the flood storage and water purification benefits that occur when floods are allowed to flow into floodplain forests and wetlands; regaining some semblance of the naturally dynamic balance between river erosion and sedimentation that shapes physical habitat complexity, and arresting problems associated with geomorphic imbalances; cultural and spiritual uses of rivers; and many other socially valued products and services. Assessing the potential benefits of dam re-operation begins by characterizing the dam's effects on the river flow regime, and formulating hypotheses about the ecological and social benefits that might be restored by releasing water from the dam in a manner that more closely resembles natural flow patterns. These hypotheses can be tested by implementing a re-operation plan, tracking the response of the ecosystem, and continually refining dam operations through adaptive management. This presentation will highlight a number of land and water management strategies useful in implementing a dam re-operation plan, with reference to a variety of management contexts ranging from individual dams to cascades of dams along a river to regional energy grids. Because many of the suggested strategies for dam re-operation are predicated on changes in the end-use of the water, such as reductions in urban or agricultural water use during droughts, a systemic perspective of entire water management systems will be required to attain the fullest possible

Technology data characterizing refrigeration in commercial buildings: Application to end-use forecasting with COMMEND 4.0

Energy Technology Data Exchange (ETDEWEB)

Sezgen, O.; Koomey, J.G.

1995-12-01

In the United States, energy consumption is increasing most rapidly in the commercial sector. Consequently, the commercial sector is becoming an increasingly important target for state and federal energy policies and also for utility-sponsored demand side management (DSM) programs. The rapid growth in commercial-sector energy consumption also makes it important for analysts working on energy policy and DSM issues to have access to energy end-use forecasting models that include more detailed representations of energy-using technologies in the commercial sector. These new forecasting models disaggregate energy consumption not only by fuel type, end use, and building type, but also by specific technology. The disaggregation of the refrigeration end use in terms of specific technologies, however, is complicated by several factors. First, the number of configurations of refrigeration cases and systems is quite large. Also, energy use is a complex function of the refrigeration-case properties and the refrigeration-system properties. The Electric Power Research Institute`s (EPRI`s) Commercial End-Use Planning System (COMMEND 4.0) and the associated data development presented in this report attempt to address the above complications and create a consistent forecasting framework. Expanding end-use forecasting models so that they address individual technology options requires characterization of the present floorstock in terms of service requirements, energy technologies used, and cost-efficiency attributes of the energy technologies that consumers may choose for new buildings and retrofits. This report describes the process by which we collected refrigeration technology data. The data were generated for COMMEND 4.0 but are also generally applicable to other end-use forecasting frameworks for the commercial sector.

Estimated United States Transportation Energy Use 2005

Energy Technology Data Exchange (ETDEWEB)

Smith, C A; Simon, A J; Belles, R D

2011-11-09

A flow chart depicting energy flow in the transportation sector of the United States economy in 2005 has been constructed from publicly available data and estimates of national energy use patterns. Approximately 31,000 trillion British Thermal Units (trBTUs) of energy were used throughout the United States in transportation activities. Vehicles used in these activities include automobiles, motorcycles, trucks, buses, airplanes, rail, and ships. The transportation sector is powered primarily by petroleum-derived fuels (gasoline, diesel and jet fuel). Biomass-derived fuels, electricity and natural gas-derived fuels are also used. The flow patterns represent a comprehensive systems view of energy used within the transportation sector.

Data on flow cell optimization for membrane-based electrokinetic energy conversion

Directory of Open Access Journals (Sweden)

David Nicolas Østedgaard-Munck

2017-12-01

Full Text Available This article elaborates on the design and optimization of a specialized flow cell for the measurement of direct conversion of pressure into electrical energy (Electrokinetic Energy Conversion, EKEC which has been presented in Østedgaard-Munck et al. (2017 [1]. Two main flow cell parameters have been monitored and optimized: A the hydraulic pressure profile on each side of the membrane introduced by pumps recirculating the electrolyte solution through the flow fields and B the electrical resistance between the current collectors across the combined flow cell. The latter parameter has been measured using four-point Electrochemical Impedance spectroscopy (EIS for different flow rates and concentrations. The total cell resistance consists of contributions from different components: the membrane (Rmem, anode charge transfer (RA, cathode charge transfer (RC, and ion diffusion in the porous electrodes (RD.The intrinsic membrane properties of Nafion 117 has been investigated experimentally in LiI/I2 solutions with concentrations ranging between 0.06 and 0.96 M and used to identify the preferred LiI/I2 solution concentration. This was achieved by measuring the solution uptake, internal solution concentration and ion exchange capacity. The membrane properties were further used to calculate the transport coefficients and electrokinetic Figure of merit in terms of the Uniform potential and Space charge models. Special attention has been put on the streaming potential coefficient which is an intrinsic property. Keywords: Electrokinetic energy conversion, Electrochemical flow cell, Conversion efficiency

Piezoelectric energy harvesting from flow-induced vibration

International Nuclear Information System (INIS)

Wang, D-A; Ko, H-H

2010-01-01

A new piezoelectric energy harvester for harnessing energy from flow-induced vibration is developed. It converts flow energy into electrical energy by piezoelectric conversion with oscillation of a piezoelectric film. A finite element model is developed in order to estimate the generated voltage of the piezoelectric laminate subjected to a distributed load. Prototypes of the energy harvester are fabricated and tested. Experimental results show that an open circuit output voltage of 2.2 V pp and an instantaneous output power of 0.2 µW are generated when the excitation pressure oscillates with an amplitude of 1.196 kPa and a frequency of about 26 Hz. The solution of the generated voltage based on the finite element model agrees well with the experiments. Based on the finite element model, the effects of the piezoelectric film dimensions, the fluid pressure applied to the harvester and types of piezoelectric layer on the output voltage of the harvester can be investigated.

Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery.

Science.gov (United States)

Li, Bin; Nie, Zimin; Vijayakumar, M; Li, Guosheng; Liu, Jun; Sprenkle, Vincent; Wang, Wei

2015-02-24

Redox flow batteries are receiving wide attention for electrochemical energy storage due to their unique architecture and advantages, but progress has so far been limited by their low energy density (~25 Wh l(-1)). Here we report a high-energy density aqueous zinc-polyiodide flow battery. Using the highly soluble iodide/triiodide redox couple, a discharge energy density of 167 Wh l(-1) is demonstrated with a near-neutral 5.0 M ZnI2 electrolyte. Nuclear magnetic resonance study and density functional theory-based simulation along with flow test data indicate that the addition of an alcohol (ethanol) induces ligand formation between oxygen on the hydroxyl group and the zinc ions, which expands the stable electrolyte temperature window to from -20 to 50 °C, while ameliorating the zinc dendrite. With the high-energy density and its benign nature free from strong acids and corrosive components, zinc-polyiodide flow battery is a promising candidate for various energy storage applications.

Smart grids, information flows and emerging domestic energy practices

International Nuclear Information System (INIS)

Naus, Joeri; Spaargaren, Gert; Vliet, Bas J.M. van; Horst, Hilje M. van der

2014-01-01

Smart energy grids and smart meters are commonly expected to promote more sustainable ways of living. This paper presents a conceptual framework for analysing the different ways in which smart grid developments shape – and are shaped by – the everyday lives of residents. Drawing upon theories of social practices and the concept of informational governance, the framework discerns three categories of ‘information flows’: flows between household-members, flows between households and energy service providers, and flows between local and distant households. Based on interviews with Dutch stakeholders and observations at workshops we examine, for all three information flows, the changes in domestic energy practices and the social relations they help to create. The analysis reveals that new information flows may not produce more sustainable practices in linear and predictable ways. Instead, changes are contextual and emergent. Second, new possibilities for information sharing between households open up a terrain for new practices. Third, information flows affect social relationships in ways as illustrated by the debates on consumer privacy in the Netherlands. An exclusive focus on privacy, however, deviates attention from opportunities for information disclosure by energy providers, and from the significance of transparency issues in redefining relationships both within and between households. - Highlights: • Smart grids generate three key new information flows that affect social relations. • Practice theory can reveal the ways in which households handle/govern information. • Householders show ambivalence about the workings of the different information flows. • Policies should account for the ‘bright’ as well as the ‘dark’ sides of information

Energy flow analysis during the tennis serve: comparison between injured and noninjured tennis players.

Science.gov (United States)

Martin, Caroline; Bideau, Benoit; Bideau, Nicolas; Nicolas, Guillaume; Delamarche, Paul; Kulpa, Richard

2014-11-01

Energy flow has been hypothesized to be one of the most critical biomechanical concepts related to tennis performance and overuse injuries. However, the relationships among energy flow during the tennis serve, ball velocity, and overuse injuries have not been assessed. To investigate the relationships among the quality and magnitude of energy flow, the ball velocity, and the peaks of upper limb joint kinetics and to compare the energy flow during the serve between injured and noninjured tennis players. Case-control study; Level of evidence, 3. The serves of expert tennis players were recorded with an optoelectronic motion capture system. The forces and torques of the upper limb joints were calculated from the motion captures by use of inverse dynamics. The amount of mechanical energy generated, absorbed, and transferred was determined by use of a joint power analysis. Then the players were followed during 2 seasons to identify upper limb overuse injuries with a questionnaire. Finally, players were classified into 2 groups according to the questionnaire results: injured or noninjured. Ball velocity increased and upper limb joint kinetics decreased with the quality of energy flow from the trunk to the hand + racket segment. Injured players showed a lower quality of energy flow through the upper limb kinetic chain, a lower ball velocity, and higher rates of energy absorbed by the shoulder and elbow compared with noninjured players. The findings of this study imply that improper energy flow during the tennis serve can decrease ball velocity, increase upper limb joint kinetics, and thus increase overuse injuries of the upper limb joints. © 2014 The Author(s).

A flexible energy market - electric power reserves at the place of the end-user

International Nuclear Information System (INIS)

Livik, Klaus; Groenli, Helle; Fretheim, Stig; Feilberg, Nicolai; Gjervan, Sverre; Dymbe, Lars

1996-01-01

If short-term as well as long-term prices in the electric power market are to be stable, then the market must be flexible and both energy and power related efforts must be taken at the end-user's place. The report analyses what type of actors in the electric power market are profiting from a flexible end-user market for energy and power. It is found that a flexible market has utilitarian value for end-users, network owners, suppliers, market operators and system operators. It is also clearly desirable from the point of view of the authorities. Considerable possibilities of developing the flexible energy and power market exist at the end-user. The possibilities can be realized by means of technological developments and political incentives such as by rules for monopoly control. End-user measures may have considerable utilitarian value, socio economically. Especially in areas with high marginal costs of power transport will network owners see the advantages of such measures

Increase of hot initial plasma energy content in the end system of AMBAL-M during hydrogen puffing

International Nuclear Information System (INIS)

Akhmetov, Timour; Bekher, Sergei; Davydenko, Vladimir; Krivenko, Aleksander; Muraviev, Maksim; Reva, Vladimir; Sokolov, Vladimir

2001-01-01

At the end system of the completely axisymmetric mirror trap AMBAL-M the experiments on creation and study of a hot initial plasma have been performed. In the experiments a gas-box was used for hydrogen supply into the hot startup plasma in the mirror trap to increase the plasma density. The hot initial plasma in the trap was produced by the trapping of a plasma stream with developed electrostatic turbulence generated by a gas-discharge source located outside the entrance throat. It was found that in addition to the increase in the plasma density by a factor of 2-3, hydrogen puffing resulted in an unexpected nearly twofold diamagnetism increase. The gas puffing did not reduce the electron temperature in the trap. Essential for explanation of the observed effect is the fact that with the gas puffing the measured plasma potential in the trap increased. The increase in the plasma potential enhanced the trapping of the ion flow entering the trap and increased the average energy of the electron flow entering the trap. It was found that with the increasing hydrogen puffing rate plasma parameters in the trap were saturated. (author)

Triboelectric-based harvesting of gas flow energy and powerless sensing applications

Energy Technology Data Exchange (ETDEWEB)

Taghavi, Majid, E-mail: majid.taghavi@iit.it [Micro-BioRobotics Center, Istituto Italiano di Tecnologia, Pontedera (Italy); Biorobotics Institute, Scuola Superiore Sant’Anna, Pontedera, Pisa (Italy); Sadeghi, Ali; Mazzolai, Barbara [Micro-BioRobotics Center, Istituto Italiano di Tecnologia, Pontedera (Italy); Beccai, Lucia, E-mail: lucia.beccai@iit.it [Micro-BioRobotics Center, Istituto Italiano di Tecnologia, Pontedera (Italy); Mattoli, Virgilio, E-mail: virgilio.mattoli@iit.it [Micro-BioRobotics Center, Istituto Italiano di Tecnologia, Pontedera (Italy)

2014-12-30

Highlights: • The mechanical energy of both pure and impure gases can be harvested by the introduced system. • The blown gas vibrates a non conductive sheet between two surfaces, generating the triboelectric charges. • The system is able to measure the flow rate of the blown gas. • The existence of dust in the blown air can be detected without external powering. • A self powered smoke detector is introduced. - Abstract: In this work, we propose an approach that can convert gas flow energy to electric energy by using the triboelectric effect, in a structure integrating at least two conductive parts (i.e. electrodes) and one non-conductive sheet. The gas flow induces vibration of the cited parts. Therefore, the frequent attaching and releasing between a non-conductive layer with at least one electrode generates electrostatic charges on the surfaces, and then an electron flow between the two electrodes. The effect of blown gas on the output signals is studied to evaluate the gas flow sensing. We also illustrate that the introduced system has an ability to detect micro particles driven by air into the system. Finally we show how we can use this approach for a self sustainable system demonstrating smoke detection and LED lightening.

Triboelectric-based harvesting of gas flow energy and powerless sensing applications

International Nuclear Information System (INIS)

Taghavi, Majid; Sadeghi, Ali; Mazzolai, Barbara; Beccai, Lucia; Mattoli, Virgilio

2014-01-01

Highlights: • The mechanical energy of both pure and impure gases can be harvested by the introduced system. • The blown gas vibrates a non conductive sheet between two surfaces, generating the triboelectric charges. • The system is able to measure the flow rate of the blown gas. • The existence of dust in the blown air can be detected without external powering. • A self powered smoke detector is introduced. - Abstract: In this work, we propose an approach that can convert gas flow energy to electric energy by using the triboelectric effect, in a structure integrating at least two conductive parts (i.e. electrodes) and one non-conductive sheet. The gas flow induces vibration of the cited parts. Therefore, the frequent attaching and releasing between a non-conductive layer with at least one electrode generates electrostatic charges on the surfaces, and then an electron flow between the two electrodes. The effect of blown gas on the output signals is studied to evaluate the gas flow sensing. We also illustrate that the introduced system has an ability to detect micro particles driven by air into the system. Finally we show how we can use this approach for a self sustainable system demonstrating smoke detection and LED lightening

Flow Cells for Scalable Energy Conversion and Storage

Energy Technology Data Exchange (ETDEWEB)

Mukundan, Rangachary [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-10-26

This project is a response to current flow systems that are V-aqueous and not cost effective. It will hopefully enable high energy/ power density flow cells through rational materials and system design.

Analysis of atmospheric flow over a surface protrusion using the turbulence kinetic energy equation with reference to aeronautical operating systems

Science.gov (United States)

Frost, W.; Harper, W. L.

1975-01-01

Flow over surface obstructions can produce significantly large wind shears such that adverse flying conditions can occur for aeronautical systems (helicopters, STOL vehicles, etc.). Atmospheric flow fields resulting from a semi-elliptical surface obstruction in an otherwise horizontally homogeneous statistically stationary flow are modelled with the boundary-layer/Boussinesq-approximation of the governing equation of fluid mechanics. The turbulence kinetic energy equation is used to determine the dissipative effects of turbulent shear on the mean flow. Iso-lines of turbulence kinetic energy and turbulence intensity are plotted in the plane of the flow and highlight regions of high turbulence intensity in the stagnation zone and sharp gradients in intensity along the transition from adverse to favourable pressure gradient. Discussion of the effects of the disturbed wind field in CTOL and STOL aircraft flight path and obstruction clearance standards is given. The results indicate that closer inspection of these presently recommended standards as influenced by wind over irregular terrains is required.

Radiation energy devaluation in diffusion combusting flows of natural gas

International Nuclear Information System (INIS)

Makhanlall, Deodat; Munda, Josiah L.; Jiang, Peixue

2013-01-01

Abstract: CFD (Computational fluid dynamics) is used to evaluate the thermodynamic second-law effects of thermal radiation in turbulent diffusion natural gas flames. Radiative heat transfer processes in gas and at solid walls are identified as important causes of energy devaluation in the combusting flows. The thermodynamic role of thermal radiation cannot be neglected when compared to that of heat conduction and convection, mass diffusion, chemical reactions, and viscous dissipation. An energy devaluation number is also defined, with which the optimum fuel–air equivalence for combusting flows can be determined. The optimum fuel–air equivalence ratio for a natural gas flame is determined to be 0.7. The CFD model is validated against experimental measurements. - Highlights: • Thermodynamic effects of thermal radiation in combusting flows analyzed. • General equation for second-law analyses of combusting flows extended. • Optimum fuel–air equivalence ratio determined for natural gas flame

Improving the performances of H-Darrieus cross-flow turbines through proper detached end plate designs

Science.gov (United States)

Villeneuve, Thierry; Boudreau, Matthieu; Dumas, Guy; CFD Laboratory LMFN Team

2017-11-01

Previous studies on H-Darrieus cross-flow turbines have highlighted the fact that their performances are highly sensitive to the detrimental effects associated with the blades tips. Wingtip devices could be designed in order to attenuate these effects, but the benefits of such devices are always impaired by their added viscous drag since they are moving with the turbine's blades. In this context, the development of fixed and detached end plates, i.e., which are not in contact with the turbine's blades, could reduce the tip losses without the undesirable added drag of typical wingtip devices moving with the blades. The case of a single stationary blade with detached end plates has first been investigated with RANS simulations in order to understand the mechanisms responsible for the increase of the blade's lift. An analysis of the vorticity lines' dynamics provides crucial insights into the effects of the gap width between the blade and the detached end plate on the blade's loading and on the intensity of the tip vortices. Based on these observations, various configurations of detached end plates are tested on cross-flow turbines via RANS and DDES simulations. Preliminary results show that appropriate detached end plates can significantly increase the turbines' efficiency. The authors gratefully acknowledge the Natural Sciences and Engineering Research Council of Canada (NSERC) for their financial support as well as Compute Canada and Calcul Québec for their supercomputer allocations.

The map of energy flow in HVAC systems

International Nuclear Information System (INIS)

Perez-Lombard, Luis; Ortiz, Jose; Maestre, Ismael R.

2011-01-01

Highlights: → Discussion of the four stages in the 'HVAC systems energy chain'. → Examination of HVAC systems as energy conversion devices. → Analysis of HVAC Sankey diagrams. → Discussion of HVAC loads and HVAC energy losses. -- Abstract: Heating, ventilation and air conditioning (HVAC) systems are the most energy consuming building services representing approximately half of the final energy use in the building sector and between one tenth and one fifth of the energy consumption in developed countries. Despite their significant energy use, there is a lack of a consistent and homogeneous framework to efficiently guide research and energy policies, mainly due to the complexity and variety of HVAC systems but also to insufficient rigour in their energy analysis. This paper reviews energy related aspects of HVAC systems with the aim of establishing a common ground for the analysis of their energy efficiency. The paper focuses on the map of energy flow to deliver thermal comfort: the HVAC energy chain. Our approach deals first with thermal comfort as the final service delivered to building occupants. Secondly, conditioned spaces are examined as the systems where useful heat (or coolth) is degraded to provide comfort. This is followed by the analysis of HVAC systems as complex energy conversion devices where energy carriers are transformed into useful heat and coolth, and finally, the impact of HVAC energy consumption on energy resources is discussed.

Study of flow instability in a centrifugal fan based on energy gradient theory

International Nuclear Information System (INIS)

Xiao, Meina; Dou, Hua-Shu; Ma, Xiaoyang; Xiao, Qing; Chen, Yongning; He, Haijiang; Ye, Xinxue

2016-01-01

Flow instability in a centrifugal fan was studied using energy gradient theory. Numerical simulation was performed for the three dimensional turbulent flow field in a centrifugal fan. The flow is governed by the three-dimensional incompressible Navier-Stokes equations coupled with the RNG k-ε turbulent model. The finite volume method was used to discretize the governing equations and the Semiimplicit method for pressure linked equation (SIMPLE) algorithm is employed to iterate the system of the equations. The interior flow field in the centrifugal fan and the distribution of the energy gradient function K are obtained at different flow rates. According to the energy gradient method, the area with larger value of K is the place where the flow loses stability easier. The results show that instability is easier to generate in the regions of impeller outlet and volute tongue. The air flow near the hub is more stable than that near the shroud. That is due to the influences of variations of the velocity and the inlet angle along the axial direction. With the decrease of the flow rate, instability zone in a blade channel moves to the impeller inlet from the outlet and the unstable regions in different channels develop in opposite direction to the rotation of impeller

Redistribution of Kinetic Energy in Turbulent Flows

Directory of Open Access Journals (Sweden)

Alain Pumir

2014-10-01

Full Text Available In statistically homogeneous turbulent flows, pressure forces provide the main mechanism to redistribute kinetic energy among fluid elements, without net contribution to the overall energy budget. This holds true in both two-dimensional (2D and three-dimensional (3D flows, which show fundamentally different physics. As we demonstrate here, pressure forces act on fluid elements very differently in these two cases. We find in numerical simulations that in 3D pressure forces strongly accelerate the fastest fluid elements, and that in 2D this effect is absent. In 3D turbulence, our findings put forward a mechanism for a possibly singular buildup of energy, and thus may shed new light on the smoothness problem of the solution of the Navier-Stokes equation in 3D.

Drag Reduction by Laser-Plasma Energy Addition in Hypersonic Flow

International Nuclear Information System (INIS)

Oliveira, A. C.; Minucci, M. A. S.; Toro, P. G. P.; Chanes, J. B. Jr; Myrabo, L. N.

2008-01-01

An experimental study was conducted to investigate the drag reduction by laser-plasma energy addition in a low density Mach 7 hypersonic flow. The experiments were conducted in a shock tunnel and the optical beam of a high power pulsed CO 2 TEA laser operating with 7 J of energy and 30 MW peak power was focused to generate the plasma upstream of a hemispherical model installed in the tunnel test section. The non-intrusive schlieren optical technique was used to visualize the effects of the energy addition to hypersonic flow, from the plasma generation until the mitigation of the shock wave profile over the model surface. Aside the optical technique, a piezoelectric pressure transducer was used to measure the impact pressure at stagnation point of the hemispherical model and the pressure reduction could be observed

Modeling energy market dynamics using discrete event system simulation

International Nuclear Information System (INIS)

Gutierrez-Alcaraz, G.; Sheble, G.B.

2009-01-01

This paper proposes the use of Discrete Event System Simulation to study the interactions among fuel and electricity markets and consumers, and the decision-making processes of fuel companies (FUELCOs), generation companies (GENCOs), and consumers in a simple artificial energy market. In reality, since markets can reach a stable equilibrium or fail, it is important to observe how they behave in a dynamic framework. We consider a Nash-Cournot model in which marketers are depicted as Nash-Cournot players that determine supply to meet end-use consumption. Detailed engineering considerations such as transportation network flows are omitted, because the focus is upon the selection and use of appropriate market models to provide answers to policy questions. (author)

Energy flow around a moving dislocation

International Nuclear Information System (INIS)

Koizumi, H; Kirchner, H O K

2009-01-01

A dislocation moving in a lattice emits lattice waves. We study the energy flow accompanying the lattice wave emission in a molecular dynamics situation. About two thirds of the static free energy are emitted as lattice waves from the moving dislocation. Work done by the region around the dislocation helps to initiate the motion from the unstable equilibrium state under a small applied stress, or to compensate the energy emitted as lattice waves when the dislocation makes a long distance motion under a larger stress.

Encyclopaedia of energy. Six volume set, 1-6

Energy Technology Data Exchange (ETDEWEB)

Cleveland, C.; Ayres, R.; Costanza, R.; Goldemberg, J. (and others) [Boston University, MA (US). Center for Energy and Environmental Studies

2004-07-01

The Encyclopaedia provides information about all aspects of energy. It is written by leading international authorities (approximately 400 authors). Contents are: Basics of Energy; Energy Flows; Society and Energy; History and Energy; Systems of Energy; Conservation and End Use; Renewable and Alternative Sources; Environmental Issues; Public Issues; Policy Issues; Economics of Energy; Measurement and Models; Material Use and Reuse; Oil and Natural Gas; Coal, Electricity; Nuclear Energy; Risks; Sustainable Development; Global Issues; Appendices.

Energy Division annual progress report for period ending September 30, 1988: Volume 2

Energy Technology Data Exchange (ETDEWEB)

1989-06-01

The goals and accomplishments of the Energy Division of Oak Ridge National Laboratory are described in this annual progress report for Fiscal Year (FY) 1988. The Energy Division is a multidisciplinary research organization committed to (1) increasing the knowledge and understanding of the way society makes choices in energy use and energy-using technologies, (2) improving society's understanding of the environmental implications of changes in energy technology, and (3) improving and developing new energy-efficient technologies. The Energy Division's programmatic activities focus on four major areas: (1) analysis and assessment, (2) transportation and decision systems research, (3) technology research and development for improving the efficiency of energy and end-use technologies, and (4) electric power systems. The Division's total expenditures in FY 1988 were $44.3 million. The work is supported by the US Department of Energy, US Department of Defense, many other federal agencies, and some private organizations. Disciplines of the 139 staff members include engineering, social sciences, physical and life sciences, and mathematics and statistics.

Energy, entropy, and the flow of nature

CERN Document Server

Sherman, Thomas F

2018-01-01

A fresh and unified exploration of the laws that govern natural change, examining the historical roots and meaning of the concepts of energy and entropy. All natural processes--mechanical, thermal, chemical, electrical, and biological--are viewed as a flow across free energy gradients that interact with one another.

Heat transfer and flow in solar energy and bioenergy systems

Science.gov (United States)

Xu, Ben

The demand for clean and environmentally benign energy resources has been a great concern in the last two decades. To alleviate the associated environmental problems, reduction of the use of fossil fuels by developing more cost-effective renewable energy technologies becomes more and more significant. Among various types of renewable energy sources, solar energy and bioenergy take a great proportion. This dissertation focuses on the heat transfer and flow in solar energy and bioenergy systems, specifically for Thermal Energy Storage (TES) systems in Concentrated Solar Power (CSP) plants and open-channel algal culture raceways for biofuel production. The first part of this dissertation is the discussion about mathematical modeling, numerical simulation and experimental investigation of solar TES system. First of all, in order to accurately and efficiently simulate the conjugate heat transfer between Heat Transfer Fluid (HTF) and filler material in four different solid-fluid TES configurations, formulas of an e?ective heat transfer coe?cient were theoretically developed and presented by extending the validity of Lumped Capacitance Method (LCM) to large Biot number, as well as verifications/validations to this simplified model. Secondly, to provide design guidelines for TES system in CSP plant using Phase Change Materials (PCM), a general storage tank volume sizing strategy and an energy storage startup strategy were proposed using the enthalpy-based 1D transient model. Then experimental investigations were conducted to explore a novel thermal storage material. The thermal storage performances were also compared between this novel storage material and concrete at a temperature range from 400 °C to 500 °C. It is recommended to apply this novel thermal storage material to replace concrete at high operating temperatures in sensible heat TES systems. The second part of this dissertation mainly focuses on the numerical and experimental study of an open-channel algae

Biomethane storage: Evaluation of technologies, end uses, business models, and sustainability

International Nuclear Information System (INIS)

Budzianowski, Wojciech M.; Brodacka, Marlena

2017-01-01

Highlights: • Biomethane storage integrates the different energy subsystems. • It facilitates adoption of solar and wind energy sources. • It is essential to adequately match storages with their end uses and business models. • Business models must propose, create, and capture value linked with gas storage. • Sustainable is economically viable, environmentally benign, and socially beneficial. - Abstract: Biomethane is a renewable gas that can be turned into dispatchable resource through applying storage techniques. The storage enables the discharge of stored biomethane at any time and place it is required as gas turbine power, heat or transport fuel. Thus the stored biomethane could more efficiently serve various energy applications in the power, transport, heat, and gas systems as well as in industry. Biomethane storage may therefore integrate the different energy subsystems making the whole energy system more efficient. This work provides an overview and evaluation of biomethane storage technologies, end uses, business models and sustainability. It is shown that storage technologies are versatile, have different costs and efficiencies and may serve different end uses. Business models may be created or selected to fit regional spatial contexts, realistic demands for gas storage related services, and the level of available subsidies. By applying storage the sustainability of biomethane is greatly improved in terms of economic viability, reduced environmental impacts and greater social benefits. Stored biomethane may greatly facilitate adoption of intermittent renewable energy sources such as solar and wind. Other findings show that biomethane storage needs to be combined with grid services and other similar services to reduce overall storage costs.

Petroleum situation at the end of 2004. The US energy policy. Chinese situation and energy policy. Energies: which energy relations between the European Union and its bordering countries

International Nuclear Information System (INIS)

Lamy, J.; Bellet, R.; Lorec, Ph.; Bertin, M.; Avergne, R.

2004-01-01

This issue of Energies et Matieres Premieres newsletter comprises 4 articles dealing with: the petroleum situation at the end of the year 2004 (strong rise of oil prices since the beginning of the year, strained balance between supply and demand at the end of the year, lack of market flexibility in front of an increasing demand, persistence of high prices in relation with low US stocks, high petroleum prices expected for 2005); the US energy situation and policy (growing up disequilibrium between the energy supply and demand, the security of supplies in the center of the US energy policy, R and D actions in the energy domain, towards a mastery of energy demand); the Chinese energy situation and policy (increasing hydrocarbons demand and second world petroleum consumer, increase of gas imports expected for the coming years, strong coal dependence, China is looking for energy self-sufficiency and a better power generation); the foreign energy policy of the European Union with its neighboring countries (50% of energy imports in 2004 and 70% expected for 2030, need for huge trans-European and foreign energy networks, 3 priority area of cooperation (Russia, Euro-Mediterranean area, South-East Europe) and 3 area of common interest (Baltic sea countries, Caspian sea basin, Ukraine), conclusions of the 19. world energy congress (Sydney, Australia, 5-9 september 2004)). A brief summary of the evolution of the world energy indicators (consumption, production, energy bill, prices, sectoral consumption) between January 2002 and October 2004 is presented in the form of graphics at the end of the document. (J.S.)

Material and energy flows in rotary kiln-electric furnace smelting of ferronickel alloy with energy saving

International Nuclear Information System (INIS)

Liu, Peng; Li, Baokuan; Cheung, Sherman C.P.; Wu, Wenyuan

2016-01-01

Highlights: • Establish the synergy relationship of material and energy in key RKEF processes. • Develop an analysis model to study energy saving with internal cycling of energy. • Analyze material and energy flow parameters and assess its associated synergy effect. • A methodology to evaluate the synergy and design indices of RKEF processes. - Abstract: An energy saving strategy with two energy saving measures has been proposed for reducing energy loss in the rotary kiln-electric furnace (RKEF) for the smelting of ferronickel alloy. One of the measures is to recover the waste heat of exhaust gas from the rotary kiln for preheating and dehydrating the wet laterite ores in the rotary dryer. Another measure is to recycle the furnace gas from the electric furnace into the rotary kiln as fuel. Based on the mass conservation and energy conservation laws, an analysis model of material and energy flows has been developed to understand the potential energy saving with the internal cycling of material and energy in the RKEF process. The analysis model not only considers the energy efficiency but also assess the synergy degree of system. Furthermore, the model also predicts the ratio of raw materials and the energy flow distribution to investigate residual heat and energy and analyze the effects of nickel content on energy flow. Finally, the evaluation methodology of synergy and the technic indices are also presented. Through the investigation of the synergy effect, the performance of the RKEF process can be evaluated and quantified for performance optimization in future.

Reynolds number and end-wall effects on a lid-driven cavity flow

International Nuclear Information System (INIS)

Prasad, A.K.; Koseff, J.R.

1989-01-01

A series of experiments has been conducted in a lid-driven cavity of square cross section (depth = width = 150 mm) for Reynolds numbers (Re, based on lid speed and cavity width) between 3200 and 10 000, and spanwise aspect ratios (SAR) between 0.25:1 and 1:1. Flow visualization using polystyrene beads and two-dimensional laser-Doppler anemometer (LDA) measurements have shed new light on the momentum transfer processes within the cavity. This paper focuses on the variation, with Re and SAR, of the mean and the rms velocities profiles, as well as the /similar to/(U'V') profile, along the horizontal and vertical centerlines in the symmetry plane. In addition, the contribution of the large-scale ''organized structures,'' and the high-frequency ''turbulent'' velocity fluctuations to the total rms is examined. At low Re, the organized structures account for most of the energy contained in the flow irrespective of SAR. As the Re increases, however, so does the energy content of the higher frequency fluctuations. This trend is not independent of SAR; a reduction in the SAR causes the ''organized structures'' to again become more evident

Biomass Resource Allocation among Competing End Uses

Energy Technology Data Exchange (ETDEWEB)

Newes, E.; Bush, B.; Inman, D.; Lin, Y.; Mai, T.; Martinez, A.; Mulcahy, D.; Short, W.; Simpkins, T.; Uriarte, C.; Peck, C.

2012-05-01

The Biomass Scenario Model (BSM) is a system dynamics model developed by the U.S. Department of Energy as a tool to better understand the interaction of complex policies and their potential effects on the biofuels industry in the United States. However, it does not currently have the capability to account for allocation of biomass resources among the various end uses, which limits its utilization in analysis of policies that target biomass uses outside the biofuels industry. This report provides a more holistic understanding of the dynamics surrounding the allocation of biomass among uses that include traditional use, wood pellet exports, bio-based products and bioproducts, biopower, and biofuels by (1) highlighting the methods used in existing models' treatments of competition for biomass resources; (2) identifying coverage and gaps in industry data regarding the competing end uses; and (3) exploring options for developing models of biomass allocation that could be integrated with the BSM to actively exchange and incorporate relevant information.

A compact low energy multibeam gamma-ray densitometer for pipe-flow measurements

International Nuclear Information System (INIS)

Tjugum, Stein-Arild; Frieling, Joop; Johansen, Geir Anton

2002-01-01

A compact low-energy multibeam gamma-ray densitometer for oil/water/gas pipe-flow measurement has been built at the University of Bergen. The instrument consists of one Am-241 source and three detectors, all collimated and embedded in the pipe wall. Only the 59.5 keV radiation energy of the source is utilized. Two of the detectors measure transmitted radiation across the pipe flow, and one measure scattered radiation at a 90 degree sign angle. The purpose of the multibeam measurement geometry is to acquire flow regime information and to reduce the flow regime dependency of the gas volume fraction (GVF) measurements. The measurement of scattered radiation enables the dual modality densitometry (DMD) measurement principle to be exploited. Its basic principle is to combine the measurement of scattered and transmitted radiation in order to obtain salinity independent GVF measurements. The salinity dependency is otherwise strongly significant when using low-energy radiation. It is also possible to measure the salinity by using this principle. The instrument is a laboratory prototype, and it has been used for characterising the measurement principle and to test different detector alternatives. The testing of the instrument includes static tests on plastic phantoms, tests on simulated water/gas flow and three phase flow loop tests. Both the multibeam measurement principle and the DMD principle have been verified to provide valuable information. This paper presents the physics behind, experimental results and an evaluation of the system

Experimental study of exhaust noise generated by pulsating flow downstream of pipe end; Myakudoryu ni yori yukisareru kantanbu karyu ni okeru haiki soon no jikkenteki kenkyu

Energy Technology Data Exchange (ETDEWEB)

Higashiyama, J; Iwamoto, J [Tokyo Denki University, Tokyo (Japan)

1997-10-01

A experimental study was carried out for the emissoin of the exhaust noise from an open end of the pipe generated by the pulsating flow in the pipe. The pressure histories along the pipe, the exhaust noise and visualized the flow field downstream of the pipe end were obtained. And a characteristic of frequency for the exhaust noise was examined, using Wigner distribution (WD). A relation between the pulsating flow in the pipe and the exhaust noise was important for understanding the mechanism of the exhaust noise generation. 4 refs., 8 figs., 1 tab.

Radial, sideward and elliptic flow at AGS energies

Indian Academy of Sciences (India)

the sideward flow, the elliptic flow and the radial transverse mass distribution of protons data at. AGS energies. In order to ... data on both sideward and elliptic flow, NL3 model is better at 2 A¡GeV, while NL23 model is at 4–8. A¡GeV. ... port approach RBUU which is based on a coupled set of covariant transport equations for.

Pressure loss coefficient and flow rate of side hole in a lower end plug for dual-cooled annular nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Shin, Chang-Hwan, E-mail: shinch@kaeri.re.kr; Park, Ju-Yong, E-mail: juyong@kaeri.re.kr; In, Wang-Kee, E-mail: wkin@kaeri.re.kr

2013-12-15

Highlights: • A lower end plug with side flow holes is suggested to provide alternative flow paths of the inner channel. • The inlet loss coefficient of the lower end plug is estimated from the experiment. • The flow rate through the side holes is estimated in a complete entrance blockage of inner channel. • The consequence in the reactor core condition is evaluated with a subchannel analysis code. - Abstract: Dual-cooled annular nuclear fuel for a pressurized water reactor (PWR) has been introduced for a significant increase in reactor power. KAERI has been developing a dual-cooled annular fuel for a power uprate of 20% in an optimized PWR in Korea, the OPR1000. This annular fuel can help decrease the fuel temperature substantially relative to conventional cylindrical fuel at a power uprate. Annular fuel has dual flow channels around itself; however, the inner flow channel has a weakness in that it is isolated unlike the outer flow channel, which is open to other neighbouring outer channels for a coolant exchange in the reactor core. If the entrance of the inner channel is, as a hypothetical event, completely blocked by debris, the inner channel will then experience a rapid increase in coolant temperature such that a departure from nucleate boiling (DNB) may occur. Therefore, a remedy to avoid such a postulated accident is indispensable for the safety of annular fuel. A lower end plug with side flow holes was suggested to provide alternative flow paths in addition to the central entrance of the inner channel. In this paper, the inlet loss coefficient of the lower end plug and the flow rate through the side holes were estimated from the experimental results even in a complete entrance blockage of the inner channel. An optimization for the side hole was also performed, and the results are applied to a subchannel analysis to evaluate the consequence in the reactor core condition.

The End of Cheap Oil: Economic, Social, and Political Change in the US and Former Soviet Union

OpenAIRE

Kaufmann, Robert

2014-01-01

I use the quality and quantity of energy flows to interpret economic, social, and political changes in the US and Former Soviet Union. The economic successes of both the former Soviet Union (FSU) and the US reflect an abundant supply of high quality energy. This abundance ended in the 1970s in the US and the 1980s in the Former Soviet Union. In the US, the end of cheap oil caused labor productivity to stagnate, which stopped on-going growth in wages and family incomes. To preserve the Ameri...

Study of flow and loss processes at the ends of a linear theta pinch. Progress report for the period June 1, 1976--May 31, 1977

International Nuclear Information System (INIS)

York, T.M.; Klevans, E.H.

1977-02-01

Experimental and analytical studies initiating and supporting research on flow and energy losses at the ends of a linear theta pinch have been carried out. A 25 cm linear pinch coil has been driven by a 515,000 A discharge with 10 μsec half-cycle time supplied by a 100 μF, 18 kV energy storage system. With reliable preionization generated up to 400 mT He, current sheath behavior has been identified with magnetic loop probes and double loop probes. Spectroscopic determination of preionization has been made. A ruby laser Thomson scattering diagnostic has been designed and is being procured. A study of transient plasma behavior in a 10 cm theta pinch has been carried out with a Twyman-Green interferometer using a 7 mW He--Ne CW laser. Pressure, electric field, and velocity probe diagnostics have received preliminary testing. Design work has been completed for the doubling of pinch length and energy storage system. Studies of particle loss scaling and reactor scaling of linear theta pinch devices have been reported. Detailed calculations of plasma properties at the end of the pinch coil following expansion from the central coil have been carried out. A O--D, time dependent computer code that includes conduction, convection, and magnetic field diffusion has been developed. Predicted plasma behavior is in good agreement with experimental data

Multiple Input Energy Harvesting Systems for Autonomous IoT End-Nodes

Directory of Open Access Journals (Sweden)

Johan J. Estrada-López

2018-03-01

Full Text Available The Internet-of-Things (IoT paradigm is under constant development and is being enabled by the latest research work from both industrial and academic communities. Among the many contributions in such diverse areas as sensor manufacturing, network protocols, and wireless communications, energy harvesting techniques stand out as a key enabling technology for the realization of batteryless IoT end-node systems. In this paper, we give an overview of the recent developments in circuit design for ultra-low power management units (PMUs, focusing mainly in the architectures and techniques required for energy harvesting from multiple heterogeneous sources. The paper starts by discussing a general structure for IoT end-nodes and the main characteristics of PMUs for energy harvesting. Then, an overview is given of different published works for multisource power harvesting, observing their main advantages and disadvantages and comparing their performance. Finally, some open areas of research in multisource harvesting are observed and relevant conclusions are given.

The case study of energy flow analysis and strategy in pulp and paper industry

International Nuclear Information System (INIS)

Chen, Hua-Wei; Hsu, Chung-Hsuan; Hong, Gui-Bing

2012-01-01

The pulp and paper industry is a significant consumer of fossil energy in the Taiwanese manufacturing sector. The concentration of greenhouse gases (GHG) from manufacturing factory activities and vehicle emissions has increased remarkably. Notable energy savings can be achieved in the pulp and paper industry through energy flow analysis. The aim of this paper is to analyze the energy flow for three major energy consuming mills of the pulp and paper industry in Taiwan to make energy savings. In addition, potential technology options are examined for the capture of some of the energy that is currently lost in the processes and to identify the areas of energy saving potential that could have a large impact across more than one industry. The results of this study can serve as a benchmark for developing a quantified list in terms of energy savings potential and opportunities for improving the efficiency of the pulp and paper industry. - Highlights: ► The aim of this paper was to analyze the energy flow for three pulps and paper firms in Taiwan. ► The results were used as the basis for developing a quantified list in terms of energy savings potential. ► Energy flow analysis results can serve as benchmarks for the current pulp and paper making operations.

Energy extraction from ocean currents using straight bladed cross-flow hydrokinetic turbine

Directory of Open Access Journals (Sweden)

Prasad Dudhgaonkar

2017-04-01

Full Text Available Harvesting marine renewable energy remains to be a prime focus of researchers across the globe both in environmental and in commercial perspectives. India is blessed with a long coastline, and the seas around Indian peninsula offer ample potential to tap various ocean energy forms. National Institute of Ocean Technology carries out research and various ocean energy technologies, out of which harnessing kinetic energy in seawater currents is one. This article presents the open sea trials recently carried out on National Institute of Ocean Technology’s cross-flow hydrokinetic ocean current turbine in South Andaman. The turbine was designed to generate 100 W electricity at 1.2 m/s current speed and was built in-house. The turbine was initially tested in a seawater channel and then was deployed in Macpherson Strait in Andaman. It was fitted below a floating platform designed especially for this purpose, and the performance of the turbine was continuously logged inside an on-board data acquisition system. The trials were successful and in line with computations.

Numerical investigations of the unsteady blood flow in the end-to-side arteriovenous fistula for hemodialysis.

Science.gov (United States)

Jodko, Daniel; Obidowski, Damian; Reorowicz, Piotr; Jóźwik, Krzysztof

2016-01-01

The aim of this study was to investigate the blood flow in the end-to-side arteriovenous (a-v) fistula, taking into account its pulsating nature and the patient-specific geometry of blood vessels. Computational Fluid Dynamics (CFD) methods were used for this analysis. DICOM images of the fistula, obtained from the angio-computed tomography, were a source of the data applied to develop a 3D geometrical model of the fistula. The model was meshed, then the ANSYS CFX v. 15.0 code was used to perform simulations of the flow in the vessels under analysis. Mesh independence tests were conducted. The non-Newtonian rheological model of blood and the Shear Stress Transport model of turbulence were employed. Blood vessel walls were assumed to be rigid. Flow patterns, velocity fields, the volume flow rate, the wall shear stress (WSS) propagation on particular blood vessel walls were shown versus time. The maximal value of the blood velocity was identified in the anastomosis - the place where the artery is connected to the vein. The flow rate was calculated for all veins receiving blood. The blood flow in the geometrically complicated a-v fistula was simulated. The values and oscillations of the WSS are the largest in the anastomosis, much lower in the artery and the lowest in the cephalic vein. A strong influence of the mesh on the results concerning the maximal and area-averaged WSS was shown. The relation between simulations of the pulsating and stationary flow under time-averaged flow conditions was presented.

REFCO83, Nuclear Fuel Cycle Cost Economics Using Discounted Cash Flow Analysis

International Nuclear Information System (INIS)

Delene, J.G.; Hermann, O.W.

2001-01-01

1 - Description of program or function: REFCO83 utilizes a discounted cash flow (DCF) analysis procedure to calculate batch, cycle, and lifetime levelized average nuclear fuel cycle costs. The DCF analysis establishes an energy 'cost' associated with the fuel by requiring that the revenues from the sale of energy be adequate to pay the required return on outstanding capital, to pay all expenses including taxes, and to retire the outstanding investment to zero by the end of the economic life of the set of fuel investments. The program uses reactor mass flow information together with individual fuel cost parameters and utility capital structure and money costs to calculate levelized costs cumulatively through any batch or cycle. 2 - Method of solution: A fuel cycle cost component is considered to be any fuel material purchase, processing cost, or discharge material credit in the complete fuel cycle. The costs for each individual component, i.e. uranium, enrichment, etc., may either be expensed or capitalized for tax purposes or, in the case of waste disposal, the cost may also be made proportional to power production. To properly account for the effect of income taxes, all calculations in REFCO83 are done using 'then' current dollars, including price escalations caused by inflation. The database used for the default values for REFCO83 was taken from the Nuclear Energy Cost Data Base. 3 - Restrictions on the complexity of the problem: The maximum number of fuel batches is 120

Momentum-energy transport from turbulence driven by parallel flow shear

International Nuclear Information System (INIS)

Dong, J.Q.; Horton, W.; Bengtson, R.D.; Li, G.X.

1994-04-01

The low frequency E x B turbulence driven by the shear in the mass flow velocity parallel to the magnetic field is studied using the fluid theory in a slab configuration with magnetic shear. Ion temperature gradient effects are taken into account. The eigenfunctions of the linear instability are asymmetric about the mode rational surfaces. Quasilinear Reynolds stress induced by such asymmetric fluctuations produces momentum and energy transport across the magnetic field. Analytic formulas for the parallel and perpendicular Reynolds stress, viscosity and energy transport coefficients are given. Experimental observations of the parallel and poloidal plasma flows on TEXT-U are presented and compared with the theoretical models

Variational energy principle for compressible, baroclinic flow. 2: Free-energy form of Hamilton's principle

Science.gov (United States)

Schmid, L. A.

1977-01-01

The first and second variations are calculated for the irreducible form of Hamilton's Principle that involves the minimum number of dependent variables necessary to describe the kinetmatics and thermodynamics of inviscid, compressible, baroclinic flow in a specified gravitational field. The form of the second variation shows that, in the neighborhood of a stationary point that corresponds to physically stable flow, the action integral is a complex saddle surface in parameter space. There exists a form of Hamilton's Principle for which a direct solution of a flow problem is possible. This second form is related to the first by a Friedrichs transformation of the thermodynamic variables. This introduces an extra dependent variable, but the first and second variations are shown to have direct physical significance, namely they are equal to the free energy of fluctuations about the equilibrium flow that satisfies the equations of motion. If this equilibrium flow is physically stable, and if a very weak second order integral constraint on the correlation between the fluctuations of otherwise independent variables is satisfied, then the second variation of the action integral for this free energy form of Hamilton's Principle is positive-definite, so the action integral is a minimum, and can serve as the basis for a direct trail and error solution. The second order integral constraint states that the unavailable energy must be maximum at equilibrium, i.e. the fluctuations must be so correlated as to produce a second order decrease in the total unavailable energy.

Which cost of debt should be used in forecasting cash flows?

Directory of Open Access Journals (Sweden)

Ignacio Vélez–Pareja

2009-04-01

Full Text Available Frequently, analysts and teachers use the capitalized rate of interest for the cost of debt when forecasting and discounting cash flows. Others estimate the interest payments when forecasting annual financial statements or cash flows based on the average of debt calculated with the beginning and ending balance. Others use the end of year convention that calculates the yearly interest multiplying the beginning balance times its contractual cost. The use of one or other methods is critical for the definition of the tax savings. These approaches are illustrated with examples and the differences in using them. A simple proposal to solve the problem is presented.

Energy fluxes and spectra for turbulent and laminar flows

KAUST Repository

Verma, Mahendra K.; Kumar, Abhishek; Kumar, Praveen; Barman, Satyajit; Chatterjee, Anando G.; Samtaney, Ravi

2017-01-01

spectrum $E(k)$ and energy flux $\\Pi(k)$ using spectral simulations on grids up to $4096^3$, and show consistency between the numerical results and predictions by the aforementioned models. We also construct a model for laminar flows that predicts $E(k

Energy flow characteristics of vector X-Waves

KAUST Repository

Salem, Mohamed; Bagci, Hakan

2011-01-01

The vector form of X-Waves is obtained as a superposition of transverse electric and transverse magnetic polarized field components. It is shown that the signs of all components of the Poynting vector can be locally changed using carefully chosen complex amplitudes of the transverse electric and transverse magnetic polarization components. Negative energy flux density in the longitudinal direction can be observed in a bounded region around the centroid; in this region the local behavior of the wave field is similar to that of wave field with negative energy flow. This peculiar energy flux phenomenon is of essential importance for electromagnetic and optical traps and tweezers, where the location and momenta of microand nanoparticles are manipulated by changing the Poynting vector, and in detection of invisibility cloaks. © 2011 Optical Society of America.

Regulation of Renewable Energy Sources to Optimal Power Flow Solutions Using ADMM: Preprint

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yijian; Hong, Mingyi; Dall' Anese, Emiliano; Dhople, Sairaj; Xu, Zi

2017-03-03

This paper considers power distribution systems featuring renewable energy sources (RESs), and develops a distributed optimization method to steer the RES output powers to solutions of AC optimal power flow (OPF) problems. The design of the proposed method leverages suitable linear approximations of the AC-power flow equations, and is based on the Alternating Direction Method of Multipliers (ADMM). Convergence of the RES-inverter output powers to solutions of the OPF problem is established under suitable conditions on the stepsize as well as mismatches between the commanded setpoints and actual RES output powers. In a broad sense, the methods and results proposed here are also applicable to other distributed optimization problem setups with ADMM and inexact dual updates.

Quantifying the Effect of the Principal-Agent Problem on USResidential Energy Use

Energy Technology Data Exchange (ETDEWEB)

Murtishaw, Scott; Sathaye, Jayant

2006-08-12

The International Energy Agency (IEA) initiated andcoordinated this project to investigate the effects of market failures inthe end-use of energy that may isolate some markets or portions thereoffrom energy price signals in five member countries. Quantifying theamount of energy associated with market failures helps to demonstrate thesignificance of energy efficiency policies beyond price signals. In thisreport we investigate the magnitude of the principal-agent (PA) problemaffecting four of the major energy end uses in the U.S. residentialsector: refrigeration, water heating, space heating, and lighting. Usingdata from the American Housing Survey, we develop a novel approach toclassifying households into a PA matrix for each end use. End use energyvalues differentiated by housing unit type from the Residential EnergyConsumption Survey were used to estimate the final and primary energy useassociated with the PA problem. We find that the 2003 associated siteenergy use from these four end uses totaled over 3,400 trillion Btu,equal to 35 percent of the site energy consumed by the residentialsector.

Continuous Hydrothermal Flow Synthesis of Functional Oxide Nanomaterials Used in Energy Conversion Devices

DEFF Research Database (Denmark)

Xu, Yu

Continuous hydrothermal flow synthesis (CHFS) was used to prepare functional oxide nanoparticles. Materials synthesized include NiO, Y-doped ZrO2, Gd-doped CeO2, LaCrO3 and Ni-substituted CoFe2O4. These types of oxides can be applied in several energy conversion devices, e.g. as active materials...... as materials are continuously produced, and the technology can be scaled-up to an industrial-relevant production capacity. The thesis starts with investigating the most appropriate mixer design for a novel two-stage reactor by computational fluid dynamics modelling. On basis of the modelling results, a two......, dense continuous layers (

Analyzing Residential End-Use Energy Consumption Data to Inform Residential Consumer Decisions and Enable Energy Efficiency Improvements

Science.gov (United States)

Carlson, Derrick R.

While renewable energy is in the process of maturing, energy efficiency improvements may provide an opportunity to reduce energy consumption and consequent greenhouse gas emissions to bridge the gap between current emissions and the reductions necessary to prevent serious effects of climate change and will continue to be an integral part of greenhouse gas emissions policy moving forward. Residential energy is a largely untapped source of energy reductions as consumers, who wish to reduce energy consumption for monetary, environmental, and other reasons, face barriers. One such barrier is a lack of knowledge or understanding of how energy is consumed in a home and how to reduce this consumption effectively through behavioral and technological changes. One way to improve understanding of residential energy consumption is through the creation of a model to predict which appliances and electronics will be present and significantly contribute to the electricity consumption of a home on the basis of various characteristics of that home. The basis of this model is publically available survey data from the Residential Energy Consumption Survey (RECS). By predicting how households are likely to consume energy, homeowners, policy makers, and other stakeholders have access to valuable data that enables reductions in energy consumption in the residential sector. This model can be used to select homes that may be ripe for energy reductions and to predict the appliances that are the basis of these potential reductions. This work suggests that most homes in the U.S. have about eight appliances that are responsible for about 80% of the electricity consumption in that home. Characteristics such as census region, floor space, income, and total electricity consumption affect which appliances are likely to be in a home, however the number of appliances is generally around 8. Generally it takes around 4 appliances to reach the 50% threshold and 12 appliances to reach 90% of electricity

Characteristics Air Flow in Room Chamber Test Refrigerator Household Energy Consumption with Inlet Flow Variation

Science.gov (United States)

Susanto, Edy; Idrus Alhamid, M.; Nasruddin; Budihardjo

2018-03-01

Room Chamber is the most important in making a good Testing Laboratory. In this study, the 2-D modeling conducted to assess the effect placed the inlet on designing a test chamber room energy consumption of household refrigerators. Where the geometry room chamber is rectangular and approaching the enclosure conditions. Inlet varied over the side parallel to the outlet and compared to the inlet where the bottom is made. The purpose of this study was to determine and define the characteristics of the airflow in the room chamber using CFD simulation. CFD method is used to obtain flow characteristics in detail, in the form of vector flow velocity and temperature distribution inside the chamber room. The result found that the position of the inlet parallel to the outlet causes air flow cannot move freely to the side of the floor, even flow of air moves up toward the outlet. While by making the inlet is below, the air can move freely from the bottom up to the side of the chamber room wall as well as to help uniform flow.

Power flow control and damping enhancement of a large wind farm using a superconducting magnetic energy storage unit

DEFF Research Database (Denmark)

Chen, S. S.; Wang, L.; Lee, W. J.

2009-01-01

A novel scheme using a superconducting magnetic energy storage (SMES) unit to perform both power flow control and damping enhancement of a large wind farm (WF) feeding to a utility grid is presented. The studied WF consisting of forty 2 MW wind induction generators (IGs) is simulated...

Deterministic and stochastic algorithms for resolving the flow fields in ducts and networks using energy minimization

Science.gov (United States)

Sochi, Taha

2016-09-01

Several deterministic and stochastic multi-variable global optimization algorithms (Conjugate Gradient, Nelder-Mead, Quasi-Newton and global) are investigated in conjunction with energy minimization principle to resolve the pressure and volumetric flow rate fields in single ducts and networks of interconnected ducts. The algorithms are tested with seven types of fluid: Newtonian, power law, Bingham, Herschel-Bulkley, Ellis, Ree-Eyring and Casson. The results obtained from all those algorithms for all these types of fluid agree very well with the analytically derived solutions as obtained from the traditional methods which are based on the conservation principles and fluid constitutive relations. The results confirm and generalize the findings of our previous investigations that the energy minimization principle is at the heart of the flow dynamics systems. The investigation also enriches the methods of computational fluid dynamics for solving the flow fields in tubes and networks for various types of Newtonian and non-Newtonian fluids.

Absent end diastolic flow of umbilical artery Doppler: pregnancy outcome in 62 cases.

Science.gov (United States)

Poulain, P; Palaric, J C; Milon, J; Betremieux, P; Proudhon, J F; Signorelli, D; Grall, J Y; Giraud, J R

1994-02-01

We retrospectively studied the outcome of pregnancy in 62 cases of absent end diastolic flow (AEDF) of umbilical artery Doppler flow velocity waveform. The history of pregnancies revealed that nearly all were of high risk. Many cases presented cerebral (65%) or uterine (55.5%) Doppler flow abnormalities, or both (38%). We noted 10 fetal deaths and decided 7 pregnancy terminations. Malformation and chromosomal defect rate was 16%. We noted 44 (71%) live-births, a very high rate of cesarean section (86%), prematurity (75%), small for gestational age (39%). Forty-five percent of the neonates had a 1-min Apgar score under 7, which dropped to 27% at 5 min. Neonate mortality rate was 6.9% and the total mortality rate was 34% (21/62). Morbidity was significant (7 cases with severe morbidity, 2 cases with chromosomal abnormality of poor prognosis). We compared different sub-groups with a view to looking for some prenatal factors which predict poor neonatal outcome in case of AEDF.

Eight energy and material flow characteristics of urban ecosystems.

Science.gov (United States)

Bai, Xuemei

2016-11-01

Recent decades have seen an expanding literature exploring urban energy and material flows, loosely branded as urban metabolism analysis. However, this has occurred largely in parallel to the mainstream studies of cities as ecosystems. This paper aims to conceptually bridge these two distinctive fields of research, by (a) identifying the common aspects between them; (b) identifying key characteristics of urban ecosystems that can be derived from energy and material flow analysis, namely energy and material budget and pathways; flow intensity; energy and material efficiency; rate of resource depletion, accumulation and transformation; self-sufficiency or external dependency; intra-system heterogeneity; intersystem and temporal variation; and regulating mechanism and governing capacity. I argue that significant ecological insight can be, or has the potential to be, drawn from the rich and rapidly growing empirical findings of urban metabolism studies to understand the behaviour of cities as human-dominated, complex systems. A closer intellectual linkage and cross pollination between urban metabolism and urban ecosystem studies will advance our scientific understanding and better inform urban policy and management practices.

Environmental impact study due to end use energy technologies; Estudio prospectivo del impacto ambiental debido a tecnologias de uso final de la energia

Energy Technology Data Exchange (ETDEWEB)

Manzini Poli, Fabio

1997-11-01

Two thirds of the internal offer of energy in Mexico is consumed by end use sectors through end use technologies (TUF). Here is presented an integral conceptual frame for the environmental impact evaluation due to end use technologies, then the evolution of the interactions between technology-environment-fuel is analyzed in the long term (year 2025) according to three possible scenarios: business as usual, blocks and sustainable. [Spanish] Dos terceras partes de la oferta interna de energia en Mexico la utilizan los sectores de consumo final mediante tecnologias de uso final energetico. En el presente trabajo se introduce un marco conceptual integral para evaluar los impactos ambientales debidos a la utilizacion de tecnologias de uso final de la energia (TUF), luego se analiza la evolucion de las interacciones entre tecnologia-energetico-ambiente a largo plazo (ano 2025) de acuerdo a tres escenarios posibles: tendencial, bloques y sustentable.

Residential applliance data, assumptions and methodology for end-use forecasting with EPRI-REEPS 2.1

Energy Technology Data Exchange (ETDEWEB)

Hwang, R.J,; Johnson, F.X.; Brown, R.E.; Hanford, J.W.; Kommey, J.G.

1994-05-01

This report details the data, assumptions and methodology for end-use forecasting of appliance energy use in the US residential sector. Our analysis uses the modeling framework provided by the Appliance Model in the Residential End-Use Energy Planning System (REEPS), which was developed by the Electric Power Research Institute. In this modeling framework, appliances include essentially all residential end-uses other than space conditioning end-uses. We have defined a distinct appliance model for each end-use based on a common modeling framework provided in the REEPS software. This report details our development of the following appliance models: refrigerator, freezer, dryer, water heater, clothes washer, dishwasher, lighting, cooking and miscellaneous. Taken together, appliances account for approximately 70% of electricity consumption and 30% of natural gas consumption in the US residential sector. Appliances are thus important to those residential sector policies or programs aimed at improving the efficiency of electricity and natural gas consumption. This report is primarily methodological in nature, taking the reader through the entire process of developing the baseline for residential appliance end-uses. Analysis steps documented in this report include: gathering technology and market data for each appliance end-use and specific technologies within those end-uses, developing cost data for the various technologies, and specifying decision models to forecast future purchase decisions by households. Our implementation of the REEPS 2.1 modeling framework draws on the extensive technology, cost and market data assembled by LBL for the purpose of analyzing federal energy conservation standards. The resulting residential appliance forecasting model offers a flexible and accurate tool for analyzing the effect of policies at the national level.

Energy flow in plate assembles by hierarchical version of finite element method

DEFF Research Database (Denmark)

Wachulec, Marcin; Kirkegaard, Poul Henning

method has been proposed. In this paper a modified hierarchical version of finite element method is used for modelling of energy flow in plate assembles. The formulation includes description of in-plane forces so that planes lying in different planes can be modelled. Two examples considered are: L......The dynamic analysis of structures in medium and high frequencies are usually focused on frequency and spatial averages of energy of components, and not the displacement/velocity fields. This is especially true for structure-borne noise modelling. For the analysis of complicated structures...... the finite element method has been used to study the energy flow. The finite element method proved its usefulness despite the computational expense. Therefore studies have been conducted in order to simplify and reduce the computations required. Among others, the use of hierarchical version of finite element...

End of the nuclear energy era? From Fukushima to the energy policy turnaround; Ende des Atomzeitalters? Von Fukushima in die Energiewende

Energy Technology Data Exchange (ETDEWEB)

Piepenbrink, Johannes (comp.)

2012-07-01

Due to a violent earthquake and the resulting tsunami, a core melt down resulted at the nuclear power plant Fukushima Daiichi in Japan. Thus, at 30th June, 2011, the Federal Government decided to complete the utilization of the nuclear power in Germany. Is this the end of the atomic age? Under this aspect, the booklet under consideration consists of the following nine contributions: (1) Why is the ''energy policy turnaround'' a social question? (Harald Welzer); (2) Tsunami in the living room: Catastrophes facilitated by the media (Joerg R. Bergmann); (3) Learning from the catastrophe (Manfred Buerger); (4) Perspectives of the nuclear power in Europe and globally (Lutz Mez); (5) Outsider or leader? The 'model Germany' and the European energy policy (Severin Fischer); (6) 'Energy policy turnaround': Quo vadis? (Hardo Bruhns); (7) Energy policy turnarounds in Germany: Motifs and impacts for the European electricity market (Hans-Jochen Luhmann); (8) A short story of the German anti-nuclear movement (Joachim Radkau); (9) Popularity of the apocalypse: Reflections on the cultural history of the fear against nuclear accidents since 1945 (Philipp Gassert).

Public Health Benefits of End-Use Electrical Energy Efficiency in California: An Exploratory Study

Energy Technology Data Exchange (ETDEWEB)

McKone, Thomas E.; Lobscheid, A.B.

2006-06-01

This study assesses for California how increasing end-use electrical energy efficiency from installing residential insulation impacts exposures and disease burden from power-plant pollutant emissions. Installation of fiberglass attic insulation in the nearly 3 million electricity-heated homes throughout California is used as a case study. The pollutants nitrous oxides (NO{sub x}), sulfur dioxide (SO{sub 2}), fine particulate matter (PM2.5), benzo(a)pyrene, benzene, and naphthalene are selected for the assessment. Exposure is characterized separately for rural and urban environments using the CalTOX model, which is a key input to the US Environmental Protection Agency (EPA) Tool for the Reduction and Assessment of Chemicals and other environmental Impacts (TRACI). The output of CalTOX provides for urban and rural populations emissions-to-intake factors, which are expressed as an individual intake fraction (iFi). The typical iFi from power plant emissions are on the order of 10{sup -13} (g intake per g emitted) in urban and rural regions. The cumulative (rural and urban) product of emissions, population, and iFi is combined with toxic effects factors to determine human damage factors (HDFs). HDF are expressed as disability adjusted life years (DALYs) per kilogram pollutant emitted. The HDF approach is applied to the insulation case study. Upgrading existing residential insulation to US Department of Energy (DOE) recommended levels eliminates over the assmned 50-year lifetime of the insulation an estimated 1000 DALYs from power-plant emissions per million tonne (Mt) of insulation installed, mostly from the elimination of PM2.5 emissions. In comparison, the estimated burden from the manufacture of this insulation in DALYs per Mt is roughly four orders of magnitude lower than that avoided.

Energy and exergy utilizations of the Jordanian SMEs industries

International Nuclear Information System (INIS)

Al-Ghandoor, A.; Al Salaymeh, M.; Al-Abdallat, Y.; Al-Rawashdeh, M.

2013-01-01

Highlights: ► We analyze the energy and exergy utilizations of the Jordanian SMEs industries. ► We developed an energy balance for the Jordanian SMEs industries. ► The low efficiencies values suggest that many opportunities for better industrial energy utilizations still exist. - Abstract: This study presents detailed analysis of the energy and exergy utilizations of the Jordanian Small-Medium Enterprises (SMEs) by considering the flows of energy and exergy through the main end uses in the Jordanian industrial sector. To achieve this purpose, a survey covering 180 facilities was conducted and energy consumption data was gathered to establish detailed end-use balance for the Jordanian industrial sector. The energy end-use balance provides a starting point to estimate the site and embodied energy and exergy efficiencies. The average site energy and exergy efficiencies of the Jordanian SMEs industries sector are estimated as 78.3% and 37.9% respectively, while the embodied energy and exergy efficiencies are estimated as 58.9% and 21.2% respectively. The low efficiencies values suggest that many opportunities for better industrial energy utilizations still exist.

Energy demand analytics using coupled technological and economic models

Science.gov (United States)

Impacts of a range of policy scenarios on end-use energy demand are examined using a coupling of MARKAL, an energy system model with extensive supply and end-use technological detail, with Inforum LIFT, a large-scale model of the us. economy with inter-industry, government, and c...

Energy Flow Exciting Field-Aligned Current at Substorm Expansion Onset

Science.gov (United States)

Ebihara, Y.; Tanaka, T.

2017-12-01

At substorm expansion onset, upward field-aligned currents (FACs) increase abruptly, and a large amount of electromagnetic energy starts to consume in the polar ionosphere. A question arises as to where the energy comes from. Based on the results obtained by the global magnetohydrodynamics simulation, we present energy flow and energy conversion associated with the upward FACs that manifest the onset. Our simulations show that the cusp/mantle region transmits electromagnetic energy to almost the entire region of the magnetosphere when the interplanetary magnetic field is southward. Integral curve of the Poynting flux shows a spiral moving toward the ionosphere, probably suggesting the pathway of electromagnetic energy from the cusp/mantle dynamo to the ionosphere. The near-Earth reconnection initiates three-dimensional redistribution of the magnetosphere. Flow shear in the near-Earth region results in the generation of the near-Earth dynamo and the onset FACs. The onset FACs are responsible to transport the electromagnetic energy toward the Earth. In the near-Earth region, the electromagnetic energy coming from the cusp/mantle dynamo is converted to the kinetic energy (known as bursty bulk flow) and the thermal energy (associated with high-pressure region in the inner magnetosphere). Then, they are converted to the electromagnetic energy associated with the onset FACs. A part of electromagnetic energy is stored in the lobe region during the growth phase. The release of the stored energy, together with the continuously supplied energy from the cusp/mantle dynamo, contributes to the energy supply to the ionosphere during the expansion phase.

A highly energy-efficient flow-through electro-Fenton process for organic pollutants degradation

International Nuclear Information System (INIS)

Ma, Liang; Zhou, Minghua; Ren, Gengbo; Yang, Weilu; Liang, Liang

2016-01-01

Highlights: • A highly energy-efficient flow-through electro-Fenton reactor was designed. • It had high H 2 O 2 yield and low energy consumption for organic pollutants degradation. • The effect of operational parameters was optimized and possible process mechanism was studied. • The novel system performed wide practicability and potential for organic pollutants degradation. - Abstract: A highly energy-efficient flow-through Electro-Fenton (E-Fenton) reactor for oxidation of methylene blue (MB) from aqueous solution was designed using a perforated DSA as anode and the graphite felt modified by carbon black and polytetrafluoroethylene (PTFE) as cathode for the in situ generation of H 2 O 2 . The modified cathode had a high H 2 O 2 production with low energy consumption, which was characterized by scanning electron microscopy (SEM), nitrogen adsorption-desorption study and contact angle. The flow-through E-Fenton system was compared to the flow-by and regular one, and confirmed to be best on MB removal and TOC degradation. The operational parameters such as current density, pH, Fe 2+ concentration and flow rate were optimized. The MB and TOC removal efficiency of the effluents could keep above 90% and 50%, respectively, and the energy consumption was 23.0 kWh/kgTOC at the current density of 50 mA, pH 3, 0.3 mM Fe 2+ , and the flow rate of 7 mL/min. ·OH was proved to be the main oxidizing species in this system. After 5 times operation, the system, especially cathode, still showed good stability. Five more organic pollutants including orange II (OG), tartrazine, acetylsalicylic acid (ASA), tetracycline (TC) and 2,4-dichlorophen (2,4-DCP) were investigated and the electric energy consumption (EEC) was compared with literatures. All results demonstrated that this flow-through E-Fenton system was energy-efficient and potential for degradation of organic pollutants.

Supplement to the Annual Energy Outlook 1993

International Nuclear Information System (INIS)

1993-01-01

The Supplement to the Annual Energy Outlook 1993 is a companion document to the Energy Information Administration's (EIA) Annual Energy Outlook 1993 (AEO). Supplement tables provide the regional projections underlying the national data and projections in the AEO. The domestic coal, electric power, commercial nuclear power, end-use consumption, and end-use price tables present AEO forecasts at the 10 Federal Region level. World coal tables provide data and projections on international flows of steam coal and metallurgical coal, and the oil and gas tables provide the AEO oil and gas supply forecasts by Oil and Gas Supply Regions and by source of supply. All tables refer to cases presented in the AEO, which provides a range of projections for energy markets through 2010

Informing the Financing of Universal Energy Access: An Assessment of Current Flows

Energy Technology Data Exchange (ETDEWEB)

Bazilian, Morgan; Nussbaumer, Patrick [United Nations Industrial Development Organization, Vienna (Austria); Gualberti, Giorgio [Technical University of Lisbon, Lisbon (Portugal); Haites, Erik [Margaree Consultants Inc., Toronto (Canada); Levi, Michael [Council on Foreign Relations, New York, NY (United States); Siegel, Judy [Energy and Security Group, Reston, VA (United States); Kammen, Daniel [The World Bank, Washington, DC (United States); Fenhann, Joergen [UNEP Risoe Centre, Technical University of Denmark (Denmark)

2011-07-15

Energy poverty is widely recognized as a major obstacle to economic and social development and poverty alleviation. To help inform the design of appropriate and effective policies to reduce energy poverty, we present a brief analysis of the current macro financial flows in the electricity and gas distribution sectors in developing countries. We build on the methodology used to quantify the flows of investment in the climate change area. This methodology relies on national gross fixed capital formation, overseas development assistance, and foreign direct investment. These high-level and aggregated investment figures provide a sense of scale to policy-makers, but are only a small part of the information required to design financial vehicles. In addition, these figures tend to mask numerous variations between sectors and countries, as well as trends and other temporal fluctuations. Nonetheless, for the poorest countries, one can conclude that the current flows are considerably short (at least five times) of what will be required to provide a basic level of access to clean, modern energy services to the 'energy poor'.

Start-To-End Simulations of the Energy Recovery Linac Prototype FEL

CERN Document Server

Gerth, Christopher; Muratori, Bruno; Owen, Hywel; Thompson, Neil R

2004-01-01

Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that serves as a testbed for the study of beam dynamics and accelerator technology important for the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives for the ERLP are the operation of an oscillator infra-red FEL and demonstration of energy recovery from an electron bunch with an energy spread induced by the FEL. In this paper we present start-to-end simulations including the FEL of the ERLP. The beam dynamics in the high-brightness injector, which consists of a DC photocathode gun and a super-conducting booster, have been modelled using the particle tracking code ASTRA. After the main linac, in which the particles are accelerated to 35 MeV, particles have been tracked with the code ELEGANT. The 3D code GENESIS was used to model the FEL interaction with the electron beam. Different modes of operation and their impact on the design of the ERLP are discussed.

Investigation of the Shear Flow Effect and Tip Clearance on a Low Speed Axial Flow Compressor Cascade

Directory of Open Access Journals (Sweden)

Mahesh Varpe

2013-01-01

Full Text Available This paper explores the effect of inlet shear flow on the tip leakage flow in an axial flow compressor cascade. A flow with a high shear rate is generated in the test section of an open circuit cascade wind tunnel by using a combination of screens with a prescribed solidity. It is observed that a stable shear flow of shear rate 1.33 is possible and has a gradual decay rate until 15 times the height of the shear flow generator downstream. The computational results obtained agree well with the available experimental data on the baseline configuration. The detailed numerical analysis shows that the tip clearance improves the blade loading near the tip through the promotion of favorable incidence by the tip leakage flow. The tip clearance shifts the centre of pressure on the blade surface towards the tip. It, however, has no effect on the distribution of end wall loss and deviation angle along the span up to 60% from the hub. In the presence of a shear inflow, the end wall effects are considerable. On the other hand, with a shear inflow, the effects of tip leakage flow are observed to be partly suppressed. The shear flow reduces the tip leakage losses substantially in terms of kinetic energy associated with it.

Energy harvesting by means of flow-induced vibrations on aerospace vehicles

Science.gov (United States)

Li, Daochun; Wu, Yining; Da Ronch, Andrea; Xiang, Jinwu

2016-10-01

This paper reviews the design, implementation, and demonstration of energy harvesting devices that exploit flow-induced vibrations as the main source of energy. Starting with a presentation of various concepts of energy harvesters that are designed to benefit from a general class of flow-induced vibrations, specific attention is then given at those technologies that may offer, today or in the near future, a potential benefit to extend the operational capabilities and to monitor critical parameters of unmanned aerial vehicles. Various phenomena characterized by flow-induced vibrations are discussed, including limit cycle oscillations of plates and wing sections, vortex-induced and galloping oscillations of bluff bodies, vortex-induced vibrations of downstream structures, and atmospheric turbulence and gusts. It was found that linear or linearized modeling approaches are commonly employed to support the design phase of energy harvesters. As a result, highly nonlinear and coupled phenomena that characterize flow-induced vibrations are neglected in the design process. The Authors encourage a shift in the current design paradigm: considering coupled nonlinear phenomena, and adequate modeling tools to support their analysis, from a design limitation to a design opportunity. Special emphasis is placed on identifying designs and implementations applicable to aircraft configurations. Application fields of flow-induced vibrations-based energy harvesters are discussed including power supply for wireless sensor networks and simultaneous energy harvest and control. A large body of work on energy harvesters is included in this review journal. Whereas most of the references claim direct applications to unmanned aerial vehicles, it is apparent that, in most of the cases presented, the working principles and characteristics of the energy harvesters are incompatible with any aerospace applications. Finally, the challenges that hold back the integration of energy harvesting

Air flow optimization for energy efficient blower of biosafety cabinet class II A2

Science.gov (United States)

Ibrahim, M. D.; Mohtar, M. Z.; Alias, A. A.; Wong, L. K.; Yunos, Y. S.; Rahman, M. R. A.; Zulkharnain, A.; Tan, C. S.; Thayan, R.

2017-04-01

An energy efficient Biosafety Cabinet (BSC) has become a big challenge for manufacturers to develop BSC with the highest level of protection. The objective of research is to increase air flow velocity discharge from centrifugal blower. An aerodynamic duct shape inspired by the shape of Peregrine Falcon’s wing during diving flight is added to the end of the centrifugal blower. Investigation of air movement is determined by computational fluid dynamics (CFD) simulation. The results showed that air velocity can be increased by double compared to typical manufactured BSC and no air recirculation. As conclusion, a novel design of aerodynamic duct shape successfully developed and proved that air velocity can be increase naturally with same impeller speed. It can contribute in increasing energy efficiency of the centrifugal blower. It is vital to BSC manufacturer and can be apply to Heating, Air Ventilation and Air Conditioning (HVAC) industries.

Architected squirt-flow materials for energy dissipation

Science.gov (United States)

Cohen, Tal; Kurzeja, Patrick; Bertoldi, Katia

2017-12-01

In the present study we explore material architectures that lead to enhanced dissipation properties by taking advantage of squirt-flow - a local flow mechanism triggered by heterogeneities at the pore level. While squirt-flow is a known dominant source of dissipation and seismic attenuation in fluid saturated geological materials, we study its untapped potential to be incorporated in highly deformable elastic materials with embedded fluid-filled cavities for future engineering applications. An analytical investigation, that isolates the squirt-flow mechanism from other potential dissipation mechanisms and considers an idealized setting, predicts high theoretical levels of dissipation achievable by squirt-flow and establishes a set of guidelines for optimal dissipation design. Particular architectures are then investigated via numerical simulations showing that a careful design of the internal voids can lead to an increase of dissipation levels by an order of magnitude, compared with equivalent homogeneous void distributions. Therefore, we suggest squirt-flow as a promising mechanism to be incorporated in future architected materials to effectively and reversibly dissipate energy.

Washington State Energy Use Profile, 1960--1990

International Nuclear Information System (INIS)

Anderson, M.

1992-07-01

This report is divided into three sections, each with data on energy consumption, prices, and expenditures. The first section presents an overview of statewide energy use trends. The second section presents energy use trends in four basic consuming sectors: residential, commercial, industrial, and transportation. The third section presents energy use trends in specific resource markets: natural gas, petroleum, electricity, coal, and wood. The appendixes contain information about data, sources, and a glossary. Data about Washington's energy resources are reported in two forms: in measures common to the fuel (kWh, barrels, etc.) and in the generic measure British thermal units (Btu). The common measures allow the reader to quickly grasp information in a familiar form. The generic measure allows the reader to compare energy resources. Conversion to Btu occasionally produces counter-intuitive results. For example, in different years, petroleum products have different average energy values, resulting in different conversion factors from barrels to Btu. A large amount of data contained in the Profile has been categorized and presented in a variety of ways. Understanding the meaning of categories is critical to understanding differences between the tables, especially those tables that present similar data. For example, petroleum trends are not the same as transportation trends, though they are similar because transportation is almost entirely dependent on petroleum. In another example, total end-use fuel energy consumption is not the same as total primary energy consumption. End-use fuel consumption does not include energy used for the generation of electricity. Counting both fuel used for electricity generation and electricity itself could result in double counting. Primary fuel consumption, on the other hand, does include energy used for the generation of electricity and is greater than total end-use consumption

A Thermally-Regenerative Ammonia-Based Flow Battery for Electrical Energy Recovery from Waste Heat.

Science.gov (United States)

Zhu, Xiuping; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce

2016-04-21

Large amounts of low-grade waste heat (temperatures energy can be converted to electricity in battery systems. To improve reactor efficiency, a compact, ammonia-based flow battery (AFB) was developed and tested at different solution concentrations, flow rates, cell pairs, and circuit connections. The AFB achieved a maximum power density of 45 W m(-2) (15 kW m(-3) ) and an energy density of 1260 Wh manolyte (-3) , with a thermal energy efficiency of 0.7 % (5 % relative to the Carnot efficiency). The power and energy densities of the AFB were greater than those previously reported for thermoelectrochemical and salinity-gradient technologies, and the voltage or current could be increased using stacked cells. These results demonstrated that an ammonia-based flow battery is a promising technology to convert low-grade thermal energy to electricity. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Energy efficiency enhancement of natural rubber smoking process by flow improvement using a CFD technique

International Nuclear Information System (INIS)

Tekasakul, Perapong; Promtong, Machimontorn

2008-01-01

A non-uniform flow and large temperature variation in a natural rubber smoking-room cause an inefficient use of energy. Flow uniformity and temperature variation can be improved by using a computational fluid dynamics (CFD) simulation. The effects of the size, position and number of gas supply ducts and ventilating lids which were at the inlets and the outlets of the smoking-room were investigated. The optimal rubber smoking-room of size 2.6 m x 6.2 m x 3.6 m contains 154 50 mm-diameter hot gas supply ducts, and four 0.25 x 0.25 m and four 0.25 x 0.20 m ventilating lids. The velocity distribution of this model in the rubber-hanging area was rather uniform. The average monitoring temperature of 54 positions was 62.1 deg. C. This model could reduce the temperature variation by a factor of three from the original room model, i.e., from 15 to 5.5 deg. C. In a further study, the heat input of an appropriate room model was finely adjusted to obtain a suitable temperature (60 deg. C) for the smoking process. It was found that an appropriate heat supply at this temperature is 11 kW. At this rate, the temperature variation is 5.3 deg. C. This improved model should help the rubber smoking cooperatives to achieve at least a 31.25% saving in energy

Energy efficiency enhancement of natural rubber smoking process by flow improvement using a CFD technique

Energy Technology Data Exchange (ETDEWEB)

Tekasakul, Perapong [Energy Technology Research Center and Department of Mechanical Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand)], E-mail: perapong.t@psu.ac.th; Promtong, Machimontorn [Division of Mechanical Engineering, School of Engineering and Resources, Walailak University, Nakhon Si Thammarat 80160 (Thailand)

2008-09-15

A non-uniform flow and large temperature variation in a natural rubber smoking-room cause an inefficient use of energy. Flow uniformity and temperature variation can be improved by using a computational fluid dynamics (CFD) simulation. The effects of the size, position and number of gas supply ducts and ventilating lids which were at the inlets and the outlets of the smoking-room were investigated. The optimal rubber smoking-room of size 2.6 m x 6.2 m x 3.6 m contains 154 50 mm-diameter hot gas supply ducts, and four 0.25 x 0.25 m and four 0.25 x 0.20 m ventilating lids. The velocity distribution of this model in the rubber-hanging area was rather uniform. The average monitoring temperature of 54 positions was 62.1 deg. C. This model could reduce the temperature variation by a factor of three from the original room model, i.e., from 15 to 5.5 deg. C. In a further study, the heat input of an appropriate room model was finely adjusted to obtain a suitable temperature (60 deg. C) for the smoking process. It was found that an appropriate heat supply at this temperature is 11 kW. At this rate, the temperature variation is 5.3 deg. C. This improved model should help the rubber smoking cooperatives to achieve at least a 31.25% saving in energy.

Technical characteristics of the TRISPAL system high-energy end

International Nuclear Information System (INIS)

Meot, F.

1996-04-01

This document presents an overview of the principle design of the high-energy end of the TRISPAL high-intensity LINAC system, with detailed schemes of the different constituent parts and of the beam envelopes. This schemes are presented with the geometric and magnetic parameters of the optical elements. The aim of this document is to allow the cost evaluation of the complete system. (J.S.). 5 refs., 5 figs., 5 tabs., 1 append

Research on Pulsed Jet Flow Control without External Energy in a Blade Cascade

Directory of Open Access Journals (Sweden)

Jie Chen

2017-12-01

Full Text Available To control the flow separation in the compressors, a novel pulsed jet concept without external energy injection is proposed. The new concept designs a slot in the middle of the blade and sets a micro device to switch the slot periodically. Such a structure is expected to generate a pulsed jet by the pressure difference between the pressure side and the suction side of the blade. In order to analyze the interaction between the pulsed jet and unsteady separated flow, our numerical and experimental study is based on a specific cascade (with a flow separation inside and a pulsed jet (one of the unsteady flow control method. The experimental and numerical results both show that when the frequency of pulsed jet is approximate to that of the separation vortex, then the control tends to be more effective. Based on the numerical simulations, the proper orthogonal decomposition (POD is then used to reveal the control mechanism, extracting the different time-space structures from the original field. The results with the aid of POD show that the pulsed jet can redistribute the kinetic energy of each mode, and strengthen or weaken certain modes, particularly, while the steady jet reduces the kinetic energy of high-order modes in whole. Also, pulsed jet with proper parameters can transfer the energy from higher modes to the first flow mode (averaged flow, which is due to the conversion of the spatial vortical structures and the time evolution of the modes.

Transported Low-Temperature Geothermal Energy for Thermal End Uses Final Report

Energy Technology Data Exchange (ETDEWEB)

Yang, Zhiyao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Xiaobing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gluesenkamp, Kyle R [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mehdizadeh Momen, Ayyoub [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Li, Jan-Mou [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-10-01

The use of geothermal energy is an emerging area for improving the nation’s energy resiliency. Conventionally, geothermal energy applications have focused on power generation using high temperature hydrothermal resources or enhanced geothermal systems. However, many low temperature (below 150°C/300°F) geothermal resources are also available but have not been fully utilized. For example, it is estimated that 25 billion barrels of geothermal fluid (mostly water and some dissolved solids) at 176°F to 302°F (80°C to 150°C) is coproduced annually at oil and gas wells in the United States (DOE 2015). The heat contained in coproduced geothermal fluid (also referred as “coproduced water”) is typically wasted because the fluid is reinjected back into the ground without extracting the heat.

Inductive-energy power flow for X-ray sources

Energy Technology Data Exchange (ETDEWEB)

Ware, K D; Filios, P G; Gullickson, R L; Hebert, M P; Rowley, J E; Schneider, R F; Summa, W J [Defense Nuclear Agency, Alexandria, VA (United States); Vitkovski, I M [Logicon RDA, Arlington, VA (United States)

1997-12-31

The Defense Nuclear Agency (DNA) has been developing inductive energy storage (IES) technology for generating intense x-rays from electron beam-target interactions and from plasma radiating sources (PRS). Because of the complex interaction between the commutation of the current from the plasma and the stable dissipation of the energy in the load, DNA has supported several variations of power flow technology. Major variations include: (1) current interruption using a plasma opening switch (POS); (2) continuous current commutation through current-plasma motion against neutral, ionized, or magnetized medium [i.e., dense plasma focus-like (DPF) and plasma flow switch (PFS) technologies]; and, in addition, possible benefits of (3) directly driven complex PRS loads are being investigated. DNA programs include experimental and theoretical modeling and analysis with investigations (1) on Hawk and a Decade module in conjunction with the development of the bremsstrahlung sources (BRS), and (2) on Hawk, ACE-4 and Shiva-Star, as well as cooperative research on GIT-4 and GIT-8, in conjunction with PRS. (author). 1 tab., 12 figs., 17 refs.

Inductive-energy power flow for X-ray sources

International Nuclear Information System (INIS)

Ware, K.D.; Filios, P.G.; Gullickson, R.L.; Hebert, M.P.; Rowley, J.E.; Schneider, R.F.; Summa, W.J.; Vitkovski, I.M.

1996-01-01

The Defense Nuclear Agency (DNA) has been developing inductive energy storage (IES) technology for generating intense x-rays from electron beam-target interactions and from plasma radiating sources (PRS). Because of the complex interaction between the commutation of the current from the plasma and the stable dissipation of the energy in the load, DNA has supported several variations of power flow technology. Major variations include: (1) current interruption using a plasma opening switch (POS); (2) continuous current commutation through current-plasma motion against neutral, ionized, or magnetized medium [i.e., dense plasma focus-like (DPF) and plasma flow switch (PFS) technologies]; and, in addition, possible benefits of (3) directly driven complex PRS loads are being investigated. DNA programs include experimental and theoretical modeling and analysis with investigations (1) on Hawk and a Decade module in conjunction with the development of the bremsstrahlung sources (BRS), and (2) on Hawk, ACE-4 and Shiva-Star, as well as cooperative research on GIT-4 and GIT-8, in conjunction with PRS. (author). 1 tab., 12 figs., 17 refs

Dark Energy Domination In The Virgocentric Flow

Science.gov (United States)

Byrd, Gene; Chernin, A. D.; Karachentsev, I. D.; Teerikorpi, P.; Valtonen, M.; Dolgachev, V. P.; Domozhilova, L. M.

2011-04-01

Dark energy (DE) was first observationally detected at large Gpc distances. If it is a vacuum energy formulated as Einstein's cosmological constant, Λ, DE should also have dynamical effects at much smaller scales. Previously, we found its effects on much smaller Mpc scales in our Local Group (LG) as well as in other nearby groups. We used new HST observations of member 3D distances from the group centers and Doppler shifts. We find each group's gravity dominates a bound central system of galaxies but DE antigravity results in a radial recession increasing with distance from the group center of the outer members. Here we focus on the much larger (but still cosmologically local) Virgo Cluster and systems around it using new observations of velocities and distances. We propose an analytic model whose key parameter is the zero-gravity radius (ZGR) from the cluster center where gravity and DE antigravity balance. DE brings regularity to the Virgocentric flow. Beyond Virgo's 10 Mpc ZGR, the flow curves to approach a linear global Hubble law at larger distances. The Virgo cluster and its outer flow are similar to the Local Group and its local outflow with a scaling factor of about 10; the ZGR for Virgo is 10 times larger than that of the LG. The similarity of the two systems on the scales of 1 to 30 Mpc suggests that a quasi-stationary bound central component and an expanding outflow applies to a wide range of groups and clusters due to small scale action of DE as well as gravity. Chernin, et al 2009 Astronomy and Astrophysics 507, 1271 http://arxiv.org/abs/1006.0066 http://arxiv.org/abs/1006.0555

Reaction mechanism and reaction coordinates from the viewpoint of energy flow

Energy Technology Data Exchange (ETDEWEB)

Li, Wenjin; Ma, Ao, E-mail: aoma@uic.edu [Department of Bioengineering, The University of Illinois at Chicago, 851 South Morgan Street, Chicago, Illinois 60607 (United States)

2016-03-21

Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C{sub 7eq} → C{sub 7ax} transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

Reaction mechanism and reaction coordinates from the viewpoint of energy flow

International Nuclear Information System (INIS)

Li, Wenjin; Ma, Ao

2016-01-01

Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C 7eq → C 7ax transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

Energy flow during disruptions in JET

International Nuclear Information System (INIS)

Paley, J.I.; Andrew, P.; Cowley, S.C.; Fundamenski, W.; Huber, A.

2005-01-01

Disruptions place severe limitations on the materials selected for plasma facing components in fusion devices. In a disruption, the plasma stored thermal and magnetic energy is dissipated leading to predicted power loadings in the current quench of up to 10 MW m -2 in JET. In the thermal quench very high power loads of up to 10 G Wm -2 would be expected if all the power flowed to the steady state strike points, however this is not observed. In this paper the energy balance associated with both events is investigated. The magnetic energy is found to balance well with radiated energy. Circumstantial evidence for limiter interaction during the thermal quench of plasmas in divertor configuration is presented and a possible mechanism for limiter interaction in disruptions resulting from the collapse of an internal transport barrier is discussed

INTERNATIONAL COMPARISON OF RESIDENTIAL ENERGY USE: INDICATORS OF RESIDENTIAL ENERGY USE AND EFFICIENCY PART ONE: THE DATA BASE

Energy Technology Data Exchange (ETDEWEB)

Schipper, L.; Ketoff, A.; Meyers, S.

1981-05-01

This summary report presents information on the end-uses of energy in the residential sector of seven major OECD countries over the period 1960-1978. Much of the information contained herein has never been published before. We present data on energy consumption by energy type and end-use for three to five different years for each country. Each year table is complemented by a set of indicators, which are assembled for the entire 20-year period at the end of each country listing. Finally, a set of key indicators from each country is displayed together in a table, allowing comparison for three periods: early (1960-63), pre-embargo (1970-73), and recent (1975-78). Analysis of these results, smoothing and interpolation of the data, addition of further data, and analytical comparison of in-country and cross-country trends will follow in the next phase of our work.

Multi-geohazards of Ende city area

Directory of Open Access Journals (Sweden)

Igan Supriatman Sutawidjaja

2014-06-01

Full Text Available http://dx.doi.org/10.17014/ijog.vol2no4.20073The Ende City is a steep mountainous area, of which the height of their peaks are above 1500 m asl. It has the limited extent of plain places, without coastal plains. Due to this condition, large parts of the area are vulnerable to mass-movements mainly debris flows, rock-falls and shallow translational and rotational landslides. On the other hand, Flores Island is a segment of the Banda Arc that contains eleven very active volcanoes and numerous inactive volcanic cones. Two of them, Mount Iya and Mount Kelimutu are included to Ende Regency. The northern foot of Mount Iya is only about 1 km away from the southern outskirts of Ende city. But the presence of Mount Meja and Mount Roja as the barrier, and the orientation of the active crater (K2, the highly explosive eruption of Iya Volcano may not directly endanger the city of Ende. Most pyroclastic flows of previous eruptions and other eruptive material emplaced into the sea, but due to a short horizontal distance between Mount Iya and Ende City, the ejected rock fragments can endanger the city of Ende especially its southern parts. A crack has developed around the active crater (K2 of Iya Volcano. It seems that the crack indicates a major weakness within the volcano, which could result in a giant landslide, entering the sea in future eruptions of Iya Volcano. The kinetic energy which is transmitted through the water may probably generate a tsunami. The Ende City also experienced significant damages in the 1992 earthquake. Luckily this city is located on a solid rock instead of alluvial sediments which can potentially undergo liquefaction.  

Axial-flow-induced vibration for a rod supported by translational springs at both ends

International Nuclear Information System (INIS)

Kang, H.S.; Song, K.N.; Kim, H.K.; Yoon, K.H.

2003-01-01

An axial-flow-induced vibration model was proposed for a rod supported by two translational springs at both ends in order to evaluate the sensitivity to spring stiffness on the FIV for a PWR fuel rod. For developing the model, a one-mode approximation was made based on the assumption that the first mode was dominant in vibration behavior of the single span rod. The first natural frequency and mode shape functions for the flow-induced vibration, called the FIV, model were derived by using Lagrange's method. The vibration displacements were calculated by both of the spring-supported rod and the simple-supported (SS) one. As a result, the vibration displacement for the spring-supported (50 kN m -1 ) rod was 15-20% larger than that of the SS rod when the rods are in axial flow of 5-8 m s -1 velocity. The discrepancy between both displacements became much larger as flow velocity increased, and that of the rod having the short span length was larger than that of the rod having the long span length although the displacement value itself of the long span rod was larger than that of the short one. The vibration displacement for the spring-supported rod appeared to decrease with the increase of the spring constant. Since single span beam supported by the two translational springs are focused on in this paper, further study will be needed to reflect more realistic supporting conditions of the PWR fuel rod such as two springs and four dimples and cross or swirling flow caused by the mixing vane of the spacer grid

Linear magnetic motor/generator. [to generate electric energy using magnetic flux for spacecraft power supply

Science.gov (United States)

Studer, P. A. (Inventor)

1982-01-01

A linear magnetic motor/generator is disclosed which uses magnetic flux to provide mechanical motion or electrical energy. The linear magnetic motor/generator includes an axially movable actuator mechanism. A permament magnet mechanism defines a first magnetic flux path which passes through a first end portion of the actuator mechanism. Another permament magnet mechanism defines a second magnetic flux path which passes through a second end portion of the actuator mechanism. A drive coil defines a third magnetic flux path passing through a third central portion of the actuator mechanism. A drive coil selectively adds magnetic flux to and subtracts magnetic flux from magnetic flux flowing in the first and second magnetic flux path.

Control of energy flow in residential buildings; Energieflussregelung in Wohngebaeuden

Energy Technology Data Exchange (ETDEWEB)

Weiss, Martin

2011-07-01

prices are demonstrated. The energy flow controller requires a prediction of the building heat load. The prediction of the heat load is realized by a model predictive algorithm based on a building model. Using an online identification technique the model parameters are determined and tracked during operation. Based on a sensitivity analysis the parameters to be identified are selected dynamically. The methods' robustness against initial parameter errors is demonstrated in simulation. The methods show a significant sensitivity to the starting time of the identification. The model-predictive algorithm achieves a clear increase of prediction accuracy against mean value based prediction methods. (orig.)

Distributed Multi-Commodity Network Flow Algorithm for Energy Optimal Routing in Wireless Sensor Networks.

Directory of Open Access Journals (Sweden)

J. Trdlicka

2010-12-01

Full Text Available This work proposes a distributed algorithm for energy optimal routing in a wireless sensor network. The routing problem is described as a mathematical problem by the minimum-cost multi-commodity network flow problem. Due to the separability of the problem, we use the duality theorem to derive the distributed algorithm. The algorithm computes the energy optimal routing in the network without any central node or knowledge of the whole network structure. Each node only needs to know the flow which is supposed to send or receive and the costs and capacities of the neighboring links. An evaluation of the presented algorithm on benchmarks for the energy optimal data flow routing in sensor networks with up to 100 nodes is presented.

MAXIMUM AIR SUCTION INTO HORIZONTAL OPEN ENDED CYLINDRICAL LOUVERED PIPE

Directory of Open Access Journals (Sweden)

SAMEER RANJAN SAHU

2017-02-01

Full Text Available The main approach behind the present numerical investigation is to estimate the mass flow rate of air sucked into a horizontal open-ended louvered pipe from the surrounding atmosphere. The present numerical investigation has been performed by solving the conservation equations for mass, momentum and energy along with two equation based k-ɛ model for a louvered horizontal cylindrical pipe by finite volume method. It has been found from the numerical investigation that mass suction rate of air into the pipe increases with increase in louvered opening area and the number of nozzles used. Keeping other parameters fixed, for a given mass flow rate there exists an optimum protrusion of nozzle for highest mass suction into the pipe. It was also found from the numerical investigation that increasing the pipe diameter the suction mass flow rate of air was increased.

Design of State-of-the-art Flow Cells for Energy Applications

Energy Technology Data Exchange (ETDEWEB)

Yang, Ping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-01-31

The worldwide energy demand is increasing every day and it necessitates rational and efficient usage of renewable energy. Undoubtedly, utilization of renewable energy can address various environmental challenges. However, all current renewable energy resources (wind, solar, and hydroelectric power) are intermittent and fluctuating in their nature that raises an important question of introducing effective energy storage solutions. Utilization of redox flow cells (RFCs) has recently been recognized as a viable technology for large-scale energy storage and, hence, is well suited for integrating renewable energy and balancing electricity grids. In brief, RFC is an electrochemical storage device where energy is stored in chemical bonds, similar to a battery, but with reactants external to the cell. The state-of-the-art in flow cell technology uses an aqueous acidic electrolyte and simple metal redox couples. Thus, there is an urgent call to develop efficient (high-energy density) and low-cost RFCs to meet the efflorescent energy storage demands. To address the first challenge of achieving high-energy density, we plan to design and further modify complexes composed of bifunctional multidentate ligands and specific metal centers, capable of storing as many electrons as possible. In order to address the second challenge of reducing cost of the RFCs, we plan to use iron (Fe) metal as it regularly occupies multiple oxidation states and is the second most abundant metal in the earth’s crust that makes it an ideal metal for improved energy densities, higher potentials, and numbers of electrons per molecule while maintaining potential cost competitiveness. Density functional theory calculations considering solvation effects will be performed to yield accurate predictions of redox potentials.

Isospin effects on pt-differential flow in heavy ion collisions at intermediate energies

International Nuclear Information System (INIS)

Bansal, Rubina; Jain, Anupriya; Kumar, Suneel

2014-01-01

This paper aims to study the role of isospin degree of freedom in heavy-ion collisions through the transverse momentum (p t ), neutron to proton ratio and system mass dependence of p t -differential transverse flow. Our study shows that (p t )-differential transverse flow dependence can act as sensitive probe to study symmetry energy and its density dependence compared to the energy of vanishing flow. Symmetry energy and its density dependence play a dominant role over the isospin-dependence of nucleon–nucleon cross-section at Fermi energy. (author)

Studying the collision energy dependence of elliptic and triangular flow with a hybrid model

Energy Technology Data Exchange (ETDEWEB)

Auvinen, Jussi [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Petersen, Hannah [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Institut fuer Theoretische Physik, Goethe Universitaet, Frankfurt am Main (Germany)

2014-07-01

Elliptic flow has been one of the key observables for establishing the finding of the quark-gluon plasma (QGP) at the highest energies of Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). As a sign of collectively behaving matter, the elliptic flow is expected to decrease at lower beam energies, where the QGP is not produced. However, in the recent RHIC beam energy scan, it has been found that the inclusive charged hadron elliptic flow changes relatively little in magnitude within the energy range 7.7-39 GeV per nucleon-nucleon collision. We study the collision energy dependence of the elliptic and triangular flow utilizing a Boltzmann+hydrodynamics hybrid model. Such a hybrid model provides a natural framework for the transition from high collision energies, where the hydrodynamical description is essential, to smaller energies, where the hadron transport dominates. This approach is thus suitable for investigating the relative importance of these two mechanisms for the production of the collective flow at different beam energies.

Lithium-Based High Energy Density Flow Batteries

Science.gov (United States)

Bugga, Ratnakumar V. (Inventor); West, William C. (Inventor); Kindler, Andrew (Inventor); Smart, Marshall C. (Inventor)

2014-01-01

Systems and methods in accordance with embodiments of the invention implement a lithium-based high energy density flow battery. In one embodiment, a lithium-based high energy density flow battery includes a first anodic conductive solution that includes a lithium polyaromatic hydrocarbon complex dissolved in a solvent, a second cathodic conductive solution that includes a cathodic complex dissolved in a solvent, a solid lithium ion conductor disposed so as to separate the first solution from the second solution, such that the first conductive solution, the second conductive solution, and the solid lithium ionic conductor define a circuit, where when the circuit is closed, lithium from the lithium polyaromatic hydrocarbon complex in the first conductive solution dissociates from the lithium polyaromatic hydrocarbon complex, migrates through the solid lithium ionic conductor, and associates with the cathodic complex of the second conductive solution, and a current is generated.

Energy and materials flows in the fabrication of iron and steel semifinished products

Energy Technology Data Exchange (ETDEWEB)

Darby, J.B. Jr.; Arons, R.M.

1979-08-01

The flow of energy and materials in the fabrication of iron and steel semifinished products from molten metal is discussed. The focus is on techniques to reduce the amount of energy required to produce the typical products of integrated steel plants and iron and steel foundries. In integrated steel plants, if only 50% of the steel being cast were continuously cast, industry-wide energy consumption would be reduced by 6 to 15%. Further major energy savings could be achieved by increased use of by-product gases and regenerators in the various reheat operations. Finally, systems optimization studies to maintain the even flow of materials at full capacity should yield further improvements in energy efficiency. In foundry operations, alternate heating methods in forging operations and the use of no-bake molding and core materials should result in substantial energy savings. Studies of specific operations will suggest housekeeping changes to minimize wasted energy. These changes might include fixing heat leaks, reducing floor space requirements, improving temperature regulation, lowering working temperatures in some steel-forming operations, redesigning products, and minimizing scrap generation. There is also a need for new, energy conserving technologies. A good example would be the development of nondestructive testing to determine the existence, location, and size of defects in ingots at elevated temperatures. A second example is the need to reduce, through system studies, the large amount of scrap typical of foundry operations. Finally, computer control of steel mill operations (materials flow, furnace residence times, excessive heating or overheating, and full capacity utilization of all facilities at all times) deserves further study.

The Design and Evaluation of a Front-End User Interface for Energy Researchers.

Science.gov (United States)

Borgman, Christine L.; And Others

1989-01-01

Reports on the Online Access to Knowledge (OAK) Project, which developed software to support end user access to a Department of Energy database based on the skill levels and needs of energy researchers. The discussion covers issues in development, evaluation, and the study of user behavior in designing an interface tailored to a special…

Identification of dominant structures and their flow dynamics in the turbulent two-phase flow using POD technique

Energy Technology Data Exchange (ETDEWEB)

Munir, Shahzad; Siddiqui, Muhammad Israr; Heikal, Morgan; Aziz, Abdul Rashid Abdul [Universiti Teknologi PETRONAS, Bander Seri Iskandar (Malaysia); Sercey, Guillaume de [University of Brighton, Brighton (United Kingdom)

2015-11-15

The Proper orthogonal decomposition (POD) method has seen increasingly used in the last two decades and has a lot of applications for the comparison of experimental and numerically simulated data. The POD technique is often used to extract information about coherent structures dominating the flow. The two-dimensional and two-component instantaneous velocity fields of both liquid and gas phases of a slug flow were obtained by Particle image velocimetry (PIV) combined with Laser induced fluorescence (LIF). POD was applied to the velocity fields of both phases separately to identify the coherent flow structures. We focused on POD eigenmodes and their corresponding energy contents of both liquid and gas phases. The sum of first few eigenmodes that contain maximum turbulent kinetic energy of the flow represents the coherent structures. In the case of liquid phase the first eigenmode contained 42% of the total energy, while in the gas phase the decaying energy distribution was flat. The POD results showed that the coefficient of mode 1 for the liquid phase oscillated between positive and negative values and had the highest amplitude. For the visualization of coherent motion different linear combinations of eigenmodes for liquid and gas phases were used. The phenomena of turbulent bursting events associated with Q2 events (low momentum fluid moving away from the wall) and Q4 events (high momentum flow moving towards the wall) were also discussed to assess its contribution in turbulence production.

Pulsatile blood flow, shear force, energy dissipation and Murray's Law

Directory of Open Access Journals (Sweden)

Bengtsson Hans-Uno

2006-08-01

Full Text Available Abstract Background Murray's Law states that, when a parent blood vessel branches into daughter vessels, the cube of the radius of the parent vessel is equal to the sum of the cubes of the radii of daughter blood vessels. Murray derived this law by defining a cost function that is the sum of the energy cost of the blood in a vessel and the energy cost of pumping blood through the vessel. The cost is minimized when vessel radii are consistent with Murray's Law. This law has also been derived from the hypothesis that the shear force of moving blood on the inner walls of vessels is constant throughout the vascular system. However, this derivation, like Murray's earlier derivation, is based on the assumption of constant blood flow. Methods To determine the implications of the constant shear force hypothesis and to extend Murray's energy cost minimization to the pulsatile arterial system, a model of pulsatile flow in an elastic tube is analyzed. A new and exact solution for flow velocity, blood flow rate and shear force is derived. Results For medium and small arteries with pulsatile flow, Murray's energy minimization leads to Murray's Law. Furthermore, the hypothesis that the maximum shear force during the cycle of pulsatile flow is constant throughout the arterial system implies that Murray's Law is approximately true. The approximation is good for all but the largest vessels (aorta and its major branches of the arterial system. Conclusion A cellular mechanism that senses shear force at the inner wall of a blood vessel and triggers remodeling that increases the circumference of the wall when a shear force threshold is exceeded would result in the observed scaling of vessel radii described by Murray's Law.

Power flow as a complement to statistical energy analysis and finite element analysis

Science.gov (United States)

Cuschieri, J. M.

1987-01-01

Present methods of analysis of the structural response and the structure-borne transmission of vibrational energy use either finite element (FE) techniques or statistical energy analysis (SEA) methods. The FE methods are a very useful tool at low frequencies where the number of resonances involved in the analysis is rather small. On the other hand SEA methods can predict with acceptable accuracy the response and energy transmission between coupled structures at relatively high frequencies where the structural modal density is high and a statistical approach is the appropriate solution. In the mid-frequency range, a relatively large number of resonances exist which make finite element method too costly. On the other hand SEA methods can only predict an average level form. In this mid-frequency range a possible alternative is to use power flow techniques, where the input and flow of vibrational energy to excited and coupled structural components can be expressed in terms of input and transfer mobilities. This power flow technique can be extended from low to high frequencies and this can be integrated with established FE models at low frequencies and SEA models at high frequencies to form a verification of the method. This method of structural analysis using power flo and mobility methods, and its integration with SEA and FE analysis is applied to the case of two thin beams joined together at right angles.

End use technology choice in the National Energy Modeling System (NEMS): An analysis of the residential and commercial building sectors

International Nuclear Information System (INIS)

Wilkerson, Jordan T.; Cullenward, Danny; Davidian, Danielle; Weyant, John P.

2013-01-01

The National Energy Modeling System (NEMS) is arguably the most influential energy model in the United States. The U.S. Energy Information Administration uses NEMS to generate the federal government's annual long-term forecast of national energy consumption and to evaluate prospective federal energy policies. NEMS is considered such a standard tool that other models are calibrated to its forecasts, in both government and academic practice. As a result, NEMS has a significant influence over expert opinions of plausible energy futures. NEMS is a massively detailed model whose inner workings, despite its prominence, receive relatively scant critical attention. This paper analyzes how NEMS projects energy demand in the residential and commercial sectors. In particular, we focus on the role of consumers' preferences and financial constraints, investigating how consumers choose appliances and other end-use technologies. We identify conceptual issues in the approach the model takes to the same question across both sectors. Running the model with a range of consumer preferences, we estimate the extent to which this issue impacts projected consumption relative to the baseline model forecast for final energy demand in the year 2035. In the residential sector, the impact ranges from a decrease of 0.73 quads (− 6.0%) to an increase of 0.24 quads (+ 2.0%). In the commercial sector, the impact ranges from a decrease of 1.0 quads (− 9.0%) to an increase of 0.99 quads (+ 9.0%). - Highlights: • This paper examines the impact of consumer preferences on final energy in the Commercial and Residential sectors of the National Energy Modeling System (NEMS). • We describe the conceptual and empirical basis for modeling consumer technology choice in NEMS. • We offer a range of alternative parameters to show the energy demand sensitivity to technology choice. • We show there are significant potential savings available in both building sectors. • Because the model uses its own

End-Use Opportunity Analysis from Progress Indicator Results for ASHRAE Standard 90.1-2013

Energy Technology Data Exchange (ETDEWEB)

Hart, Philip R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xie, YuLong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-12-01

This report and an accompanying spreadsheet (PNNL 2014a) compile the end use building simulation results for prototype buildings throughout the United States. The results represent he energy use of each edition of ASHRAE Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings (ASHRAE 2004, 2007, 2010, 2013). PNNL examined the simulation results to determine how the remaining energy was used.

Comparison of energy flows in deep inelastic scattering events with and without a large rapidity gap

International Nuclear Information System (INIS)

Derrick, M.; Krakauer, D.; Magill, S.

1994-07-01

Energy flows in deep inelastic electron-proton scattering are investigated at a centre-of-mass energy of 296 GeV for the range Q 2 ≥10 GeV 2 using the ZEUS detector. A comparison is made between events with and without a large rapidity gap between the hadronic system and the proton direction. The energy flows, corrected for detector acceptance and resolution, are shown for these two classes of events in both the HERA laboratory frame and the Breit frame. From the differences in the shapes of these energy flows we conclude that QCD radiation is suppressed in the large-rapidity-gap events compared to the events without a large rapidity gap. (orig.)

Kinetic energy budget for electroconvective flows near ion selective membranes

Science.gov (United States)

Wang, Karen; Mani, Ali

2017-11-01

Electroconvection occurs when ions are driven from a bulk fluid through an ion-selective surface. When the driving voltage is beyond a threshold, this process undergoes a hydrodynamic instability called electroconvection, which can become chaotic due to nonlinear coupling between ion-transport, fluid flow, and electrostatic forces. Electroconvection significantly enhances ion transport and plays an important role in a wide range of electrochemical applications. We investigate this phenomenon by considering a canonical geometry consisting of a symmetric binary electrolyte between an ion-selective membrane and a reservoir using 2D direct numerical simulation (DNS). Our simulations reveal that for most practical regimes, DNS of electroconvection is expensive. Thus, a plan towards development of reduced-order models is necessary to facilitate the adoption of analysis of this phenomenon in industry. Here we use DNS to analyze the kinetic energy budget to shed light into the mechanisms sustaining flow and mixing in electroconvective flows. Our analysis reveals the relative dominance of kinetic energy sources, dissipation, and transport mechanisms sustaining electroconvection at different distances from the interface and over a wide range of input parameters. Karen Wang was supported by the National Defense Science & Engineering Graduate Fellowship (NDSEG). Ali Mani was supported by the National Science Foundation Award.

Power flow control strategy in distribution network for dc type distributed energy resource at load bus

International Nuclear Information System (INIS)

Hanif, A.; Choudhry, M.A.

2013-01-01

This research work presents a feed forward power flow control strategy in the secondary distribution network working in parallel with a DC type distributed energy resource (DER) unit with SPWM-IGBT Voltage Source Converter (VSC). The developed control strategy enables the VSC to be used as power flow controller at the load bus in the presence of utility supply. Due to the investigated control strategy, power flow control from distributed energy resource (DER) to common load bus is such that power flows to the load without facing any power quality problem. The technique has an added advantage of controlling power flow without having a dedicated power flow controller. The SPWM-IGBT VSC is serving the purpose of dc-ac converter as well as power flow controller. Simulations for a test system using proposed power flow control strategy are carried out using SimPower Systems toolbox of MATLAB at the rate and Simulink at the rate. The results show that a reliable, effective and efficient operation of DC type DER unit in coordination with main utility network can be achieved. (author)

Influence of the nuclear symmetry energy on the collective flows of charged pions

Science.gov (United States)

Gao, Yuan; Yong, Gao-Chan; Zhang, Lei; Zuo, Wei

2018-01-01

Based on the isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, we studied charged pion transverse and elliptic flows in semicentral 197Au+197Au collisions at 600 MeV/nucleon. It is found that π+-π- differential transverse flow and the difference of π+ and π- transverse flows almost show no effects of the symmetry energy. Their corresponding elliptic flows are largely affected by the symmetry energy, especially at high transverse momenta. The isospin-dependent pion elliptic flow at high transverse momenta thus provides a promising way to probe the high-density behavior of the symmetry energy in heavy-ion collisions at the Facility for Antiproton and Ion Research (FAIR) at GSI, Darmstadt or at the Cooling Storage Ring (CSR) at HIRFL, Lanzhou.

One-dimensional model of steady, compressible channel flow with mass, momentum, and energy addition

International Nuclear Information System (INIS)

Johnston, S.C.

1976-09-01

A one-dimensional model of steady, compressible channel flow with mass, momentum and energy addition is discussed. An exact solution to the governing equations was found and from it a similarity parameter relating dimensionless mass, momentum and energy addition identified. This similarity parameter is used to make two flows having different dimensionless mass, momentum and energy additions equivalent. Application of the similarity parameter to the LASL Intense Neutron Source experiment and the Sandia simulation of that experiment results in an expression relating the dimensionless mass addition of combustible gas required in the Sandia experiment to dimensionless energy addition in the LASL experiment. Results of the analysis indicate that the Sandia experiment can realistically simulate the energy addition in the LASL Intense Neutron Source experiment

A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

Energy Technology Data Exchange (ETDEWEB)

Joan B. Blainey; Claudia C. Faunt, and Mary C. Hill

2006-05-16

This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.

Triton-3He relative and differential flows as probes of the nuclear symmetry energy at supra-saturation densities

International Nuclear Information System (INIS)

Yong Gaochan; Li Baoan; Chen Liewen; Zhang Xunchao

2009-01-01

Using a transport model coupled with a phase-space coalescence afterburner, we study the triton- 3 He (t- 3 He) ratio with both relative and differential transverse flows in semicentral 132 Sn+ 124 Sn reactions at a beam energy of 400 MeV/nucleon. The neutron-proton ratios with relative and differential flows are also discussed as a reference. We find that similar to the neutron-proton pairs, the t- 3 He pairs also carry interesting information regarding the density dependence of the nuclear symmetry energy. Moreover, the nuclear symmetry energy affects more strongly the t- 3 He relative and differential flows than the π - /π + ratio in the same reaction. The t- 3 He relative flow can be used as a particularly powerful probe of the high-density behavior of the nuclear symmetry energy.

Flexible End2End Workflow Automation of Hit-Discovery Research.

Science.gov (United States)

Holzmüller-Laue, Silke; Göde, Bernd; Thurow, Kerstin

2014-08-01

The article considers a new approach of more complex laboratory automation at the workflow layer. The authors purpose the automation of end2end workflows. The combination of all relevant subprocesses-whether automated or manually performed, independently, and in which organizational unit-results in end2end processes that include all result dependencies. The end2end approach focuses on not only the classical experiments in synthesis or screening, but also on auxiliary processes such as the production and storage of chemicals, cell culturing, and maintenance as well as preparatory activities and analyses of experiments. Furthermore, the connection of control flow and data flow in the same process model leads to reducing of effort of the data transfer between the involved systems, including the necessary data transformations. This end2end laboratory automation can be realized effectively with the modern methods of business process management (BPM). This approach is based on a new standardization of the process-modeling notation Business Process Model and Notation 2.0. In drug discovery, several scientific disciplines act together with manifold modern methods, technologies, and a wide range of automated instruments for the discovery and design of target-based drugs. The article discusses the novel BPM-based automation concept with an implemented example of a high-throughput screening of previously synthesized compound libraries. © 2014 Society for Laboratory Automation and Screening.

SGS Modeling of the Internal Energy Equation in LES of Supersonic Channel Flow

Science.gov (United States)

Raghunath, Sriram; Brereton, Giles

2011-11-01

DNS of fully-developed turbulent supersonic channel flows (Reτ = 190) at up to Mach 3 indicate that the turbulent heat fluxes depend only weakly on Mach number, while the viscous dissipation and pressure dilatation do so strongly. Moreover, pressure dilatation makes a significant contribution to the internal energy budget at Mach 3 and higher. The balance between these terms is critical to determining the temperature (and so molecular viscosity) from the internal energy equation and so, in LES of these flows, it is essential to use accurate SGS models for the viscous dissipation and the pressure dilatation. In this talk, we present LES results for supersonic channel flow, using SGS models for these terms that are based on the resolved-scale dilatation, an inverse timescale, and SGS momentum fluxes, which intrinsically represent this Mach number effect.

Study of hadronization using energy flow from e+e- annihilation into quarks and gluons at √s of 29 GeV

International Nuclear Information System (INIS)

Rosenberg, L.J.

1985-11-01

We have made a high statistics study of QCD jets produced in e + e - annihilations at √s of 29 GeV and observed in the MAC detector located at the PEP storage ring at SLAC. The MAC detector uses calorimetry and provides a homogeneous response over much of its 98% . 4π sr instrumented solid angle. A data sample of well reconstructed hadronic events was selected by requiring that E/sub vis/ in the calorimeters be near √s, and almost all the energy be deposited in the central calorimeters. Fits of the jet transverse energy flow are made to the data using String (STR) model and several types of Independent Jet (IJM) model hypotheses, where α/sub s/, the strong coupling constant, and sigma/sub q/, the width of the secondary quark P/sub perpendicular/ distribution, are free parameters. The fits to O(α/sub s/ 2 using MS-bar renormalization yield α/sub s/ approx.0.17 with the STR hypothesis, and α/sub s/ approx.0.12 with the various IJM hypotheses. The correlations between α/sub s/ and sigma/sub q/ are examined. Detailed comparisons were made with other experimental results. The energy flow projected onto the event plane of 3-jet events selected from the above data sample was studied. The data shows an asymmetric energy flow around the thin jet. Such an asymmetry was predicted by the STR model, and a cluster model (Webber) incorporating soft gluon interference. The various IJM models show no such asymmetry. We associate this asymmetry with coherence effects during hadronization. 106 refs., 58 figs., 18 tabs

Tidal current energy potential of Nalón river estuary assessment using a high precision flow model

Science.gov (United States)

Badano, Nicolás; Valdés, Rodolfo Espina; Álvarez, Eduardo Álvarez

2018-05-01

Obtaining energy from tide currents in onshore locations is of great interest due to the proximity to the points of consumption. This opens the door to the feasibility of new installations based on hydrokinetic microturbines even in zones of moderate speed. In this context, the accuracy of energy predictions based on hydrodynamic models is of paramount importance. This research presents a high precision methodology based on a multidimensional hydrodynamic model that is used to study the energetic potential in estuaries. Moreover, it is able to estimate the flow variations caused by microturbine installations. The paper also shows the results obtained from the application of the methodology in a study of the Nalón river mouth (Asturias, Spain).

High-energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane.

Science.gov (United States)

Jia, Chuankun; Pan, Feng; Zhu, Yun Guang; Huang, Qizhao; Lu, Li; Wang, Qing

2015-11-01

Redox flow batteries (RFBs) are considered one of the most promising large-scale energy storage technologies. However, conventional RFBs suffer from low energy density due to the low solubility of the active materials in electrolyte. On the basis of the redox targeting reactions of battery materials, the redox flow lithium battery (RFLB) demonstrated in this report presents a disruptive approach to drastically enhancing the energy density of flow batteries. With LiFePO4 and TiO2 as the cathodic and anodic Li storage materials, respectively, the tank energy density of RFLB could reach ~500 watt-hours per liter (50% porosity), which is 10 times higher than that of a vanadium redox flow battery. The cell exhibits good electrochemical performance under a prolonged cycling test. Our prototype RFLB full cell paves the way toward the development of a new generation of flow batteries for large-scale energy storage.

High–energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane

Science.gov (United States)

Jia, Chuankun; Pan, Feng; Zhu, Yun Guang; Huang, Qizhao; Lu, Li; Wang, Qing

2015-01-01

Redox flow batteries (RFBs) are considered one of the most promising large-scale energy storage technologies. However, conventional RFBs suffer from low energy density due to the low solubility of the active materials in electrolyte. On the basis of the redox targeting reactions of battery materials, the redox flow lithium battery (RFLB) demonstrated in this report presents a disruptive approach to drastically enhancing the energy density of flow batteries. With LiFePO4 and TiO2 as the cathodic and anodic Li storage materials, respectively, the tank energy density of RFLB could reach ~500 watt-hours per liter (50% porosity), which is 10 times higher than that of a vanadium redox flow battery. The cell exhibits good electrochemical performance under a prolonged cycling test. Our prototype RFLB full cell paves the way toward the development of a new generation of flow batteries for large-scale energy storage. PMID:26702440

Piezoelectric Energy Harvesting in Internal Fluid Flow

Directory of Open Access Journals (Sweden)

Hyeong Jae Lee

2015-10-01

Full Text Available We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA showed fatigue failure was imminent due to stress concentrations near the bimorph’s clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well.

Piezoelectric energy harvesting in internal fluid flow.

Science.gov (United States)

Lee, Hyeong Jae; Sherrit, Stewart; Tosi, Luis Phillipe; Walkemeyer, Phillip; Colonius, Tim

2015-10-14

We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA) showed fatigue failure was imminent due to stress concentrations near the bimorph's clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well.

Energy use in Denmark

International Nuclear Information System (INIS)

Schipper, L.; Howarth, R.; Andersson, B.; Price, L.

1993-01-01

This paper reviews the evolution of energy use in Denmark since the early 1970s, in order to shed light on the future path of energy use in Denmark, with particular emphasis on the role of energy efficiency. Improvements in end-use energy efficiency reduced primary energy requirements in Denmark by 22% between 1972 and 1988. This change accounts for two thirds of the decline in the ratio of energy use to gross domestic product that occurred during this time: the rest of the decline was caused by changes in the mix of goods and services produced and consumed by the Danes. Total energy savings achieved between 1972 and 1988 in Denmark ranked among the highest measured in any major OECD country. Overall, most of the energy savings in Denmark were brought about through improvements in technology. Short-term changes in consumer behaviour were significant in reducing energy needs for space heating and transport. An important stimulus for improved efficiency was higher energy prices, led in no small part by significant taxes imposed on small consumers of heating oil, electricity and motor fuels. (author). 21 refs, 20 figs, 2 tabs

The Importance of using Discounted Cash Flow Methodology in Techno-economic Analyses of Energy and Chemical Production Plants

Directory of Open Access Journals (Sweden)

Zorka Novak Pintarič

2017-06-01

Full Text Available This paper demonstrates the correct application of discounted cash flow methodology forevaluating and designing energy and chemical production plants. Such processes usuallycorrespond to capital intensive long-term projects. Simple economic criteria, like theprofit or production cost are insufficient for this type of decision making because they donot take into account the time value of money and underestimate the profitabilities of theevaluated plants. This paper shows that some of those criteria based on the discountedcash flows establish suitable compromises between long-term cash flow generation andprofitability. As several alternative options are usually evaluated in parallel, it is shownhow to rank mutually exclusive alternatives properly and how to select the best optionfrom among them. Two large-scale case studies demonstrate that using discounted cashflow methodology can result in substantially different decisions than non-discountedcriteria, however, these decisions are affected by several input parameters.

Design of State-of-the-art Flow Cells for Energy Applications

Energy Technology Data Exchange (ETDEWEB)

Yang, Ping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-01-29

The worldwide energy demand is increasing every day and it necessitates rational and efficient usage of renewable energy. Undoubtedly, utilization of renewable energy can address various environmental challenges. However, all current renewable energy resources (wind, solar, and hydroelectric power) are intermittent and fluctuating in their nature that raises an important question of introducing effective energy storage solutions. Utilization of redox flow cells (RFCs) has recently been recognized as a viable technology for large-scale energy storage and, hence, is well suited for integrating renewable energy and balancing electricity grids. In brief, RFC is an electrochemical storage device (Fig. 1), where energy is stored in chemical bonds, similar to a battery, but with reactants external to the cell. The state-of-the-art in flow cell technology uses an aqueous acidic electrolyte and simple metal redox couples. Several of these systems have been commercialized although current technologies, such as vanadium (V) and zinc-bromine (Zn-Br₂) RFCs, for grid level energy storage, suffer from a number of drawbacks, i.e. expensive and resource-limited active materials (vanadium RFCc), and low current performance (Zn-Br₂ RFCs due to Zn dendrite formation). Thus, there is an urgent call to develop efficient (high-energy density) and low-cost RFCs to meet the efflorescent energy storage demands. Approach: To address the first challenge of achieving high-energy density, we plan to design and further modify complexes composed of bifunctional multidentate ligands and specific metal centers, capable of storing as many electrons as possible.

Balance of liquid-phase turbulence kinetic energy equation for bubble-train flow

International Nuclear Information System (INIS)

Ilic, Milica; Woerner, Martin; Cacuci, Dan Gabriel

2004-01-01

In this paper the investigation of bubble-induced turbulence using direct numerical simulation (DNS) of bubbly two-phase flow is reported. DNS computations are performed for a bubble-driven liquid motion induced by a regular train of ellipsoidal bubbles rising through an initially stagnant liquid within a plane vertical channel. DNS data are used to evaluate balance terms in the balance equation for the liquid phase turbulence kinetic energy. The evaluation comprises single-phase-like terms (diffusion, dissipation and production) as well as the interfacial term. Special emphasis is placed on the procedure for evaluation of interfacial quantities. Quantitative analysis of the balance equation for the liquid phase turbulence kinetic energy shows the importance of the interfacial term which is the only source term. The DNS results are further used to validate closure assumptions employed in modelling of the liquid phase turbulence kinetic energy transport in gas-liquid bubbly flows. In this context, the performance of respective closure relations in the transport equation for liquid turbulence kinetic energy within the two-phase k-ε and the two-phase k-l model is evaluated. (author)

Thermal Simulation of a Zero Energy Glazed Pavilion in Sofia, Bulgaria. New Strategies for Energy Management by Means of Water Flow Glazing

Science.gov (United States)

del Ama Gonzalo, Fernando; Hernandez Ramos, Juan A.; Moreno, Belen

2017-10-01

The building sector is primarily responsible for a major part of total energy consumption. The European Energy Performance of Buildings Directives (EPBD) emphasized the need to reduce the energy consumption in buildings, and put forward the rationale for developing Near to Zero Energy Buildings (NZEB). Passive and active strategies help architects to minimize the use of active HVAC systems, taking advantage of the available natural resources such as solar radiation, thermal variability and daylight. The building envelope plays a decisive role in passive and active design strategies. The ideal transparent façade would be one with optical properties, such as Solar Heat Gain Coefficient (SHGC) and Visible Transmittance (VT), that could readily adapt in response to changing climatic conditions or occupant preferences. The aim of this article consists of describing the system to maintain a small glazed pavilion located in Sofia (Bulgaria) at the desired interior temperature over a whole year. The system comprises i) the use of Water Flow Glazing facades (WFG) and Radiant Interior Walls (RIW), ii) the use of free cooling devices along with traditional heat pump connected to photo-voltaic panels and iii) the use of a new Energy Management System that collects data and acts accordingly by controlling all components. The effect of these strategies and the use of active systems, like Water Flow Glazing, are analysed by means of simulating the prototype over one year. Summer and Winter energy management strategies are discussed in order to change the SHGC value of the Water Flow Glazing and thus, reduce the required energy to maintain comfort conditions.

Calculation of quantities of interest in high energy physics using visual basic 3.0. The Flow Tensor Program

International Nuclear Information System (INIS)

Besliu, C.; Jipa, A.; Zaharia, R.

1995-01-01

The Flow Tensor is an important physical quantity in High Energy Physics. The program used for the calculation of the Flow Tensor has been a complex menu-driven application, to allow the selection of various triggers for the studied reaction, of the number of traces in each studied event, of the momentum cut values for the resulting particles of fragments in each event, etc. We realised all that requests using a very modern and powerful tool: Visual Basic 3.0. This programming system allows the realisation of Windows-like programs and has numerous facilities: OLE (Object Linking and Embedding), the possibility to create professional graphics, to work with databases, to create and compile Windows-like help files. All these advantages make the effort to learn Visual Basic 3.0 worthwhile. (author)

PCB Food Web Dynamics Quantify Nutrient and Energy Flow in Aquatic Ecosystems.

Science.gov (United States)

McLeod, Anne M; Paterson, Gordon; Drouillard, Ken G; Haffner, G Douglas

2015-11-03

Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in aquatic food webs. To demonstrate this novel approach, we quantified nitrogen (N), phosphorus (P) and caloric turnover rates for Lake Huron lake trout, and reveal how these processes are regulated by both growth rate and fish life history. Although minimal nutrient recycling was observed in young growing fish, slow growing, older lake trout (>5 yr) recycled an average of 482 Tonnes·yr(-1) of N, 45 Tonnes·yr(-1) of P and assimilated 22 TJ yr(-1) of energy. Compared to total P loading rates of 590 Tonnes·yr(-1), the recycling of primarily bioavailable nutrients by fish plays an important role regulating the nutrient states of oligotrophic lakes.

Modeling Stochastic Energy and Water Consumption to Manage Residential Water Uses

Science.gov (United States)

Abdallah, A. M.; Rosenberg, D. E.; Water; Energy Conservation

2011-12-01

Water energy linkages have received growing attention from the water and energy utilities as utilities recognize that collaborative efforts can implement more effective conservation and efficiency improvement programs at lower cost with less effort. To date, limited energy-water household data has allowed only deterministic analysis for average, representative households and required coarse assumptions - like the water heater (the primary energy use in a home apart from heating and cooling) be a single end use. Here, we use recent available disaggregated hot and cold water household end-use data to estimate water and energy consumption for toilet, shower, faucet, dishwasher, laundry machine, leaks, and other household uses and savings from appliance retrofits. The disaggregated hot water and bulk water end-use data was previously collected by the USEPA for 96 single family households in Seattle WA and Oakland CA, and Tampa FL between the period from 2000 and 2003 for two weeks before and four weeks after each household was retrofitted with water efficient appliances. Using the disaggregated data, we developed a stochastic model that represents factors that influence water use for each appliance: behavioral (use frequency and duration), demographical (household size), and technological (use volume or flowrate). We also include stochastic factors that govern energy to heat hot water: hot water fraction (percentage of hot water volume to total water volume used in a certain end-use event), heater water intake and dispense temperatures, and energy source for the heater (gas, electric, etc). From the empirical household end-use data, we derive stochastic probability distributions for each water and energy factor where each distribution represents the range and likelihood of values that the factor may take. The uncertainty of the stochastic water and energy factors is propagated using Monte Carlo simulations to calculate the composite probability distribution for water

Lower end fitting debris collector and end cap spacer grid

International Nuclear Information System (INIS)

Bryan, W.J.

1990-01-01

This patent describes a nuclear reactor having fuel assemblies including an upper end fitting and spaced nuclear fuel rod spacer grids for supporting and spacing a plurality of elongated nuclear fuel rods. Each includes a hollow active portion of nuclear fuel filled cladding intermediate the rod ends and tapering end cap of solid material with a circumferential groove on the rod end which first encounters reactor coolant flow, a lower end filtering debris collector and end cap spacer grid for capturing and retaining deleterious debris carried by reactor coolant before it enters the active region of a fuel assembly and creates fuel rod cladding damage

Sectoral energy demand studies: Application of the end-use approach to Asian countries

International Nuclear Information System (INIS)

1991-01-01

Events since August 1990 have shown that the world is still dependent on oil despite efforts to decrease that dependency since the oil crisis of 1973 and 1979. Thirteen countries participated in the REDP (UNDP-funded Regional Energy Development Programme) energy planning activities called ''Sectoral energy demand studies'' in which country teams benefited from training in energy data analysis, sectoral accounting of energy demand, and forecasting with the use of MEDEE-S model. This publication documents the training materials on sectoral energy demand series. It includes eight chapters which were indexed separately. Refs, figs, tabs

An Exploration of the Relationship between Improvements in Energy Efficiency and Life-Cycle Energy and Carbon Emissions using the BIRDS Low-Energy Residential Database.

Science.gov (United States)

Kneifel, Joshua; O'Rear, Eric; Webb, David; O'Fallon, Cheyney

2018-02-01

To conduct a more complete analysis of low-energy and net-zero energy buildings that considers both the operating and embodied energy/emissions, members of the building community look to life-cycle assessment (LCA) methods. This paper examines differences in the relative impacts of cost-optimal energy efficiency measure combinations depicting residential buildings up to and beyond net-zero energy consumption on operating and embodied flows using data from the Building Industry Reporting and Design for Sustainability (BIRDS) Low-Energy Residential Database. Results indicate that net-zero performance leads to a large increase in embodied flows (over 40%) that offsets some of the reductions in operational flows, but overall life-cycle flows are still reduced by over 60% relative to the state energy code. Overall, building designs beyond net-zero performance can partially offset embodied flows with negative operational flows by replacing traditional electricity generation with solar production, but would require an additional 8.34 kW (18.54 kW in total) of due south facing solar PV to reach net-zero total life-cycle flows. Such a system would meet over 239% of operational consumption of the most energy efficient design considered in this study and over 116% of a state code-compliant building design in its initial year of operation.

The multi-factor energy input–output model

International Nuclear Information System (INIS)

Guevara, Zeus; Domingos, Tiago

2017-01-01

Energy input–output analysis (EIO analysis) is a noteworthy tool for the analysis of the role of energy in the economy. However, it has relied on models that provide a limited description of energy flows in the economic system and do not allow an adequate analysis of energy efficiency. This paper introduces a novel energy input–output model, the multi-factor energy input–output model (MF-EIO model), which is obtained from a partitioning of a hybrid-unit input–output system of the economy. This model improves on current models by describing the energy flows according to the processes of energy conversion and the levels of energy use in the economy. It characterizes the vector of total energy output as a function of seven factors: two energy efficiency indicators; two characteristics of end-use energy consumption; and three economic features of the rest of the economy. Moreover, it is consistent with the standard model for EIO analysis, i.e., the hybrid-unit model. This paper also introduces an approximate version of the MF-EIO model, which is equivalent to the former under equal energy prices for industries and final consumers, but requires less data processing. The latter is composed by two linked models: a model of the energy sector in physical units, and a model of the rest of the economy in monetary units. In conclusion, the proposed modelling framework improves EIO analysis and extends EIO applications to the accounting for energy efficiency of the economy. - Highlights: • A novel energy input–output model is introduced. • It allows a more adequate analysis of energy flows than current models. • It describes energy flows according to processes of energy conversion and use. • It can be used for other environmental applications (material use and emissions). • An approximate version of the model is introduced, simpler and less data intensive.

Catchment organisation, free energy dynamics and network control on critical zone water flows

Science.gov (United States)

Zehe, E.; Ehret, U.; Kleidon, A.; Jackisch, C.; Scherer, U.; Blume, T.

2012-04-01

processes using the behavioural system architecture and small perturbations and compare them with respect to their efficiency to dissipate free energy which is equivalent to produce entropy. The study will present the underlying theory and discuss simulation results with respect to the following core hypotheses: H1: A macro scale configuration of a hydro-geo-ecosystem, is in stationary non equilibrium closer to a functional optimum as other possible configurations, if it "dissipates" more of the available free energy to maintain the stationary cycles that redistribute and export mass and energy within/from the system. This implies (I1) that the system approaches faster a dynamic equilibrium state characterised by a minimum in free energy, and less free energy from persistent gradients is available to perform work in the system. H2: Macroscopically connected flow networks enhance redistribution of mass against macroscale gradients and thus dissipation of free energy, because they minimise local energy dissipation per unit mass flow along the flow path. This implies (I2) mechanic stability of the flow network, of the textural storage elements and thus of the entire system against frequent disturbances under stationary conditions.