Estimate for interstage water injection in air compressor incorporated into gas-turbine cycles and combined power plants cycles

Science.gov (United States)

Kler, A. M.; Zakharov, Yu. B.; Potanina, Yu. M.

2017-05-01

The objects of study are the gas turbine (GT) plant and combined cycle power plant (CCPP) with opportunity for injection between the stages of air compressor. The objective of this paper is technical and economy optimization calculations for these classes of plants with water interstage injection. The integrated development environment "System of machine building program" was a tool for creating the mathematic models for these classes of power plants. Optimization calculations with the criterion of minimum for specific capital investment as a function of the unit efficiency have been carried out. For a gas-turbine plant, the economic gain from water injection exists for entire range of power efficiency. For the combined cycle plant, the economic benefit was observed only for a certain range of plant's power efficiency.

Evaluation of the energy efficiency of combined cycle gas turbine. Case study of Tashkent thermal power plant, Uzbekistan

International Nuclear Information System (INIS)

Aminov, Zarif; Nakagoshi, Nobukazu; Xuan, Tran Dang; Higashi, Osamu; Alikulov, Khusniddin

2016-01-01

Highlights: • The combined cycle power plant (CCPP) has a steam turbine and a gas turbine. • Fossil fuel savings and reduction of the CCGT of was evaluated. • The performance of a three pressure CCGT is modelled under different modes. • Energy efficiency of the combined cycle was 58.28%. • An annual reduction of 1760.18 tNO_x/annum and 981.25 ktCO_2/annum can be achieved. - Abstract: The power generation of Tashkent Thermal Power Plant (TPP) is based on conventional power units. Moreover, the facility suffers from limited efficiency in electricity generation. The plant was constructed during the Soviet era. Furthermore, the power plant is being used for inter-hour power generation regulation. As a result, the efficiency can be reduced by increasing specific fuel consumption. This research focuses on the evaluation of the energy efficiency of the combined cycle gas turbine (CCGT) for the Tashkent TPP. Specifically, the objective is an evaluation of fossil fuel savings and reduction of CO_2 and NO_x emissions with the using CCGT technology at conventional power plant. The proposed combined cycle power plant (CCPP) includes an existing steam turbine (ST) with 160 MW capacity, heat recovery steam generator (HRSG), and gas turbine (GT) technology with 300 MW capacity. The performance of a three pressure CCGT is modelled under different modes. As a result, the efficiency of the combined cycle was evaluated at 58.28%, while the conventional cycle had an efficiency of 34.5%. We can achieve an annual reduction of 1760.18 tNO_x/annum and 981.25 ktCO_2/annum.

Performance analysis of a bio-gasification based combined cycle power plant employing indirectly heated humid air turbine

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, S., E-mail: sankha.deepp@gmail.com; Mondal, P., E-mail: mondal.pradip87@gmail.com; Ghosh, S., E-mail: sudipghosh.becollege@gmail.com [Department of Mechanical Engineering, Indian Institute of Engineering Science and Technology, Shibpur, Howrah – 711103, West Bengal (India)

2016-07-12

Rapid depletion of fossil fuel has forced mankind to look into alternative fuel resources. In this context, biomass based power generation employing gas turbine appears to be a popular choice. Bio-gasification based combined cycle provides a feasible solution as far as grid-independent power generation is concerned for rural electrification projects. Indirectly heated gas turbine cycles are promising alternatives as they avoid downstream gas cleaning systems. Advanced thermodynamic cycles have become an interesting area of study to improve plant efficiency. Water injected system is one of the most attractive options in this field of applications. This paper presents a theoretical model of a biomass gasification based combined cycle that employs an indirectly heated humid air turbine (HAT) in the topping cycle. Maximum overall electrical efficiency is found to be around 41%. Gas turbine specific air consumption by mass is minimum when pressure ratio is 6. The study reveals that, incorporation of the humidification process helps to improve the overall performance of the plant.

Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part B

DEFF Research Database (Denmark)

La Seta, Angelo; Meroni, Andrea; Andreasen, Jesper Graa

2016-01-01

Organic Rankine cycle (ORC) power systems have recently emerged as promising solutions for waste heat recovery in low- and medium-size power plants. Their performance and economic feasibility strongly depend on the expander. The design process and efficiency estimation are particularly challenging...... due to the peculiar physical properties of the working fluid and the gas-dynamic phenomena occurring in the machine. Unlike steam Rankine and Brayton engines, organic Rankine cycle expanders combine small enthalpy drops with large expansion ratios. These features yield turbine designs with few highly...... is the preliminary design of an organic Rankine cycle turbogenerator to increase the overall energy efficiency of an offshore platform. For an increase in expander pressure ratio from 10 to 35, the results indicate up to 10% point reduction in expander performance. This corresponds to a relative reduction in net...

An advanced conceptual Tokamak fusion power reactor utilizing closed cycle helium gas turbines

International Nuclear Information System (INIS)

Conn, R.W.

1976-01-01

UWMAK-III is a conceptual Tokamak reactor designed to study the potential and the problems associated with an advanced version of Tokamaks as power reactors. Design choices have been made which represent reasonable extrapolations of present technology. The major features are the noncircular plasma cross section, the use of TZM, a molybdenum based alloy, as the primary structural material, and the incorporation of a closed-cycle helium gas turbine power conversion system. A conceptual design of the turbomachinery is given together with a preliminary heat exchanger analysis that results in relatively compact designs for the generator, precooler, and intercooler. This paper contains a general description of the UWMAK-III system and a discussion of those aspects of the reactor, such as the burn cycle, the blanket design and the heat transfer analysis, which are required to form the basis for discussing the power conversion system. The authors concentrate on the power conversion system and include a parametric performance analysis, an interface and trade-off study and a description of the reference conceptual design of the closed-cycle helium gas turbine power conversion system. (Auth.)

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 5: Combined gas-steam turbine cycles. [energy conversion efficiency in electric power plants

Science.gov (United States)

Amos, D. J.; Foster-Pegg, R. W.; Lee, R. M.

1976-01-01

The energy conversion efficiency of gas-steam turbine cycles was investigated for selected combined cycle power plants. Results indicate that it is possible for combined cycle gas-steam turbine power plants to have efficiencies several point higher than conventional steam plants. Induction of low pressure steam into the steam turbine is shown to improve the plant efficiency. Post firing of the boiler of a high temperature combined cycle plant is found to increase net power but to worsen efficiency. A gas turbine pressure ratio of 12 to 1 was found to be close to optimum at all gas turbine inlet temperatures that were studied. The coal using combined cycle plant with an integrated low-Btu gasifier was calculated to have a plant efficiency of 43.6%, a capitalization of $497/kW, and a cost of electricity of 6.75 mills/MJ (24.3 mills/kwh). This combined cycle plant should be considered for base load power generation.

Stabilization of gas turbine unit power

Science.gov (United States)

Dolotovskii, I.; Larin, E.

2017-11-01

We propose a new cycle air preparation unit which helps increasing energy power of gas turbine units (GTU) operating as a part of combined cycle gas turbine (CCGT) units of thermal power stations and energy and water supply systems of industrial enterprises as well as reducing power loss of gas turbine engines of process blowers resulting from variable ambient air temperatures. Installation of GTU power stabilizer at CCGT unit with electric and thermal power of 192 and 163 MW, respectively, has resulted in reduction of produced electrical energy production costs by 2.4% and thermal energy production costs by 1.6% while capital expenditures after installation of this equipment increased insignificantly.

Fast power cycle for fusion reactors

International Nuclear Information System (INIS)

Powell, J.; Fillo, J.; Makowitz, H.

1978-01-01

The unique, deep penetration capability of 14 MeV neutrons produced in DT fusion reactions allows the generation of very high temperature working fluid temperatures in a thermal power cycle. In the FAST (Fusion Augmented Steam Turbine) power cycle steam is directly superheated by the high temperature ceramic refractory interior of the blanket, after being generated by heat extracted from the relatively cool blanket structure. The steam is then passed to a high temperature gas turbine for power generation. Cycle studies have been carried out for a range of turbine inlet temperatures [1600 0 F to 3000 0 F (870 to 1650 0 C)], number of reheats, turbine mechanical efficiency, recuperator effectiveness, and system pressure losses. Gross cycle efficiency is projected to be in the range of 55 to 60%, (fusion energy to electric power), depending on parameters selected. Turbine inlet temperatures above 2000 0 F, while they do increase efficiency somewhat, are not necessarily for high cycle efficiency

Algebraic approach for the diagnosis of turbine cycles in nuclear power plants

International Nuclear Information System (INIS)

Heo, Gyunyoung; Chang, Soon Heung

2005-01-01

According to plant operating staff's practical needs, authors proposed a diagnosis model to identify the performance degradation of steam turbine cycles in nuclear power plants (NPPs). The essential idea of this study is how to identify the intrinsically degraded component which causes electric loss. Authors found that there were not so many turbine cycle diagnosis applications in NPPs currently because of technical, financial, or social characteristics of the plant. So a great part of the diagnosis has been dependent on operating staff's experience and knowledge. However as economic competition becomes severe, the efficiency staffs is asking for reliable and practical advisory tools. For the solution of these shortcomings, authors proposed a simple and intuitive diagnosis concept based on the superposition rule of degradation phenomena, which can be derived by simple algebra and correlation analysis. Though the superposition rule is not so significant statistically, almost all of the performance indices under normal operation are fairly compatible with this model. Authors developed a prototype model of quantitative root-cause diagnosis and validated the background theory using the simulated data. The turbine cycle advisory system using this model was applied to Gori NPP units 3 and 4

Prospects of power conversion technology of direct-cycle helium gas turbine for MHTGR

International Nuclear Information System (INIS)

Li Yong; Zhang Zuoyi

1999-01-01

The modular high temperature gas cooled reactor (MHTGR) is a modern passively safe reactor. The reactor and helium gas turbine may be combined for high efficiency's power conversion, because MHTGR has high outlet temperature up to 950 degree C. Two different schemes are planed separately by USA and South Africa. the helium gas turbine methodologies adopted by them are mainly based on the developed heavy duty industrial and aviation gas turbine technology. The author introduces the differences of two technologies and some design issues in the design and manufacture. Moreover, the author conclude that directly coupling a closed Brayton cycle gas turbine concept to the passively safe MHTGR is the developing direction of MHTGR due to its efficiency which is much higher than that of using steam turbine

Advanced gas turbine cycles a brief review of power generation thermodynamics

CERN Document Server

Horlock, JH

2003-01-01

Primarily this book describes the thermodynamics of gas turbine cycles. The search for high gas turbine efficiency has produced many variations on the simple ""open circuit"" plant, involving the use of heat exchangers, reheating and intercooling, water and steam injection, cogeneration and combined cycle plants. These are described fully in the text. A review of recent proposals for a number of novel gas turbine cycles is also included. In the past few years work has been directed towards developing gas turbines which produce less carbon dioxide, or plants from which the CO2 can be d

Cycle analysis of MCFC/gas turbine system

Directory of Open Access Journals (Sweden)

Musa Abdullatif

2017-01-01

Full Text Available High temperature fuel cells such as the solid oxide fuel cell (SOFC and the molten carbonate fuel cell (MCFC are considered extremely suitable for electrical power plant application. The molten carbonate fuel cell (MCFC performances is evaluated using validated model for the internally reformed (IR fuel cell. This model is integrated in Aspen Plus™. Therefore, several MCFC/Gas Turbine systems are introduced and investigated. One of this a new cycle is called a heat recovery (HR cycle. In the HR cycle, a regenerator is used to preheat water by outlet air compressor. So the waste heat of the outlet air compressor and the exhaust gases of turbine are recovered and used to produce steam. This steam is injected in the gas turbine, resulting in a high specific power and a high thermal efficiency. The cycles are simulated in order to evaluate and compare their performances. Moreover, the effects of an important parameters such as the ambient air temperature on the cycle performance are evaluated. The simulation results show that the HR cycle has high efficiency.

Cycle analysis of MCFC/gas turbine system

Science.gov (United States)

Musa, Abdullatif; Alaktiwi, Abdulsalam; Talbi, Mosbah

2017-11-01

High temperature fuel cells such as the solid oxide fuel cell (SOFC) and the molten carbonate fuel cell (MCFC) are considered extremely suitable for electrical power plant application. The molten carbonate fuel cell (MCFC) performances is evaluated using validated model for the internally reformed (IR) fuel cell. This model is integrated in Aspen Plus™. Therefore, several MCFC/Gas Turbine systems are introduced and investigated. One of this a new cycle is called a heat recovery (HR) cycle. In the HR cycle, a regenerator is used to preheat water by outlet air compressor. So the waste heat of the outlet air compressor and the exhaust gases of turbine are recovered and used to produce steam. This steam is injected in the gas turbine, resulting in a high specific power and a high thermal efficiency. The cycles are simulated in order to evaluate and compare their performances. Moreover, the effects of an important parameters such as the ambient air temperature on the cycle performance are evaluated. The simulation results show that the HR cycle has high efficiency.

Static and dynamic modelling of gas turbines in advanced cycles

Energy Technology Data Exchange (ETDEWEB)

Gustafsson, Jan-Olof

1998-12-01

Gas turbines have been in operation for at least 50 years. The engine is used for propulsion of aircraft and high speed ships. It is used for power production in remote locations and for peak load and emergency situations. Gas turbines have been used in combined cycles for 20 to 30 years. Highly efficient power plants based on gas turbines are a competitive option for the power industry today. The thermal efficiency of the simple cycle gas turbine has increased due to higher turbine inlet temperatures and improved compressor and expander designs. Equally important are the improved cycles in which the gas turbine operates. One example is the combined cycle that uses steam for turbine cooling. Steam is extracted from the bottoming cycle, then used as airfoil coolant in a closed loop and returned to the bottoming cycle. The Evaporative Gas Turbine (EvGT), also known as the Humid Air Turbine (HAT), is another advanced cycle. A mixture of air and water vapour is used as working media. Air from the compressor outlet is humidified and then preheated in a recuperator prior to combustion. The static and dynamic performance is changed when the gas turbine is introduced in an evaporative cycle. The cycle is gaining in popularity, but so far it has not been demonstrated. A Swedish joint program to develop the cycle has been in operation since 1993. As part of the program, a small pilot plant is being erected at the Lund Institute of Technology (LTH). The plant is based on a 600 kW gas turbine, and demonstration of the EvGT cycle started autumn 1998 and will continue, in the present phase, for one year. This thesis presents static and dynamic models for traditional gas turbine components, such as, the compressor, combustor, expander and recuperator. A static model for the humidifier is presented, based on common knowledge for atmospheric humidification. All models were developed for the pilot plant at LTH with the objective to support evaluation of the process and individual

Thermodynamic assessment of a wind turbine based combined cycle

International Nuclear Information System (INIS)

Rabbani, M.; Dincer, I.; Naterer, G.F.

2012-01-01

Combined cycles use the exhaust gases released from a Gas Turbine (GT). Approximately 30–40% of the turbine shaft work is typically used to drive the Compressor. The present study analyzes a system that couples a Wind Turbine (WT) with a combined cycle. It demonstrates how a WT can be used to supply power to the Compressor in the GT cycle and pump fluid through a reheat Rankine cycle, in order to increase the overall power output. Three different configurations are discussed, namely high penetration, low penetration and wind power addition. In the case of a low electricity demand and high penetration configuration, extra wind power is used to compress air which can then be used in the low penetration configuration. During a high load demand, all the wind power is used to drive the pump and compressor and if required additional compressed air is supplied by a storage unit. The analysis shows that increasing the combustion temperature reduces the critical velocity and mass flow rate. Increases in wind speed reduce both energy and exergy efficiency of the overall system. -- Highlights: ► This study analyzes a system that couples a wind turbine with a combined power generation cycle. ► Surplus wind power is used to compress air, which is then stored and used at a later time. ► Increasing the pressure ratio will reduce the work ratio between the Rankine and Brayton cycles. ► A higher combustion temperature will increase the net work output, as well as the system energy and exergy efficiencies.

Performance assessment of simple and modified cycle turboshaft gas turbines

Directory of Open Access Journals (Sweden)

Barinyima Nkoi

2013-06-01

Full Text Available This paper focuses on investigations encompassing comparative assessment of gas turbine cycle options. More specifically, investigation was carried out of technical performance of turboshaft engine cycles based on existing simple cycle (SC and its projected modified cycles for civil helicopter application. Technically, thermal efficiency, specific fuel consumption, and power output are of paramount importance to the overall performance of gas turbine engines. In course of carrying out this research, turbomatch software established at Cranfield University based on gas turbine theory was applied to conduct simulation of a simple cycle (baseline two-spool helicopter turboshaft engine model with free power turbine. Similarly, some modified gas turbine cycle configurations incorporating unconventional components, such as engine cycle with low pressure compressor (LPC zero-staged, recuperated engine cycle, and intercooled/recuperated (ICR engine cycle, were also simulated. In doing so, design point (DP and off-design point (OD performances of the engine models were established. The percentage changes in performance parameters of the modified cycle engines over the simple cycle were evaluated and it was found that to a large extent, the modified engine cycles with unconventional components exhibit better performances in terms of thermal efficiency and specific fuel consumption than the traditional simple cycle engine. This research made use of public domain open source references.

Alternative ORC bottoming cycles FOR combined cycle power plants

International Nuclear Information System (INIS)

Chacartegui, R.; Sanchez, D.; Munoz, J.M.; Sanchez, T.

2009-01-01

In this work, low temperature Organic Rankine Cycles are studied as bottoming cycle in medium and large scale combined cycle power plants. The analysis aims to show the interest of using these alternative cycles with high efficiency heavy duty gas turbines, for example recuperative gas turbines with lower gas turbine exhaust temperatures than in conventional combined cycle gas turbines. The following organic fluids have been considered: R113, R245, isobutene, toluene, cyclohexane and isopentane. Competitive results have been obtained for toluene and cyclohexane ORC combined cycles, with reasonably high global efficiencies. The paper is structured in four main parts. A review of combined cycle and ORC cycle technologies is presented, followed by a thermodynamic analysis of combined cycles with commercial gas turbines and ORC low temperature bottoming cycles. Then, a parametric optimization of an ORC combined cycle plant is performed in order to achieve a better integration between these two technologies. Finally, some economic considerations related to the use of ORC in combined cycles are discussed.

Study on the supercritical CO2 power cycles for landfill gas firing gas turbine bottoming cycle

International Nuclear Information System (INIS)

Kim, Min Seok; Ahn, Yoonhan; Kim, Beomjoo; Lee, Jeong Ik

2016-01-01

In this paper, a comparison of nine supercritical carbon dioxide (S-CO 2 ) bottoming power cycles in conjunction with a topping cycle of landfill gas (LFG) fired 5MWe gas turbine is presented. For the comparison purpose, a sensitivity study of the cycle design parameters for nine different cycles was conducted and each cycle thermodynamic performance is evaluated. In addition, the cycle performance evaluation dependency on the compressor inlet temperature variation is performed to investigate how S-CO 2 cycles sensitive to the heat sink temperature variation. Furthermore, the development of new S-CO 2 cycle layouts is reported and the suggested cycles' performances are compared to the existing cycle layouts. It was found that a recompression cycle is not suitable for the bottoming cycle application, but a partial heating cycle has relatively higher net produced work with a simple layout and small number of components. Although a dual heated and flow split cycle has the highest net produced work, it has disadvantages of having numerous components and complex process which requires more sophisticated operational strategies. This study identified that the recuperation process is much more important than the intercooling process to the S-CO 2 cycle design for increasing the thermal efficiency and the net produced work point of view. - Highlights: • Study of nine S-CO 2 power cycle layouts for a small scale landfill gas power generation application. • Development of new S-CO 2 cycle layouts. • Sensitivity analysis of S-CO 2 cycles to evaluate and compare nine cycles' performances.

Evaluation of material integrity on electricity power steam generator cycles (turbine casing) component

International Nuclear Information System (INIS)

Histori; Benedicta; Farokhi; S A, Soedardjo; Triyadi, Ari; Natsir, M

1999-01-01

The evaluation of material integrity on power steam generator cycles component was done. The test was carried out on casing turbine which is made from Inconel 617. The tested material was taken from t anjung Priok plant . The evaluation was done by metallography analysis using microscope with magnification of 400. From the result, it is shown that the material grains are equiaxed

Analysis of Maisotsenko open gas turbine bottoming cycle

International Nuclear Information System (INIS)

Saghafifar, Mohammad; Gadalla, Mohamed

2015-01-01

Maisotsenko gas turbine cycle (MGTC) is a recently proposed humid air turbine cycle. An air saturator is employed for air heating and humidification purposes in MGTC. In this paper, MGTC is integrated as the bottoming cycle to a topping simple gas turbine as Maisotsenko bottoming cycle (MBC). A thermodynamic optimization is performed to illustrate the advantages and disadvantages of MBC as compared with air bottoming cycle (ABC). Furthermore, detailed sensitivity analysis is reported to present the effect of different operating parameters on the proposed configurations' performance. Efficiency enhancement of 3.7% is reported which results in more than 2600 tonne of natural gas fuel savings per year. - Highlights: • Developed an accurate air saturator model. • Introduced Maisotsenko bottoming cycle (MBC) as a power generation cycle. • Performed Thermodynamic optimization for MBC and air bottoming cycle (ABC). • Performed detailed sensitivity analysis for MBC under different operating conditions. • MBC has higher efficiency and specific net work output as compared to ABC

ORCENT-2, Full Load Steam Turbine Cycle Thermodynamics for LWR Power Plant

International Nuclear Information System (INIS)

Fuller, L.C.

1979-01-01

1 - Description of problem or function: ORCENT-2 performs heat and mass balance calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam, characteristic of contemporary light-water reactors. The program handles both condensing and back-pressure turbine exhaust arrangements. Turbine performance calculations are based on the General Electric Company method for 1800-rpm large steam turbine- generators operating with light-water-cooled nuclear reactors. Output includes all information normally shown on a turbine-cycle heat balance diagram. 2 - Method of solution: The turbine performance calculations follow the procedures outlined in General Electric report GET-6020. ORCENT-2 utilizes the 1967 American Society of Mechanical Engineers (ASME) formulations and procedures for calculating the properties of steam, adapted for ORNL use by D.W. Altom. 3 - Restrictions on the complexity of the problem: Maxima of: 12 feed-water heaters, 5 moisture removal stages in the low-pressure turbine section. ORCENT-2 is limited to 1800-rpm tandem-compound turbine-generators with single- or double-flow high pressure sections and one, two, or three double-flow low-pressure turbine sections. Steam supply for LWR cycles should be between 900 and 1100 psia and slightly wet to 100 degrees F of initial superheat. Generator rating should be greater than 100 MVA

COMBINED CYCLE GAS TURBINE FOR THERMAL POWER STATIONS: EXPERIENCE IN DESIGNING AND OPERATION, PROSPECTS IN APPLICATION

Directory of Open Access Journals (Sweden)

N. V. Karnitsky

2014-01-01

Full Text Available The paper has reviewed main world tendencies in power consumption and power system structure. Main schemes of combined cycle gas turbines have been considered in the paper. The paper contains an operational analysis of CCGT blocks that are operating within the Belarusian energy system. The analysis results have been given in tables showing main operational indices of power blocks

Bottoming micro-Rankine cycles for micro-gas turbines

International Nuclear Information System (INIS)

Invernizzi, Costante; Iora, Paolo; Silva, Paolo

2007-01-01

This paper investigates the possibility of enhancing the performances of micro-gas turbines through the addition of a bottoming organic Rankine cycle which recovers the thermal power of the exhaust gases typically available in the range of 250-300 o C. The ORC cycles are particularly suitable for the recovery of heat from sources at variable temperatures, and for the generation of medium to small electric power. With reference to a micro-gas turbine with a size of about 100 kWe, a combined configuration could increase the net electric power by about 1/3, yielding an increase of the electrical efficiency of up to 40%. A specific analysis of the characteristics of different classes of working fluids is carried out in order to define a procedure to select the most appropriate fluid, capable of satisfying both environmental (ozone depletion potential, global warming potential) and technical (flammability, toxicity, fluid critical temperature and molecular complexity) concerns. Afterwards, a thermodynamic analysis is performed to ascertain the most favourable cycle thermodynamic conditions, from the point of view of heat recovery. Furthermore, a preliminary design of the ORC turbine (number of stages, outer diameter and rotational speed) is carried out

Performance review: PBMR closed cycle gas turbine power plant

International Nuclear Information System (INIS)

Pradeep Kumar, K.N.; Tourlidakis, A.; Pilidis, P.

2001-01-01

Helium is considered as one of the ideal working fluid for closed cycle using nuclear heat source due to its low neutron absorption as well as high thermodynamic properties. The commercial viability of the Helium turbo machinery depends on operational success. The past attempts failed due to poor performances manifested in the form of drop in efficiency, inability to reach maximum load, slow response to the transients etc. Radical changes in the basic design were suggested in some instances as possible solutions. A better understanding of the operational performance is necessary for the detailed design of the plant and the control systems. This paper describes the theory behind the off design and transient modelling of a closed cycle gas turbine plant. A computer simulation model has been created specifically for this cycle. The model has been tested for various turbine entry temperatures along the steady state and its replications at various locations were observed. The paper also looks at the various control methods available for a closed cycle and some of the options were simulated. (author)

Variable geometry gas turbines for improving the part-load performance of marine combined cycles - Combined cycle performance

DEFF Research Database (Denmark)

Haglind, Fredrik

2011-01-01

The part-load performance of combined cycles intended for naval use is of great importance, and it is influenced by the gas turbine configuration and load control strategy. This paper is aimed at quantifying the effects of variable geometry gas turbines on the part-load efficiency for combined...... cycles used for ship propulsion. Moreover, the paper is aimed at developing methodologies and deriving models for part-load simulations suitable for energy system analysis of various components within combined cycle power plants. Two different gas turbine configurations are studied, a two-shaft aero......-derivative configuration and a single-shaft industrial configuration. The results suggest that by the use of variable geometry gas turbines, the combined cycle part-load performance can be improved. In order to minimise the voyage fuel consumption, a combined cycle featuring two-shaft gas turbines with VAN control...

Optimum design and thermodynamic analysis of a gas turbine and ORC combined cycle with recuperators

International Nuclear Information System (INIS)

Cao, Yue; Gao, Yike; Zheng, Ya; Dai, Yiping

2016-01-01

Highlights: • A GT-ORC combined cycle with recuperators was designed. • The effect of the ORC turbine inlet pressure on the combined cycle was examined. • Toluene was a more suitable working fluid for the GT-ORC combined cycle. • The GT-ORC combined cycle performed better than the GT-Rankine combined cycle. • The sensitivity analysis to the ambient temperature was completed. - Abstract: Gas turbines are widely used in distributed power generation because of their high efficiency, low pollution and low operational cost. To further utilize the waste heat from gas turbines, an organic Rankine cycle (ORC) was proposed as the bottoming cycle for gas turbines in this paper. Two recuperators were coupled with the combined cycle to increase the thermal efficiency, and aromatics were chosen as the working fluid for the bottoming cycle. This paper focused on the optimum design and thermodynamic analysis of the gas turbine and ORC (GT-ORC) combined cycle. Results showed that the net power and thermal efficiency of the ORC increased with the ORC turbine inlet pressure and achieved optimum values at a specific pressure based on the optimum criteria. Furthermore, compared with the GT-Rankine combined cycle, the GT-ORC combined cycle had better thermodynamic performance. Toluene was a more suitable working fluid for the GT-ORC combined cycle. Moreover, ambient temperature sensitivity simulations concluded that the GT-ORC combined cycle had a maximum thermal efficiency and the combined cycle net power was mainly determined by the topping gas turbine cycle.

Application of a power recovery system to gas turbine exhaust gases

International Nuclear Information System (INIS)

Baudat, N.P.; James, O.R.

1979-01-01

This paper discusses the application of a power recovery system to recover waste heat from the exhaust gases of gas turbines and convert this energy into shaft horsepower. Also discussed are power cycles, selection of power fluid, equipment selection, and application of the power recovery system to various gas turbines. Several charts and tables are included: process flow diagram, cycle efficiencies, curve for estimating recoverable horsepower

Report on studies on closed cycle MHD power generation; Closed cycle MHD hatsuden kento hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-04-01

Summarized herein are results of the studies on closed cycle MHD (CCMHD) power generation by the study committee. The studied system is based on the MHD gas turbine combined Brayton cycle of about 500,000 kW in output power, firing natural gas as the fuel, and the conceptual design works therefor are completed. The major findings are: the overall plant efficiency: 54.2% at the power transmission side, plot area required per unit power output: 0.04 m{sup 2}/KW, unit construction cost: 251,000 yen/KW, and unit power generation cost: 10.2 yen/KWh. This system will be more operable than the gas turbine combined cycle with steam system, because start-up time, output change rate, optimum load and so on are constrained not on the power generator side but on the gas turbine side. The expected environmental effects include the exhaust gas NOX concentration being equivalent with that associated with the conventional power generator of 2-stage combustion system, quantity of combustion gases to be treated being approximately 40% of that associated with the gas turbine combined cycle, and reduced CO2 gas emissions, resulting from enhanced power generation efficiency. It is expected that the CCMHD system can exhibit higher efficiency than the high-temperature gas turbine combined cycle system. (NEDO)

Thermodynamic analysis of steam-injected advanced gas turbine cycles

Science.gov (United States)

Pandey, Devendra; Bade, Mukund H.

2017-12-01

This paper deals with thermodynamic analysis of steam-injected gas turbine (STIGT) cycle. To analyse the thermodynamic performance of steam-injected gas turbine (STIGT) cycles, a methodology based on pinch analysis is proposed. This graphical methodology is a systematic approach proposed for a selection of gas turbine with steam injection. The developed graphs are useful for selection of steam-injected gas turbine (STIGT) for optimal operation of it and helps designer to take appropriate decision. The selection of steam-injected gas turbine (STIGT) cycle can be done either at minimum steam ratio (ratio of mass flow rate of steam to air) with maximum efficiency or at maximum steam ratio with maximum net work conditions based on the objective of plants designer. Operating the steam injection based advanced gas turbine plant at minimum steam ratio improves efficiency, resulting in reduction of pollution caused by the emission of flue gases. On the other hand, operating plant at maximum steam ratio can result in maximum work output and hence higher available power.

Preliminary Test of Friction disk type turbine for S-CO{sub 2} cycle application

Energy Technology Data Exchange (ETDEWEB)

Baik, Seungjoon; Kim, Hyeon Tae; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

2016-05-15

Due to the relatively mild sodium-CO{sub 2} interaction, the S-CO{sub 2} Brayton cycle can reduce the accident consequence compared to the steam Rankine cycle. Also the S-CO{sub 2} power conversion cycle can achieve high efficiency for SFR core thermal condition. Moreover, the S-CO{sub 2} power cycle can reduce the total cycle footprint due to high density of the working fluid. However, the high pressure operating condition and low viscosity of the fluid cause difficulties in designing appropriate seals and multi-stage turbo machineries. To solve the problem for designing turbo machineries in a creative way, KAIST research team tested a friction disk type turbine concept for the S-CO{sub 2} cycle application. In this paper, the investigation of the Tesla turbine and preliminary test results with compressed air are covered. The KAIST research team investigated a friction disk type turbine, named as Tesla turbine, for the S-CO{sub 2} power cycle applications. Due to the robust design of the fiction disk type, the Tesla turbine technology can be utilized not only for S-CO{sub 2} turbo machinery but also for the multi-phase or sludge flow turbo machinery. The preliminary test of lab-scale Tesla turbine with compressed air was conducted. The high pressure vessel was manufactured for the S-CO{sub 2} operating condition. The test will be concentrated on the turbine efficiency measurement under various conditions and development of the design methodology.

Component design considerations for gas turbine HTGR waste-heat power plant

International Nuclear Information System (INIS)

McDonald, C.F.; Vrable, D.L.

1976-01-01

Component design considerations are described for the ammonia waste-heat power conversion system of a large helium gas-turbine nuclear power plant under development by General Atomic Company. Initial component design work was done for a reference plant with a 3000-MW(t) High-Temperature Gas-Cooled Reactor (HTGR), and this is discussed. Advanced designs now being evaluated include higher core outlet temperature, higher peak system pressures, improved loop configurations, and twin 4000-MW(t) reactor units. Presented are the design considerations of the major components (turbine, condenser, heat input exchanger, and pump) for a supercritical ammonia Rankine waste heat power plant. The combined cycle (nuclear gas turbine and waste-heated plant) has a projected net plant efficiency of over 50 percent. While specifically directed towards a nuclear closed-cycle helium gas-turbine power plant (GT-HTGR), it is postulated that the bottoming waste-heat cycle component design considerations presented could apply to other low-grade-temperature power conversion systems such as geothermal plants

Combined Heat and Power: Coal-Fired Air Turbine (CAT)-Cycle Plant

International Nuclear Information System (INIS)

Lee Recca

1999-01-01

By combining an integrated system with a gas turbine, coal-fired air turbine cycle technology can produce energy at an efficiency rate of over 40%, with capital and operating costs below those of competing conventional systems. Read this fact sheet to discover the additional benefits of this exciting new technology

Optimisation of Combined Cycle Gas Turbine Power Plant in Intraday Market: Riga CHP-2 Example

Science.gov (United States)

Ivanova, P.; Grebesh, E.; Linkevics, O.

2018-02-01

In the research, the influence of optimised combined cycle gas turbine unit - according to the previously developed EM & OM approach with its use in the intraday market - is evaluated on the generation portfolio. It consists of the two combined cycle gas turbine units. The introduced evaluation algorithm saves the power and heat balance before and after the performance of EM & OM approach by making changes in the generation profile of units. The aim of this algorithm is profit maximisation of the generation portfolio. The evaluation algorithm is implemented in multi-paradigm numerical computing environment MATLab on the example of Riga CHP-2. The results show that the use of EM & OM approach in the intraday market can be profitable or unprofitable. It depends on the initial state of generation units in the intraday market and on the content of the generation portfolio.

Modeling of a combined cycle power plant

International Nuclear Information System (INIS)

Faridah Mohamad Idris

2001-01-01

The combined cycle power plant is a non-linear, closed loop system, which consists of high-pressure (HP) superheater, HP evaporator, HP economizer, low-pressure (LP) evaporator, HP drum, HP deaerator, condenser, HP and LP steam turbine and gas turbine. The two types of turbines in the plant for example the gas turbine and the HP and LP steam turbines operate concurrently to generate power to the plant. The exhaust gas which originate from the combustion chamber drives the gas turbine, after which it flows into the heat recovery steam generator (HRSG) to generate superheated steam to be used in driving the HP and LP steam turbines. In this thesis, the combined cycle power plant is modeled at component level using the physical method. Assuming that there is delay in transport, except for the gas turbine system, the mass and heat balances are applied on the components of the plant to derive the governing equations of the components. These time dependent equations, which are of first order differential types, are then solved for the mass and enthalpy of the components. The solutions were simulated using Matlab Simulink using measured plant data. Where necessary there is no plant data available, approximated data were used. The generalized regression neural networks are also used to generate extra sets of simulation data for the HRSG system. Comparisons of the simulation results with its corresponding plant data showed good agreements between the two and indicated that the models developed for the components could be used to represent the combined cycle power plant under study. (author)

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 6: Closed-cycle gas turbine systems. [energy conversion efficiency in electric power plants

Science.gov (United States)

Amos, D. J.; Fentress, W. K.; Stahl, W. F.

1976-01-01

Both recuperated and bottomed closed cycle gas turbine systems in electric power plants were studied. All systems used a pressurizing gas turbine coupled with a pressurized furnace to heat the helium for the closed cycle gas turbine. Steam and organic vapors are used as Rankine bottoming fluids. Although plant efficiencies of over 40% are calculated for some plants, the resultant cost of electricity was found to be 8.75 mills/MJ (31.5 mills/kWh). These plants do not appear practical for coal or oil fired plants.

Study of steam, helium and supercritical CO2 turbine power generations in prototype fusion power reactor

International Nuclear Information System (INIS)

Ishiyama, Shintaro; Muto, Yasushi; Kato, Yasuyoshi; Nishio, Satoshi; Hayashi, Takumi; Nomoto, Yasunobu

2008-01-01

Power generation systems such as steam turbine cycle, helium turbine cycle and supercritical CO 2 (S-CO 2 ) turbine cycle are examined for the prototype nuclear fusion reactor. Their achievable cycle thermal efficiencies are revealed to be 40%, 34% and 42% levels for the heat source outlet coolant temperature of 480degC, respectively, if no other restriction is imposed. In the current technology, however, low temperature divertor heat source is included. In this actual case, the steam turbine system and the S-CO 2 turbine system were compared in the light of cycle efficiency and plant cost. The values of cycle efficiency were 37.7% and 36.4% for the steam cycle and S-CO 2 cycle, respectively. The construction cost was estimated by means of component volume. The volume became 16,590 m 3 and 7240 m 3 for the steam turbine system and S-CO 2 turbine system, respectively. In addition, separation of permeated tritium from the coolant is much easier in S-CO 2 than in H 2 O. Therefore, the S-CO 2 turbine system is recommended to the fusion reactor system than the steam turbine system. (author)

Prospective gas turbine and combined-cycle units for power engineering (a Review)

Science.gov (United States)

Ol'khovskii, G. G.

2013-02-01

The modern state of technology for making gas turbines around the world and heat-recovery combined-cycle units constructed on their basis are considered. The progress achieved in this field by Siemens, Mitsubishi, General Electric, and Alstom is analyzed, and the objectives these companies set forth for themselves for the near and more distant future are discussed. The 375-MW gas turbine unit with an efficiency of 40% produced by Siemens, which is presently the largest one, is subjected to a detailed analysis. The main specific features of this turbine are that the gas turbine unit's hot-path components have purely air cooling, due to which the installation has enhanced maneuverability. The single-shaft combined-cycle plant constructed on the basis of this turbine has a capacity of 570 MW and efficiency higher than 60%. Programs adopted by different companies for development of new-generation gas turbine units firing synthesis gas and fitted with low-emission combustion chambers and new cooling systems are considered. Concepts of rotor blades for new gas turbine units with improved thermal barrier coatings and composite blades different parts of which are made of materials selected in accordance with the conditions of their operation are discussed.

Thermo-economic comparative analysis of gas turbine GT10 integrated with air and steam bottoming cycle

Science.gov (United States)

Czaja, Daniel; Chmielnak, Tadeusz; Lepszy, Sebastian

2014-12-01

A thermodynamic and economic analysis of a GT10 gas turbine integrated with the air bottoming cycle is presented. The results are compared to commercially available combined cycle power plants based on the same gas turbine. The systems under analysis have a better chance of competing with steam bottoming cycle configurations in a small range of the power output capacity. The aim of the calculations is to determine the final cost of electricity generated by the gas turbine air bottoming cycle based on a 25 MW GT10 gas turbine with the exhaust gas mass flow rate of about 80 kg/s. The article shows the results of thermodynamic optimization of the selection of the technological structure of gas turbine air bottoming cycle and of a comparative economic analysis. Quantities are determined that have a decisive impact on the considered units profitability and competitiveness compared to the popular technology based on the steam bottoming cycle. The ultimate quantity that can be compared in the calculations is the cost of 1 MWh of electricity. It should be noted that the systems analyzed herein are power plants where electricity is the only generated product. The performed calculations do not take account of any other (potential) revenues from the sale of energy origin certificates. Keywords: Gas turbine air bottoming cycle, Air bottoming cycle, Gas turbine, GT10

Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

International Nuclear Information System (INIS)

Chan, Yea-Kuang; Tsai, Yu-Ching

2017-01-01

The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Chan, Yea-Kuang; Tsai, Yu-Ching [Institute of Nuclear Energy Research, Taoyuan City, Taiwan (China). Nuclear Engineering Division

2017-03-15

The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

Dynamic performance of a combined gas turbine and air bottoming cycle plant for off-shore applications

DEFF Research Database (Denmark)

Benato, Alberto; Pierobon, Leonardo; Haglind, Fredrik

2014-01-01

and a combined gas turbine coupled with an air bottoming cycle plant. The case study is the Draugen off-shore oil and gas platform, located in the North Sea, Norway. The normal electricity demand is 19 MW, currently covered by two gas turbines generating each 50% of the power demand, while the third turbine......When the Norwegian government introduced the CO2 tax for hydrocarbon fuels, the challenge became to improve the performance of off-shore power systems. An oil and gas platform typically operates on an island (stand-alone system) and the power demand is covered by two or more gas turbines. In order...... to improve the plant performance, a bottoming cycle unit can be added to the gas turbine topping module, thus constituting a combined cycle plant. This paper aims at developing and testing the numerical model simulating the part-load and dynamic behavior of a novel power system, composed of two gas turbines...

Optimisation of Combined Cycle Gas Turbine Power Plant in Intraday Market: Riga CHP-2 Example

Directory of Open Access Journals (Sweden)

Ivanova P.

2018-02-01

Full Text Available In the research, the influence of optimised combined cycle gas turbine unit – according to the previously developed EM & OM approach with its use in the intraday market – is evaluated on the generation portfolio. It consists of the two combined cycle gas turbine units. The introduced evaluation algorithm saves the power and heat balance before and after the performance of EM & OM approach by making changes in the generation profile of units. The aim of this algorithm is profit maximisation of the generation portfolio. The evaluation algorithm is implemented in multi-paradigm numerical computing environment MATLab on the example of Riga CHP-2. The results show that the use of EM & OM approach in the intraday market can be profitable or unprofitable. It depends on the initial state of generation units in the intraday market and on the content of the generation portfolio.

Life cycle assessment of a floating offshore wind turbine

Energy Technology Data Exchange (ETDEWEB)

Weinzettel, Jan [Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Technicka 2, Praha 166 27 (Czech Republic); Charles University in Prague Environment Center, U Krize 8, Prague 158 00 (Czech Republic); Reenaas, Marte; Solli, Christian [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Hertwich, Edgar G. [Industrial Ecology Programme, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)

2009-03-15

A development in wind energy technology towards higher nominal power of the wind turbines is related to the shift of the turbines to better wind conditions. After the shift from onshore to offshore areas, there has been an effort to move further from the sea coast to the deep water areas, which requires floating windmills. Such a concept brings additional environmental impact through higher material demand. To evaluate additional environmental burdens and to find out whether they can be rebalanced or even offset by better wind conditions, a prospective life cycle assessment (LCA) study of one floating concept has been performed and the results are presented in this paper. A comparison with existing LCA studies of conventional offshore wind power and electricity from a natural gas combined cycle is presented. The results indicate similar environmental impacts of electricity production using floating wind power plants as using non-floating offshore wind power plants. The most important stage in the life cycle of the wind power plants is the production of materials. Credits that are connected to recycling these materials at the end-of-life of the power plant are substantial. (author)

Design of a Rankine cycle operating with a passive turbine multi fluid

Energy Technology Data Exchange (ETDEWEB)

Placco, Guilherme M., E-mail: guilhermeplacco@gmail.com [Instituto Tecnológico de Aeronáutica (ITA), São José dos Campos, SP (Brazil); Guimarães, Lamartine N.F., E-mail: guimarae@ieav.cta.br [Instituto de Estudo Avançados (CTA/IEAV), São José dos Campos, SP, (Brazil); Santos, Gabriela S. B., E-mail: siqueira.gsb@gmail.com [Universidade Paulista (UNIP), São José dos Campos, SP (Brazil)

2017-07-01

The Institute of Advanced Studies - IEAv, has been conducting a project called TERRA - 'Fast Advanced Reactors Technology', which aims to study the effects on the working of a Rankine cycle operating with a Multi Fluid Passive Turbine - TPMF. This turbine has the main characteristic operate bladeless using discs arranged in parallel along a rotating axis. After a thorough literature search, we have not found a previous operating Rankine cycle with this kind of turbine. Thus, the work presented here, began its development with few guidelines to follow. It will be presented, of a sucint way, of the design of the parts that makes up a Rankine cycle; the boundary conditions of the cycle; Data acquisition system; the development schedule; assembly of the components; some associated costs and project management. Experimental results thermal conduction through the cycle; the results of net power generated by the turbine and a comparison between thermal energy to mechanical energy in the turbine (efficiency curve). (author)

Design of a Rankine cycle operating with a passive turbine multi fluid

International Nuclear Information System (INIS)

Placco, Guilherme M.; Guimarães, Lamartine N.F.; Santos, Gabriela S. B.

2017-01-01

The Institute of Advanced Studies - IEAv, has been conducting a project called TERRA - 'Fast Advanced Reactors Technology', which aims to study the effects on the working of a Rankine cycle operating with a Multi Fluid Passive Turbine - TPMF. This turbine has the main characteristic operate bladeless using discs arranged in parallel along a rotating axis. After a thorough literature search, we have not found a previous operating Rankine cycle with this kind of turbine. Thus, the work presented here, began its development with few guidelines to follow. It will be presented, of a sucint way, of the design of the parts that makes up a Rankine cycle; the boundary conditions of the cycle; Data acquisition system; the development schedule; assembly of the components; some associated costs and project management. Experimental results thermal conduction through the cycle; the results of net power generated by the turbine and a comparison between thermal energy to mechanical energy in the turbine (efficiency curve). (author)

Thermodynamic analysis of heat recovery steam generator in combined cycle power plant

Directory of Open Access Journals (Sweden)

Ravi Kumar Naradasu

2007-01-01

Full Text Available Combined cycle power plants play an important role in the present energy sector. The main challenge in designing a combined cycle power plant is proper utilization of gas turbine exhaust heat in the steam cycle in order to achieve optimum steam turbine output. Most of the combined cycle developers focused on the gas turbine output and neglected the role of the heat recovery steam generator which strongly affects the overall performance of the combined cycle power plant. The present paper is aimed at optimal utilization of the flue gas recovery heat with different heat recovery steam generator configurations of single pressure and dual pressure. The combined cycle efficiency with different heat recovery steam generator configurations have been analyzed parametrically by using first law and second law of thermodynamics. It is observed that in the dual cycle high pressure steam turbine pressure must be high and low pressure steam turbine pressure must be low for better heat recovery from heat recovery steam generator.

Using neuro-fuzzy based method to develop nuclear turbine cycle model

International Nuclear Information System (INIS)

Chan Yeakuang; Chang Chinjang

2009-01-01

The purpose of this study is to describe a hybrid soft-computing modeling technique used to develop the steam turbine cycle model for nuclear power plants. The technique uses neuro-fuzzy model to predict the generator output. Firstly, the plant past three fuel cycles operating data above 95% load were collected and validated as the baseline performance data set. Then the signal errors for new operating data were detected by comparison with the baseline data set and their allowable range of variations. Finally, the most important parameters were selected as an input of the neuro-fuzzy based steam turbine cycle model. After training and testing with key parameters (i.e. throttle pressure, condenser backpressure, feedwater flow rate, and final feedwater temperature), the proposed model can be used to predict the generator output. The analysis results show this neuro-fuzzy based turbine cycle model can be used to predict the generator output with a good agreement. Moreover, the achievement of this study provides an alternative approach in thermal performance evaluation for nuclear power plants. (author)

Preliminary study of Friction disk type turbine for S-CO_2 cycle application (2016 Autumn Meeting of the KNS)

International Nuclear Information System (INIS)

Baik, Seungjoon; Heo, Jin Young; Kwon, Jinsu; Lee, Jeong Ik

2016-01-01

Among the next generation reactors, a sodium-cooled fast reactor (SFR) with the supercritical carbon dioxide (S-CO_2) Brayton cycle has been suggested as the advanced energy solution. The S-CO_2 power conversion system can achieve high efficiency with the SFR core thermal condition (450-550℃) and also can reduce the total cycle footprint due to high density of the working fluid. Moreover, the S-CO_2 power cycle can reduce the accident consequence compared to the steam Rankine cycle due to the mild sodium-CO_2 interaction. The S-CO_2 power cycle has different characteristic compare to the conventional steam Rankine cycle or gas Brayton cycle. For the turbine section, the expansion ratio is much smaller than the other cycles. Thus, different type of turbine should be evaluated for the advanced S-CO_2 technology and the KAIST research team considered a friction disk type turbine (Tesla turbine) concept for the S-CO_2 cycle applications. In this paper, the test result and analysis of a lab-scale Tesla turbine in the KAIST S-CO_2 experimental facility (S-CO_2PE) are briefly discussed. The KAIST research team investigated a friction disk type turbine, named as Tesla turbine, for the S-CO_2 power cycle applications. The preliminary test of a lab-scale Tesla turbine was conducted with compressed air. The generator, nozzle angle and bearing performances are tested. With the best performing nozzle angle and bearing, the Tesla turbine was tested under various S-CO_2 conditions. As a result, the S-CO_2PE facility generated electricity (0.5-5W). The isentropic efficiency was relatively low (0.8-1.3%). It seemed that, the authors need further study to understand the main mechanism and maximize the efficiency. After developing the design methodology, the design optimization will be conducted to show the applicability of the friction disk type turbine for the S-CO_2 power cycle

Experimental investigation on the off-design performance of a small-sized humid air turbine cycle

International Nuclear Information System (INIS)

Wei, Chenyu; Zang, Shusheng

2013-01-01

This research aimed to study the improvement of the gas turbine performance of a humid air turbine (HAT) cycle at low pressure ratio and at low turbine inlet temperature (TIT). To achieve this goal, an off-design performance test investigation was conducted on a small-sized, two-shaft gas turbine test rig. The test rig consisted of a centrifugal compressor, a centripetal turbine, an individual direct flow flame tube, a free power turbine, a dynamometer, and a saturator with structured packing. Two different conditions were considered for the test investigation: in Case I, the control system kept the fuel flow constant at 57 kg/h, and in Case II, the turbine inlet temperature was kept constant at 665 °C. In Case I, when the air humidity ratio increased from 30 g/kg dry air (DA) to 43 g/kg DA, the power output increased by 3 kW. At the same time, the turbine inlet temperature decreased by 19 °C, and the NO x emissions were reduced from 25 ppm to 16 ppm. In Case II, when the air humidity ratio increased from 48 g/kg DA to 57 g/kg DA, the power output increased by 9.5 kW. Based on the actual gas turbine parts, characteristics, and test conditions, the off-design performance of the HAT cycle was calculated. Upon comparing the measured and calculated results, the HAT cycle was found to perform better than the two-shaft cycle in terms of specific work, efficiency, and specific fuel consumption. The effect of performance improvement became more obvious as the air humidity ratio increased. Under the same inlet air flow, turbine inlet temperature, and power output, the surge margin on compressor curves became enlarged as the humidity ratio increased. The off-design performance of a HAT cycle with regenerator was also investigated. The results show that the highest efficiency can be increased by 3.1%, which will greatly improve the gas turbine performance. -- Highlights: ► We built a flexible small-size test rig of HAT cycle gas turbine and the real test data were

A High Efficiency PSOFC/ATS-Gas Turbine Power System

Energy Technology Data Exchange (ETDEWEB)

W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

2001-02-01

A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.

Estimating the power efficiency of the thermal power plant modernization by using combined-cycle technologies

International Nuclear Information System (INIS)

Hovhannisyan, L.S.; Harutyunyan, N.R.

2013-01-01

The power efficiency of the thermal power plant (TPP) modernization by using combined-cycle technologies is introduced. It is shown that it is possible to achieve the greatest decrease in the specific fuel consumption at modernizing the TPP at the expense of introducing progressive 'know-how' of the electric power generation: for TPP on gas, it is combined-cycle, gas-turbine superstructures of steam-power plants and gas-turbines with heat utilization

INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

International Nuclear Information System (INIS)

Sandvig, Eric; Walling, Gary; Brown, Robert C.; Pletka, Ryan; Radlein, Desmond; Johnson, Warren

2003-01-01

Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MW e ; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system

INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

Energy Technology Data Exchange (ETDEWEB)

Eric Sandvig; Gary Walling; Robert C. Brown; Ryan Pletka; Desmond Radlein; Warren Johnson

2003-03-01

Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MW{sub e}; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system.

Forty years of experience on closed-cycle gas turbines

International Nuclear Information System (INIS)

Keller, C.

1978-01-01

Forty years of experience on closed-cycle gas turbines (CCGT) is emphasized to substantiate the claim that this prime-mover technology is well established. European fossil-fired plants with air as the working fluid have been individually operated over 100,000 hours, have demonstrated very high availability and reliability, and have been economically successful. Following the initial success of the small air closed cycle gas turbine plants, the next step was the exploitation of helium as the working fluid for plants above 50 MWe. The first fossil fired combined power and heat plant at Oberhausen, using a helium turbine, plays an important role for future nuclear systems and this is briefly discussed. The combining of an HTGR and an advanced proven power conversion system (CCGT) represents the most interesting and challenging project. The key to acceptance of the CCGT in the near term is the introduction of a small nuclear cogeneration plant (100 to 300 MWe) that utilizes the waste heat, demonstrating a very high fuel utilization efficiency: aspects of such a plant are outlined. (author)

Preliminary study of Friction disk type turbine for S-CO{sub 2} cycle application (2016 Autumn Meeting of the KNS)

Energy Technology Data Exchange (ETDEWEB)

Baik, Seungjoon; Heo, Jin Young; Kwon, Jinsu; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

2016-10-15

Among the next generation reactors, a sodium-cooled fast reactor (SFR) with the supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle has been suggested as the advanced energy solution. The S-CO{sub 2} power conversion system can achieve high efficiency with the SFR core thermal condition (450-550℃) and also can reduce the total cycle footprint due to high density of the working fluid. Moreover, the S-CO{sub 2} power cycle can reduce the accident consequence compared to the steam Rankine cycle due to the mild sodium-CO{sub 2} interaction. The S-CO{sub 2} power cycle has different characteristic compare to the conventional steam Rankine cycle or gas Brayton cycle. For the turbine section, the expansion ratio is much smaller than the other cycles. Thus, different type of turbine should be evaluated for the advanced S-CO{sub 2} technology and the KAIST research team considered a friction disk type turbine (Tesla turbine) concept for the S-CO{sub 2} cycle applications. In this paper, the test result and analysis of a lab-scale Tesla turbine in the KAIST S-CO{sub 2} experimental facility (S-CO{sub 2}PE) are briefly discussed. The KAIST research team investigated a friction disk type turbine, named as Tesla turbine, for the S-CO{sub 2} power cycle applications. The preliminary test of a lab-scale Tesla turbine was conducted with compressed air. The generator, nozzle angle and bearing performances are tested. With the best performing nozzle angle and bearing, the Tesla turbine was tested under various S-CO{sub 2} conditions. As a result, the S-CO{sub 2}PE facility generated electricity (0.5-5W). The isentropic efficiency was relatively low (0.8-1.3%). It seemed that, the authors need further study to understand the main mechanism and maximize the efficiency. After developing the design methodology, the design optimization will be conducted to show the applicability of the friction disk type turbine for the S-CO{sub 2} power cycle.

Performance analysis of a gas turbine for power generation using syngas as a fuel

International Nuclear Information System (INIS)

Lee, Jong Jun; Cha Kyu Sang; Kim, Tong Seop; Sohn, Jeong Lak; Joo, Yong Jin

2008-01-01

Integrated Gasification Combined Cycle (IGCC) power plant converts coal to syngas, which is mainly composed of hydrogen and carbon monoxide, by the gasification process and produces electric power by the gas and steam turbine combined cycle power plant. The purpose of this study is to investigate the influence of using syngas in a gas turbine, originally designed for natural gas fuel, on its performance. A commercial gas turbine is selected and variations of its performance characteristics due to adopting syngas is analyzed by simulating off-design gas turbine operation. Since the heating value of the syngas is lower, compared to natural gas, IGCC plants require much larger fuel flow rate. This increase the gas flow rate to the turbine and the pressure ratio, leading to far larger power output and higher thermal efficiency. Examination of using two different syngases reveals that the gas turbine performance varies much with the fuel composition

Feasibility of water injection into the turbine coolant to permit gas turbine contingency power for helicopter application

Science.gov (United States)

Vanfossen, G. J.

1983-01-01

A system which would allow a substantially increased output from a turboshaft engine for brief periods in emergency situations with little or no loss of turbine stress rupture life is proposed and studied analytically. The increased engine output is obtained by overtemperaturing the turbine; however, the temperature of the compressor bleed air used for hot section cooling is lowered by injecting and evaporating water. This decrease in cooling air temperature can offset the effect of increased gas temperature and increased shaft speed and thus keep turbine blade stress rupture life constant. The analysis utilized the NASA-Navy-Engine-Program or NNEP computer code to model the turboshaft engine in both design and off-design modes. This report is concerned with the effect of the proposed method of power augmentation on the engine cycle and turbine components. A simple cycle turboshaft engine with a 16:1 pressure ratio and a 1533 K (2760 R) turbine inlet temperature operating at sea level static conditions was studied to determine the possible power increase and the effect on turbine stress rupture life that could be expected using the proposed emergency cooling scheme. The analysis showed a 54 percent increse in output power can be achieved with no loss in gas generator turbine stress rupture life. A 231 K (415 F) rise in turbine inlet temperature is required for this level of augmentation. The required water flow rate was found to be .0109 kg water per kg of engine air flow.

Effect of thermal barrier coatings on the performance of steam and water-cooled gas turbine/steam turbine combined cycle system

Science.gov (United States)

Nainiger, J. J.

1978-01-01

An analytical study was made of the performance of air, steam, and water-cooled gas-turbine/steam turbine combined-cycle systems with and without thermal-barrier coatings. For steam cooling, thermal barrier coatings permit an increase in the turbine inlet temperature from 1205 C (2200 F), resulting in an efficiency improvement of 1.9 percentage points. The maximum specific power improvement with thermal barriers is 32.4 percent, when the turbine inlet temperature is increased from 1425 C (2600 F) to 1675 C (3050 F) and the airfoil temperature is kept the same. For water cooling, the maximum efficiency improvement is 2.2 percentage points at a turbine inlet temperature of 1683 C (3062 F) and the maximum specific power improvement is 36.6 percent by increasing the turbine inlet temperature from 1425 C (2600 F) to 1730 C (3150 F) and keeping the airfoil temperatures the same. These improvements are greater than that obtained with combined cycles using air cooling at a turbine inlet temperature of 1205 C (2200 F). The large temperature differences across the thermal barriers at these high temperatures, however, indicate that thermal stresses may present obstacles to the use of coatings at high turbine inlet temperatures.

``Turbo-KWK `99``. Combined-cycle power stations with gas turbines. Technical meeting; Turbo-KWK `99. Kraft-Waerme-Kopplung mit Gasturbinen. Fachtagung

Energy Technology Data Exchange (ETDEWEB)

1999-09-01

This conference report comprises 18 contributions on the technological success of gas turbines in power generation, e.g.: Maximum power generation efficiency of combined cycle systems, flexibility of power generation, reduction of air pollution, hot gas production for drying processes and environment-friendly cold generation in the pharmaceutical and printing industries. The final contribution presents an outlook to the future.

Thermodynamic modelling and efficiency analysis of a class of real indirectly fired gas turbine cycles

Directory of Open Access Journals (Sweden)

Ma Zheshu

2009-01-01

Full Text Available Indirectly or externally-fired gas-turbines (IFGT or EFGT are novel technology under development for small and medium scale combined power and heat supplies in combination with micro gas turbine technologies mainly for the utilization of the waste heat from the turbine in a recuperative process and the possibility of burning biomass or 'dirty' fuel by employing a high temperature heat exchanger to avoid the combustion gases passing through the turbine. In this paper, by assuming that all fluid friction losses in the compressor and turbine are quantified by a corresponding isentropic efficiency and all global irreversibilities in the high temperature heat exchanger are taken into account by an effective efficiency, a one dimensional model including power output and cycle efficiency formulation is derived for a class of real IFGT cycles. To illustrate and analyze the effect of operational parameters on IFGT efficiency, detailed numerical analysis and figures are produced. The results summarized by figures show that IFGT cycles are most efficient under low compression ratio ranges (3.0-6.0 and fit for low power output circumstances integrating with micro gas turbine technology. The model derived can be used to analyze and forecast performance of real IFGT configurations.

Improving the performances of gas turbines operated on natural gas in combined cycle power plants with application of mathematical models

International Nuclear Information System (INIS)

Dimkovski, Sasho

2014-01-01

The greater energy demand by today society sets a number of new challenges in the energy sector. The climate extremes impose new modes of operation of the power plants, with high flexibility in production. Combined cycle co generative power plants are the latest trend in the energy sector. Their high prevalence is due to the great efficiency and the good environmental characteristics. The main work horse in these cogeneration plants is the gas turbine, which power production and efficiency strongly depends on the external climate conditions. In warmer periods when there is increased demand for electricity, the power production from the gas turbines significantly declines. Because of the high electricity demand from the grid and reduced power production from the gas turbines at the same time, the need for application of appropriate technology for preserving the performances and power of the gas turbines arises. This master thesis explores different methods to improve the power in gas turbines by cooling the air on the compressor inlet, analyzing their applicability and effectiveness in order to choose the optimal method for power augmentation for the climatic conditions in the city Skopje. The master thesis gives detailed analysis of the weather in Skopje and the time frame in which the chosen method is applicable. At the end in the master thesis, the economic feasibility of the given method for power augmentation is clearly calculated, using a model of a power plant and calculating the resulting amount of gained energy, the amount of the initial investment, the cost for maintenance and operation of the equipment. By these calculations the period for initial return of investment is obtained. As an added benefit the positive environmental impacts of the applied technology for inlet air cooling is analyzed. (author)

A nuclear gas turbine perspective: The indirect cycle (IDC) offers a practical solution

International Nuclear Information System (INIS)

McDonald, C.F.

1996-01-01

The current generation of nuclear power plants are based on light water reactors and steam cycle power conversion systems. This coupling yields a power plant efficiency of less than 30% when dry-cooled. By utilizing a higher temperature heat source, and a more efficient prime-mover, the next generation of nuclear power plants have the potential for an efficiency of close to 50%, with attendant fuel savings and reduced heat rejection to the environment. The nuclear closed Brayton cycle (NCBC) gas turbine plant involves the coupling of a high temperature reactor (HTR) and a high efficiency helium gas turbine. Studies over many years have shown the merits of an indirect cycle (IDC) approach in which an intermediate heat exchanger is used to transfer the reactor thermal energy to the prime-mover. The major advantages of this include the following: (1) multipurpose nuclear heat source; (2) gas turbine operation in a clean non-nuclear environment; (3) power conversion system simplicity; and (4) maximum utilization of existing technology. An additional factor, which may dominate the above is that the IDC approach is in concert with the only active gas-cooled reactor program remaining in the world, namely a high temperature test reactor (HTTR) under construction in Japan, the culmination of which will be the demonstration of a viable high temperature nuclear heat source. The major theme of this paper is that the IDC nuclear gas turbine offers a practical NCBC power plant concept for operation in the second or third decades of the 21st century

Development of biomass gasification systems for gas turbine power generation

International Nuclear Information System (INIS)

Larson, E.D.; Svenningsson, P.

1991-01-01

Gas turbines are of interest for biomass applications because, unlike steam turbines, they have relatively high efficiencies and low unit capital costs in the small sizes appropriate for biomass installations. Gasification is a simple and efficient way to make biomass usable in gas turbines. The authors evaluate here the technical requirements for gas turbine power generation with biomass gas and the status of pressurized biomass gasification and hot gas cleanup systems. They also discuss the economics of gasifier-gas turbine cycles and make some comparisons with competing technologies. Their analysis indicates that biomass gasifiers fueling advanced gas turbines are promising for cost-competitive cogeneration and central station power generation. Gasifier-gas turbine systems are not available commercially, but could probably be developed in 3 to 5 years. Extensive past work related to coal gasification and pressurized combustion of solid fuels for gas turbines would be relevant in this effort, as would work on pressurized biomass gasification for methanol synthesis

Preliminary study of nuclear power cogeneration system using gas turbine process

International Nuclear Information System (INIS)

Fumizawa, Motoo; Inaba, Yoshitomo; Hishida, Makoto; Ogawa, Masuro; Ogata, Kann; Yamada, Seiya.

1995-12-01

The Nuclear power generation plant (NPGP) releases smaller amount of carbon dioxide than the fossil power plant for the generation of the unit electrical power. Thus, the NPGP is expected to contribute resolving the ecological problems. It is important to investigate the nuclear power cogeneration system using gas turbine process from the view point that it is better to produce electricity in high thermal efficiency from the high temperature energy. We carried out, in the current preliminary study, the survey and selection of the candidate cycles, then conducted the evaluation of cycle efficiency, the selection of R and D items to be solved for the decision of the optimum cycle. Following this, we evaluated nuclear heat application for intermediate and low temperature level released from gas turbine process and overall efficiency of cogeneration system. As a result, it was clarified that overall efficiency of the direct regenerative cycle was the highest in low temperature region below 200degC, and that of the direct regenerative inter cooling cycle was the highest in middle and high temperature region. (author)

Preliminary study of nuclear power cogeneration system using gas turbine process

Energy Technology Data Exchange (ETDEWEB)

Fumizawa, Motoo; Inaba, Yoshitomo; Hishida, Makoto [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ogawa, Masuro; Ogata, Kann; Yamada, Seiya

1995-12-01

The Nuclear power generation plant (NPGP) releases smaller amount of carbon dioxide than the fossil power plant for the generation of the unit electrical power. Thus, the NPGP is expected to contribute resolving the ecological problems. It is important to investigate the nuclear power cogeneration system using gas turbine process from the view point that it is better to produce electricity in high thermal efficiency from the high temperature energy. We carried out, in the current preliminary study, the survey and selection of the candidate cycles, then conducted the evaluation of cycle efficiency, the selection of R and D items to be solved for the decision of the optimum cycle. Following this, we evaluated nuclear heat application for intermediate and low temperature level released from gas turbine process and overall efficiency of cogeneration system. As a result, it was clarified that overall efficiency of the direct regenerative cycle was the highest in low temperature region below 200degC, and that of the direct regenerative inter cooling cycle was the highest in middle and high temperature region. (author).

Power and efficiency optimization for combined Brayton and inverse Brayton cycles

International Nuclear Information System (INIS)

Zhang Wanli; Chen Lingen; Sun Fengrui

2009-01-01

A thermodynamic model for open combined Brayton and inverse Brayton cycles is established considering the pressure drops of the working fluid along the flow processes and the size constraints of the real power plant using finite time thermodynamics in this paper. There are 11 flow resistances encountered by the gas stream for the combined Brayton and inverse Brayton cycles. Four of these, the friction through the blades and vanes of the compressors and the turbines, are related to the isentropic efficiencies. The remaining flow resistances are always present because of the changes in flow cross-section at the compressor inlet of the top cycle, combustion inlet and outlet, turbine outlet of the top cycle, turbine outlet of the bottom cycle, heat exchanger inlet, and compressor inlet of the bottom cycle. These resistances control the air flow rate and the net power output. The relative pressure drops associated with the flow through various cross-sectional areas are derived as functions of the compressor inlet relative pressure drop of the top cycle. The analytical formulae about the relations between power output, thermal conversion efficiency, and the compressor pressure ratio of the top cycle are derived with the 11 pressure drop losses in the intake, compression, combustion, expansion, and flow process in the piping, the heat transfer loss to the ambient, the irreversible compression and expansion losses in the compressors and the turbines, and the irreversible combustion loss in the combustion chamber. The performance of the model cycle is optimized by adjusting the compressor inlet pressure of the bottom cycle, the air mass flow rate and the distribution of pressure losses along the flow path. It is shown that the power output has a maximum with respect to the compressor inlet pressure of the bottom cycle, the air mass flow rate or any of the overall pressure drops, and the maximized power output has an additional maximum with respect to the compressor pressure

Engineering design and exergy analyses for combustion gas turbine based power generation system

International Nuclear Information System (INIS)

Sue, D.-C.; Chuang, C.-C.

2004-01-01

This paper presents the engineering design and theoretical exergetic analyses of the plant for combustion gas turbine based power generation systems. Exergy analysis is performed based on the first and second laws of thermodynamics for power generation systems. The results show the exergy analyses for a steam cycle system predict the plant efficiency more precisely. The plant efficiency for partial load operation is lower than full load operation. Increasing the pinch points will decrease the combined cycle plant efficiency. The engineering design is based on inlet air-cooling and natural gas preheating for increasing the net power output and efficiency. To evaluate the energy utilization, one combined cycle unit and one cogeneration system, consisting of gas turbine generators, heat recovery steam generators, one steam turbine generator with steam extracted for process have been analyzed. The analytical results are used for engineering design and component selection

Influence of precooling cooling air on the performance of a gas turbine combined cycle

Energy Technology Data Exchange (ETDEWEB)

Kwon, Ik Hwan; Kang, Do Won; Kang, Soo Young; Kim, Tong Seop [Inha Univ., Incheon (Korea, Republic of)

2012-02-15

Cooling of hot sections, especially the turbine nozzle and rotor blades, has a significant impact on gas turbine performance. In this study, the influence of precooling of the cooling air on the performance of gas turbines and their combined cycle plants was investigated. A state of the art F class gas turbine was selected, and its design performance was deliberately simulated using detailed component models including turbine blade cooling. Off design analysis was used to simulate changes in the operating conditions and performance of the gas turbines due to precooling of the cooling air. Thermodynamic and aerodynamic models were used to simulate the performance of the cooled nozzle and rotor blade. In the combined cycle plant, the heat rejected from the cooling air was recovered at the bottoming steam cycle to optimize the overall plant performance. With a 200K decrease of all cooling air stream, an almost 1.78% power upgrade due to increase in main gas flow and a 0.70 percent point efficiency decrease due to the fuel flow increase to maintain design turbine inlet temperature were predicted.

Aeroderivative Pratt & Whitney FT8-3 gas turbine – an interesting solution for power generation

Directory of Open Access Journals (Sweden)

Sorinel-Gicu TALIF

2011-03-01

Full Text Available The intermediate load electric power stations become more and more interesting for theelectric power market in Romania. In this context, the Combined Cycle Power Plants came as a veryattractive solution. This paper presents the results of a study regarding the use of the aeroderivativePratt & Whitney FT8-3 gas turbine, available in Romania, for the electric power generation in aCombined Cycle Power Plant. It is also analyzed the Combined Heat in Power generation with FT8-3gas turbine when saturated steam or hot water are required.

Thermodynamic analysis of a gas turbine cycle equipped with a non-ideal adiabatic model for a double acting Stirling engine

International Nuclear Information System (INIS)

Korlu, Mahmood; Pirkandi, Jamasb; Maroufi, Arman

2017-01-01

Highlights: • A gas turbine cycle equipped with a double acting Stirling engine is proposed. • The hybrid cycle effects, efficiency and power outputs are investigated. • The energy dissipation, the net enthalpy loss and wall heat leakage are considered. • The hybrid cycle improves the efficiency from 23.6 to 38.8%. - Abstract: The aim of this study is to investigate the thermodynamic performance of a gas turbine cycle equipped with a double acting Stirling engine. A portion of gas turbine exhaust gases are allocated to providing the heat required for the Stirling engine. Employing this hybrid cycle improves gas turbine performance and power generation. The double acting Stirling engine is used in this study and the non-ideal adiabatic model is used to numerical solution. The regenerator’s net enthalpy loss, the regenerator’s wall heat leakage, the energy dissipation caused by pressure drops in heat exchangers and regenerator are the losses that were taken into account for the Stirling engine. The hybrid cycle, gas turbine governing equations and Stirling engine analyses are carried out using the Matlab software. The pressure ratio of the compressor, the inlet temperature of turbine, the porosity, length and diameter of the regenerator were chosen as essential parameters in this article. Also the hybrid cycle effects, efficiency and power outputs are investigated. The results show that the hybrid gas turbine and Stirling engine improves the efficiency from 23.6 to 38.8%.

Thermodynamic performance optimization of a combined power/cooling cycle

International Nuclear Information System (INIS)

Pouraghaie, M.; Atashkari, K.; Besarati, S.M.; Nariman-zadeh, N.

2010-01-01

A combined thermal power and cooling cycle has already been proposed in which thermal energy is used to produce work and to generate a sub-ambient temperature stream that is suitable for cooling applications. The cycle uses ammonia-water mixture as working fluid and is a combination of a Rankine cycle and absorption cycle. The very high ammonia vapor concentration, exiting turbine under certain operating conditions, can provide power output as well as refrigeration. In this paper, the goal is to employ multi-objective algorithms for Pareto approach optimization of thermodynamic performance of the cycle. It has been carried out by varying the selected design variables, namely, turbine inlet pressure (P h ), superheater temperature (T superheat ) and condenser temperature (T condensor ). The important conflicting thermodynamic objective functions that have been considered in this study are turbine work (w T ), cooling capacity (q cool ) and thermal efficiency (η th ) of the cycle. It is shown that some interesting and important relationships among optimal objective functions and decision variables involved in the combined cycle can be discovered consequently. Such important relationships as useful optimal design principles would have not been obtained without the use of a multi-objective optimization approach.

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 4: Open recuperated and bottomed gas turbine cycles. [performance prediction and energy conversion efficiency of gas turbines in electric power plants (thermodynamic cycles)

Science.gov (United States)

Amos, D. J.; Grube, J. E.

1976-01-01

Open-cycle recuperated gas turbine plant with inlet temperatures of 1255 to 1644 K (1800 to 2500 F) and recuperators with effectiveness values of 0, 70, 80 and 90% are considered. A 1644 K (2500 F) gas turbine would have a 33.5% plant efficiency in a simple cycle, 37.6% in a recuperated cycle and 47.6% when combined with a sulfur dioxide bottomer. The distillate burning recuperated plant was calculated to produce electricity at a cost of 8.19 mills/MJ (29.5 mills/kWh). Due to their low capital cost $170 to 200 $/kW, the open cycle gas turbine plant should see duty for peaking and intermediate load duty.

Development of turbine cycle performance analyzer using intelligent data mining

Energy Technology Data Exchange (ETDEWEB)

Heo, Gyun Young

2004-02-15

In recent year, the performance enhancement of turbine cycle in nuclear power plants is being highlighted because of worldwide deregulation environment. Especially the first target of operating plants became the reduction of operating cost to compete other power plants. It is known that overhaul interval is closely related to operating cost Author identified that the rapid and reliable performance tests, analysis, and diagnosis play an important role in the control of overhaul interval through field investigation. First the technical road map was proposed to clearly set up the objectives. The controversial issues were summarized into data gathering, analysis tool, and diagnosis method. Author proposed the integrated solution on the basis of intelligent data mining techniques. For the reliable data gathering, the state analyzer composed of statistical regression, wavelet analysis, and neural network was developed. The role of the state analyzer is to estimate unmeasured data and to increase the reliability of the collected data. For the advanced performance analysis, performance analysis toolbox was developed. The purpose of this tool makes analysis process easier and more accurate by providing three novel heat balance diagrams. This tool includes the state analyzer and turbine cycle simulation code. In diagnosis module, the probabilistic technique based on Bayesian network model and the deterministic technique based on algebraical model are provided together. It compromises the uncertainty in diagnosis process and the pin-point capability. All the modules were validated by simulated data as well as actual test data, and some modules are used as industrial applications. We have a lot of thing to be improved in turbine cycle in order to increase plant availability. This study was accomplished to remind the concern about the importance of turbine cycle and to propose the solutions on the basis of academic as well as industrial needs.

Development of turbine cycle performance analyzer using intelligent data mining

International Nuclear Information System (INIS)

Heo, Gyun Young

2004-02-01

In recent year, the performance enhancement of turbine cycle in nuclear power plants is being highlighted because of worldwide deregulation environment. Especially the first target of operating plants became the reduction of operating cost to compete other power plants. It is known that overhaul interval is closely related to operating cost Author identified that the rapid and reliable performance tests, analysis, and diagnosis play an important role in the control of overhaul interval through field investigation. First the technical road map was proposed to clearly set up the objectives. The controversial issues were summarized into data gathering, analysis tool, and diagnosis method. Author proposed the integrated solution on the basis of intelligent data mining techniques. For the reliable data gathering, the state analyzer composed of statistical regression, wavelet analysis, and neural network was developed. The role of the state analyzer is to estimate unmeasured data and to increase the reliability of the collected data. For the advanced performance analysis, performance analysis toolbox was developed. The purpose of this tool makes analysis process easier and more accurate by providing three novel heat balance diagrams. This tool includes the state analyzer and turbine cycle simulation code. In diagnosis module, the probabilistic technique based on Bayesian network model and the deterministic technique based on algebraical model are provided together. It compromises the uncertainty in diagnosis process and the pin-point capability. All the modules were validated by simulated data as well as actual test data, and some modules are used as industrial applications. We have a lot of thing to be improved in turbine cycle in order to increase plant availability. This study was accomplished to remind the concern about the importance of turbine cycle and to propose the solutions on the basis of academic as well as industrial needs

Parametric analysis and optimization for a combined power and refrigeration cycle

International Nuclear Information System (INIS)

Wang Jiangfeng; Dai Yiping; Gao Lin

2008-01-01

A combined power and refrigeration cycle is proposed, which combines the Rankine cycle and the absorption refrigeration cycle. This combined cycle uses a binary ammonia-water mixture as the working fluid and produces both power output and refrigeration output simultaneously with only one heat source. A parametric analysis is conducted to evaluate the effects of thermodynamic parameters on the performance of the combined cycle. It is shown that heat source temperature, environment temperature, refrigeration temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. A parameter optimization is achieved by means of genetic algorithm to reach the maximum exergy efficiency. The optimized exergy efficiency is 43.06% under the given condition

Exergy optimization for a novel combination of organic Rankine cycles, Stirling cycle and direct expander turbines

Science.gov (United States)

Moghimi, Mahdi; Khosravian, Mohammadreza

2018-06-01

In this paper, a novel combination of organic Rankine cycles (ORCs), Stirling cycle and direct expander turbines is modeled and optimized using the genetic algorithm. The Exergy efficiency is considered as an objective function in the genetic algorithm. High efficiency is the main advantage of Stirling cycle, however, it needs nearly isothermal compressor and turbine. Therefore, an argon ORC and a R14 ORC are placed before and after the Striling cycle along with two expander turbines at the end of the line. Each component and cycle of the proposed plant in this article is verified by the previous works available in the literature and good agreement is achieved. The obtained results reveal that 27.98%, 20.86% and 12.90% of the total cold exergy are used by argon ORC, Stirling cycle and R14 ORC, respectively. Therefore, utilization of the Stirling cycle is a good idea for the LNG line cold exergy. The maximum exergy destruction occurs in the heat exchanger after the argon ORC (85.786 kJ/s per one kg/s LNG) due to the wasted cold exergy, which can be used for air conditioning systems in the plant. Finally, it would be shown that the maximum efficiency of the proposed plant is 54.25% and the maximum output power is 355.72 kW.

Exergy optimization for a novel combination of organic Rankine cycles, Stirling cycle and direct expander turbines

Science.gov (United States)

Moghimi, Mahdi; Khosravian, Mohammadreza

2018-01-01

In this paper, a novel combination of organic Rankine cycles (ORCs), Stirling cycle and direct expander turbines is modeled and optimized using the genetic algorithm. The Exergy efficiency is considered as an objective function in the genetic algorithm. High efficiency is the main advantage of Stirling cycle, however, it needs nearly isothermal compressor and turbine. Therefore, an argon ORC and a R14 ORC are placed before and after the Striling cycle along with two expander turbines at the end of the line. Each component and cycle of the proposed plant in this article is verified by the previous works available in the literature and good agreement is achieved. The obtained results reveal that 27.98%, 20.86% and 12.90% of the total cold exergy are used by argon ORC, Stirling cycle and R14 ORC, respectively. Therefore, utilization of the Stirling cycle is a good idea for the LNG line cold exergy. The maximum exergy destruction occurs in the heat exchanger after the argon ORC (85.786 kJ/s per one kg/s LNG) due to the wasted cold exergy, which can be used for air conditioning systems in the plant. Finally, it would be shown that the maximum efficiency of the proposed plant is 54.25% and the maximum output power is 355.72 kW.

Dual-cycle power plant with internal and external heating of a gas turbine circuit

International Nuclear Information System (INIS)

Strach, L.

1976-01-01

The present proposal, after a preceding invention by the same inventor, aims at making possible the increased use of gas turbines in nuclear and coal-fired power plants. This is to be achieved by bringing the temperature of the combustion easily from a maximum of 900 0 C, as may be supplied, e.g., by the cooling media of nuclear reactors, up to the 1,700 to 2,000 0 C required as inlet temperature for gas turbines, with the aid of a fossil-fired recuperator. In fossil and nuclear power plants, gas turbines will more and more substitute steam turbines which affect the environment because of their high waste-heat losses. In coal power plants, only that part of the coal will be gasified whose resulting gas causes internal combustion within the furnace, while the remaining part of the coal is used for external combustion in a tabular heater. In a nuclear power plant, undisturbed maximum generation of electric power is to be achieved, even at reactor outages and shutdown periods for refuelling and maintenance, by almost inertia-free increase of the fossil fuel supply to the furnace (provided an extension of the latter for the capacity of heating the combustion air from room temperature till 1,700 to 2,000 0 C). The hazard of ruptures in the primary heat exchanging system is very low, because it is operated with a relative pressure of nearly zero between reactor coolant and gas turbine circuit. (RW) [de

Survey on the feasibility of high-efficiency gas turbine power generation system; Kokoritsu gas turbine hatsuden system ni kansuru jitsuyo kanosei chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

For higher-efficiency power generation cycle plants with less restrained conditions for a location, the conceptual design of an inter-cooled regenerative two-fluid cycle plant (ISTIG) was attempted using a modified aircraft gas turbine. A high-performance turbo fan engine is used for middle-class power generation. The first stage combustion gas drives the first stage turbine, and its exhaust gas is used for the second stage combustion. Because of two-axial type of high and low pressure, improvement of thermal efficiency is expected by easy-to-install inter-cooler. ISTIG superior in operability is suitable for medium load or distributed power generation facilities, and aims at higher efficiency of a 60% level. ISTIG includes a large amount of water vapor in combustion air by adopting a diffusion type combustor eliminating back fire, and can reduce exergy loss by preheating fuel gas. Since load of the high-pressure turbine shifts toward low-pressure one by the inter-cooler, some considerations are necessary for low-pressure side cooling together with reheating cycle. Because of unnecessary steam turbine, the construction cost per kW can be reduced by 20%. 41 refs., 64 figs., 27 tabs.

SMART POWER TURBINE

Energy Technology Data Exchange (ETDEWEB)

Nirm V. Nirmalan

2003-11-01

Gas turbines are the choice technology for high-performance power generation and are employed in both simple and combined cycle configurations around the world. The Smart Power Turbine (SPT) program has developed new technologies that are needed to further extend the performance and economic attractiveness of gas turbines for power generation. Today's power generation gas turbines control firing temperatures indirectly, by measuring the exhaust gas temperature and then mathematically calculating the peak combustor temperatures. But temperatures in the turbine hot gas path vary a great deal, making it difficult to control firing temperatures precisely enough to achieve optimal performance. Similarly, there is no current way to assess deterioration of turbine hot-gas-path components without shutting down the turbine. Consequently, maintenance and component replacements are often scheduled according to conservative design practices based on historical fleet-averaged data. Since fuel heating values vary with the prevalent natural gas fuel, the inability to measure heating value directly, with sufficient accuracy and timeliness, can lead to maintenance and operational decisions that are less than optimal. GE Global Research Center, under this Smart Power Turbine program, has developed a suite of novel sensors that would measure combustor flame temperature, online fuel lower heating value (LHV), and hot-gas-path component life directly. The feasibility of using the ratio of the integrated intensities of portions of the OH emission band to determine the specific average temperature of a premixed methane or natural-gas-fueled combustion flame was demonstrated. The temperature determined is the temperature of the plasma included in the field of view of the sensor. Two sensor types were investigated: the first used a low-resolution fiber optic spectrometer; the second was a SiC dual photodiode chip. Both methods worked. Sensitivity to flame temperature changes was

General characteristics and technical subjects on helium closed cycle gas turbine

International Nuclear Information System (INIS)

Shimomura, Hiroaki

1996-06-01

Making the subjects clarified on nuclear-heated gas turbine that will apply the inherent features of HTGR, the present paper discusses the difference of the helium closed cycle gas turbine, which is a candidate of nuclear gas turbine, with the open cycle gas turbine and indicates inherent problems of closed cycle gas turbine, its effects onto thermal efficiency and turbine output and difficulties due to the pressure ratio and specific speed from use of helium. The paper also discusses effects of the external pressure losses onto the efficiencies of compressor and turbine that are major components of the gas turbine. According to the discussions above, the paper concludes indicating the key idea on heat exchangers for the closed cycle gas turbine and design basis to solve the problems and finally offers new gas turbine conception using nitrogen or air that is changeable into open cycle gas turbine. (author)

Fiscal 1980 Sunshine Project research report. Development of hydrothermal power plant. Development of binary cycle power plant (Research on heat cycle, heat medium, material and heat medium turbine); 1980 nendo nessui riyo hatsuden plant no kaihatsu seika hokokusho. Binary cycle hatsuden plant no kaihatsu (netsu cycle oyobi netsubaitai no kenkyu, zairyo no kenkyu narabini netsubaitai turbine no kenkyu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-03-01

This report summarizes the fiscal 1980 research result on each element of the next 10MW class geothermal binary cycle power plant, following last year. In the research on heat cycle and heat medium, measurement was made on the liquid density, vapor density, liquid specific heat, vapor specific heat and thermal conductivity of 8 heat media to prepare the precise pressure enthalpy chart. The thermal stability of each medium was also measured under a flow condition. The heat cycle of each medium was calculated in a hydrothermal temperature range of 120-160 degrees C for evaluation of its output. In the research on material, field corrosion test and laboratory simulation were made on 3 kinds of heat exchanger martials for acidic hot water to study the corrosion behavior of welding members. In the research on heat medium turbine, study was made on sealing characteristics such as differential pressure, flow rate and friction of sealing oil for oil film seal and mechanical seal as shaft seal devices of heat medium turbines for the 10MW class geothermal plant. (NEDO)

Nuclear steam power plant cycle performance calculations supported by power plant monitoring and results computer

International Nuclear Information System (INIS)

Bettes, R.S.

1984-01-01

The paper discusses the real time performance calculations for the turbine cycle and reactor and steam generators of a nuclear power plant. Program accepts plant measurements and calculates performance and efficiency of each part of the cycle: reactor and steam generators, turbines, feedwater heaters, condenser, circulating water system, feed pump turbines, cooling towers. Presently, the calculations involve: 500 inputs, 2400 separate calculations, 500 steam properties subroutine calls, 200 support function accesses, 1500 output valves. The program operates in a real time system at regular intervals

Thermodynamic and design considerations of organic Rankine cycles in combined application with a solar thermal gas turbine

Science.gov (United States)

Braun, R.; Kusterer, K.; Sugimoto, T.; Tanimura, K.; Bohn, D.

2013-12-01

Concentrated Solar Power (CSP) technologies are considered to provide a significant contribution for the electric power production in the future. Different kinds of technologies are presently in operation or under development, e.g. parabolic troughs, central receivers, solar dish systems and Fresnel reflectors. This paper takes the focus on central receiver technologies, where the solar radiation is concentrated by a field of heliostats in a receiver on the top of a tall tower. To get this CSP technology ready for the future, the system costs have to reduce significantly. The main cost driver in such kind of CSP technologies are the huge amount of heliostats. To reduce the amount of heliostats, and so the investment costs, the efficiency of the energy conversion cycle becomes an important issue. An increase in the cycle efficiency results in a decrease of the solar heliostat field and thus, in a significant cost reduction. The paper presents the results of a thermodynamic model of an Organic Rankine Cycle (ORC) for combined cycle application together with a solar thermal gas turbine. The gas turbine cycle is modeled with an additional intercooler and recuperator and is based on a typical industrial gas turbine in the 2 MW class. The gas turbine has a two stage radial compressor and a three stage axial turbine. The compressed air is preheated within a solar receiver to 950°C before entering the combustor. A hybrid operation of the gas turbine is considered. In order to achieve a further increase of the overall efficiency, the combined operation of the gas turbine and an Organic Rankine Cycle is considered. Therefore an ORC has been set up, which is thermally connected to the gas turbine cycle at two positions. The ORC can be coupled to the solar-thermal gas turbine cycle at the intercooler and after the recuperator. Thus, waste heat from different cycle positions can be transferred to the ORC for additional production of electricity. Within this investigation

Wind power electricity: the bigger the turbine, the greener the electricity?

Science.gov (United States)

Caduff, Marloes; Huijbregts, Mark A J; Althaus, Hans-Joerg; Koehler, Annette; Hellweg, Stefanie

2012-05-01

Wind energy is a fast-growing and promising renewable energy source. The investment costs of wind turbines have decreased over the years, making wind energy economically competitive to conventionally produced electricity. Size scaling in the form of a power law, experience curves and progress rates are used to estimate the cost development of ever-larger turbines. In life cycle assessment, scaling and progress rates are seldom applied to estimate the environmental impacts of wind energy. This study quantifies whether the trend toward larger turbines affects the environmental profile of the generated electricity. Previously published life cycle inventories were combined with an engineering-based scaling approach as well as European wind power statistics. The results showed that the larger the turbine is, the greener the electricity becomes. This effect was caused by pure size effects of the turbine (micro level) as well as learning and experience with the technology over time (macro level). The environmental progress rate was 86%, indicating that for every cumulative production doubling, the global warming potential per kWh was reduced by 14%. The parameters, hub height and rotor diameter were identified as Environmental Key Performance Indicators that can be used to estimate the environmental impacts for a generic turbine. © 2012 American Chemical Society

Helium turbomachinery operating experience from gas turbine power plants and test facilities

International Nuclear Information System (INIS)

McDonald, Colin F.

2012-01-01

The closed-cycle gas turbine, pioneered and deployed in Europe, is not well known in the USA. Since nuclear power plant studies currently being conducted in several countries involve the coupling of a high temperature gas-cooled nuclear reactor with a helium closed-cycle gas turbine power conversion system, the experience gained from operated helium turbomachinery is the focus of this paper. A study done as early as 1945 foresaw the use of a helium closed-cycle gas turbine coupled with a high temperature gas-cooled nuclear reactor, and some two decades later this was investigated but not implemented because of lack of technology readiness. However, the first practical use of helium as a gas turbine working fluid was recognized for cryogenic processes, and the first two small fossil-fired helium gas turbines to operate were in the USA for air liquefaction and nitrogen production facilities. In the 1970's a larger helium gas turbine plant and helium test facilities were built and operated in Germany to establish technology bases for a projected future high efficiency large nuclear gas turbine power plant concept. This review paper covers the experience gained, and the lessons learned from the operation of helium gas turbine plants and related test facilities, and puts these into perspective since over three decades have passed since they were deployed. An understanding of the many unexpected events encountered, and how the problems, some of them serious, were resolved is important to avoid them being replicated in future helium turbomachines. The valuable lessons learned in the past, in many cases the hard way, particularly from the operation in Germany of the Oberhausen II 50 MWe helium gas turbine plant, and the technical know-how gained from the formidable HHV helium turbine test facility, are viewed as being germane in the context of current helium turbomachine design work being done for future high efficiency nuclear gas turbine plant concepts. - Highlights: �

Exergy analysis of a combined power and cooling cycle

International Nuclear Information System (INIS)

Fontalvo, Armando; Pinzon, Horacio; Duarte, Jorge; Bula, Antonio; Quiroga, Arturo Gonzalez; Padilla, Ricardo Vasquez

2013-01-01

This paper presents a comprehensive exergy analysis of a combined power and cooling cycle which combines a Rankine and absorption refrigeration cycle by using ammonia–water mixture as working fluid. A thermodynamic model was developed in Matlab ® to find out the effect of pressure ratio, ammonia mass fraction at the absorber and turbine efficiency on the total exergy destruction of the cycle. The contribution of each cycle component on the total exergy destruction was also determined. The results showed that total exergy destruction decreases when pressure ratio increases, and reaches a maximum at x ≈ 0.5, when ammonia mass fraction is varied at absorber. Also, it was found that the absorber, the boiler and the turbine had the major contribution to the total exergy destruction of the cycle, and the increase of the turbine efficiency reduces the total exergy destruction. The effect of rectification cooling source (external and internal) on the cycle output was investigated, and the results showed that internal rectification cooling reduces the total exergy destruction of the cycle. Finally, the effect of the presence or absence of the superheater after the rectification process was determined and it was obtained that the superheated condition reduces the exergy destruction of the cycle at high turbine efficiency values. Highlights: • A parametric exergy analysis of a combined power and cooling cycle is performed. • Two scenarios for rectifier cooling (internal and external) were studied. • Internal cooling source is more exergetic efficient than external cooling source. • The absorber and boiler have the largest total exergy destruction. • Our results show that the superheater reduces the exergy destruction of the cycle

Dynamics and control modeling of the closed-cycle gas turbine (GT-HTGR) power plant

International Nuclear Information System (INIS)

Bardia, A.

1980-02-01

The simulation if presented for the 800-MW(e) two-loop GT-HTGR plant design with the REALY2 transient analysis computer code, and the modeling of control strategies called for by the inherently unique operational requirements of a multiple loop GT-HTGR is described. Plant control of the GT-HTGR is constrained by the nature of its power conversion loops (PCLs) in which the core cooling flow and the turbine flow are directly related and thus changes in flow affect core cooling as well as turbine power. Additionally, the high thermal inertia of the reactor core precludes rapid changes in the temperature of the turbine inlet flow

Parametric analysis for a new combined power and ejector-absorption refrigeration cycle

International Nuclear Information System (INIS)

Wang Jiangfeng; Dai Yiping; Zhang Taiyong; Ma Shaolin

2009-01-01

A new combined power and ejector-absorption refrigeration cycle is proposed, which combines the Rankine cycle and the ejector-absorption refrigeration cycle, and could produce both power output and refrigeration output simultaneously. This combined cycle, which originates from the cycle proposed by authors previously, introduces an ejector between the rectifier and the condenser, and provides a performance improvement without greatly increasing the complexity of the system. A parametric analysis is conducted to evaluate the effects of the key thermodynamic parameters on the cycle performance. It is shown that heat source temperature, condenser temperature, evaporator temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. It is evident that the ejector can improve the performance of the combined cycle proposed by authors previously.

Generating power at high efficiency combined cycle technology for sustainable energy production

CERN Document Server

Jeffs, E

2008-01-01

Combined cycle technology is used to generate power at one of the highest levels of efficiency of conventional power plants. It does this through primary generation from a gas turbine coupled with secondary generation from a steam turbine powered by primary exhaust heat. Generating power at high efficiency thoroughly charts the development and implementation of this technology in power plants and looks to the future of the technology, noting the advantages of the most important technical features - including gas turbines, steam generator, combined heat and power and integrated gasification com

Performance and environment as objectives in multi-criterion optimization of steam injected gas turbine cycles

International Nuclear Information System (INIS)

Kayadelen, Hasan Kayhan; Ust, Yasin

2014-01-01

Rapidly growing demand for gas turbines promotes research on their performance improvement and reducing their exhaust pollutants. Even small increments in net power or thermal efficiency and small changes in pollutant emissions have become significant concerns for both new designs and cycle modifications. To fulfill these requirements an accurate performance evaluation method which enables to see the effects on the exhaust gas composition is an important necessity. To fill this gap, a thermo-ecologic performance evaluation approach for gas turbine cycles with chemical equilibrium approximation which enables performance and environmental aspects to be considered simultaneously, is presented in this work. Steam injection is an effective modification to boost power and limit NO x emissions for gas turbine systems. Steam injection also increases thermal efficiency so less fuel is burnt to maintain the same power output. Because of its performance related and environmental advantages, presented approach is applied on the steam injected gas turbine cycle and a precise multi-criterion optimization is carried out for varying steam injection, as well as equivalence and pressure ratios. Irreversibilities and pressure losses are also considered. Effects of each parameter on the net work and thermal efficiency as well as non-equilibrium NO x and CO emissions are demonstrated. Precision improvement of the presented thermo-ecological model is shown and two main concerns; constant turbine inlet condition for higher net work output and constant net work output condition for lower fuel consumption are compared. - Highlights: • A thermodynamically precise performance estimation tool for GT cycles is presented. • STIG application is provided to show its flexibility for any GT cycle and diluents. • Constant TIT and net work output conditions have been compared and discussed. • The model provides results to evaluate economic and environmental aspects together. • It provides a

Exergy analysis, parametric analysis and optimization for a novel combined power and ejector refrigeration cycle

International Nuclear Information System (INIS)

Dai Yiping; Wang Jiangfeng; Gao Lin

2009-01-01

A new combined power and refrigeration cycle is proposed, which combines the Rankine cycle and the ejector refrigeration cycle. This combined cycle produces both power output and refrigeration output simultaneously. It can be driven by the flue gas of gas turbine or engine, solar energy, geothermal energy and industrial waste heats. An exergy analysis is performed to guide the thermodynamic improvement for this cycle. And a parametric analysis is conducted to evaluate the effects of the key thermodynamic parameters on the performance of the combined cycle. In addition, a parameter optimization is achieved by means of genetic algorithm to reach the maximum exergy efficiency. The results show that the biggest exergy loss due to the irreversibility occurs in heat addition processes, and the ejector causes the next largest exergy loss. It is also shown that the turbine inlet pressure, the turbine back pressure, the condenser temperature and the evaporator temperature have significant effects on the turbine power output, refrigeration output and exergy efficiency of the combined cycle. The optimized exergy efficiency is 27.10% under the given condition.

Parametric study of power turbine for diesel engine waste heat recovery

International Nuclear Information System (INIS)

Zhao, Rongchao; Zhuge, Weilin; Zhang, Yangjun; Yin, Yong; Chen, Zhen; Li, Zhigang

2014-01-01

Turbocompounding is a promising technology to recover waste heat from the exhaust and reduce fuel consumption for internal combustion engine. The design of a power turbine plays a key role in turbocompound engine performance. This paper presents a set of parametric studies of power turbine performed on a turbocompound diesel engine by means of turbine through-flow model developed by the authors. This simulation model was verified and validated using engine performance test data and achieved reasonable accuracy. The paper first analyzed the influence of three key geometrical parameters (blade height, blade radius and nozzle exit blade angle) on turbine expansion ratio and engine fuel consumptions. After that, the impacts of the geometrical parameters on power distribution, air mass flow rate and exhaust temperature were analyzed. Results showed that these parameters had significant effects on engine BSFC and power. At high engine speeds, there existed an optimum value of geometry parameter to obtain the lowest BSFC. At low engine speeds, the engine BSFC kept increasing or decreasing continuously as the geometry parameters changed. Research also found that the engine BSFC was most sensitive to the nozzle exit blade angle, which should be considered carefully during the design process. This paper provides a useful method for matching and designing of a power turbine for turbocompound engine. - Highlights: •Through-flow model of axial-flow power turbine for turbocompound engine was established. •Turbocompound engine performance test was carried out to validate the cycle simulation model. •Influences of power turbine geometry parameters on engine BSFC and power were presented

A Comparison of Organic and Steam Rankine Cycle Power Systems for Waste Heat Recovery on Large Ships

Directory of Open Access Journals (Sweden)

Jesper Graa Andreasen

2017-04-01

Full Text Available This paper presents a comparison of the conventional dual pressure steam Rankine cycle process and the organic Rankine cycle process for marine engine waste heat recovery. The comparison was based on a container vessel, and results are presented for a high-sulfur (3 wt % and low-sulfur (0.5 wt % fuel case. The processes were compared based on their off-design performance for diesel engine loads in the range between 25% and 100%. The fluids considered in the organic Rankine cycle process were MM(hexamethyldisiloxane, toluene, n-pentane, i-pentane and c-pentane. The results of the comparison indicate that the net power output of the steam Rankine cycle process is higher at high engine loads, while the performance of the organic Rankine cycle units is higher at lower loads. Preliminary turbine design considerations suggest that higher turbine efficiencies can be obtained for the ORC unit turbines compared to the steam turbines. When the efficiency of the c-pentane turbine was allowed to be 10% points larger than the steam turbine efficiency, the organic Rankine cycle unit reaches higher net power outputs than the steam Rankine cycle unit at all engine loads for the low-sulfur fuel case. The net power production from the waste heat recovery units is generally higher for the low-sulfur fuel case. The steam Rankine cycle unit produces 18% more power at design compared to the high-sulfur fuel case, while the organic Rankine cycle unit using MM produces 33% more power.

Development of micro-scale axial and radial turbines for low-temperature heat source driven organic Rankine cycle

International Nuclear Information System (INIS)

Al Jubori, Ayad; Daabo, Ahmed; Al-Dadah, Raya K.; Mahmoud, Saad; Ennil, Ali Bahr

2016-01-01

Highlights: • One and three-dimensional analysis with real gas properties are integrated. • Micro axial and radial-inflow turbines configurations are investigated. • Five organic working fluids are considered. • The maximum total isentropic efficiency of radial-inflow turbine 83.85%. • The maximum ORC thermal efficiency based on radial-inflow turbine is 10.60%. - Abstract: Most studies on the organic Rankine cycle (ORC) focused on parametric studies and selection working fluids to maximize the performance of organic Rankine cycle but without attention for turbine design features which are crucial to achieving them. The rotational speed, expansion ratio, mass flow rate and turbine size have markedly effect on turbine performance. For this purpose organic Rankine cycle modeling, mean-line design and three-dimensional computational fluid dynamics analysis were integrated for both micro axial and radial-inflow turbines with five organic fluids (R141b, R1234yf, R245fa, n-butane and n-pentane) for realistic low-temperature heat source <100 °C like solar and geothermal energy. Three-dimensional simulation is performed using ANSYS"R"1"7-CFX where three-dimensional Reynolds-averaged Navier-Stokes equations are solved with k-omega shear stress transport turbulence model. Both configurations of turbines are designed at wide range of mass flow rate (0.1–0.5) kg/s for each working fluid. The results showed that n-pentane has the highest performance at all design conditions where the maximum total-to-total efficiency and power output of radial-inflow turbine are 83.85% and 8.893 kW respectively. The performance of the axial turbine was 83.48% total-to-total efficiency and 8.507 kW power output. The maximum overall size of axial turbine was 64.685 mm compared with 70.97 mm for radial-inflow turbine. R245fa has the lowest overall size for all cases. The organic Rankine cycle thermal efficiency was about 10.60% with radial-inflow turbine and 10.14% with axial turbine

Performance analysis and optimization of power plants with gas turbines

Science.gov (United States)

Besharati-Givi, Maryam

The gas turbine is one of the most important applications for power generation. The purpose of this research is performance analysis and optimization of power plants by using different design systems at different operation conditions. In this research, accurate efficiency calculation and finding optimum values of efficiency for design of chiller inlet cooling and blade cooled gas turbine are investigated. This research shows how it is possible to find the optimum design for different operation conditions, like ambient temperature, relative humidity, turbine inlet temperature, and compressor pressure ratio. The simulated designs include the chiller, with varied COP and fogging cooling for a compressor. In addition, the overall thermal efficiency is improved by adding some design systems like reheat and regenerative heating. The other goal of this research focuses on the blade-cooled gas turbine for higher turbine inlet temperature, and consequently, higher efficiency. New film cooling equations, along with changing film cooling effectiveness for optimum cooling air requirement at the first-stage blades, and an internal and trailing edge cooling for the second stage, are innovated for optimal efficiency calculation. This research sets the groundwork for using the optimum value of efficiency calculation, while using inlet cooling and blade cooling designs. In the final step, the designed systems in the gas cycles are combined with a steam cycle for performance improvement.

Performance analysis of a combined organic Rankine cycle and vapor compression cycle for power and refrigeration cogeneration

International Nuclear Information System (INIS)

Kim, Kyoung Hoon; Perez-Blanco, Horacio

2015-01-01

A thermodynamic analysis of cogeneration of power and refrigeration activated by low-grade sensible energy is presented in this work. An organic Rankine cycle (ORC) for power production and a vapor compression cycle (VCC) for refrigeration using the same working fluid are linked in the analysis, including the limiting case of cold production without net electricity production. We investigate the effects of key parameters on system performance such as net power production, refrigeration, and thermal and exergy efficiencies. Characteristic indexes proportional to the cost of heat exchangers or of turbines, such as total number of transfer units (NTU tot ), size parameter (SP) and isentropic volumetric flow ratio (VFR) are also examined. Three important system parameters are selected, namely turbine inlet temperature, turbine inlet pressure, and the flow division ratio. The analysis is conducted for several different working fluids. For a few special cases, isobutane is used for a sensitivity analysis due to its relatively high efficiencies. Our results show that the system has the potential to effectively use low grade thermal sources. System performance depends both on the adopted parameters and working fluid. - Highlights: • Waste heat utilization can reduce emissions of carbon dioxide. • The ORC/VCC cycle can deliver power and/or refrigeration using waste heat. • Efficiencies and size parameters are used for cycle evaluation. • The cycle performance is studied for eight suitable refrigerants. Isobutane is used for a sensitivity analysis. • The work shows that the isobutene cycle is quite promising.

Feasibility improvement project for the gas turbine power plant in Iran

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Investigations and discussions have been given on measures to improve energy conservation and efficiency at a power plant of Kish Water and Power Company (KWPC) in Iran. The site has high ambient temperature throughout a year, making the gas turbine power plant capable of generating power only at about 70% of the rated output, with the power generation efficiency decreasing. The project has analyzed the current situation at the plant, and evaluated different means that appear effective in improving the efficiency, including the gas turbine absorbed air cooling system, the steam injection system, and the combined cycle. As a result of the discussions, it was revealed that energy saving effect can be obtained at 145 TJ with the gas turbine absorbed air cooling system, 224 TJ with the steam injection system, and 1017 TJ with the combined cycle. The annual reduction of greenhouse gas emission due to the above energy conservation would be about 11 thousand tons, 16.5 thousand tons, and 75 thousand tons, respectively. However, the investment payback period would be about 2.45 years, 8.31 years, and 14.21 years, respectively. Therefore, the profitability does not appear very attractive because of low fuel unit cost. (NEDO)

The condition monitoring system of turbine system components for nuclear power plants

International Nuclear Information System (INIS)

Ono, Shigetoshi

2013-01-01

The thermal and nuclear power plants have been imposed a stable supply of electricity. To certainly achieve this, we built the plant condition monitoring system based on the heat and mass balance calculation. If there are some performance changes on the turbine system components of their power plants, the heat and mass balance of the turbine system will change. This system has ability to detect the abnormal signs of their components by finding the changes of the heat and mass balance. Moreover we note that this system is built for steam turbine cycle operating with saturated steam conditions. (author)

Miniature Gas-Turbine Power Generator

Science.gov (United States)

Wiberg, Dean; Vargo, Stephen; White, Victor; Shcheglov, Kirill

2003-01-01

A proposed microelectromechanical system (MEMS) containing a closed- Brayton-cycle turbine would serve as a prototype of electric-power generators for special applications in which high energy densities are required and in which, heretofore, batteries have been used. The system would have a volume of about 6 cm3 and would operate with a thermal efficiency >30 percent, generating up to 50 W of electrical power. The energy density of the proposed system would be about 10 times that of the best battery-based systems now available, and, as such, would be comparable to that of a fuel cell. The working gas for the turbine would be Xe containing small quantities of CO2, O2, and H2O as gaseous lubricants. The gas would be contained in an enclosed circulation system, within which the pressure would typically range between 5 and 50 atm (between 0.5 and 5 MPa). The heat for the Brayton cycle could be supplied by any of a number of sources, including a solar concentrator or a combustor burning a hydrocarbon or other fuel. The system would include novel heat-transfer and heat-management components. The turbine would be connected to an electric power generator/starter motor. The system would include a main rotor shaft with gas bearings; the bearing surfaces would be made of a ceramic material coated with nanocrystalline diamond. The shaft could withstand speed of 400,000 rpm or perhaps more, with bearing-wear rates less than 10(exp -)4 those of silicon bearings and 0.05 to 0.1 those of SiC bearings, and with a coefficient of friction about 0.1 that of Si or SiC bearings. The components of the system would be fabricated by a combination of (1) three-dimensional xray lithography and (2) highly precise injection molding of diamond-compatible metals and ceramic materials. The materials and fabrication techniques would be suitable for mass production. The disadvantages of the proposed system are that unlike a battery-based system, it could generate a perceptible amount of sound, and

Hybrid solar central receiver for combined cycle power plant

Science.gov (United States)

Bharathan, Desikan; Bohn, Mark S.; Williams, Thomas A.

1995-01-01

A hybrid combined cycle power plant including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production.

Thermodynamic analysis of a combined gas turbine, ORC cycle and absorption refrigeration for a CCHP system

International Nuclear Information System (INIS)

Mohammadi, Amin; Kasaeian, Alibakhsh; Pourfayaz, Fathollah; Ahmadi, Mohammad Hossein

2017-01-01

Highlights: • Thermodynamic analysis of a hybrid CCHP system. • Sensitivity analysis is performed on the most important parameters of the system. • Pressure ratio and gas turbine inlet temperature are the most effective parameters. - Abstract: Hybrid power systems are gained more attention due to their better performance and higher efficiency. Widespread use of these systems improves environmental situation as they reduce the amount of fossil fuel consumption. In this paper a hybrid system composed of a gas turbine, an ORC cycle and an absorption refrigeration cycle is proposed as a combined cooling, heating and power system for residential usage. Thermodynamic analysis is applied on the system. Also a parametric analysis is carried out to investigate the effect of different parameters on the system performance and output cooling, heating and power. The results show that under design conditions, the proposed plant can produce 30 kW power, 8 kW cooling and almost 7.2 ton hot water with an efficiency of 67.6%. Moreover, parametric analysis shows that pressure ratio and gas turbine inlet temperature are the most important and influential parameters. After these two, ORC turbine inlet temperature is the most effective parameter as it can change both net output power and energy efficiency of the system.

Parametric studies on different gas turbine cycles for a high temperature gas-cooled reactor

International Nuclear Information System (INIS)

Wang Jie; Gu Yihua

2005-01-01

The high temperature gas-cooled reactor (HTGR) coupled with turbine cycle is considered as one of the leading candidates for future nuclear power plants. In this paper, the various types of HTGR gas turbine cycles are concluded as three typical cycles of direct cycle, closed indirect cycle and open indirect cycle. Furthermore they are theoretically converted to three Brayton cycles of helium, nitrogen and air. Those three types of Brayton cycles are thermodynamically analyzed and optimized. The results show that the variety of gas affects the cycle pressure ratio more significantly than other cycle parameters, however, the optimized cycle efficiencies of the three Brayton cycles are almost the same. In addition, the turbomachines which are required for the three optimized Brayton cycles are aerodynamically analyzed and compared and their fundamental characteristics are obtained. Helium turbocompressor has lower stage pressure ratio and more stage number than those for nitrogen and air machines, while helium and nitrogen turbocompressors have shorter blade length than that for air machine

Cogenerative Performance of a Wind − Gas Turbine − Organic Rankine Cycle Integrated System for Offshore Applications

DEFF Research Database (Denmark)

Bianchi, Michele; Branchini, Lisa; De Pascale, Andrea

2016-01-01

Gas Turbines (GT) are widely used for power generationin offshore oil and gas facilities, due to their high reliability,compactness and dynamic response capabilities. Small heavyduty and aeroderivative units in multiple arrangements aretypically used to offer larger load flexibility......, but limitedefficiency of such machines is the main drawback. A solutionto enhance the system performance, also in Combined Heat andPower (CHP) arrangement, is the implementation of OrganicRankine Cycle (ORC) systems at the bottom of the gas turbines.Moreover, the resulting GT-ORC combined cycle could befurther...... a 10MW offshorewind farm and three gas turbines rated for 16:5MW, eachone coupled with an 4:5MW ORC module. The ORC mainparameters are observed under different wind power fluctuations.Due to the non-programmable availability of wind and powerdemand, the part-load and dynamic characteristics...

A genetic algorithm applied to a PWR turbine extraction optimization to increase cycle efficiency

International Nuclear Information System (INIS)

Sacco, Wagner F.; Schirru, Roberto

2002-01-01

In nuclear power plants feedwater heaters are used to heat feedwater from its temperature leaving the condenser to final feedwater temperature using steam extracted from various stages of the turbines. The purpose of this process is to increase cycle efficiency. The determination of the optimal fraction of mass flow rate to be extracted from each stage of the turbines is a complex optimization problem. This kind of problem has been efficiently solved by means of evolutionary computation techniques, such as Genetic Algorithms (GAs). GAs, which are systems based upon principles from biological genetics, have been successfully applied to several combinatorial optimization problems in nuclear engineering, as the nuclear fuel reload optimization problem. We introduce the use of GAs in cycle efficiency optimization by finding an optimal combination of turbine extractions. In order to demonstrate the effectiveness of our approach, we have chosen a typical PWR as case study. The secondary side of the PWR was simulated using PEPSE, which is a modeling tool used to perform integrated heat balances for power plants. The results indicate that the GA is a quite promising tool for cycle efficiency optimization. (author)

Combined cycle power plant with integrated low temperature heat (LOTHECO)

International Nuclear Information System (INIS)

Kakaras, E.; Doukelis, A.; Leithner, R.; Aronis, N.

2004-01-01

The major driver to enhance the efficiency of the simple gas turbine cycle has been the increase in process conditions through advancements in materials and cooling methods. Thermodynamic cycle developments or cycle integration are among the possible ways to further enhance performance. The current paper presents the possibilities and advantages from the LOTHECO natural gas-fired combined cycle concept. In the LOTHECO cycle, low-temperature waste heat or solar heat is used for the evaporation of injected water droplets in the compressed air entering the gas turbine's combustion chamber. Following a description of this innovative cycle, its advantages are demonstrated by comparison between different gas turbine power generation systems for small and large-scale applications, including thermodynamic and economic analysis. A commercial gas turbine (ALSTOM GT10C) has been selected and computed with the heat mass balance program ENBIPRO. The results from the energy analysis are presented and the features of each concept are discussed. In addition, the exergy analysis provides information on the irreversibilities of each process and suggested improvements. Finally, the economic analysis reveals that the combined cycle plant with a heavy-duty gas turbine is the most efficient and economic way to produce electricity at base load. However, on a smaller scale, innovative designs, such as the LOTHECO concept, are required to reach the same level of performance at feasible costs

Feasibility of Ericsson type isothermal expansion/compression gas turbine cycle for nuclear energy use

International Nuclear Information System (INIS)

Shimizu, Akihiko

2007-01-01

A gas turbine with potential demand for the next generation nuclear energy use such as HTGR power plants, a gas cooled FBR, a gas cooled nuclear fusion reactor uses helium as working gas and with a closed cycle. Materials constituting a cycle must be set lower than allowable temperature in terms of mechanical strength and radioactivity containment performance and so expansion inlet temperature is remarkably limited. For thermal efficiency improvement, isothermal expansion/isothermal compression Ericsson type gas turbine cycle should be developed using wet surface of an expansion/compressor casing and a duct between stators without depending on an outside heat exchanger performing multistage re-heat/multistage intermediate cooling. Feasibility of an Ericsson cycle in comparison with a Brayton cycle and multi-stage compression/expansion cycle was studied and technologies to be developed were clarified. (author)

Fiscal 1981 Sunshine Project research report. Development of hydrothermal power plant. Development of binary cycle power plant (Research on heat cycle and heat medium, materials, and heat medium turbine); 1981 nendo nessui riyo hatsuden plant no kaihatsu seika hokokusho. Binary cycle hatsuden plant no kaihatsu (netsu cycle oyobi netsubaitai no kenkyu, zairyo no kenkyu narasbini netsubaitai turbine no kenkyu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1982-03-01

This report summarizes the final fiscal 1981 research result on components of the next 10MW class geothermal binary cycle power plant. In the research on heat cycle and heat medium, R-C318 and R-124 were excellent in output characteristics in a low-temperature zone and high-temperature zone in a hot water temperature range of 120-160 degreesC, respectively, however, at present R-114 was most reasonable from the viewpoint of heat medium price and supply system. In the research on martials, study was made on inlet-attack and stress corrosion of heat exchanger pipes of 18Cr-13Ni-2Mo steel, and combination use of inexpensive materials (carbon steel). As used giving attention to stress corrosion, at present 18Cr-13Ni-2Mo steel was most suitable material, while clad carbon steel was also usable. In the research on heat medium turbine, the 1000-hour durability test result of mechanical seal showed that mechanical seal is best for heat medium turbines. (NEDO)

The impact of the new investments in combined cycle gas turbine power plants on the Italian electricity price

International Nuclear Information System (INIS)

Fontini, Fulvio; Paloscia, Lorenzo

2007-01-01

The paper measures the variation of the electricity price in Italy within the next 10 years due to the recent investment flow in combined cycle gas turbine (CCGT) power plants. It starts by investigating the possibility of decoupling gas and oil prices on the basis of hypotheses about the amount of existing resources and plausible technical substitutability assumptions of the latter with the former. In particular, it is supposed that, in the Italian market, natural gas will play a crucial role which oil has had in power generation. The price of electricity stemming from natural gas is then calculated taking into account the role of the power mix restructuring that derives from the CCGT power plants investments. Under reasonable assumptions, it is shown that a net reduction of at least 17% on the electric price is likely to be expected. (author)

Steam turbines for the future

International Nuclear Information System (INIS)

Trassl, W.

1988-01-01

Approximately 75% of the electrical energy produced in the world is generated in power plants with steam turbines (fossil and nuclear). Although gas turbines are increasingly applied in combined cycle power plants, not much will change in this matter in the future. As far as the steam parameters and the maximum unit output are concerned, a certain consolidation was noted during the past decades. The standard of development and mathematical penetration of the various steam turbine components is very high today and is applied in the entire field: For saturated steam turbines in nuclear power plants and for steam turbines without reheat, with reheat and with double reheat in fossil-fired power plants and for steam turbines with and without reheat in combined cycle power plants. (orig.) [de

A combined power cycle utilizing low-temperature waste heat and LNG cold energy

International Nuclear Information System (INIS)

Shi Xiaojun; Che Defu

2009-01-01

This paper has proposed a combined power system, in which low-temperature waste heat can be efficiently recovered and cold energy of liquefied natural gas (LNG) can be fully utilized as well. This system consists of an ammonia-water mixture Rankine cycle and an LNG power generation cycle, and it is modelled by considering mass, energy and species balances for every component and thermodynamic analyses are conducted. The results show that the proposed combined cycle has good performance, with net electrical efficiency and exergy efficiency of 33% and 48%, respectively, for a typical operating condition. The power output is equal to 1.25 MWh per kg of ammonia-water mixture. About 0.2 MW of electrical power for operating sea water pumps can be saved. Parametric analyses are performed for the proposed combined cycle to evaluate the effects of key factors on the performance of the proposed combined cycle through simulation calculations. Results show that a maximum net electrical efficiency can be obtained as the inlet pressure of ammonia turbine increases and the peak value increases as the ammonia mass fraction increases. Exergy efficiency goes up with the increased ammonia turbine inlet pressure. With the ammonia mass fraction increases, the net electrical efficiency increases, whereas exergy efficiency decreases. For increasing LNG turbine inlet pressure or heat source temperature, there is also a peak of net electrical efficiency and exergy efficiency. With the increase of LNG gas turbine outlet pressure, exergy efficiency increases while net electrical efficiency drops

High Power Density Power Electronic Converters for Large Wind Turbines

DEFF Research Database (Denmark)

Senturk, Osman Selcuk

. For these VSCs, high power density is required due to limited turbine nacelle space. Also, high reliability is required since maintenance cost of these remotely located wind turbines is quite high and these turbines operate under harsh operating conditions. In order to select a high power density and reliability......In large wind turbines (in MW and multi-MW ranges), which are extensively utilized in wind power plants, full-scale medium voltage (MV) multi-level (ML) voltage source converters (VSCs) are being more preferably employed nowadays for interfacing these wind turbines with electricity grids...... VSC solution for wind turbines, first, the VSC topology and the switch technology to be employed should be specified such that the highest possible power density and reliability are to be attained. Then, this qualitative approach should be complemented with the power density and reliability...

Closed Cycle Engine Program Used in Solar Dynamic Power Testing Effort

Science.gov (United States)

Ensworth, Clint B., III; McKissock, David B.

1998-01-01

NASA Lewis Research Center is testing the world's first integrated solar dynamic power system in a simulated space environment. This system converts solar thermal energy into electrical energy by using a closed-cycle gas turbine and alternator. A NASA-developed analysis code called the Closed Cycle Engine Program (CCEP) has been used for both pretest predictions and post-test analysis of system performance. The solar dynamic power system has a reflective concentrator that focuses solar thermal energy into a cavity receiver. The receiver is a heat exchanger that transfers the thermal power to a working fluid, an inert gas mixture of helium and xenon. The receiver also uses a phase-change material to store the thermal energy so that the system can continue producing power when there is no solar input power, such as when an Earth-orbiting satellite is in eclipse. The system uses a recuperated closed Brayton cycle to convert thermal power to mechanical power. Heated gas from the receiver expands through a turbine that turns an alternator and a compressor. The system also includes a gas cooler and a radiator, which reject waste cycle heat, and a recuperator, a gas-to-gas heat exchanger that improves cycle efficiency by recovering thermal energy.

Exergy and Environmental Impact Assessment between Solar Powered Gas Turbine and Conventional Gas Turbine Power Plant

Directory of Open Access Journals (Sweden)

Ali Rajaei

2016-01-01

Full Text Available Recuperator is a heat exchanger that is used in gas turbine power plants to recover energy from outlet hot gases to heat up the air entering the combustion chamber. Similarly, the combustion chamber inlet air can be heated up to temperatures up to 1000 (°C by solar power tower (SPT as a renewable and environmentally benign energy source. In this study, comprehensive comparison between these two systems in terms of energy, exergy, and environmental impacts is carried out. Thermodynamic simulation of both cycles is conducted using a developed program in MATLAB environment. Exergetic performances of both cycles and their emissions are compared and parametric study is carried out. A new parameter (renewable factor is proposed to evaluate resources quality and measure how green an exergy loss or destruction or a system as a whole is. Nonrenewable exergy destruction and loss are reduced compared to GT with recuperator cycle by 34.89% and 47.41%, respectively. Reductions in CO2, NOx, and CO compared to GT with recuperator cycle by 49.92%, 66.14%, and 39.77%, respectively, are in line with renewable factor value of around 55.7 which proves the ability of the proposed green measure to evaluate and compare the cycles performances.

Application of the Combined Cycle LWR-Gas Turbine to PWR for NPP Life Extension Safety Upgrade and Improving Economy

International Nuclear Information System (INIS)

Kuznetsov, Yu. N.

2006-01-01

Currently, some of the most important problem for the nuclear industry are life extension, advance competitiveness and safety of aging LWR NPPs. Based on results of studies performed in the USA (Battelle Memorial Institute) and in Russia (NIKIET), a new power technology, using a combined cycle gas-turbine facility CCGT - LWR, so called TD-Cycle, can significantly help in resolution of some problems of nuclear power industry. The nuclear steam and gas topping cycle is used for re-powering a light water pressurized reactor of PWR or VVER type. An existing NPP is topped with a gas turbine facility with a heat recovery steam generator (HRSG) generating steam from waste heat. The superheated steam of high pressure (P=90-165 bar, T=500-550 C) generated in the HRSG, is expanded in a high pressure (HP) turbine for producing electricity. The HP turbine can work on one shaft with the the gas turbine or at one shaft with intermediate (IP) or low (LP) pressure parts of the main nuclear steam turbine, or with a separate electric generator. The exhausted steam from the HP turbine is injected into the steam mixer where it is mixed with the saturated steam from the NPP steam generator (SG). The mixer is intended to superheat the main nuclear steam and should be characterized by minimum losses during mixing superheated and saturated steam. Steam from the mixer superheated by 20-60 C directs to the existing IP turbine, and then, through a separator-reheater flows into the LP turbine. Feed water re-heaters of LP and HP are actually unchanged in this case. Feed water extraction to the HRSG is supplied after one of LP water heaters. This proposal is intended to re-power existing LWR NPPs. To minimize cost, the IP and LP turbines and electric generator would remain the same. The reactor thermal power and fast neutron flux to the reactor vessel would decrease by 30-50 percent of nominal values. The external peripheral row of fuel elements can be replaced with metal absorber rods to

Combined cycle power plants: technological prospects for improving the efficiency

International Nuclear Information System (INIS)

Lauri, R.

2009-01-01

The combined cycle power plants characteristics are better than one course open to a closed loop presenting an electrical efficiency close to 60% do not reach for gas turbine engines for power plants and conventional steam engines. [it

Integration of A Solid Oxide Fuel Cell into A 10 MW Gas Turbine Power Plant

Directory of Open Access Journals (Sweden)

Denver F. Cheddie

2010-04-01

Full Text Available Power generation using gas turbine power plants operating on the Brayton cycle suffers from low efficiencies. In this work, a solid oxide fuel cell (SOFC is proposed for integration into a 10 MW gas turbine power plant, operating at 30% efficiency. The SOFC system utilizes four heat exchangers for heat recovery from both the turbine outlet and the fuel cell outlet to ensure a sufficiently high SOFC temperature. The power output of the hybrid plant is 37 MW at 66.2% efficiency. A thermo-economic model predicts a payback period of less than four years, based on future projected SOFC cost estimates.

High performance integrated solar combined cycles with minimum modifications to the combined cycle power plant design

International Nuclear Information System (INIS)

Manente, Giovanni

2016-01-01

Highlights: • Off-design model of a 390 MW_e three pressure combined cycle developed and validated. • The off-design model is used to evaluate different hybridization schemes with solar. • Power boosting and fuel saving with different design modifications are considered. • Maximum solar share of total electricity is only 1% with the existing equipment. • The maximum incremental solar radiation-to-electrical efficiency approaches 29%. - Abstract: The integration of solar energy into natural gas combined cycles has been successfully demonstrated in several integrated solar combined cycles since the beginning of this decade in many countries. There are many motivations that drive investments on integrated solar combined cycles which are primarily the repowering of existing power plants, the compliance with more severe environmental laws on emissions and the mitigation of risks associated with large solar projects. Integrated solar combined cycles are usually developed as brownfield facilities by retrofitting existing natural gas combined cycles and keeping the existing equipment to minimize costs. In this work a detailed off-design model of a 390 MW_e three pressure level natural gas combined cycle is built to evaluate different integration schemes of solar energy which either keep the equipment of the combined cycle unchanged or include new equipment (steam turbine, heat recovery steam generator). Both power boosting and fuel saving operation strategies are analyzed in the search for the highest annual efficiency and solar share. Results show that the maximum incremental power output from solar at design solar irradiance is limited to 19 MW_e without modifications to the existing equipment. Higher values are attainable only including a larger steam turbine. High solar radiation-to-electrical efficiencies in the range 24–29% can be achieved in the integrated solar combined cycle depending on solar share and extension of tube banks in the heat recovery

Combined cycle versus one thousand diesel power plants: pollutant emissions, ecological efficiency and economic analysis

International Nuclear Information System (INIS)

Silveira, Jose Luz; de Carvalho, Joao Andrade; de Castro Villela, Iraides Aparecida

2007-01-01

The increase in the use of natural gas in Brazil has stimulated public and private sectors to analyse the possibility of using combined cycle systems for generation of electrical energy. Gas turbine combined cycle power plants are becoming increasingly common due to their high efficiency, short lead times, and ability to meet environmental standards. Power is produced in a generator linked directly to the gas turbine. The gas turbine exhaust gases are sent to a heat recovery steam generator to produce superheated steam that can be used in a steam turbine to produce additional power. In this paper a comparative study between a 1000 MW combined cycle power plant and 1000kW diesel power plant is presented. In first step, the energetic situation in Brazil, the needs of the electric sector modification and the needs of demand management and integrated means planning are clarified. In another step the characteristics of large and small thermoelectric power plants that use natural gas and diesel fuel, respectively, are presented. The ecological efficiency levels of each type of power plant is considered in the discussion, presenting the emissions of particulate material, sulphur dioxide (SO 2 ), carbon dioxide (CO 2 ) and nitrogen oxides (NO x ). (author)

Exergetic optimization of the part-flow evaporative gas turbine cycles. Paper no. IGEC-1-ID23

International Nuclear Information System (INIS)

Yari, M.; Sarabch, K.

2005-01-01

The evaporative gas turbine cycle is a new high efficiency power cycle that has reached the pilot plant testing stage. The latest configuration proposed for this cycle is known as part flow evaporative gas turbine cycle (PEvGT) in which humidification is combined with steam injection. Having advantages of both steam injected and humid air cycles, it is regarded as a very desirable plant for future. In this paper the exergy equations have been added to the mathematical model. Then exergy analysis and optimization of the PEvGT cycles: PEvGT and PEvGT-IC have been done. This study show that the maximum exergy destruction rate related to combustion chamber in both cycles. The exergetic optimization shows, the maximum first and second efficiency occur in the highest values of part-flow humidification rate. (author)

GESIT: a thermodynamic program for single cycle gas turbine plants with and without intercoolers

Energy Technology Data Exchange (ETDEWEB)

Heil, J

1973-08-01

A computer program for the thermodynamic modeling of singlecycle gas turbine plants is described. A high-temperature reactor is assumed as a heat source in the program, but the HTR can be replaced with another heat source without difficulty. Starting from a set of independent data, the program calculates efficiencies and mass flows. It indicates all values for a heat and power balance and prints out the temperatures and pressures for the different parts of the cycle. Besides this, the program is able to optimize the compression ratios for minimal power input. It also takes into account turbine rotor cooling (at the roots of the blades). Furthermore, the program is able to use either total pressure loss or specified losses in different parts of the cycle. The program GESlT can also handle systems with one or two intercoolers, or with no intercooler. GESIT gives all input and output values for the heat exchangers and turbo-machines. First the single-cycle gas turbine plant is described. After that the computational basis for the program and the program structure is explained. Instructions for data input are given so that the program can be immediately utilized. An example of input data together with the associated output is presented. (auth)

Performance Comparison on Repowering of a Steam Power Plant with Gas Turbines and Solid Oxide Fuel Cells

DEFF Research Database (Denmark)

Rokni, Masoud

2016-01-01

Repowering is a process for transforming an old power plant for greater capacity and/or higher efficiency. As a consequence, the repowered plant is characterized by higher power output and less specific CO2 emissions. Usually, repowering is performed by adding one or more gas turbines into an exi......Repowering is a process for transforming an old power plant for greater capacity and/or higher efficiency. As a consequence, the repowered plant is characterized by higher power output and less specific CO2 emissions. Usually, repowering is performed by adding one or more gas turbines...... into an existing steam cycle which was built decades ago. Thus, traditional repowering results in combined cycles (CC). High temperature fuel cells (such as solid oxide fuel cell (SOFC)) could also be used as a topping cycle, achieving even higher global plant efficiency and even lower specific CO2 emissions....... Decreasing the operating temperature in a SOFC allows the use of less complex materials and construction methods, consequently reducing plant and the electricity costs. A lower working temperature makes it also suitable for topping an existing steam cycle, instead of gas turbines. This is also the target...

Life cycle evaluation of an intercooled gas turbine plant used in conjunction with renewable energy

Directory of Open Access Journals (Sweden)

Thank-God Isaiah

2016-09-01

Full Text Available The life cycle estimation of power plants is important for gas turbine operators. With the introduction of wind energy into the grid, gas turbine operators now operate their plants in Load–Following modes as back-ups to the renewable energy sources which include wind, solar, etc. The motive behind this study is to look at how much life is consumed when an intercooled power plant with 100 MW power output is used in conjunction with wind energy. This operation causes fluctuations because the wind energy is unpredictable and overtime causes adverse effects on the life of the plant – The High Pressure Turbine Blades. Such fluctuations give rise to low cycle fatigue and creep failure of the blades depending on the operating regime used. A performance based model that is capable of estimating the life consumed of an intercooled power plant has been developed. The model has the capability of estimating the life consumed based on seasonal power demands and operations. An in-depth comparison was undertaken on the life consumed during the seasons of operation and arrives at the conclusion that during summer, the creep and low cycle life is consumed higher than the rest periods. A comparison was also made to determine the life consumed between Load–Following and stop/start operating scenarios. It was also observed that daily creep life consumption in summer was higher than the winter period in-spite of having lower average daily operating hours in a Start–Stop operating scenario.

An optimal tuning strategy for tidal turbines.

Science.gov (United States)

Vennell, Ross

2016-11-01

Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This 'impatient-tuning strategy' results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing 'patient-tuning strategy' which maximizes the power output averaged over the tidal cycle. This paper presents a 'smart patient tuning strategy', which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine's average power output.

Gas turbine cooling modeling - Thermodynamic analysis and cycle simulations

Energy Technology Data Exchange (ETDEWEB)

Jordal, Kristin

1999-02-01

Considering that blade and vane cooling are a vital point in the studies of modern gas turbines, there are many ways to include cooling in gas turbine models. Thermodynamic methods for doing this are reviewed in this report, and, based on some of these methods, a number of model requirements are set up and a Cooled Gas Turbine Model (CGTM) for design-point calculations of cooled gas turbines is established. Thereafter, it is shown that it is possible to simulate existing gas turbines with the CGTM. Knowledge of at least one temperature in the hot part of the turbine (TET, TRIT or possibly TIT) is found to be vital for a complete heat balance over the turbine. The losses, which are caused by the mixing of coolant and main flow, are in the CGTM considered through a polytropic efficiency reduction factor S. Through the study of S, it can be demonstrated that there is more to gain from coolant reduction in a small and/or old turbine with poor aerodynamics, than there is to gain in a large, modern turbine, where the losses due to interaction between coolant and main flow are, relatively speaking, small. It is demonstrated, at the design point (TET=1360 deg C, {pi}=20) for the simple-cycle gas turbine, that heat exchanging between coolant and fuel proves to have a large positive impact on cycle efficiency, with an increase of 0.9 percentage points if all of the coolant passes through the heat exchanger. The corresponding improvement for humidified coolant is 0.8 percentage points. A design-point study for the HAT cycle shows that if all of the coolant is extracted after the humidification tower, there is a decrease in coolant requirements of 7.16 percentage points, from 19.58% to 12.52% of the compressed air, and an increase in thermal efficiency of 0.46 percentage points, from 53.46% to 53.92%. Furthermore, it is demonstrated with a TET-parameter variation, that the cooling of a simple-cycle gas turbine with humid air can have a positive effect on thermal efficiency

Comparative life-cycle assessment of a small wind turbine for residential off-grid use

International Nuclear Information System (INIS)

Fleck, Brian; Huot, Marc

2009-01-01

As the popularity of renewable energy systems grows, small wind turbines are becoming a common choice for off-grid household power. However, the true benefits of such systems over the traditional internal combustion systems are unclear. This study employs a life-cycle assessment methodology in order to directly compare the environmental impacts, net-energy inputs, and life-cycle cost of two systems: a stand-alone small wind turbine system and a single-home diesel generator system. The primary focus for the investigation is the emission of greenhouse gases (GHG) including CO 2 , CH 4 , and N 2 O. These emissions are calculated over the life-cycle of the two systems which provide the same amount of energy to a small off-grid home over a twenty-year period. The results show a considerable environmental benefit for small-scale wind power. The wind generator system offered a 93% reduction of GHG emissions when compared to the diesel system. Furthermore, the diesel generator net-energy input was over 200 MW, while the wind system produced an electrical energy output greater than its net-energy input. Economically, the conclusions were less clear. The assumption was made that diesel fuel cost over the next twenty years was based on May 2008 prices, increasing only in proportion to inflation. As such, the net-present cost of the wind turbine system was 14% greater than the diesel system. However, a larger model wind turbine would likely benefit from the effects of the 'economy of scale,' producing superior results both economically and environmentally. (author)

Two 850 MW turbines on daily cycling, design and operating experience

Energy Technology Data Exchange (ETDEWEB)

Stodieck, W; Straetz, A [Maschinenfabrik Augsburg-Nuernberg (M.A.N.) A.G., Nuernberg (Germany, F.R.)

1979-02-01

When Pennsylvania Power and Light Company (PPandL) of Allentown, U.S.A. signed a contract in 1970 with M.A.N. for the supply of two 850 MW turbines as part of extension of its existing coal-fired power station at Martins Creek by two oil-fired units, continuous base load operation was planned for the initial years. After about ten years both units should have been curbed to low load operation at night and completely shutdown at weekends. Then in 1973 when the oil crisis led to fuel prices which proved the operation of both units uneconomic the way they were planned for the initial years, all conditions were given to operate both turbines on a daily cycling basis from their commissioning day on. This was due to the installation of quality equipment for the improvement of thermal performance.

Transcritical CO2 power cycle – Effects of regenerative heating using turbine bleed gas at intermediate pressure

International Nuclear Information System (INIS)

Mondal, Subha; De, Sudipta

2015-01-01

For energy utilization from low temperature waste heat, CO 2 is a potential working fluid due to its lower critical temperature. In this work, assuming finite quantity of flue gas available at low temperature (200 °C), a thermodynamic model is developed for a transcritical CO 2 power cycle utilizing turbine bleed gas for regenerative heating. Analysis show that the cycle performance improves with higher value of bleed ratio. However, for a specified bleed pressure and bleed gas temperature at the regenerator exit, maximum practical value of bleed ratio may be fixed by considering the exponential growth of the regenerator size (specified by NTU (number of transfer unit)). Most significant observation is the existence of optimum bleed pressures corresponding to maximum 1st law efficiency or minimum cycle irreversibility for specified values of remaining cycle parameters. - Highlights: • Thermodynamic model for Transcritical CO 2 cycle with bleed gas are developed. • Effects of bleed ratio, pressure, and regenerator exit gas temperature are studied. • 1st and 2nd law efficiencies are estimated. • An optimum bleed pressure for maximum 1st and 2nd efficiencies is obtained. • Maximum value of 1st law efficiency is limited by regenerator size

Predictive control strategy of a gas turbine for improvement of combined cycle power plant dynamic performance and efficiency.

Science.gov (United States)

Mohamed, Omar; Wang, Jihong; Khalil, Ashraf; Limhabrash, Marwan

2016-01-01

This paper presents a novel strategy for implementing model predictive control (MPC) to a large gas turbine power plant as a part of our research progress in order to improve plant thermal efficiency and load-frequency control performance. A generalized state space model for a large gas turbine covering the whole steady operational range is designed according to subspace identification method with closed loop data as input to the identification algorithm. Then the model is used in developing a MPC and integrated into the plant existing control strategy. The strategy principle is based on feeding the reference signals of the pilot valve, natural gas valve, and the compressor pressure ratio controller with the optimized decisions given by the MPC instead of direct application of the control signals. If the set points for the compressor controller and turbine valves are sent in a timely manner, there will be more kinetic energy in the plant to release faster responses on the output and the overall system efficiency is improved. Simulation results have illustrated the feasibility of the proposed application that has achieved significant improvement in the frequency variations and load following capability which are also translated to be improvements in the overall combined cycle thermal efficiency of around 1.1 % compared to the existing one.

Modelling and exergoeconomic-environmental analysis of combined cycle power generation system using flameless burner for steam generation

International Nuclear Information System (INIS)

Hosseini, Seyed Ehsan; Barzegaravval, Hasan; Ganjehkaviri, Abdolsaeid; Wahid, Mazlan Abdul; Mohd Jaafar, M.N.

2017-01-01

Highlights: • Using flameless burner as a supplementary firing system after gas turbine is modeled. • Thermodynamic, economic and environmental analyses of this model are performed. • Efficiency of the plant increases about 6% and CO_2 emission decreases up to 5.63% in this design. • Available exergy for work production in both gas cycle and steam cycle increases in this model. - Abstract: To have an optimum condition for the performance of a combined cycle power generation, using supplementary firing system after gas turbine was investigated by various researchers. Since the temperature of turbine exhaust is higher than auto-ignition temperature of the fuel in optimum condition, using flameless burner is modelled in this paper. Flameless burner is installed between gas turbine cycle and Rankine cycle of a combined cycle power plant which one end is connected to the outlet of gas turbine (as primary combustion oxidizer) and the other end opened to the heat recovery steam generator. Then, the exergoeconomic-environmental analysis of the proposed model is evaluated. Results demonstrate that efficiency of the combined cycle power plant increases about 6% and CO_2 emission reduces up to 5.63% in this proposed model. It is found that the variation in the cost is less than 1% due to the fact that a cost constraint is implemented to be equal or lower than the design point cost. Moreover, exergy of flow gases increases in all points except in heat recovery steam generator. Hence, available exergy for work production in both gas cycle and steam cycle will increase in new model.

Direct FuelCell/Turbine Power Plant

Energy Technology Data Exchange (ETDEWEB)

Hossein Ghezel-Ayagh

2008-09-30

This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power cycling of the system, were investigated. A subsequent series of tests included operation of the sub-MW Direct FuelCell/Turbine power plant with a Capstone C60 microturbine. The C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in initial tests using the 30kW microturbine. The proof-of-concept test results confirmed the stability and controllability of operating a fullsize (250 kW) fuel cell stack in combination with a microturbine. Thermal management of the system was confirmed and power plant operation, using the microturbine as the only source of fresh air supply

Modeling of wind turbines for power system studies

Energy Technology Data Exchange (ETDEWEB)

Petru, T.

2001-05-01

When wind turbines are installed into the electric grid, the power quality is affected. Today, strict installation recommendations often prevail due to a lack of knowledge on this subject. Consequently, it is important to predict the impact of wind turbines on the electric grid before the turbines are installed. The thesis describes relevant power quality issues, discusses different configurations of wind turbines with respect to power quality and draw requirements regarding wind turbine modeling. A model of a stall-regulated, fixed-speed wind turbine system is introduced and its power quality impact on the electric grid is evaluated. The model is verified with field measurements.

Economic evaluation of externally fired gas turbine cycles for small-scale biomass cogeneration

Energy Technology Data Exchange (ETDEWEB)

Anheden, Marie [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

2001-01-01

In this conceptual study, externally fired gas turbine (EFGT) cycles in combination with a biomass-fueled, atmospheric circulating fluidized bed (CFB) furnace are investigated for small scale heat and power production ({approx} 8 MW fuel input). Three cycle configurations are considered: closed cycle, with nitrogen, helium, and a helium/carbon dioxide mixture as working fluids; open cycle operating in parallel to the CFB system; and open cycle with a series connection to the CFB system. Intercooling, postcooling, and recuperation are employed with the goal of maximizing efficiency. Aside from a thermodynamic performance analysis, the study includes an economic analysis of both the closed and open externally fired gas turbine configurations, and comparisons are made with existing and emerging alternatives for small-scale biomass cogeneration. Simulation results show that thermodynamic performance varies slightly between the different configurations and working fluids, with electrical efficiencies of 31-38% (LHV) and total efficiency of 85-106% (LHV). The economic evaluation shows that the turbomachinery and the CFB furnace dominate the total plant cost, with each contributing about 1/3 of the total installed equipment cost. The specific capital cost for installation in Sweden in 1998 currency is calculated as 26-31 kSEK/kW{sub e} which is equivalent to 3 200-3 900 USD/kW{sub e} or 2 700-3 300 EUR/kW{sub e} .The cost of electricity, COE, is estimated to 590-670 SEK/MWh{sub e} (equivalent to 73-84 USD/MWh{sub e} or 62-71 EUR/MWh{sub e}) for 4 000 full load hours per year in a cogeneration application. Comparing the economic results for the externally fired gas turbine cycles in a slightly larger scale (40-50 MW{sub f}) to the economics of conventional biomass fired steam turbine cycles shows that the cost of electricity for the two plant configurations are roughly the same with a COE of 300-350 SEK/MWh{sub e}. It is believed that the economic performance of the EFGT

Life cycle assessment of a multi-megawatt wind turbine

Energy Technology Data Exchange (ETDEWEB)

Martinez, E.; Pellegrini, S. [Grupo Eolicas Riojanas, R and D Division, Carretera de Laguardia, 91-93, 26006 Logrono, La Rioja (Spain); Sanz, F.; Blanco, J. [Department of Mechanical Engineering, University of La Rioja, Logrono, La Rioja (Spain); Jimenez, E. [Department of Electrical Engineering, University of La Rioja, Logrono, La Rioja (Spain)

2009-03-15

At the present moment in time, renewable energy sources have achieved great significance for modern day society. The main reason for this boom is the need to use alternative sources of energy to fossil fuels which are free of CO{sub 2} emissions and contamination. Among the current renewable energy sources, the growth of wind farms has been spectacular. Wind power uses the kinetic energy of the wind to produce a clean form of energy without producing contamination or emissions. The problem it raises is that of quantifying to what extent it is a totally clean form of energy. In this sense we have to consider not only the emissions produced while they are in operation, but also the contamination and environmental impact resulting from their manufacture and the future dismantling of the turbines when they come to the end of their working life. The aim of this study is to analyse the real impact that this technology has if we consider the whole life cycle. The application of the ISO 14040 standard [ISO. ISO 14040. Environmental management - life cycle assessment - principles and framework. Geneva, Switzerland: International Standard Organization; 1998.] allows us to make an LCA study quantifying the overall impact of a wind turbine and each of its components. Applying this methodology, the wind turbine is analysed during all the phases of its life cycle, from cradle to grave, with regard to the manufacture of its key components (through the incorporation of cut-off criteria), transport to the wind farm, subsequent installation, start-up, maintenance and final dismantling and stripping down into waste materials and their treatment. (author)

Technical and economical feasibility of the Rankine compression gas turbine (RCG)

NARCIS (Netherlands)

Ouwerkerk, H.; Lange, de H.C.

2006-01-01

The Rankine compression gas turbine (RCG) is a new type of combined cycle, i.e. combined steam and gas turbine installation, that returns all shaft power on one free power turbine. The novelty of the RCG is that the steam turbine drives the compressor of the gas turbine cycle. This way, the turbine

Thermal performance of a modified ammonia–water power cycle for reclaiming mid/low-grade waste heat

International Nuclear Information System (INIS)

Junye, Hua; Yaping, Chen; Jiafeng, Wu

2014-01-01

Highlights: • A modified Kalina cycle is proposed for power and heat cogeneration from mid/low-grade waste heat. • A water-cooling solution cooler is set for cogeneration of sanitary or heating hot water. • Work concentration is determined for suitable turbine inlet pressure and positive back pressure. • Basic concentration should match work concentration for higher efficiency. • Sanitary water with 50.7 °C and capacity of a quarter of total reclaimed heat load is cogenerated. - Abstract: A modified Kalina cycle was simulated, which is a triple-pressure ammonia–water power cycle adding a preheater and a water-cooling solution cooler to the original loop. The cycle acquires higher power recovery efficiency by realizing proper internal recuperation and suitable temperature-difference in phase change processes to match both heat source and cooling water. The influences of some key parameters on the thermodynamic performance of the cycle were discussed, including the work and basic concentrations of solution, circulation multiple and the turbine inlet temperature. It is shown that the basic concentration should match the work concentration for higher efficiency. Although higher work concentration could be slightly beneficial to cycle efficiency, the work concentration is mainly determined by considering the suitable turbine inlet/back pressure. Besides, this cycle can be used as a cogeneration system of power and sanitary or heating hot water. The calculation example presented finally with the turbine inlet parameters of 300 °C/6 MPa and the cycle lowest temperature of 30 °C shows that the power recovery efficiency reaches 15.87%, which is about 16.6% higher than that of the steam Rankine cycle. And it also provides 50.7 °C sanitary water with about a quarter of the total heating load reclaimed

Hourly weather forecasts for gas turbine power generation

Directory of Open Access Journals (Sweden)

G. Giunta

2017-06-01

Full Text Available An hourly short-term weather forecast can optimize processes in Combined Cycle Gas Turbine (CCGT plants by helping to reduce imbalance charges on the national power grid. Consequently, a reliable meteorological prediction for a given power plant is crucial for obtaining competitive prices for the electric market, better planning and stock management, sales and supplies of energy sources. The paper discusses the short-term hourly temperature forecasts, at lead time day+1 and day+2, over a period of thirteen months in 2012 and 2013 for six Italian CCGT power plants of 390 MW each (260 MW from the gas turbine and 130 MW from the steam turbine. These CCGT plants are placed in three different Italian climate areas: the Po Valley, the Adriatic coast, and the North Tyrrhenian coast. The meteorological model applied in this study is the eni-Kassandra Meteo Forecast (e‑kmf™, a multi-model approach system to provide probabilistic forecasts with a Kalman filter used to improve accuracy of local temperature predictions. Performance skill scores, computed by the output data of the meteorological model, are compared with local observations, and used to evaluate forecast reliability. In the study, the approach has shown good overall scores encompassing more than 50,000 hourly temperature values. Some differences from one site to another, due to local meteorological phenomena, can affect the short-term forecast performance, with consequent impacts on gas-to-power production and related negative imbalances. For operational application of the methodology in CCGT power plant, the benefits and limits have been successfully identified.

Optimization of power generation from shrouded wind turbines

Energy Technology Data Exchange (ETDEWEB)

Foote, Tudor; Agarwal, Ramesh [Department of Mechanical Engineering and Materials Science, Washington University in St. Louis (United States)

2013-07-01

In past several years, several studies have shown that the shrouded wind turbines can generate greater power compared to bare turbines. The objective of this study is to determine the potential of shrouded wind turbines for increased power generation by conducting numerical simulations. An analytical/computational study is performed by employing the well-known commercial Computational Fluid Dynamics (CFD) software FLUENT. An actuator disc model is used to model the turbine. The incompressible Navier-Stokes equations and a two equation realizable {kappa}-{epsilon} model are employed in the calculations. The power coefficient Cp and generated power are calculated for a large number of cases for horizontal axis wind turbines (HAWT) of various diameters and wind speeds for both bare and shrouded turbines. The design of the shroud is optimized by employing a single objective genetic algorithm; the objective being the maximization of the power coefficient Cp. It was found that the shroud indeed increases the Cp beyond the Betz’s limit significantly and as a result the generated power; this effect is consistent with that found in the recent literature that the shrouded wind-turbines can generate greater power than the bare turbines. The optimized shape of the shroud or diffuser further increases the generated power and Cp.

Comparative Evaluation of Integrated Waste Heat Utilization Systems for Coal-Fired Power Plants Based on In-Depth Boiler-Turbine Integration and Organic Rankine Cycle

Directory of Open Access Journals (Sweden)

Shengwei Huang

2018-01-01

Full Text Available To maximize the system-level heat integration, three retrofit concepts of waste heat recovery via organic Rankine cycle (ORC, in-depth boiler-turbine integration, and coupling of both are proposed, analyzed and comprehensively compared in terms of thermodynamic and economic performances. For thermodynamic analysis, exergy analysis is employed with grand composite curves illustrated to identify how the systems are fundamentally and quantitatively improved, and to highlight key processes for system improvement. For economic analysis, annual revenue and investment payback period are calculated based on the estimation of capital investment of each component to identify the economic feasibility and competitiveness of each retrofit concept proposed. The results show that the in-depth boiler-turbine integration achieves a better temperature match of heat flows involved for different fluids and multi-stage air preheating, thus a significant improvement of power output (23.99 MW, which is much larger than that of the system with only ORC (6.49 MW. This is mainly due to the limitation of the ultra-low temperature (from 135 to 75 °C heat available from the flue gas for ORC. The thermodynamic improvement is mostly contributed by the reduction of exergy destruction within the boiler subsystem, which is eventually converted to mechanical power; while the exergy destruction within the turbine system is almost not changed for the three concepts. The selection of ORC working fluids is performed to maximize the power output. Due to the low-grade heat source, the cycle with R11 offers the largest additional net power generation but is not significantly better than the other preselected working fluids. Economically, the in-depth boiler-turbine integration is the most economic completive solution with a payback period of only 0.78 year. The ORC concept is less attractive for a sole application due to a long payback time (2.26 years. However, by coupling both

BIOMASS GASIFICATION AND POWER GENERATION USING ADVANCED GAS TURBINE SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

David Liscinsky

2002-10-20

A multidisciplined team led by the United Technologies Research Center (UTRC) and consisting of Pratt & Whitney Power Systems (PWPS), the University of North Dakota Energy & Environmental Research Center (EERC), KraftWork Systems, Inc. (kWS), and the Connecticut Resource Recovery Authority (CRRA) has evaluated a variety of gasified biomass fuels, integrated into advanced gas turbine-based power systems. The team has concluded that a biomass integrated gasification combined-cycle (BIGCC) plant with an overall integrated system efficiency of 45% (HHV) at emission levels of less than half of New Source Performance Standards (NSPS) is technically and economically feasible. The higher process efficiency in itself reduces consumption of premium fuels currently used for power generation including those from foreign sources. In addition, the advanced gasification process can be used to generate fuels and chemicals, such as low-cost hydrogen and syngas for chemical synthesis, as well as baseload power. The conceptual design of the plant consists of an air-blown circulating fluidized-bed Advanced Transport Gasifier and a PWPS FT8 TwinPac{trademark} aeroderivative gas turbine operated in combined cycle to produce {approx}80 MWe. This system uses advanced technology commercial products in combination with components in advanced development or demonstration stages, thereby maximizing the opportunity for early implementation. The biofueled power system was found to have a levelized cost of electricity competitive with other new power system alternatives including larger scale natural gas combined cycles. The key elements are: (1) An Advanced Transport Gasifier (ATG) circulating fluid-bed gasifier having wide fuel flexibility and high gasification efficiency; (2) An FT8 TwinPac{trademark}-based combined cycle of approximately 80 MWe; (3) Sustainable biomass primary fuel source at low cost and potentially widespread availability-refuse-derived fuel (RDF); (4) An overall integrated

An optimal tuning strategy for tidal turbines

Science.gov (United States)

2016-01-01

Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This ‘impatient-tuning strategy’ results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing ‘patient-tuning strategy’ which maximizes the power output averaged over the tidal cycle. This paper presents a ‘smart patient tuning strategy’, which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine’s average power output. PMID:27956870

Bottoming organic Rankine cycle for a small scale gas turbine: A comparison of different solutions

International Nuclear Information System (INIS)

Clemente, Stefano; Micheli, Diego; Reini, Mauro; Taccani, Rodolfo

2013-01-01

Highlights: ► The ORC bottoming section for a commercial micro gas turbine has been studied. ► Six different organic working fluids have been considered and compared. ► The preliminary designs of both axial and radial turbines have been developed. ► Also scroll and reciprocating expanders have been analyzed for comparison. ► The best suited machine has to be selected after a detailed analysis in each case. - Abstract: Recently, several efforts have been devoted to the improvement of the thermal efficiency of small gas turbines, in order to approach the typical values of the internal combustion engines in the same range of power. One possibility is represented by a combined cycle, obtained coupling the gas turbine to a bottoming organic Rankine cycle (ORC). This paper deals with the definition of the main features of an ORC system aimed to recover heat from a 100 kWe commercial gas turbine with internal recuperator. After the optimization of the thermodynamic cycles, involving a comparison between six working fluids, different expanders are analyzed, with the aim of detecting, if possible, the best suited machine. First, single stage turbines, in both radial and axial flow configuration, are designed specifically for each considered fluid, in particular investigating the opportunity of mounting the ORC expander directly on the high-speed shaft of the gas turbine. Then, the performances of these dynamic machines are compared with those of positive displacement expanders, such as scroll devices, obtainable from commercial HVAC compressor with minor revisions, and reciprocating ones, here newly designed

A comparative analysis of rankine and absorption power cycles from exergoeconomic viewpoint

International Nuclear Information System (INIS)

Shokati, Naser; Ranjbar, Faramarz; Yari, Mortaza

2014-01-01

Highlights: • The Rankine and absorption power cycles are compared from exergoeconomic viewpoint. • The LiBr–H 2 O cycle has the highest unit cost of electricity produced by turbine. • The LiBr–H 2 O cycle has the lowest exergy destruction cost rate. • In LiBr–H 2 O cycle, the generator has the maximum value regarding (C-dot) D,k +(C-dot) L,k +(Z-dot) k . - Abstract: In this paper LiBr–H 2 O and NH 3 –H 2 O absorption power cycles and Rankine cycle which produce 1 MW electrical power in same conditions of heat sources are compared from exergoeconomic point of view. Exergoeconomic analysis is performed using the specific exergy costing (SPECO) method. The results show that among these cycles, although the LiBr–H 2 O cycle has the highest first law efficiency, but unit cost of electricity produced by turbine for LiBr–H 2 O cycle is more than that for Rankine cycle. This value is lowest for the NH 3 –H 2 O cycle. Moreover, the NH 3 –H 2 O cycle has the highest and the LiBr–H 2 O cycle has the lowest exergy destruction cost rate. The generator, the absorber and the boiler in all considered cycles have the maximum value of sum of cost rate associated with capital investment, operating and maintenance, exergy destruction and exergy losses. Therefore, these components should be taken into consideration from exergoeconomic viewpoint. In parametric study, it is observed that in the constant generator temperature, as the generator pressure increases, unit cost of power produced by turbine for LiBr–H 2 O and Rankine cycles decreases. This value for Rankine cycle is lower than for LiBr–H 2 O cycle whereas Rankine cycle efficiency is less than the efficiency of LiBr–H 2 O cycle. Also, in LiBr–H 2 O cycle, at constant temperature of the generator, the value of exergy destruction cost rate is minimized and exergoeconomic factor is maximized at particular values of generator pressure and the more absorber pressure results the minimum value of

1000 MW steam turbine for nuclear power station

International Nuclear Information System (INIS)

Drahy, J.

1987-01-01

Skoda Works started the manufacture of the 1000 MW steam turbine for the Temelin nuclear power plant. The turbine will use saturated steam at 3,000 r.p.m. It will allow steam supply to heat water for district heating, this of an output of 893 MW for a three-stage water heating at a temperature of 150/60 degC or of 570 MW for a two-stage heating at a temperature of 120/60 degC. The turbine features one high-pressure and three identical low-pressure stages. The pressure gradient between the high-pressure and the low-pressure parts was optimized as concerns the thermal efficiency of the cycle and the thermodynamic efficiency of the low-pressure part. A value of 0.79 MPa was selected corresponding to the maximum flow rate of the steam entering the turbine. This is 5,495 t/h, the admission steam parameters are 273.3 degC and 5.8 MPa. The feed water temperature is 220.9 degC. It is expected that throughout the life of the turbine, there will be 300 cold starts, 1,000 starts following shutdown for 55 to 88 hours, and 600 starts following shutdown for 8 hours. (Z.M.). 8 figs., 1 ref

Ways to increase efficiency of the HTGR coupled with the gas-turbine power conversion unit - HTR2008-58274

International Nuclear Information System (INIS)

Golovko, V. F.; Kodochigov, N. G.; Vasyaev, A. V.; Shenoy, A.; Baxi, C. B.

2008-01-01

The paper deals with the issue of increasing efficiency of nuclear power plants with the modular high-temperature helium reactor (HTGR) and direct gas turbine cycle. It should be noted that only this combination can highlight the advantages of the HTGR, namely the ability to heat helium to about 1000 deg. C, in comparison with other reactor plants for electricity generation. The HTGR has never been used in the direct gas turbine cycle. At present, several designs of such commercial plants are at the stage of experimental validation of main technical features. In Russia, 'OKB Mechanical Engineering' together with 'General Atomics' (USA) are developing the GT-MHR project with the reactor power of 600 MW, reactor outlet helium temperature of 850 deg. C, and efficiency of about 45.2%; the South African Republic is developing the PBMR project with the reactor power of 400 MW, reactor outlet helium temperature of 900 deg. C, and efficiency of about 42%; and Japan is developing the GTHTR-300 project with the reactor power of 600 MW, reactor outlet helium temperature of 850 deg. C, and efficiency of about 45.6%. As it has been proven by technical and economic estimations, one of the most important factors for successful promotion of reactor designs is their net efficiency, which must be not lower than 47%. A significant advantage of a reactor plant with the HTGR and gas-turbine power conversion unit over the steam cycle is considerable simplification of the power unit layout and reduction of the required equipment and systems (no steam generators, no turbine hall including steam lines, condenser, deaerator, etc.), which makes the gas-turbine power conversion unit more compact and less costly in production, operation and maintenance. However, in spite of this advantage, it seems that in the projects currently being developed, the potential of the gas-turbine cycle and high-temperature reactor to more efficiently generate electricity is not fully used. For example, in modern

Low speed turbines for nuclear power plants

International Nuclear Information System (INIS)

Ugol'nikov, V.V.; Kosyak, Yu.F.; Virchenko, M.A.

1975-01-01

Work of the Kharkov turbine plant on planning and manufacture for nuclear power plants of low-speed (1500 rpm) turbines with a power of 500-1000 MW is described. The selection of a construction diagram for the turbine assembly, determined basically by the presence or absence of parts of average pressure, is considered. Special construction features of the condenser and turbine are described. Turbine K-500, with a rate of 1500 rpm, was calculated for operation in a two-loop nuclear power plant with saturated steam with intermediate separation and two-stage steam regeneration. On the base of this turbine, three models of 1000-MW turbines were developed. The first model has a cylinder of average pressure (TsSD) and a lateral condenser. The second has no TsSD but a low location of the condensers. The third has no TsSD and the condensers are located laterally. Calculations of the heat efficiency of the three types of turbines showed that several advantages are offered by the model with a TsSD. Better aerodynamic properties of the exhaust nozzles and condensers with lateral location allows decreasing the specific heat consumption to 0.5-1% or, at the same power, a 10-20% decrease in cooling water consumption

Turbines for nuclear power plants. 2.ed.

International Nuclear Information System (INIS)

Troyanovskij, B.M.

1978-01-01

In the second edition of the book considered are practically all the main problems of calculation and operation of turbines and turbine installations of nuclear power plants. As compared to the first edition, essentially addes is the reproduction of the problem on combined generation of heat and electric energy. Also represented is detailed material on methods of preliminary evaluation of turbine effectiveness. Considered are peculiarities of turbine operation on wet steam and the basis of their thermal calculation. Much attention is payed to the problem of wet stream current in the turbine elements and wetness effect on their characteristics. Problems of wetness separation and moving blade erosion as well as other turbine elements are extracted in a special section. Given are structural schemes of different methods of innerchannel and periphery wet removal as well as experimental materials on their effectiveness. Given are descriptions and critical analysis of a great number of typical constructions of nuclear power plant steam turbines, produced by native plants as well as by the main foreign firms. Considered also are constructions of outside separators and steam superheaters. Separately given is the problem of rotation frequency choise of nuclear power plant wet steam turbines. Represented are materials on turbine installation tests, considered are the problems of turbine starting and manoeuvrability, analyzed are their typical jailures and damages. One of the sections of the book is devoted to gas turbine installations of nuclear power plants. Different material on this theme scattered before in various sources is summarized in the book

Supercritical Water Reactor Cycle for Medium Power Applications

International Nuclear Information System (INIS)

BD Middleton; J Buongiorno

2007-01-01

Scoping studies for a power conversion system based on a direct-cycle supercritical water reactor have been conducted. The electric power range of interest is 5-30 MWe with a design point of 20 MWe. The overall design objective is to develop a system that has minimized physical size and performs satisfactorily over a broad range of operating conditions. The design constraints are as follows: Net cycle thermal efficiency (ge)20%; Steam turbine outlet quality (ge)90%; and Pumping power (le)2500 kW (at nominal conditions). Three basic cycle configurations were analyzed. Listed in order of increased plant complexity, they are: (1) Simple supercritical Rankine cycle; (2) All-supercritical Brayton cycle; and (3) Supercritical Rankine cycle with feedwater preheating. The sensitivity of these three configurations to various parameters, such as reactor exit temperature, reactor pressure, condenser pressure, etc., was assessed. The Thermoflex software package was used for this task. The results are as follows: (a) The simple supercritical Rankine cycle offers the greatest hardware simplification, but its high reactor temperature rise and reactor outlet temperature may pose serious problems from the viewpoint of thermal stresses, stability and materials in the core. (b) The all-supercritical Brayton cycle is not a contender, due to its poor thermal efficiency. (c) The supercritical Rankine cycle with feedwater preheating affords acceptable thermal efficiency with lower reactor temperature rise and outlet temperature. (d) The use of a moisture separator improves the performance of the supercritical Rankine cycle with feedwater preheating and allows for a further reduction of the reactor outlet temperature, thus it was selected for the next step. Preliminary engineering design of the supercritical Rankine cycle with feedwater preheating and moisture separation was performed. All major components including the turbine, feedwater heater, feedwater pump, condenser, condenser pump

Design of large steam turbines for PWR power stations

International Nuclear Information System (INIS)

Hobson, G.; Muscroft, J.

1983-01-01

The thermodynamic cycle requirements for use with pressurized water reactors are reviewed and the manner in which thermal efficiency is maximised is outlined. The special nature of the wet steam cycle associated with turbines for this type of reactor is discussed. Machine and cycle parameters are optimised to achieve high thermal efficiency, particular attention being given to arrangements for water separation and steam reheating and to provisions for feedwater heating. Principles and details of mechanical design are considered for a range of both full-speed turbines running at 3000 rpm on 50 Hz systems and half-speed turbines running at 1800 rpm on 60 Hz systems. The importance of service experience with nuclear wet steam turbines and its relevance to the design of modern turbines for pressurized water reactor applications is discussed. (author)

Design of large steam turbines for PWR power stations

International Nuclear Information System (INIS)

Hobson, G.

1984-01-01

The authors review the thermodynamic cycle requirements for use with pressurized-water reactors, outline the way thermal efficiency is maximized, and discuss the special nature of the wet-steam cycle associated with turbines for this type of reactor. Machine and cycle parameters are optimized to achieve high thermal efficiency, particular attention being given to arrangements for water separation and steam reheating and to provisions for feedwater heating. Principles and details of mechanical design are considered for a range both of full-speed turbines running at 3000 rev/min on 50 Hz systems and of half-speed turbines running at 1800 rev/min on 60 Hz systems. The importance of service experience with nuclear wet-stream turbines, and its relevance to the design of modern turbines for PWR applications, is discussed. (author)

Maximisation of Combined Cycle Power Plant Efficiency

Directory of Open Access Journals (Sweden)

Janusz Kotowicz

2015-12-01

Full Text Available The paper presents concepts for increasing the efficiency of a modern combined cycle power plant. Improvement of gas turbine performance indicators as well as recovering heat from the air cooling the gas turbine’s flow system enable reaching gross electrical efficiencies of around 65%. Analyses for a wide range of compressor pressure ratios were performed. Operating characteristics were developed for the analysed combined cycle plant, for different types of open air cooling arrangements of the gas turbine’s expander: convective, transpiration and film.

Combined cycle solar central receiver hybrid power system study. Volume III. Appendices. Final technical report

Energy Technology Data Exchange (ETDEWEB)

None

1979-11-01

A design study for a 100 MW gas turbine/steam turbine combined cycle solar/fossil-fuel hybrid power plant is presented. This volume contains the appendices: (a) preconceptual design data; (b) market potential analysis methodology; (c) parametric analysis methodology; (d) EPGS systems description; (e) commercial-scale solar hybrid power system assessment; and (f) conceptual design data lists. (WHK)

Steam turbines for nuclear power plants

International Nuclear Information System (INIS)

Kosyak, Yu.F.

1978-01-01

Considered are the peculiarities of the design and operation of steam turbines, condensers and supplementary equipment of steam turbines for nuclear power plants; described are the processes of steam flow in humid-steam turbines, calculation and selection principles of main parameters of heat lines. Designs of the turbines installed at the Charkov turbine plant are described in detail as well as of those developed by leading foreign turbobuilding firms

Three dimensional optimization of small-scale axial turbine for low temperature heat source driven organic Rankine cycle

International Nuclear Information System (INIS)

Al Jubori, Ayad; Al-Dadah, Raya K.; Mahmoud, Saad; Bahr Ennil, A.S.; Rahbar, Kiyarash

2017-01-01

using working fluid R123 for a turbine with mean diameter of 70 mm, the maximum isentropic efficiency was about 88% and power output of 6.3 kW leading to cycle thermal efficiency of 10.5% showing an enhancement of 14.08% compared to the baseline design. Such results highlight the potential of the 3D optimization technique to improve the organic Rankine cycle performance.

Increasing power generation in horizontal axis wind turbines using optimized flow control

Science.gov (United States)

Cooney, John A., Jr.

complete design cycle was performed for the turbine model incorporated in the wind energy lab. Enhanced power generation was obtained through passive trailing edge shaping aimed at reaching lift and lift-to-drag goals predicted to optimize performance. These targets were determined by BEM analysis to improve power generation characteristics and annual energy production (AEP) for the wind turbine. A preliminary design was validated in wind tunnel experiments on a 2D rotor section in preparation for testing in the full atmospheric environment of the eWiND Laboratory. These tests were performed for the full-scale geometry and atmospheric conditions. Upon making additional improvements to the shape optimization tools, a series of trailing edge additions were designed to optimize power generation. The trailing edge additions were predicted to increase the AEP by up to 4.2% at the White Field site. The pieces were rapid-prototyped and installed on the wind turbine in March, 2014. Field tests are ongoing.

Development of Thermal Performance Analysis Computer Program on Turbine Cycle of Yoggwang 3,4 Units

Energy Technology Data Exchange (ETDEWEB)

Hong, S.Y.; Choi, K.H.; Jee, M.H.; Chung, S.I. [Korea Electric Power Research Institute, Taejon (Korea)

2002-07-01

The objective of the study ''Development of Thermal Performance Analysis Computer Program on Turbine Cycle of Yonggwang 3,4 Units'' is to utilize computerized program to the performance test of the turbine cycle or the analysis of the operational status of the thermal plants. In addition, the result can be applicable to the analysis of the thermal output at the abnormal status and be a powerful tool to find out the main problems for such cases. As a results, the output of this study can supply the way to confirm the technical capability to operate the plants efficiently and to obtain the economic gains remarkably. (author). 27 refs., 73 figs., 6 tabs.

Integrated analysis of wind turbines - The impact of power systems on wind turbine design

DEFF Research Database (Denmark)

Barahona Garzón, Braulio

Megawatt-size wind turbines nowadays operate in very complex environmental conditions, and increasingly demanding power system requirements. Pursuing a cost-effective and reliable wind turbine design is a multidisciplinary task. However nowadays, wind turbine design and research areas...... conditions that stem from disturbances in the power system. An integrated simulation environment, wind turbine models, and power system models are developed in order to take an integral perspective that considers the most important aeroelastic, structural, electrical, and control dynamics. Applications...... of the integrated simulation environment are presented. The analysis of an asynchronous machine, and numerical simulations of a fixedspeed wind turbine in the integrated simulation environment, demonstrate the effects on structural loads of including the generator rotor fluxes dynamics in aeroelastic studies. Power...

Actual characteristics study on HTR-10GT coupling with direct gas turbine cycle

International Nuclear Information System (INIS)

Peng Xuechuang; Zhu Shutang; Wang Jie

2005-01-01

HTR-10GT is a testing project coupling the reactor HTR-10 with direct gas turbine cycle. Its thermal cycle can be taken as a closed, recuperated and inter-cooled Brayton cycle. The present study is focused on the thermal cycle performance of HTR-10GT under practical conditions of leakage, pressure losses, etc.. Through thermodynamic analysis, the expression of cycle efficiency for actual thermal cycle is derived. By establishing a physical model with friction loss and leakage, a set of governing equation are constructed based on some reasonable assumptions. The results of actual cycle efficiency have been calculated for different leakage amount at different locations while the effects of leakage under different power level have also been calculated and analyzed. (authors)

Power Plants, Steam and Gas Turbines WebQuest

Directory of Open Access Journals (Sweden)

Carlos Ulloa

2012-10-01

Full Text Available A WebQuest is an Internet-based and inquiry-oriented learning activity. The aim of this work is to outline the creation of a WebQuest entitled “Power Generation Plants: Steam and Gas Turbines.” This is one of the topics covered in the course “Thermodynamics and Heat Transfer,” which is offered in the second year of Mechanical Engineering at the Defense University Center at the Naval Academy in Vigo, Spain. While participating in the activity, students will be divided into groups of no more than 10 for seminars. The groups will create PowerPoint presentations that include all of the analyzed aspects. The topics to be discussed during the workshop on power plant turbines are the: (1 principles of operation; (2 processes involved; (3 advantages and disadvantages; (4 efficiency; (5 combined cycle; and (6 transversal competences, such as teamwork, oral and written presentations, and analysis and synthesis of information. This paper presents the use of Google Sites as a guide to the WebQuest so that students can access all information online, including instructions, summaries, resources, and information on qualifications.

Thermodynamic simulation of a multi-step externally fired gas turbine powered by biomass

International Nuclear Information System (INIS)

Durante, A.; Pena-Vergara, G.; Curto-Risso, P.L.; Medina, A.; Calvo Hernández, A.

2017-01-01

Highlights: • A realistic model for an EFGT fueled with solid biomass is presented. • Detailed submodels for the HTHE and the chemical reactions are incorporated. • An arbitrary number of compression and expansion stages is considered. • Model validation leads to good agreement with experimental results. • A layout with two-stage compression leads to good efficiencies and power output. - Abstract: A thermodynamic model for a realistic Brayton cycle, working as an externally fired gas turbine fueled with biomass is presented. The use of an external combustion chamber, allows to burn dirty fuels to preheat pure air, which is the working fluid for the turbine. It also avoids direct contact of ashes with the turbine blades, resulting in a higher life cycle for the turbine. The model incorporates a high temperature heat exchanger and an arbitrary number of turbines and compressors, with the corresponding number of intercoolers and reheaters. It considers irreversibilities such as non-isentropic compressions and expansions, and pressure losses in heat input and release. The composition and temperature of the combustion gases, as well as the variable flow rate of air and combustion gases, are calculated for specific biomasses. The numerical model for a single stage configuration has been validated by comparing its predictions with the data sheets of two commercial turbines. Results are in good agreement. Curves on the dependence of thermal efficiency and power output with the overall pressure ratio will be shown for several plant configurations with variable number of compression/expansion stages. Also the influence of different types of biomasses and their moisture will be analyzed on parameters such as fuel consumption and exhaust gases temperature. For a single step plant layout fueled with eucalyptus wood an efficiency of 23% is predicted, whereas for a configuration with two compressors and one turbine efficiency increases up to 25%. But it is remarkable

The Benefit of Variable-Speed Turbine Operation for Low Temperature Thermal Energy Power Recovery

OpenAIRE

Brasz, Joost J.

2014-01-01

This paper analyzes, given the large variation in turbine discharge pressure with changing ambient temperatures, whether variable-speed radial-inflow turbine operation has a similar benefit for Organic Rankine Cycle (ORC) power recovery systems as variable-speed centrifugal compression has for chiller applications. The benefit of variable-speed centrifugal compression over fixed-speed operation is a reduction in annual electricity consumption of almost 40 %. Air-conditioning systems are by ne...

Thermo-economic performance of HTGR Brayton power cycles

International Nuclear Information System (INIS)

Linares, J. L.; Herranz, L. E.; Moratilla, B. Y.; Fernandez-Perez, A.

2008-01-01

High temperature reached in High and Very High Temperature Reactors (VHTRs) results in thermal efficiencies substantially higher than those of actual nuclear power plants. A number of studies mainly driven by achieving optimum thermal performance have explored several layout. However, economic assessments of cycle power configurations for innovative systems, although necessarily uncertain at this time, may bring valuable information in relative terms concerning power cycle optimization. This paper investigates the thermal and economic performance direct Brayton cycles. Based on the available parameters and settings of different designs of HTGR power plants (GTHTR-300 and PBMR) and using the first and second laws of thermodynamics, the effects of compressor inter-cooling and of the compressor-turbine arrangement (i.e., single vs. multiple axes) on thermal efficiency have been estimated. The economic analysis has been based on the El-Sayed methodology and on the indirect derivation of the reactor capital investment. The results of the study suggest that a 1-axis inter-cooled power cycle has a similar thermal performance to the 3-axes one (around 50%) and, what's more, it is substantially less taxed. A sensitivity study allowed assessing the potential impact of optimizing several variables on cycle performance. Further than that, the cycle components costs have been estimated and compared. (authors)

Future on Power Electronics for Wind Turbine Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ma, Ke

2013-01-01

networks and more and more wind power stations, acting as power plants, are connected directly to the transmission networks. As the grid penetration and power level of the wind turbines increase steadily, the wind power starts to have significant impacts to the power grid system. Therefore, more advanced...... generators, power electronic systems, and control solutions have to be introduced to improve the characteristics of the wind power plant and make it more suitable to be integrated into the power grid. Meanwhile, there are also some emerging technology challenges, which need to be further clarified......Wind power is still the most promising renewable energy in the year of 2013. The wind turbine system (WTS) started with a few tens of kilowatt power in the 1980s. Now, multimegawatt wind turbines are widely installed even up to 6-8 MW. There is a widespread use of wind turbines in the distribution...

Water turbine technology for small power stations

Science.gov (United States)

Salovaara, T.

1980-02-01

The paper examines hydro-power stations and the efficiency and costs of using water turbines to run them. Attention is given to different turbine types emphasizing the use of Kaplan-turbines and runners. Hydraulic characteristics and mechanical properties of low head turbines and small turbines, constructed of fully fabricated steel plate structures, are presented.

Global Value Chain and Manufacturing Analysis on Geothermal Power Plant Turbines

Energy Technology Data Exchange (ETDEWEB)

Akar, Sertac [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Augustine, Chad R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurup, Parthiv [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mann, Margaret K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-04

The global geothermal electricity market has significantly grown over the last decade and is expected to reach a total installed capacity of 18.4 GWe in 2021 (GEA, 2016). Currently, geothermal project developers customize the size of the power plant to fit the resource being developed. In particular, the turbine is designed and sized to optimize efficiency and resource utilization for electricity production; most often, other power plant components are then chosen to complement the turbine design. These custom turbine designs demand one-off manufacturing processes, which result in higher manufacturing setup costs, longer lead-times, and higher capital costs overall in comparison to larger-volume line manufacturing processes. In contrast, turbines produced in standard increments, manufactured in larger volumes, could result in lower costs per turbine. This study focuses on analysis of the global supply chain and manufacturing costs for Organic Rankine Cycle (ORC) turboexpanders and steam turbines used in geothermal power plants. In this study, we developed a manufacturing cost model to identify requirements for equipment, facilities, raw materials, and labor. We analyzed three different cases 1) 1 MWe geothermal ORC turboexpander 2) 5 MWe ORC turboexpander and 3) 20 MWe geothermal steam turbine, and calculated the cost of manufacturing the major components, such as the impellers/blades, shaft/rotor, nozzles, inlet guide lanes, disks, and casings. Then we used discounted cash flow (DCF) analysis to calculate the minimum sustainable price (MSP). MSP is the minimum price that a company must sell its product for in order to pay back the capital and operating expenses during the plant lifetime (CEMAC, 2017). The results showed that MSP could highly vary between 893 dollar/kW and 30 dollar/kW based on turbine size, standardization and volume of manufacturing. The analysis also showed that the economy of scale applies both to the size of the turbine and the number

Effects of syngas type on the operation and performance of a gas turbine in integrated gasification combined cycle

International Nuclear Information System (INIS)

Kim, Young Sik; Lee, Jong Jun; Kim, Tong Seop; Sohn, Jeong L.

2011-01-01

Research highlights: → The effect of firing syngas in a gas turbine designed for natural gas was investigated. → A full off-design analysis was performed for a wide syngas heating value range. → Restrictions on compressor surge margin and turbine metal temperature were considered. -- Abstract: We investigated the effects of firing syngas in a gas turbine designed for natural gas. Four different syngases were evaluated as fuels for a gas turbine in the integrated gasification combined cycle (IGCC). A full off-design analysis of the gas turbine was performed. Without any restrictions on gas turbine operation, as the heating value of the syngas decreases, a greater net system power output and efficiency is possible due to the increased turbine mass flow. However, the gas turbine is more vulnerable to compressor surge and the blade metal becomes more overheated. These two problems can be mitigated by reductions in two parameters: the firing temperature and the nitrogen flow to the combustor. With the restrictions on surge margin and metal temperature, the net system performance decreases compared to the cases without restrictions, especially in the surge margin control range. The net power outputs of all syngas cases converge to a similar level as the degree of integration approaches zero. The difference in net power output between unrestricted and restricted operation increases as the fuel heating value decreases. The optimal integration degree, which shows the greatest net system power output and efficiency, increases with decreasing syngas heating value.

Effects of syngas type on the operation and performance of a gas turbine in integrated gasification combined cycle

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Sik; Lee, Jong Jun [Graduate School, Inha University, Incheon 402-751 (Korea, Republic of); Kim, Tong Seop, E-mail: kts@inha.ac.k [Dept. of Mechanical Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Sohn, Jeong L. [Center for Next Generation Heat Exchangers, Busan 618-230 (Korea, Republic of)

2011-05-15

Research highlights: {yields} The effect of firing syngas in a gas turbine designed for natural gas was investigated. {yields} A full off-design analysis was performed for a wide syngas heating value range. {yields} Restrictions on compressor surge margin and turbine metal temperature were considered. -- Abstract: We investigated the effects of firing syngas in a gas turbine designed for natural gas. Four different syngases were evaluated as fuels for a gas turbine in the integrated gasification combined cycle (IGCC). A full off-design analysis of the gas turbine was performed. Without any restrictions on gas turbine operation, as the heating value of the syngas decreases, a greater net system power output and efficiency is possible due to the increased turbine mass flow. However, the gas turbine is more vulnerable to compressor surge and the blade metal becomes more overheated. These two problems can be mitigated by reductions in two parameters: the firing temperature and the nitrogen flow to the combustor. With the restrictions on surge margin and metal temperature, the net system performance decreases compared to the cases without restrictions, especially in the surge margin control range. The net power outputs of all syngas cases converge to a similar level as the degree of integration approaches zero. The difference in net power output between unrestricted and restricted operation increases as the fuel heating value decreases. The optimal integration degree, which shows the greatest net system power output and efficiency, increases with decreasing syngas heating value.

THERMODYNAMIC ANALYSIS AND SIMULATION OF A NEW COMBINED POWER AND REFRIGERATION CYCLE USING ARTIFICIAL NEURAL NETWORK

Directory of Open Access Journals (Sweden)

Hossein Rezvantalab

2011-01-01

Full Text Available In this study, a new combined power and refrigeration cycle is proposed, which combines the Rankine and absorption refrigeration cycles. Using a binary ammonia-water mixture as the working fluid, this combined cycle produces both power and refrigeration output simultaneously by employing only one external heat source. In order to achieve the highest possible exergy efficiency, a secondary turbine is inserted to expand the hot weak solution leaving the boiler. Moreover, an artificial neural network (ANN is used to simulate the thermodynamic properties and the relationship between the input thermodynamic variables on the cycle performance. It is shown that turbine inlet pressure, as well as heat source and refrigeration temperatures have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. In addition, the results of ANN are in excellent agreement with the mathematical simulation and cover a wider range for evaluation of cycle performance.

Optimized Application of MSR and Steam Turbine Retrofits in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Crossland, Robert; McCoach, John [ALSTOM Power, Willans Works, Newbold Road, Rugby, Warwickshire CV21 2NH (United Kingdom); Gagelin, Jean-Philippe [ALSTOM Power Heat Exchange, 19-21 avenue Morane-Saulnier, BP 65, 78143 Velizy Cedex (France)

2004-07-01

The benefit to a nuclear power plant from a steam turbine retrofit has often been clearly demonstrated in recent years but, for light water nuclear plants, the Moisture Separator Reheaters (MSRs) are also of prime importance. This paper describes how refurbishment of these crucial components can only provide full potential performance benefit when made in conjunction with a steam turbine retrofit (although in practice these activities are frequently separated). Examples are given to show how combined application is best handled within a single organization to ensure optimized integration into the thermal cycle. (authors)

Optimized Application of MSR and Steam Turbine Retrofits in Nuclear Power Plants

International Nuclear Information System (INIS)

Crossland, Robert; McCoach, John; Gagelin, Jean-Philippe

2004-01-01

The benefit to a nuclear power plant from a steam turbine retrofit has often been clearly demonstrated in recent years but, for light water nuclear plants, the Moisture Separator Reheaters (MSRs) are also of prime importance. This paper describes how refurbishment of these crucial components can only provide full potential performance benefit when made in conjunction with a steam turbine retrofit (although in practice these activities are frequently separated). Examples are given to show how combined application is best handled within a single organization to ensure optimized integration into the thermal cycle. (authors)

Exergy analysis of gas turbine with air bottoming cycle

International Nuclear Information System (INIS)

Ghazikhani, M.; Khazaee, I.; Abdekhodaie, E.

2014-01-01

In this paper, the exergy analysis of a conventional gas turbine and a gas turbine with air bottoming cycle (ABC) is presented in order to study the important parameters involved in improving the performance characteristics of the ABC based on the Second Law of thermodynamics. In this study, work output, specific fuel consumption (SFC) and the exergy destruction of the components are investigated using a computer model. The variations of the ABC cycle exergy parameters are comprehensively discussed and compared with those of the simple gas turbine. The results indicate that the amount of the exhaust exergy recovery in different operating conditions varies between 8.6 and 14.1% of the fuel exergy, while the exergy destruction due to the extra components in the ABC makes up only 4.7–7.4% of the fuel exergy. This is the reason why the SFC of the ABC is averagely 13.3% less and the specific work 15.4% more than those of the simple gas turbine. The results also reveal that in the ABC cycle, at a small value of pressure ratio, a higher specific work with lower SFC can be achieved in comparison with those of the simple gas turbine. - Highlights: • Exhaust exergy recovery in ABC gas turbine varies with 8.6–14.1% of the fuel exergy. • Irreversibility of the extra devices in ABC makes up 4.7–7.4% of the fuel exergy. • SFC in ABC is poor due to exergy recovery more than extra devices irreversibility. • At the same TIT and R c , specific work in the ABC is more than simple gas turbine. • The recuperator has the largest contribution in the irreversibility of the ABC

Quantitative indexes of gas-steam thermo electrical power plants thermodynamical cycles; Indices quantitativos de ciclos termodinamicos de centrais termoeletricas de gas-vapor

Energy Technology Data Exchange (ETDEWEB)

Vlassov, D.; Vargas, J.V.C. [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica]. E-mails: vlassov@demec.ufpr.br; jvargas@demec.ufpr.br

2002-07-01

This paper analyses various thermal schemes of the world wide most used cycles in gas-steam thermoelectric power plants. The combination of gas turbine cycle with the steam-gas cycle in thermoelectric power plants is performed in several ways, resulting in different thermal schemes, used equipment and operation plant basic characteristics. The thermal scheme of a gas-steam power plant is a determinant factor for the definition of energetic, economic and ecological characteristics. For the comparative analysis various quantitative indexes are presented, as for example: the heat fraction supplied to the gas turbine cycle and the cycle binary rate.

Wind Turbine Generator System Power Performance Test Report for the ARE442 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

van Dam, J.; Jager, D.

2010-02-01

This report summarizes the results of a power performance test that NREL conducted on the ARE 442 wind turbine. This test was conducted in accordance with the International Electrotechnical Commission's (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. However, because the ARE 442 is a small turbine as defined by IEC, NREL also followed Annex H that applies to small wind turbines. In these summary results, wind speed is normalized to sea-level air density.

Power Electronics as key technology in wind turbines

DEFF Research Database (Denmark)

Blaabjerg, Frede

2005-01-01

This paper discuss the development in wind turbines in a two-decade perspective looking at the technology based on track records. Different power electronic topologies for interfacing the wind turbine to the grid are discussed and related to the possibility for the wind turbine to act as a power...

High-power condensation turbine application to district heating

International Nuclear Information System (INIS)

Virchenko, M.A.; Arkad'ev, B.A.; Ioffe, V.Yu.

1982-01-01

In general outline the role of condensation turbines in NPP district heating is considered. The expediency of expansion of central heating loading of turbines of operating as well as newly designed condensation power plants on the basis of the WWER-1000-type reactors is shown. The principle heat flowsheet of the 1000 MW power turbine is given. An advantage in using turbines with uncontrolled steam bleeding is pointed out [ru

Improvements in steam cycle electric power generating plants

International Nuclear Information System (INIS)

Bienvenu, Claude.

1973-01-01

The invention relates to a steam cycle electric energy generating plants of the type comprising a fossil or nuclear fuel boiler for generating steam and a turbo alternator group, the turbine of which is fed by the boiler steam. The improvement is characterized in that use is made of a second energy generating group in which a fluid (e.g. ammoniac) undergoes a condensation cycle the heat source of said cycle being obtained through a direct or indirect heat exchange with a portion of the boiler generated steam whereby it is possible without overloading the turbo-alternator group, to accomodate any increase of the boiler power resulting from the use of another fuel while maintaining a maximum energy output. This can be applied to electric power stations [fr

The effective use of gas turbines and combined cycle technology in heat and electrical energy production

International Nuclear Information System (INIS)

Boehm, B.; Stark, E.

1999-01-01

The modernization of the energy industry in many countries is a real challenge for both, the policy makers as well as for the power industry. Especially, the efficient satisfaction of the heat and electrical demand of big cities will remain an interesting task for supply companies and hence for today engineers and economists, because the availability of natural gas from Russia and from other deposits owning countries for the decades to come, cogeneration by using modern gas turbines and combined cycle technologies is a key and corner stone of supply, not the least for its very low emission and small environmental loading. It is the intention of this paper, to demonstrate under resource to: 1) the high potential of natural gas-based cogeneration; 2) the high efficiency of gas turbines and combined cycle plants; 3) their flexibility to cover different demands; 4) the operational experience with gas turbines and combined cycle cogeneration plants; 5) the very good environmental behavior of gas turbines. Actually, the highest utilization of primary energy resources is afforded with natural gas and described technology. Future gradual rise of gas prices can bring about a shift from the present main application in high efficiency load plants to mid range load operation of cogeneration plants. (Author)

Thermodynamic analysis of turbine blade cooling on the performance of gas turbine cycle

International Nuclear Information System (INIS)

Sarabchi, K.; Shokri, M.

2002-01-01

Turbine inlet temperature strongly affects gas turbine performance. Today blade cooling technologies facilitate the use of higher inlet temperatures. Of course blade cooling causes some thermodynamic penalties that destroys to some extent the positive effect of higher inlet temperatures. This research aims to model and evaluate the performance of gas turbine cycle with air cooled turbine. In this study internal and transpiration cooling methods has been investigated and the penalties as the result of gas flow friction, cooling air throttling, mixing of cooling air flow with hot gas flow, and irreversible heat transfer have been considered. In addition, it is attempted to consider any factor influencing actual conditions of system in the analysis. It is concluded that penalties due to blade cooling decrease as permissible temperature of the blade surface increases. Also it is observed that transpiration method leads to better performance of gas turbine comparing to internal cooling method

Robust control of speed and temperature in a power plant gas turbine.

Science.gov (United States)

Najimi, Ebrahim; Ramezani, Mohammad Hossein

2012-03-01

In this paper, an H(∞) robust controller has been designed for an identified model of MONTAZER GHAEM power plant gas turbine (GE9001E). In design phase, a linear model (ARX model) which is obtained using real data has been applied. Since the turbine has been used in a combined cycle power plant, its speed and also the exhaust gas temperature should be adjusted simultaneously by controlling fuel signals and compressor inlet guide vane (IGV) position. Considering the limitations on the system inputs, the aim of the control is to maintain the turbine speed and the exhaust gas temperature within desired interval under uncertainties and load demand disturbances. Simulation results of applying the proposed robust controller on the nonlinear model of the system (NARX model), fairly fulfilled the predefined aims. Simulations also show the improvement in the performance compared to MPC and PID controllers for the same conditions. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Sensitivity analysis of system parameters on the performance of the Organic Rankine Cycle system for binary-cycle geothermal power plants

International Nuclear Information System (INIS)

Liu, Xiaomin; Wang, Xing; Zhang, Chuhua

2014-01-01

The main purpose of this paper is to analyze the sensitivity of system parameters to the performance of the Organic Rankine Cycle (ORC) system quantitatively. A thermodynamic model of the ORC system for binary-cycle geothermal power plants has been developed and verified. The system parameters, such as working fluid, superheat temperature, pinch temperature difference in evaporator and condenser, evaporating temperature, the isentropic efficiencies of the cycle pump and radial inflow turbine are selected as six factors for orthogonal design. The order of factors sensitivity on performance indices of the net power output of the ORC system, the thermal efficiency, the size parameter of radial inflow turbine, the power decrease factor of the pump and the total heat transfer capacity are determined by the range obtained from the orthogonal design. At different geothermal temperatures, the ranges of the six factors corresponding to performance indices are analyzed respectively. The results show that the geothermal temperature influences the range of the factors to the net power output, SP factor of radial inflow turbine, and the total heat transfer capacity, but it has no effect for the range of the factors for the thermal efficiency and the power decrease factor of the pump. The evaporating temperature is always the primary or secondary factor that influence the thermodynamic and economic performance of the ORC system. This study would provide useful references for determining the proper design variables in the performance optimization of the ORC system at different geothermal temperatures. - Highlights: • Evaporating temperature has significant effect on performance of ORC system. • Order of system parameters' sensitivity to the performance of ORC is revealed. • Effect of system parameters on performance indices vary with geothermal temperature. • Geothermal temperature has no effect on range of six factors to the size of turbine

Analysis of a BWR direct cycle forced circulation power plants operation

International Nuclear Information System (INIS)

Andrade, G.G. de.

1973-01-01

First, it is established a general view over the operational problems of the BWR direct cycle forced circulation power plants, and then it is analysed the possibility of the utilization of the energy purged from the turbine as an additional energy for the electrical generation. To simulate the BWR power plant and to obtain the solution of the mathematical model it was developed a computer code named ATOR which shows the feasibility of the proposed method. In this way it is shown the possibility to get a better maneuvering allowance for the BWR power plant whenever it is permitted a convenient use of the vapor extracted from the turbine for the feedwater pre-heaters of the reactor. (author)

Design and development of gas cooled reactors with closed cycle gas turbines. Proceedings of a technical committee meeting

International Nuclear Information System (INIS)

1996-08-01

Technological advances over the past fifteen years in the design of turbomachinery, recuperators and magnetic bearings provide the potential for a quantum improvement in nuclear power generation economics through the use of the HTGR with a closed cycle gas turbine. Enhanced international co-operation among national gas cooled reactor programmes in these common technology areas could facilitate the development of this nuclear power concept thereby achieving safety, environmental and economic benefits with overall reduced development costs. This TCM and Workshop was convened to provide the opportunity to review and examine the status of design activities and technology development in national HTGR programmes with specific emphasis on the closed cycle gas turbine, and to identify pathways which take advantage of the opportunity for international co-operation in the development of this concept. Refs, figs, tabs

Design and development of gas cooled reactors with closed cycle gas turbines. Proceedings of a technical committee meeting

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-08-01

Technological advances over the past fifteen years in the design of turbomachinery, recuperators and magnetic bearings provide the potential for a quantum improvement in nuclear power generation economics through the use of the HTGR with a closed cycle gas turbine. Enhanced international co-operation among national gas cooled reactor programmes in these common technology areas could facilitate the development of this nuclear power concept thereby achieving safety, environmental and economic benefits with overall reduced development costs. This TCM and Workshop was convened to provide the opportunity to review and examine the status of design activities and technology development in national HTGR programmes with specific emphasis on the closed cycle gas turbine, and to identify pathways which take advantage of the opportunity for international co-operation in the development of this concept. Refs, figs, tabs.

Optimal integration of linear Fresnel reflector with gas turbine cogeneration power plant

International Nuclear Information System (INIS)

Dabwan, Yousef N.; Mokheimer, Esmail M.A.

2017-01-01

generating capacities of the gas turbine and different areas of solar collectors have been examined. Thermoflow software simulation results have been used to identify the optimal configuration and sizing of the gas turbine and the solar field of the integrated solar gas turbine cogeneration plant (ISGCPP) required to achieve the required steam generation with the minimum cost and environmental impact. The study revealed that ISGCPP can reduce the levelized electricity cost by 76–85% relative to the fully-solar-powered LFR power plant. Moreover, the study identified the configuration of ISGCPP with a gas turbine size of 50 MWe capacity and 93 ha of LFR solar field as the optimally integrated plant. It reduces the annual CO 2 emission by 100 k Tonne (18%) in comparison with that emitted by the corresponding conventional plant with 50 MWe and 400 k tonne (43.75%) compared with that emitted by the original conventional plant with a gas turbine if 150 MWe power generation capacity. The study revealed also that integrating the LFR technology with a gas turbine cogeneration power plant in locations with high solar insolation was proved to have more economic feasibility than CO 2 capturing technology. Under Dhahran weather conditions, the LEC of about 5 USȻ/kW h is obtained using the proposed optimally configured ISGCPP compared with about 7.5 USȻ/kW h obtained by the corresponding conventional cycle integrated with carbon capture technology. In other words, the ISGCPP reduces the LEC by 50% while achieving the same reduction of CO 2 emission by an equivalent conventional plant integrated with carbon capture technology.

Steam turbine generators for Sizewell 'B' nuclear power station

International Nuclear Information System (INIS)

Hesketh, J.A.; Muscroft, J.

1990-01-01

The thermodynamic cycle of the modern 3000 r/min steam turbine as applied at Sizewell 'B' is presented. Review is made of the factors affecting thermal efficiency including the special nature of the wet steam cycle and the use of moisture separation and steam reheating. Consideration is given to the optimization of the machine and cycle parameters, including particular attention to reheating and to the provision of feedheating, in order to achieve a high overall level of performance. A modular design approach has made available a family of machines suitable for the output range 600-1300 MW. The constructional features of the 630 MW Sizewell 'B' turbine generators from this range are described in detail. The importance of service experience with wet steam turbines and its influence on the design of modern turbines for pressurized water reactor (PWR) applications is discussed. (author)

High Power Electronics - Key Technology for Wind Turbines

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ma, Ke

2014-01-01

reliability challenges for the future wind turbines are explained. It is concluded that the wind turbine behavior/performance can be significantly improved by introducing power electronics, and there will be higher requirements for the power electronics performances in wind power application....

Performance estimation of Tesla turbine applied in small scale Organic Rankine Cycle (ORC) system

International Nuclear Information System (INIS)

Song, Jian; Gu, Chun-wei; Li, Xue-song

2017-01-01

Highlights: • One-dimensional model of the Tesla turbine is improved and applied in ORC system. • Working fluid properties and system operating conditions impact efficiency. • The influence of turbine efficiency on ORC system performance is evaluated. • Potential of using Tesla turbine in ORC systems is estimated. - Abstract: Organic Rankine Cycle (ORC) system has been proven to be an effective method for the low grade energy utilization. In small scale applications, the Tesla turbine offers an attractive option for the organic expander if an efficient design can be achieved. The Tesla turbine is simple in structure and is easy to be manufactured. This paper improves the one-dimensional model for the Tesla turbine, which adopts a non-dimensional formulation that identifies the dimensionless parameters that dictates the performance features of the turbine. The model is used to predict the efficiency of a Tesla turbine that is applied in a small scale ORC system. The influence of the working fluid properties and the operating conditions on the turbine performance is evaluated. Thermodynamic analysis of the ORC system with different organic working fluids and under various operating conditions is conducted. The simulation results reveal that the ORC system can generate a considerable net power output. Therefore, the Tesla turbine can be regarded as a potential choice to be applied in small scale ORC systems.

Exergy analysis of a gas turbine power plant | Oko | Journal of ...

African Journals Online (AJOL)

Exergy analysis of a 100MW gas turbine power plant that works on the. Brayton cycle is presented. The average increase in the thermodynamic degradation of the plant over the period of six (6) years at three different levels of load was assessed. The exergy analysis of the plant was done on two sets of data: one from the ...

HTGR-GT closed-cycle gas turbine: a plant concept with inherent cogeneration (power plus heat production) capability

International Nuclear Information System (INIS)

McDonald, C.F.

1980-04-01

The high-grade sensible heat rejection characteristic of the high-temperature gas-cooled reactor-gas turbine (HTGR-GT) plant is ideally suited to cogeneration. Cogeneration in this nuclear closed-cycle plant could include (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. This paper discusses the HTGR-GT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes. This paper concludes that the HTGR-GT plant, which can potentially approach a 50% overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation

Parametric optimization design for supercritical CO2 power cycle using genetic algorithm and artificial neural network

International Nuclear Information System (INIS)

Wang Jiangfeng; Sun Zhixin; Dai Yiping; Ma Shaolin

2010-01-01

Supercritical CO 2 power cycle shows a high potential to recover low-grade waste heat due to its better temperature glide matching between heat source and working fluid in the heat recovery vapor generator (HRVG). Parametric analysis and exergy analysis are conducted to examine the effects of thermodynamic parameters on the cycle performance and exergy destruction in each component. The thermodynamic parameters of the supercritical CO 2 power cycle is optimized with exergy efficiency as an objective function by means of genetic algorithm (GA) under the given waste heat condition. An artificial neural network (ANN) with the multi-layer feed-forward network type and back-propagation training is used to achieve parametric optimization design rapidly. It is shown that the key thermodynamic parameters, such as turbine inlet pressure, turbine inlet temperature and environment temperature have significant effects on the performance of the supercritical CO 2 power cycle and exergy destruction in each component. It is also shown that the optimum thermodynamic parameters of supercritical CO 2 power cycle can be predicted with good accuracy using artificial neural network under variable waste heat conditions.

Parametric-based thermodynamic analysis of organic Rankine cycle as bottoming cycle for combined-cycle power plant

International Nuclear Information System (INIS)

Qureshi, S.; Memon, A.G.; Abbasi, A.F.

2017-01-01

In Pakistan, the thermal efficiency of the power plants is low because of a huge share of fuel energy is dumped into the atmosphere as waste heat. The ORC (Organic Rankine Cycle) has been revealed as one of the promising technologies to recover waste heat to enhance the thermal efficiency of the power plant. In current work, ORC is proposed as a second bottoming cycle for existing CCPP (Combined Cycle Power Plant). In order to assess the efficiency of the plant, a thermodynamic model is developed in the ESS (Engineering Equation Solver) software. The developed model is used for parametric analysis to assess the effects of various operating parameters on the system performance. The analysis of results shows that the integration of ORC system with existing CCPP system enhances the overall power output in the range of 150.5-154.58 MW with 0.24-5% enhancement in the efficiency depending on the operating conditions. During the parametric analysis of ORC, it is observed that inlet pressure of the turbine shows a significant effect on the performance of the system as compared to other operating parameters. (author)

Preheating of fluid in a supercritical Brayton cycle power generation system at cold startup

Science.gov (United States)

Wright, Steven A.; Fuller, Robert L.

2016-07-12

Various technologies pertaining to causing fluid in a supercritical Brayton cycle power generation system to flow in a desired direction at cold startup of the system are described herein. A sensor is positioned at an inlet of a turbine, wherein the sensor is configured to output sensed temperatures of fluid at the inlet of the turbine. If the sensed temperature surpasses a predefined threshold, at least one operating parameter of the power generation system is altered.

LCA-LCCA of oil fired steam turbine power plant in Singapore

International Nuclear Information System (INIS)

Kannan, R.; Tso, C.P.; Osman, Ramli; Ho, H.K.

2004-01-01

A life cycle assessment (LCA) was conducted to quantify the non-renewable energy use and global warming potential in electricity generation from a typical oil fired steam turbine plant in Singapore. As the conventional LCA does not include any cost analysis, which is a major criterion in decision making, the cost of power generation is estimated using a life cycle cost analysis (LCCA) tool. It is estimated that the hidden processes consumed about 9% additional energy on top of the fuel embedded energy, while the hidden GHG emission is about 12%. A correlation is established to estimate the life cycle energy use and GHG emissions directly from the power plant net efficiency. The study methodology, results and the empirical relations are presented, together with a brief overview of the Singapore power sector. It also highlights the need for consideration of the reserves availability in the pricing mechanism and how such cost indices could be developed based on the LCA-LCCA. (Author)

LCA-LCCA of oil fired steam turbine power plant in Singapore

International Nuclear Information System (INIS)

Kannan, R.; Tso, C.P.; Osman, Ramli; Ho, H.K.

2004-01-01

A life cycle assessment (LCA) was conducted to quantify the non-renewable energy use and global warming potential in electricity generation from a typical oil fired steam turbine plant in Singapore. As the conventional LCA does not include any cost analysis, which is a major criterion in decision making, the cost of power generation is estimated using a life cycle cost analysis (LCCA) tool. It is estimated that the hidden processes consumed about 9% additional energy on top of the fuel embedded energy, while the hidden GHG emission is about 12%. A correlation is established to estimate the life cycle energy use and GHG emissions directly from the power plant net efficiency. The study methodology, results and the empirical relations are presented, together with a brief overview of the Singapore power sector. It also highlights the need for consideration of the reserves availability in the pricing mechanism and how such cost indices could be developed based on the LCA-LCCA

Global Value Chain and Manufacturing Analysis on Geothermal Power Plant Turbines: Preprint

Energy Technology Data Exchange (ETDEWEB)

Akar, Sertac [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Augustine, Chad R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurup, Parthiv [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mann, Margaret K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-11-03

The global geothermal electricity market has significantly grown over the last decade and is expected to reach a total installed capacity of 18.4 GWe in 2021 (GEA, 2016). Currently, geothermal project developers customize the size of the power plant to fit the resource being developed. In particular, the turbine is designed and sized to optimize efficiency and resource utilization for electricity production; most often, other power plant components are then chosen to complement the turbine design. These custom turbine designs demand one-off manufacturing processes, which result in higher manufacturing setup costs, longer lead-times, and higher capital costs overall in comparison to larger-volume line manufacturing processes. In contrast, turbines produced in standard increments, manufactured in larger volumes, could result in lower costs per turbine. This study focuses on analysis of the global supply chain and manufacturing costs for Organic Rankine Cycle (ORC) turboexpanders and steam turbines used in geothermal power plants. In this study, we developed a manufacturing cost model to identify requirements for equipment, facilities, raw materials, and labor. We analyzed three different cases 1) 1 MWe geothermal ORC turboexpander 2) 5 MWe ORC turboexpander and 3) 20 MWe geothermal steam turbine, and calculated the cost of manufacturing the major components, such as the impellers/blades, shaft/rotor, nozzles, inlet guide lanes, disks, and casings. Then we used discounted cash flow (DCF) analysis to calculate the minimum sustainable price (MSP). MSP is the minimum price that a company must sell its product for in order to pay back the capital and operating expenses during the plant lifetime (CEMAC, 2017). The results showed that MSP could highly vary between 893 dollar/kW and 30 dollar/kW based on turbine size, standardization and volume of manufacturing. The analysis also showed that the economy of scale applies both to the size of the turbine and the number

Natural gas turbine topping for the iris reactor

International Nuclear Information System (INIS)

Oriani, L.; Lombardi, C.; Paramonov, D.

2001-01-01

Nuclear power plant designs are typically characterized by high capital and low fuel costs, while the opposite is true for fossil power generation including the natural gas-fired gas turbine combined cycle currently favored by many utilities worldwide. This paper examines potential advantages of combining nuclear and fossil (natural gas) generation options in a single plant. Technical and economic feasibility and attractiveness of a gas turbine - nuclear reactor combined cycle where gas turbine exhaust is used to superheat saturated steam produced by a low power light water reactor are examined. It is shown that in a certain range of fuel and capital costs of nuclear and fossil options, the proposed cycle offers an immediate economic advantage over stand-alone plants resulting from higher efficiency of the nuclear plant. Additionally, the gas turbine topping will result in higher fuel flexibility without the economic penalty typically associated with nuclear power. (author)

Natural gas turbine topping for the iris reactor

Energy Technology Data Exchange (ETDEWEB)

Oriani, L.; Lombardi, C. [Politecnico di Milano, Milan (Italy); Paramonov, D. [Westinghouse Electric Corp., LLC, Pittsburgh, PA (United States)

2001-07-01

Nuclear power plant designs are typically characterized by high capital and low fuel costs, while the opposite is true for fossil power generation including the natural gas-fired gas turbine combined cycle currently favored by many utilities worldwide. This paper examines potential advantages of combining nuclear and fossil (natural gas) generation options in a single plant. Technical and economic feasibility and attractiveness of a gas turbine - nuclear reactor combined cycle where gas turbine exhaust is used to superheat saturated steam produced by a low power light water reactor are examined. It is shown that in a certain range of fuel and capital costs of nuclear and fossil options, the proposed cycle offers an immediate economic advantage over stand-alone plants resulting from higher efficiency of the nuclear plant. Additionally, the gas turbine topping will result in higher fuel flexibility without the economic penalty typically associated with nuclear power. (author)

Using machine learning to predict wind turbine power output

International Nuclear Information System (INIS)

Clifton, A; Kilcher, L; Lundquist, J K; Fleming, P

2013-01-01

Wind turbine power output is known to be a strong function of wind speed, but is also affected by turbulence and shear. In this work, new aerostructural simulations of a generic 1.5 MW turbine are used to rank atmospheric influences on power output. Most significant is the hub height wind speed, followed by hub height turbulence intensity and then wind speed shear across the rotor disk. These simulation data are used to train regression trees that predict the turbine response for any combination of wind speed, turbulence intensity, and wind shear that might be expected at a turbine site. For a randomly selected atmospheric condition, the accuracy of the regression tree power predictions is three times higher than that from the traditional power curve methodology. The regression tree method can also be applied to turbine test data and used to predict turbine performance at a new site. No new data are required in comparison to the data that are usually collected for a wind resource assessment. Implementing the method requires turbine manufacturers to create a turbine regression tree model from test site data. Such an approach could significantly reduce bias in power predictions that arise because of the different turbulence and shear at the new site, compared to the test site. (letter)

Gas turbine

International Nuclear Information System (INIS)

Yang, Ok Ryong

2004-01-01

This book introduces gas turbine cycle explaining general thing of gas turbine, full gas turbine cycle, Ericson cycle and Brayton cycle, practical gas turbine cycle without pressure loss, multiaxial type gas turbine cycle and special gas turbine cycle, application of basic theory on a study on suction-cooling gas turbine cycle with turbo-refrigerating machine using the bleed air, and general performance characteristics of the suction-cooling gas turbine cycle combined with absorption-type refrigerating machine.

Closed Brayton cycle power conversion systems for nuclear reactors :

Energy Technology Data Exchange (ETDEWEB)

Wright, Steven A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vernon, Milton E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sanchez, Travis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2006-04-01

This report describes the results of a Sandia National Laboratories internally funded research program to study the coupling of nuclear reactors to gas dynamic Brayton power conversion systems. The research focused on developing integrated dynamic system models, fabricating a 10-30 kWe closed loop Brayton cycle, and validating these models by operating the Brayton test-loop. The work tasks were performed in three major areas. First, the system equations and dynamic models for reactors and Closed Brayton Cycle (CBC) systems were developed and implemented in SIMULINKTM. Within this effort, both steady state and dynamic system models for all the components (turbines, compressors, reactors, ducting, alternators, heat exchangers, and space based radiators) were developed and assembled into complete systems for gas cooled reactors, liquid metal reactors, and electrically heated simulators. Various control modules that use proportional-integral-differential (PID) feedback loops for the reactor and the power-conversion shaft speed were also developed and implemented. The simulation code is called RPCSIM (Reactor Power and Control Simulator). In the second task an open cycle commercially available Capstone C30 micro-turbine power generator was modified to provide a small inexpensive closed Brayton cycle test loop called the Sandia Brayton test-Loop (SBL-30). The Capstone gas-turbine unit housing was modified to permit the attachment of an electrical heater and a water cooled chiller to form a closed loop. The Capstone turbine, compressor, and alternator were used without modification. The Capstone systems nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system also were reused. The rotational speed of the turbo-machinery is controlled by adjusting the alternator load by using the electrical grid as the load bank. The SBL-30 test loop was operated at

Effective energy management by combining gas turbine cycles and forward osmosis desalination process

International Nuclear Information System (INIS)

Park, Min Young; Shin, Serin; Kim, Eung Soo

2015-01-01

Highlights: • Innovative gas turbine system and FO integrated system was proposed. • The feasibility of the integrated system was analyzed thermodynamically. • GOR of the FO–gas turbine system is 17% higher than those of MED and MSF. • Waste heat utilization of the suggested system is 85.7%. • Water production capacity of the suggested system is 3.5 times higher than the MSF–gas turbine system. - Abstract: In the recent years, attempts to improve the thermal efficiency of the gas turbine cycles have been made. In order to enhance the energy management of the gas turbine cycle, a new integration concept has been proposed; integration of gas turbine cycle and forward osmosis desalination process. The combination of the gas turbine cycle and the forward osmosis (FO) desalination process basically implies the coupling of the waste heat from the gas turbine cycle to the draw solute recovery system in the FO process which is the most energy consuming part of the whole FO process. By doing this, a strong system that is capable of producing water and electricity with very little waste heat can be achieved. The feasibility of this newly proposed system was analyzed using UNISIM program and the OLI property package. For the analysis, the thermolytic draw solutes which has been suggested by other research groups have been selected and studied. Sensitivity analysis was conducted on the integration system in order to understand and identify the key parameters of the integrated system. And the integrated system was further evaluated by comparing the gain output ratio (GOR) values with the conventional desalination technologies such as multi stage flash (MSF) and multi effect distillation (MED). The suggested integrated system was calculated to have a GOR of 14.8, while the MSF and MED when integrated to the gas turbine cycle showed GOR value of 12. It should also be noted that the energy utilization of the suggested integrated system is significantly higher by 27

Electric power generation and LNG evaporation with the aid of gas turbines within a closed-cycle process. [In German

Energy Technology Data Exchange (ETDEWEB)

Weber, D

1978-01-01

LNG, after being pumped to customary pipeline pressure, has a high working potential which can be technically utilized. Thus, in a modern large-size terminal, a power potential in the order of magnitude of several hundred MW is available. In the course of rising power prices the question becomes important if this potential continues to be wasted or if conversion to electric power is economical. In the proposed process the working fluid of a gas turbine plant with a closed circuit is cooled to -140/sup 0/C with LNG before entering the compressor and heated to +720/sup 0/C before entering the turbine by means of external heat gained by burning natural gas. With a 1 million m/sup 3//h throughput of LNG in its normal state, 237 MW of electric power can be generated with 53% efficiency with this simple circuit, which can be further developed. In a combination of closed gas turbine and diesel generator, almost 289 MW of electric power can be produced per 1 million m/sup 3//h LNG with an efficiency of 60%.

Technical and economic assessment of the integrated solar combined cycle power plants in Iran

International Nuclear Information System (INIS)

Soltani Hosseini, M.; Hosseini, R.; Valizadeh, G.H.

2002-01-01

Thermal efficiency, capacity factor, environmental considerations, investment cost, fuel and O and M costs are the main parameters for technical and economic assessment of solar power plants. This analysis has shown that the Integrated Solar Combined Cycle System with 67 MW e solar field(ISCCS-67) is the most suitable plan for the first solar power plant in Iran. The Levelized Energy Costs of combined cycle and ISCCS-67 power plants would be equal if 49 million dollars of ISCCS-67 capital cost supplied by the international environmental organizations such as Global Environmental Facilities and World Bank. This study shows that an ISCCS-67 saves 59 million dollars in fuel consumption and reduces about 2.4 million ton in CO 2 emission during 30 years operating period. Increasing of steam turbine capacity by 50%, and 4% improvement in overall efficiency are other advantages of iSCCS-67 power plant. The LEC of ISCCS-67 is 10% and so 33% lower than the combined cycle and gas turbine, respectively, at the same capacity factor with consideration of environmental costs

A Combined High and Low Cycle Fatigue Model for Life Prediction of Turbine Blades

Directory of Open Access Journals (Sweden)

Shun-Peng Zhu

2017-06-01

Full Text Available Combined high and low cycle fatigue (CCF generally induces the failure of aircraft gas turbine attachments. Based on the aero-engine load spectrum, accurate assessment of fatigue damage due to the interaction of high cycle fatigue (HCF resulting from high frequency vibrations and low cycle fatigue (LCF from ground-air-ground engine cycles is of critical importance for ensuring structural integrity of engine components, like turbine blades. In this paper, the influence of combined damage accumulation on the expected CCF life are investigated for turbine blades. The CCF behavior of a turbine blade is usually studied by testing with four load-controlled parameters, including high cycle stress amplitude and frequency, and low cycle stress amplitude and frequency. According to this, a new damage accumulation model is proposed based on Miner’s rule to consider the coupled damage due to HCF-LCF interaction by introducing the four load parameters. Five experimental datasets of turbine blade alloys and turbine blades were introduced for model validation and comparison between the proposed Miner, Manson-Halford, and Trufyakov-Kovalchuk models. Results show that the proposed model provides more accurate predictions than others with lower mean and standard deviation values of model prediction errors.

Maintenance management of gas turbine power plant systems ...

African Journals Online (AJOL)

Given the abundant availability of gas and the significant installed capacity of the electricity from Gas Turbine Power Systems; effective maintenance of Gas Turbine Power Plants in Nigeria could be the panacea for achieving regular power generation and supply. The study identified environmental impact on the machines, ...

Power Electronics for the Next Generation Wind Turbine System

DEFF Research Database (Denmark)

Ma, Ke

generation unit, are becoming crucial in the wind turbine system. The objective of this project is to study the power electronics technology used for the next generation wind turbines. Some emerging challenges as well as potentials like the cost of energy and reliability are going to be addressed. First...... conversion is pushed to multi-MW level with high power density requirement. It has also been revealed that thermal stress in the power semiconductors is closely related to many determining factors in the wind power application like the reliability, cost, power density, etc. therefore it is an important......The wind power generation has been steadily growing both for the total installed capacity and for the individual turbine size. Due to much more significant impacts to the power grid, the power electronics, which can change the behavior of wind turbines from an unregulated power source to an active...

Variable geometry gas turbines for improving the part-load performance of marine combined cycles - Gas turbine performance

DEFF Research Database (Denmark)

Haglind, Fredrik

2010-01-01

The part-load performance of gas and steam turbine combined cycles intended for naval use is of great importance, and it is influenced by the gas turbine configuration and load control strategy. This paper is aimed at quantifying the effects of variable geometry on the gas turbine part...... of various components within gas turbines. Two different gas turbine configurations are studied, a two-shaft aero-derivative configuration and a single-shaft industrial configuration. When both gas turbine configurations are running in part-load using fuel flow control, the results indicate better part......-load performance for the two-shaft gas turbine. Reducing the load this way is accompanied by a much larger decrease in exhaust gas temperature for the single-shaft gas turbine than for the two-shaft configuration. As used here, the results suggest that variable geometry generally deteriorates the gas turbine part...

Monitoring fatigue loads on wind turbines using cycle counting data acquisition systems

Energy Technology Data Exchange (ETDEWEB)

Soeker, H; Seifert, H [Deutsches Windenergie-Institut (Germany); Fragoulis, A; Vionis, P; Foussekis, D [Center for Renewable Energy Sources (Greece); Dahlberg, J A; Poppen, M [The Aeronautical Research Institue of Sweden (Sweden)

1996-09-01

As in any industrial application, the duration of a wind turbine`s life is a key parameter for the evaluation of its economic potential. Assuming a service life of 20 years, components of the turbine have to withstand a number of load cycles of up to 10{sup 8}. Such numbers of load cycles impose high demands on the fatigue characteristics of both, the used materials and the design. Nevertheless, fatigue loading of wind turbine components still remains a parameter of high uncertainty in the design of wind turbines. The specific features of these fatigue loads can be expected to vary with the type of turbine and the site of operation. In order to ensure the reliability of the next generation of larger scale wind turbines improved load assumptions will be of vital importance. Within the scope of the presented research program DEWI, C.R.E.S. and FFA monitored fatigue loads of serial produced wind turbines by means of a monitoring method that uses on-line cycle counting techniques. The blade root bending moments of two pitch controlled, variable speed wind turbines operating in the Hamswehrum wind farm, and also that of a stall controlled, fixed speed wind turbine operating in CRES` complex terrain test site, were measured by DEWI and CRES. In parallel FFA used their database of time series measurements of blade root bending moments on a stall controlled, fixed speed turbine at Alsvik Windfarm in order to derive semi-empirical fatigue load data. The experience gained from application of the on-line measurement technique is discussed with respect to performance, data quality, reliability and cost effectiveness. Investigations on the effects of wind farm and complex terrain operation on the fatigue loads of wind turbine rotor blades are presented. (au)

Gas-turbine industry prepares to become base-load supplier

International Nuclear Information System (INIS)

Hansen, T.

1996-01-01

Gas-turbine technology has entered a new era; the simple-cycle units of yesterday are making room for new, highly sophisticated combined-cycle units. In July 1949, the first U.S. commercial power generation gas turbine was installed at Oklahoma Gas and Electric Co.'s Belle Isle Station. This unit was a General Electric (GE) MS3000 heavy-duty gas turbine rated at 3,5000 kW. In 1994, more than 900 gas turbines totaling over 33,000 MW were ordered worldwide, according to Power-Data Group, LaJolla, Calif. These figures show just how far gas turbines have come in less than 50 years. Today, simple-cycle units rated at up to 150 MW (with efficiencies around 35 percent) and combined-cycle units rated at over 200 MW (approaching 60-percent efficiency) are up and running

Optimization of the triple-pressure combined cycle power plant

Directory of Open Access Journals (Sweden)

Alus Muammer

2012-01-01

Full Text Available The aim of this work was to develop a new system for optimization of parameters for combined cycle power plants (CCGTs with triple-pressure heat recovery steam generator (HRSG. Thermodynamic and thermoeconomic optimizations were carried out. The objective of the thermodynamic optimization is to enhance the efficiency of the CCGTs and to maximize the power production in the steam cycle (steam turbine gross power. Improvement of the efficiency of the CCGT plants is achieved through optimization of the operating parameters: temperature difference between the gas and steam (pinch point P.P. and the steam pressure in the HRSG. The objective of the thermoeconomic optimization is to minimize the production costs per unit of the generated electricity. Defining the optimal P.P. was the first step in the optimization procedure. Then, through the developed optimization process, other optimal operating parameters (steam pressure and condenser pressure were identified. The developed system was demonstrated for the case of a 282 MW CCGT power plant with a typical design for commercial combined cycle power plants. The optimized combined cycle was compared with the regular CCGT plant.

Effect of adoption of gas turbine in oil refinery

Energy Technology Data Exchange (ETDEWEB)

Tamai, Hiroto

1988-08-01

With progress in energy saving, and increase in automation in facilities, the dependence on electric power increases relative steam power. Further in order to reduce the production cost, the adoption of gas turbine combined cycle system, mainly aimed at power generation, is considered to be most suitable. This adoption, accompanied with the utilization of refinery offgas, dresults in a reduction in unit power generation cost, by increasing the ratio of domestic power generation. The gas turbine using deethanizing tower offgas as main fuel and butane as auxillary fuel, the combined cycle system, where steam produced from the turbine waste heat boiler drives the existing back pressure turbine, was constituted. The generator is 118 kVA in capacity. Against the maximum power demand being 16,500 kWh in the oil refinery, the obtainment of 11,000 kWh by the gas turbine and 2,500 kWh by the back pressure turbine was assured, with a considerable lowering in power to be purchased. (7 figs, 1 tab, 1 ref)

Demand of the power industry of Russia for gas turbines: the current state and prospects

Science.gov (United States)

Filippov, S. P.; Dil'man, M. D.; Ionov, M. S.

2017-11-01

The use of gas-turbine plants (GTPs) in the power industry of Russia is analyzed. Attention is paid to microturbines and low-, medium-, high-, and superhigh-power GTPs. The efficiency of the gas-turbine plants of domestic and foreign manufacture is compared. The actual values of the installed capacity utilization factor and the corresponding efficiency values are calculated for most GTPs operating in the country. The long-term demand of the country's electric power industry for GTPs for the period until 2040 is determined. The estimates have been obtained for three basic applications of the gas turbines, viz., for replacement of the GTPs that have exhausted their lifetime, replacement of outdated gas-turbine plants at gas-and-oilburning power plants, and construction of new thermal power plants to cover the anticipated growing demand for electric power. According to the findings of the research, the main item in the structure of the demand for GTPs will be their use to replace the decommissioned steam-turbine plants, predominantly those integrated into combined-cycle plants. The priority of the reconstruction of the thermal power plants in operation over the construction of new ones is determined by the large excess of accumulated installed capacities in the country and considerable savings on capital costs using production sites with completed infrastructure. It is established that medium- and high-power GTPs will be the most in-demand plants in the electric power industry. The demand for low-power GTPs will increase at high rates. The demand for microturbines is expected to be rather great. The demand for superhigh-power plants will become quantitatively significant after 2025 and grow rapidly afterwards. The necessity of accelerated development of competitive domestic GTPs with a wide range of capacities and mastering of their series manufacture as well as production of licensed gas turbines at a high production localization level on the territory of the country

Losses Analysis of Different Grounding Schemes for Transformer-less Wind Turbine with Full-Scale Power Converter

DEFF Research Database (Denmark)

Sztykiel, Michal; Teodorescu, Remus; Munk-Nielsen, Stig

2013-01-01

Following work examines IGBT power loss and temperature distribution with regard to specific grounding method for the future concept of transformer-less offshore wind turbine. Analysis is performed via steady-state IGBT power loss estimator, which is made based on averaging of repetitive pulse...... cycles. Obtained results are validated with the experimental test set-up consisting of high power IGBTs....

Evaporative gas turbine cycles. A thermodynamic evaluation of their potential

Energy Technology Data Exchange (ETDEWEB)

Rosen, P M

1993-03-01

The report presents a systematic method of thermodynamically evaluating different gas turbine cycles, treating the working fluids as ideal gases (c{sub p}=c{sub p}(T)). All models used to simulate different components in the cycles are presented in the report in detail and then connected in a computer program fully developed by the author. The report focuses on the theme of evaporative gas turbine cycles, in which low level heat is used to evaporate water into the compressed air stream between the compressor and recuperator. This leads to efficiency levels close to a comparable combined cycle but without the steam bottoming cycle. A parametric analysis has been conducted with the aim of deciding the best configuration of an evaporative cycle both for an uncooled expander and for a cooled expander. The model proposed to simulate the cooled expander is a combination between two existing models. (121 refs., 35 figs.,).

Gas turbines and operation of gas turbines 2011; Gasturbinen und Gasturbinenbetrieb 2011

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

Within the VGB Conference at 11th and 12th May, 2011 in Offenbach/Main (Federal Republic of Germany), the following lectures were held: (1) The future of high temperature gas turbines in power plants (Konrad Vogeler); (2) Development of reliable thermal barrier coatings for high-loaded turbine and combustor parts (Hans-Peter Bossmann); (3) CCPP Irsching 4 with gas turbine SGT5-8000H, on the way to 60 % CC efficiency (Willibald Fischer); (4) First test results of MAN's new 6 MW gas turbine (Markus Beukenberg); (5) Design characteristics and key thermodynamic parameters of the recuperated 4 MW solar turbines Mercury 50 gas turbines: - Economics and environmental feasibility, - operating experience in combined cycle applications with recuperation (Ulrich Stang); (6) Medium size gas turbines - OEM concept for continued reduction of life cycle costs (Vladimir Navrotsky); (7) Fracture mechanical analysis on fatigue failures of gas turbine components: - Root cause analysis - fracture mechanics - stress corrosion cracking - examples of failure analysis (Peter Verstraete); (8) The effectiveness of blade superalloy reheat treatment (Michael Wood); (9) An innovative combustion technology for high efficient gas turbines (Christian Oliver Paschereit); (10) Damping of thermo-acoustic vibrations in gas turbine combustion chambers (Sermed Sadig); (11) Alstom GT13E2 combustor upgrade for Vattenfalls Berlin Mitte combined heat and power plant (Klaus Doebbeling); (12) Optimisation of air inlet filtration for dust, rain and humidity (Heiko Manstein); (13) Life cycle cost reduction through high efficiency membrane based air intake filters (Helmut Krah); (14) Status and impact of national, European and international standardization on GT plants; GT standardizing status quo? (Gerd Weber); (15) Technical and thermodynamic aspects of compresssed air energy storage (Peter Radgen); (16) Requirements on the gas turbine in the course of time - intelligent OEM-concepts to ensure reliable

Energy Conversion Advanced Heat Transport Loop and Power Cycle

Energy Technology Data Exchange (ETDEWEB)

Oh, C. H.

2006-08-01

The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to various

Wind turbine power stations

International Nuclear Information System (INIS)

Anon.

1992-11-01

The Countryside Council for Wales (CCW's) policy on wind turbine power stations needs to be read in the context of CCW's document Energy:Policy and perspectives for the Welsh countryside. This identifies four levels of action aimed at reducing emission of gases which contribute towards the risk of global warming and gases which cause acid deposition. These are: the need for investment in energy efficiency; the need for investment in conventional power generation in order to meet the highest environmental standards; the need for investment in renewable energy; and the need to use land use transportation policies and decisions to ensure energy efficiency and energy conservation. CCW views wind turbine power stations, along with other renewable energy systems, within this framework. CCW's policy is to welcome the exploitation of renewable energy sources as an element in a complete and environmentally sensitive energy policy, subject to the Environmental Assessment of individual schemes and monitoring of the long-term impact of the various technologies involved. (Author)

Power Performance Test Report for the SWIFT Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Mendoza, I.; Hur, J.

2012-12-01

This report summarizes the results of a power performance test that NREL conducted on the SWIFT wind turbine. This test was conducted in accordance with the International Electrotechnical Commission's (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. However, because the SWIFT is a small turbine as defined by IEC, NREL also followed Annex H that applies to small wind turbines. In these summary results, wind speed is normalized to sea-level air density.

Development and performance measurement of micro-power pack using micro-gas turbine driven automotive alternators

International Nuclear Information System (INIS)

Sim, Kyuho; Koo, Bonjin; Kim, Chang Ho; Kim, Tae Ho

2013-01-01

Highlights: ► We develop micro-power pack using automotive alternator and micro-gas turbine. ► We measure rotordynamic and power generation performance of micro-power pack. ► Micro-power pack shows dramatic increases in mass and volumetric power densities. ► Test results assure feasibility of micro-power pack for electric vehicles. -- Abstract: This paper presents the development of a micro-power pack using automotive alternators powered by a micro-gas turbine (MGT) to recharge battery packs, in particular for electric vehicles (EVs). The thermodynamic efficiency for the MGT with the power turbine is estimated from a simple Brayton cycle analysis. The rotordynamic and power generation performance of the MGT driven alternator was measured during a series of experiments under electrical no-loading and loading conditions, and with belt-pulley and flexible bellows couplings. The flexible coupling showed superior rotordynamic and power generation performance than the belt coupling due to the enhanced alignment of the alternator rotor and the reduced mechanical frictions. Furthermore, the micro-power pack showed dramatic increases in the mass and volumetric power densities by ∼4 times and ∼5 times, respectively, compared with those of a commercial diesel generator with similar power level. As a result, this paper assures the feasibility of the light-weight micro-power pack using a MGT and automotive alternators for EVs.

Transient power coefficients for a two-blade Savonius wind turbine

Energy Technology Data Exchange (ETDEWEB)

Pope, K.; Naterer, G. [Univ. of Ontario Inst. of Technology, Oshawa, ON (Canada). Faculty of Engineering and Applied Science

2010-07-01

The wind power industry had a 29 percent growth rate in installed capacity in 2008, and technological advances are helping to speed up growth by significantly increasing wind turbine power yields. While the majority of the industry's growth has come from large horizontal axis wind turbine installations, small wind turbines can also be used in a wide variety of applications. This study predicted the transient power coefficient for a Savonius vertical axis wind turbine (VAWT) wind turbine with 2 blades. The turbine's flow field was used to analyze pressure distribution along the rotor blades in relation to the momentum, lift, and drag forces on the rotor surfaces. The integral force balance was used to predict the transient torque and power output of the turbine. The study examined the implications of the addition of a second blade on the model's ability to predict transient power outputs. Computational fluid dynamics (CFD) programs were used to verify that the formulation can be used to accurately predict the transient power coefficients of VAWTs with Savonius blades. 11 refs., 1 tab., 6 figs.

Power generation from a 7700C heat source by means of a main steam cycle, a topping closed gas cycle and a ammonia bottoming cycle

International Nuclear Information System (INIS)

Tilliette, Z.P.

1981-03-01

For power generation, steam cycles make an efficient use of medium temperature heat sources. They can be adapted to dry cooling, higher power ratings and output increase in winter by addition of an ammonia bottoming cycle. Active development is carried out in this field by 'Electricite de France'. As far as heat sources at higher temperatures are concerned, particularly related to coal-fired or nuclear power plants, a more efficient way of converting energy is at first to expand a hot working fluid through a gas turbine. It is shown in this paper that a satisfactory result, for heat sources of about 770 0 C, is obtained with a topping closed gas cycle of moderate power rating, rejecting its waste heat into the main steam cycle. Attention has to be paid to this gas cycle waste heat recovery and to the coupling of the gas and steam cycles. This concept drastically reduces the importance of new technology components. The use and the significance of an ammonia bottoming cycle in this case are investigated

Closed-cycle gas turbine working fluids

International Nuclear Information System (INIS)

Lee, J.C.; Campbell, J. Jr.; Wright, D.E.

1981-01-01

Characteristic requirements of a closed-cycle gas turbine (CCGT) working fluid were identified and the effects of their thermodynamic and transport properties on the CCGT cycle performance, required heat exchanger surface area and metal operating temperature, cycle operating pressure levels, and the turbomachinery design were investigated. Material compatibility, thermal and chemical stability, safety, cost, and availability of the working fluid were also considered in the study. This paper also discusses CCGT working fluids utilizing mixtures of two or more pure gases. Some mixtures of gases exhibit pronounced synergetic effects on their characteristic properties including viscosity, thermal conductivity and Prandtl number, resulting in desirable heat transfer properties and high molecular weights. 21 refs

Comparison of wind turbines based on power curve analysis

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-02-01

In the study measured power curves for 46 wind turbines were analyzed with the purpose to establish the basis for a consistent comparison of the efficiency of the wind turbines. Emphasis is on wind turbines above 500 kW rated power, with power curves measured after 1994 according to international recommendations. The available power curves fulfilling these requirements were smoothened according to a procedure developed for the purpose in such a way that the smoothened power curves are equally representative as the measured curves. The resulting smoothened power curves are presented in a standardized format for the subsequent processing. Using wind turbine data from the power curve documentation the analysis results in curves for specific energy production (kWh/M{sup 2}/yr) versus specific rotor load (kW/M{sup 2}) for a range of mean wind speeds. On this basis generalized curves for specific annual energy production versus specific rotor load are established for a number of generalized wind turbine concepts. The 46 smoothened standardized power curves presented in the report, the procedure developed to establish them, and the results of the analysis based on them aim at providers of measured power curves as well as users of them including manufacturers, advisors and decision makers. (au)

A condenser for very high power steam turbines

International Nuclear Information System (INIS)

Gardey, Robert.

1973-01-01

The invention relates to a condenser for very high power steam turbines under the masonry-block supporting the low-pressure stages of the turbine, that condenser comprises two horizontal aligned water-tube bundles passing through the steam-exhaust sleeves of the low-pressure stages, on both sides of a common inlet water box. The invention can be applied in particular to the 1000-2000 MW turbines of light water nuclear power stations [fr

Molten salt fueled nuclear facility with steam-and gas turbine cycles of heat transformation

International Nuclear Information System (INIS)

Ananich, P.I.; Bunin, E.N.; Kazazyan, V.T.; Nemtsev, V.A.; Sikorin, S.N.

2001-01-01

The molten salt fueled nuclear facilities with fuel circulating in the primary circuit have a series of the potential advantages in comparison with the traditional thermal and fast reactors with solid fuel elements. These advantages are ensured by the possibility to receive effective neutron balance in the core, minimum margin reactivity, more deep fuel burnup, unbroken correctness of the fuel physical and chemical properties and by low prices of the fuel cycle. The neutron and thermal-physical calculations of the various variants of the MSFNF with steam-water and gas turbine power circuits and their technical and economical comparison are carried out in this article. Calculations of molten salt nuclear power plant with gas turbine power circuit have been carried out using chemically reacting working body ''nitrin'' (N304 + 1%NO). The molten salt fueled reactors with the thermal power near of 2300 MW with two fuel compositions have been considered. The base variant has been taken the design of NPP with VVER NP-1000 when comparing the results of the calculations. Its economical performances are presented in prices of 1990. The results of the calculations show that it is difficult to determine the advantages of any one of the variants considered in a unique fashion. But NPP with MSR possesses large reserves in the process of optimization of cycle and energy equipment parameters that can improve its technical and economical performances sufficiently. (author)

Theoretical Investigation For The Effect of Fuel Quality on Gas Turbine Power Plants

Science.gov (United States)

AbdulRazzak khudair, Omar; Alwan Abass, Khetam; Saadi Abed, Noor; Hussain Ali, Khalid; AbdulAziz, Saad; Chlaib Shaboot, Ali

2018-05-01

turbine, as a result decline of power and gas turbine power plant efficiency causing the drop in the level of electric generation. The fuel quality is found to be a strong function of specific fuel consumption and its effects on the power generation and the efficiency of the gas turbine power plants and hence, the cycle performance shifts towards favorable conditions.

An exergoeconomic investigation of waste heat recovery from the Gas Turbine-Modular Helium Reactor (GT-MHR) employing an ammonia–water power/cooling cycle

International Nuclear Information System (INIS)

Zare, V.; Mahmoudi, S.M.S.; Yari, M.

2013-01-01

A detailed exergoeconomic analysis is performed for a combined cycle in which the waste heat from the Gas Turbine-Modular Helium Reactor (GT-MHR) is recovered by an ammonia–water power/cooling cogeneration system. Parametric investigations are conducted to evaluate the effects of decision variables on the performances of the GT-MHR and combined cycles. The performances of these cycles are then optimized from the viewpoints of first law, second law and exergoeconomics. It is found that, combining the GT-MHR with ammonia–water cycle not only enhances the first and second law efficiencies of the GT-MHR, but also it improves the cycle performance from the exergoeconomic perspective. The results show that, when the optimization is based on the exergoeconomics, the unit cost of products is reduced by 5.4% in combining the two mentioned cycles. This is achieved with a just about 1% increase in total investment cost rate since the helium mass flow in the combined cycle is lower than that in the GT-MHR alone. - Highlights: • Application of exergetic cost theory to the combined GT-MHR/ammonia–water cycle. • Enhanced exergoeconomic performance for the combined cycle compared to the GT-MHR. • Comparable investment costs for the combined cycle and the GT-MHR alone

Bifuel coal-gas combined cycles

International Nuclear Information System (INIS)

Chmielniak, Tadeusz; Kotowicz, Janusz; Lyczko, Jacek

1997-01-01

This paper describes basic ways of realization of bi fuel cool-gas combined cycles. The criterion of classification of the systems specification is a joint of the gas pail with the steam part: a) The gas turbine flue gases are introduced into the steam boiler combustion chamber (the serial, hot wind box). b) Bypass of the beat exchangers at the steam turbine unit and/or the steam boiler, by use the waste heat exchangers, or waste boiler at the gas turbine unit (the parallel-coupled). c) The mixed, it's a combination of the two upper. The analysis of the parallel system has been specially presented. In derived formulas for the total efficiency of the bi fuel parallel combined cycle balance equations have been used. This formulas can be used for planning new combined cycle power plants and for modernization existing steam power plants. It was made a discussion about influence of the ratio the gas and the steam turbine electric power on the cycle efficiency in care of the full and the part load of the bi fuel combined cycle power plant. The various systems of the joint of the gas part with the steam part have been examined. The selected results of the calculations have been attached. The models and the numerical simulations have been based on data from the existing steam power plants and real gas turbine units. (Author)

Variability of the Wind Turbine Power Curve

Directory of Open Access Journals (Sweden)

Mahesh M. Bandi

2016-09-01

Full Text Available Wind turbine power curves are calibrated by turbine manufacturers under requirements stipulated by the International Electrotechnical Commission to provide a functional mapping between the mean wind speed v ¯ and the mean turbine power output P ¯ . Wind plant operators employ these power curves to estimate or forecast wind power generation under given wind conditions. However, it is general knowledge that wide variability exists in these mean calibration values. We first analyse how the standard deviation in wind speed σ v affects the mean P ¯ and the standard deviation σ P of wind power. We find that the magnitude of wind power fluctuations scales as the square of the mean wind speed. Using data from three planetary locations, we find that the wind speed standard deviation σ v systematically varies with mean wind speed v ¯ , and in some instances, follows a scaling of the form σ v = C × v ¯ α ; C being a constant and α a fractional power. We show that, when applicable, this scaling form provides a minimal parameter description of the power curve in terms of v ¯ alone. Wind data from different locations establishes that (in instances when this scaling exists the exponent α varies with location, owing to the influence of local environmental conditions on wind speed variability. Since manufacturer-calibrated power curves cannot account for variability influenced by local conditions, this variability translates to forecast uncertainty in power generation. We close with a proposal for operators to perform post-installation recalibration of their turbine power curves to account for the influence of local environmental factors on wind speed variability in order to reduce the uncertainty of wind power forecasts. Understanding the relationship between wind’s speed and its variability is likely to lead to lower costs for the integration of wind power into the electric grid.

Power Curve of the AWEC-60 wind turbine

International Nuclear Information System (INIS)

Avia, F.

1992-01-01

The experimental wind turbine AWEC-60 was developed to evaluate the possibilities of the Large Wind turbines, from the technical and economical point of view. The project was developed by a spanish-german group, integrated by Union Fenosa, Asinel, M.A.N. Neue Technologie and the Instituto de Energias Renovables from CIEMAT, starting the operation during the year 1990. In this paper, the obtention of the wind turbine power curve is presented, which has been obtained in agreement with the Recommended Practices for Wind Turbine Testing and Evaluation from the Executive Committee for the Research and Development on Wind Energy, of the International Energy Agency (AIE). Using the functioning data of the wind turbine correspondig to the first quarter of the year 1991, the power curves have been obtained, and the results have been compared with the curves measured in other similar Large wind turbines. (Author) 7 refs

Analysis of the behaviour of biofuel-fired gas turbine power plants

Directory of Open Access Journals (Sweden)

Escudero Marcos

2012-01-01

Full Text Available The utilisation of biofuels in gas turbines is a promising alternative to fossil fuels for power generation. It would lead to a significant reduction of CO2 emissions using an existing combustion technology, although considerable changes appear to be required and further technological development is necessary. The goal of this work is to conduct energy and exergy analyses of the behaviour of gas turbines fired with biogas, ethanol and synthesis gas (bio-syngas, compared with natural gas. The global energy transformation process (i.e., from biomass to electricity also has been studied. Furthermore, the potential reduction of CO2 emissions attained by the use of biofuels has been determined, after considering the restrictions regarding biomass availability. Two different simulation tools have been used to accomplish this work. The results suggest a high interest in, and the technical viability of, the use of Biomass Integrated Gasification Combined Cycle (BioIGCC systems for large scale power generation.

Clean coal technologies for gas turbines

Energy Technology Data Exchange (ETDEWEB)

Todd, D.M. [GE Industrial & Power Systems, Schenectady, NY (United States)

1994-12-31

The oil- and gas-fired turbine combined-cycle penetration of industrial and utility applications has escalated rapidly due to the lower cost, higher efficiency and demonstrated reliability of gas turbine equipment in combination with fuel economics. Gas turbine technology growth has renewed the interest in the use of coal and other solid fuels in combined cycles for electrical and thermal energy production to provide environmentally acceptable plants without extra cost. Four different types of systems utilizing the gas turbine advantages with solid fuel have been studied: direct coal combustion, combustor processing, fuel processing and indirect cycles. One of these, fuel processing (exemplified by coal gasification), is emerging as the superior process for broad scale commercialization at this time. Advances in gas turbine design, proven in operation above 200 MW, are establishing new levels of combined-cycle net plant efficiencies up to 55% and providing the potential for a significant shift to gas turbine solid fuel power plant technology. These new efficiencies can mitigate the losses involved in gasifying coal and other solid fuels, and economically provide the superior environmental performance required today. Based on demonstration of high baseload reliability for large combined cycles (98%) and the success of several demonstrations of Integrated Gasification Combined Cycle (IGCC) plants in the utility size range, it is apparent that many commercial IGCC plants will be sites in the late 1990s. This paper discusses different gas turbine systems for solid fuels while profiling available IGCC systems. The paper traces the IGCC option as it moved from the demonstration phase to the commercial phase and should now with planned future improvements, penetrate the solid fuel power generation market at a rapid pace.

Analysis of power curves of Danish and foreign wind turbines

International Nuclear Information System (INIS)

Petersen, H.

1995-12-01

This report describes an analysis of power curves for a number of wind turbines, 30 Danish and 17 foreign - European - wind turbines. The investigation is limited to wind turbines of 150 kW capacity and greater, and to wind turbines for which a power curve is available. The power curves are transformed into a common, uniform presentation in order to facilitate the succeeding treatment, which primarily is the calculation of the production of electrical energy yielded per year. From the known data of the wind turbine, equipped generator power and rotor area and the area swept by the blades, the specific electrical production is calculated in three terms: yield per square meter of rotor area, yield per kW generator power and yield per square meter and per kilowatt generator power. Based on these findings a number of comparisons are established, such as comparisons of conceptual designs and technical- economical evaluations. (au)

The effects of solarization on the performance of a gas turbine

Science.gov (United States)

Homann, Christiaan; van der Spuy, Johan; von Backström, Theodor

2016-05-01

Various hybrid solar gas turbine configurations exist. The Stellenbosch University Solar Power Thermodynamic (SUNSPOT) cycle consists of a heliostat field, solar receiver, primary Brayton gas turbine cycle, thermal storage and secondary Rankine steam cycle. This study investigates the effect of the solarization of a gas turbine on its performance and details the integration of a gas turbine into a solar power plant. A Rover 1S60 gas turbine was modelled in Flownex, a thermal-fluid system simulation and design code, and validated against a one-dimensional thermodynamic model at design input conditions. The performance map of a newly designed centrifugal compressor was created and implemented in Flownex. The effect of the improved compressor on the performance of the gas turbine was evident. The gas turbine cycle was expanded to incorporate different components of a CSP plant, such as a solar receiver and heliostat field. The solarized gas turbine model simulates the gas turbine performance when subjected to a typical variation in solar resource. Site conditions at the Helio100 solar field were investigated and the possibility of integrating a gas turbine within this system evaluated. Heat addition due to solar irradiation resulted in a decreased fuel consumption rate. The influence of the additional pressure drop over the solar receiver was evident as it leads to decreased net power output. The new compressor increased the overall performance of the gas turbine and compensated for pressure losses incurred by the addition of solar components. The simulated integration of the solarized gas turbine at Helio100 showed potential, although the solar irradiation is too little to run the gas turbine on solar heat alone. The simulation evaluates the feasibility of solarizing a gas turbine and predicts plant performance for such a turbine cycle.

Pitot-tube turbine as wind power plant

Energy Technology Data Exchange (ETDEWEB)

Naake, L

1978-10-19

The use of the Pitot tube turbine as a wind power station is an application of the well known Pitot tube with the turbines built into jet engines. The novelty of this invention lies in the combined nozzle and turbine unit, where the wind is caught in the funnel opening, is accelerated in the narrow flow zone and then acts on the turbine blades. Due to the acceleration, a greater torque is exerted on the turbine than in free air flow. The Pitot tube turbine consists of a casing with a turbine inside, which is fixed by guide vane supports to the casing and which contains one or two stage turbine blades and electrical generators. The whole structure with the rotor is set on a sub-frame and rotation is contained by control surfaces. The subframe can be used as a building.

Turbine Control Strategies for Wind Farm Power Optimization

DEFF Research Database (Denmark)

Mirzaei, Mahmood; Göçmen Bozkurt, Tuhfe; Giebel, Gregor

2015-01-01

In recent decades there has been increasing interest in green energies, of which wind energy is the most important one. In order to improve the competitiveness of the wind power plants, there are ongoing researches to decrease cost per energy unit and increase the efficiency of wind turbines...... and wind farms. One way of achieving these goals is to optimize the power generated by a wind farm. One optimization method is to choose appropriate operating points for the individual wind turbines in the farm. We have made three models of a wind farm based on three difference control strategies...... the generated power by changing the power reference of the individual wind turbines. We use the optimization setup to compare power production of the wind farm models. This paper shows that for the most frequent wind velocities (below and around the rated values), the generated powers of the wind farms...

Enhancement of LNG plant propane cycle through waste heat powered absorption cooling

International Nuclear Information System (INIS)

Rodgers, P.; Mortazavi, A.; Eveloy, V.; Al-Hashimi, S.; Hwang, Y.; Radermacher, R.

2012-01-01

In liquefied natural gas (LNG) plants utilizing sea water for process cooling, both the efficiency and production capacity of the propane cycle decrease with increasing sea water temperature. To address this issue, several propane cycle enhancement approaches are investigated in this study, which require minimal modification of the existing plant configuration. These approaches rely on the use of gas turbine waste heat powered water/lithium bromide absorption cooling to either (i) subcool propane after the propane cycle condenser, or (ii) reduce propane cycle condensing pressure through pre-cooling of condenser cooling water. In the second approach, two alternative methods of pre-cooling condenser cooling water are considered, which consist of an open sea water loop, and a closed fresh water loop. In addition for all cases, three candidate absorption chiller configurations are evaluated, namely single-effect, double-effect, and cascaded double- and single-effect chillers. The thermodynamic performance of each propane cycle enhancement scheme, integrated in an actual LNG plant in the Persian Gulf, is evaluated using actual plant operating data. Subcooling propane after the propane cycle condenser is found to improve propane cycle total coefficient of performance (COP T ) and cooling capacity by 13% and 23%, respectively. The necessary cooling load could be provided by either a single-effect, double-effect or cascaded and single- and double-effect absorption refrigeration cycle recovering waste heat from a single gas turbine operated at full load. Reducing propane condensing pressure using a closed fresh water condenser cooling loop is found result in propane cycle COP T and cooling capacity enhancements of 63% and 22%, respectively, but would require substantially higher capital investment than for propane subcooling, due to higher cooling load and thus higher waste heat requirements. Considering the present trend of short process enhancement payback periods in the

Promising Direction of Perfection of the Utilization Combine Cycle Gas Turbine Units

Directory of Open Access Journals (Sweden)

Gabdullina Albina I.

2017-01-01

Full Text Available Issues of improving the efficiency of combined cycle gas turbines (CCGT recovery type have been presented. Efficiency gas turbine plant reaches values of 45 % due to rise in temperature to a gas turbine to 1700 °C. Modern technologies for improving the cooling gas turbine components and reducing the excess air ratio leads to a further increase of the efficiency by 1-2 %. Based on research conducted at the Tomsk Polytechnic University, it shows that the CCGT efficiency can be increased by 2-3 % in the winter time due to the use of organic Rankine cycle, low-boiling substances, and air-cooled condensers (ACC. It is necessary to apply the waste heat recovery with condensation of water vapor from the flue gas, it will enhance the efficiency of the CCGT by 2-3 % to increase the efficiency of the heat recovery steam boiler (HRSB to 10-12 %. Replacing electric pumps gas turbine engine (GTE helps to reduce electricity consumption for auxiliary needs CCGT by 0.5-1.5 %. At the same time the heat of flue gas turbine engine may be useful used in HRSB, thus will increase the capacity and efficiency of the steam turbine.

Power turbine ventilation system

Science.gov (United States)

Wakeman, Thomas G. (Inventor); Brown, Richard W. (Inventor)

1991-01-01

Air control mechanism within a power turbine section of a gas turbine engine. The power turbine section includes a rotor and at least one variable pitch propulsor blade. The propulsor blade is coupled to and extends radially outwardly of the rotor. A first annular fairing is rotatable with the propulsor blade and interposed between the propulsor blade and the rotor. A second fairing is located longitudinally adjacent to the first fairing. The first fairing and the second fairing are differentially rotatable. The air control mechanism includes a platform fixedly coupled to a radially inner end of the propulsor blade. The platform is generally positioned in a first opening and a first fairing. The platform and the first fairing define an outer space. In a first position corresponding with a first propulsor blade pitch, the platform is substantially conformal with the first fairing. In a second position corresponding with the second propulsor blade pitch, an edge portion of the platform is displaced radially outwardly from the first fairing. When the blades are in the second position and rotating about the engine axis, the displacement of the edge portion with respect to the first fairing allows air to flow from the outer space to the annular cavity.

Analysis of oxygen-enhanced combustion of gas power cycle

Energy Technology Data Exchange (ETDEWEB)

Maidana, Cristiano Frandalozo; Carotenuto, Adriano; Schneider, Paulo Smith [Universidade Federal do Rio Grande do Sul (GESTE/UFRGS), Porto Alegre, RS (Brazil). Grupo de Estudos Termicos e Energeticos], E-mails: cristiano.maidana@ufrgs.br, pss@mecanica.ufrgs.br

2010-07-01

The majority of combustion processes use air as oxidant, roughly taken as 21% O{sub 2} and 79% N{sub 2}, by volume. In many cases, these processes can be enhanced by using an oxidant that contains higher proportion of O{sub 2} than in air. This is known as oxygen-enhanced combustion or OEC, and can bring important benefits like higher thermal efficiencies, lower exhaust gas volumes, higher heat transfer efficiency, reduction fuel consumption, reduced equipment costs and substantially pollutant emissions reduction. Within this scenario, this paper aims to investigate the influence of 21-30% oxygen concentration on the performance of a air-fired natural gas fueled power plant. This power plant operates under a Brayton cycle with models with the help of an air flow splitter after the compressor output in order to dose the oxygen rate of combustion and to keep the flue gas intake of the turbine at a prescribed temperature. Simulations shows that the enhancing of the oxidant stream reduced fuel consumption of about 10%, driven by higher adiabatic flame temperatures, which improves thermal and heat transfer efficiencies. A conclusion obtained is that the use of oxygen in higher proportions can be a challenge to retrofit existing air-fired natural gas power turbine cycles, because of the technological limitation of its materials with higher flame temperatures. (author)

Design optimisation of a hybrid solid oxide fuel cell and gas turbine power generation system

Energy Technology Data Exchange (ETDEWEB)

Williams, G.J.; Siddle, A.; Pointon, K.

2001-07-01

The objectives of the combined ALSTOM Power Technology and Advantica Technologies project are reported as: (a) to design a gas turbine (GT) unit compatible with a solid oxide fuel cell (SOFC) in a high efficiency power system and aimed at the Distributed Power application range of 1-20MW, and (b) to identify the main features and components of a 'Proof of Concept' hybrid unit of output around 0.1MW, based on existing or near-market technology. The study showed: (i) while the potential for high efficiency SOFC + GT hybrid cycles is clear, little effort has been put into the design of the gas turbine and some other components and (ii) there is room for commercial exploitation in the areas of both component manufacture and system supply.

Evaluation of different turbine concepts for wind power

Energy Technology Data Exchange (ETDEWEB)

Eriksson, Sandra; Bernhoff, Hans; Leijon, Mats [Swedish Centre for Renewable Electric Energy Conversion, Division for Electricity and Lightning Research, Box 534, 751 21 Uppsala (Sweden)

2008-06-15

Every year the number of installed wind power plants in the world increases. The horizontal axis wind turbine is the most common type of turbine but there exist other types. Here, three different wind turbines are considered; the horizontal axis wind turbine and two different concepts of vertical axis wind turbines; the Darrieus turbine and the H-rotor. This paper aims at making a comparative study of these three different wind turbines from the most important aspects including structural dynamics, control systems, maintenance, manufacturing and electrical equipment. A case study is presented where three different turbines are compared to each other. Furthermore, a study of blade areas for different turbines is presented. The vertical axis wind turbine appears to be advantageous to the horizontal axis wind turbine in several aspects. (author)

Actual characteristics study on HTR-10GT coupling with direct gas turbine cycle

International Nuclear Information System (INIS)

Peng Xuechuang; Zhu Shutang; Wang Jie

2005-01-01

Compared with a plant of steam turbine cycle, a HTGR plant with direct gas turbine cycle has a higher thermal efficiency. A lot of investigations on the characteristics of HTR-10GT, which is the reactor studying project of Tsinghua University, have been carried out, however, all of them are based on the theoretical Brayton Cycle which neglects many actual conditions, such as leakage, pressure loss and so on. For engineering practices, leakage is an unavoidable problem. The difference of the location and capacity of leakage will directly influence the working medium's thermoparameters and lead to fall of the cycle efficiency. The present study is focused on the performance of an actual Brayton cycle with practical conditions of leakage. The present study which based on building the physical and mathematical model of the leakage, aims to study the actual characteristics of the direct gas turbine circle. (authors)

Wind Turbine Power Curve Design for Optimal Power Generation in Wind Farms Considering Wake Effect

Directory of Open Access Journals (Sweden)

Jie Tian

2017-03-01

Full Text Available In modern wind farms, maximum power point tracking (MPPT is widely implemented. Using the MPPT method, each individual wind turbine is controlled by its pitch angle and tip speed ratio to generate the maximum active power. In a wind farm, the upstream wind turbine may cause power loss to its downstream wind turbines due to the wake effect. According to the wake model, downstream power loss is also determined by the pitch angle and tip speed ratio of the upstream wind turbine. By optimizing the pitch angle and tip speed ratio of each wind turbine, the total active power of the wind farm can be increased. In this paper, the optimal pitch angle and tip speed ratio are selected for each wind turbine by the exhausted search. Considering the estimation error of the wake model, a solution to implement the optimized pitch angle and tip speed ratio is proposed, which is to generate the optimal control curves for each individual wind turbine off-line. In typical wind farms with regular layout, based on the detailed analysis of the influence of pitch angle and tip speed ratio on the total active power of the wind farm by the exhausted search, the optimization is simplified with the reduced computation complexity. By using the optimized control curves, the annual energy production (AEP is increased by 1.03% compared to using the MPPT method in a case-study of a typical eighty-turbine wind farm.

Model based active power control of a wind turbine

DEFF Research Database (Denmark)

Mirzaei, Mahmood; Soltani, Mohsen; Poulsen, Niels Kjølstad

2014-01-01

in the electricity market that selling the reserve power is more profitable than producing with the full capacity. Therefore wind turbines can be down-regulated and sell the differential capacity as the reserve power. In this paper we suggest a model based approach to control wind turbines for active power reference...

Steam condensation process in a power production cycle and heat exchanger for it

International Nuclear Information System (INIS)

Tondeur, Gerard; Andro, Jean; Marjollet, Jacques; Pouderoux, Pierre.

1982-01-01

Steam condensation process in a power production cycle by expansion in turbines, characterized by the fact that this condensation is performed by the vaporization of a coolant with a vaporization temperature at atmospheric pressure lower than that of water, and that the vaporized coolant fluid is expanded in a turbine and then condensed by heat exchange with cold water being heated, while the liquefied coolant is recompressed and used for heat exchange with the steam to be condensed [fr

Power generation from wind turbines in a solar chimney

Energy Technology Data Exchange (ETDEWEB)

Foote, Tudor [Graduate Student, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States); Agarwal, Ramesh K. [William Palm Professor, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States)

2013-07-01

Recent studies have shown that shrouded wind turbines can generate greater power compared to bare turbines. A solar chimney generates an upward draft of wind inside a tower and a shroud around the wind turbine. There are numerous empty silos on farms in the U.S. that can be converted to solar chimneys with minor modifications at modest cost. The objective of this study is to determine the potential of these silos/chimneys for generating wind power. The study is conducted through analytical/computational approach by employing the commercial Computational Fluid Dynamics (CFD) software. Computations are performed for five different geometric configurations consisting of a turbine, a cylindrical silo, and/or a venturi and/or a diffuser using the dimensions of typical silos and assuming Class 3 wind velocity. The incompressible Navier-Stokes equations with the Boussinesq approximation and a two equation realizable {kappa}-{epsilon} model are employed in the calculations, and the turbine is modeled as an actuator disk. The power coefficient (Cp) and generated power are calculated for the five cases. Consistent with recent literature, it was found that the silos with diffusers increase the Cp beyond Betz’s limit significantly and thus the generated power. It should be noted that Cp is calculated by normalizing it by the turbine area swept by the wind. This study shows the potential of using abandoned silos in the mid-west and other parts of the country for localized wind power generation.

Passive residual energy utilization system in thermal cycles on water-cooled power reactors

International Nuclear Information System (INIS)

Placco, Guilherme M.; Guimaraes, Lamartine N.F.; Santos, Rubens S. dos

2013-01-01

This work presents a concept of a residual energy utilization in nuclear plants thermal cycles. After taking notice of the causes of the Fukushima nuclear plant accident, an idea arose to adapt a passive thermal circuit as part of the ECCS (Emergency Core Cooling System). One of the research topics of IEAv (Institute for Advanced Studies), as part of the heat conversion of a space nuclear power system is a passive multi fluid turbine. One of the main characteristics of this device is its passive capability of staying inert and be brought to power at moments notice. During the first experiments and testing of this passive device, it became clear that any small amount of gas flow would generate power. Given that in the first stages of the Fukushima accident and even during the whole event there was plenty availability of steam flow that would be the proper condition to make the proposed system to work. This system starts in case of failure of the ECCS, including loss of site power, loss of diesel generators and loss of the battery power. This system does not requires electricity to run and will work with bleed steam. It will generate enough power to supply the plant safety system avoiding overheating of the reactor core produced by the decay heat. This passive system uses a modified Tesla type turbine. With the tests conducted until now, it is possible to ensure that the operation of this new turbine in a thermal cycle is very satisfactory and it performs as expected. (author)

Optimization of fog inlet air cooling system for combined cycle power plants using genetic algorithm

International Nuclear Information System (INIS)

Ehyaei, Mehdi A.; Tahani, Mojtaba; Ahmadi, Pouria; Esfandiari, Mohammad

2015-01-01

In this research paper, a comprehensive thermodynamic modeling of a combined cycle power plant is first conducted and the effects of gas turbine inlet fogging system on the first and second law efficiencies and net power outputs of combined cycle power plants are investigated. The combined cycle power plant (CCPP) considered for this study consist of a double pressure heat recovery steam generator (HRSG) to utilize the energy of exhaust leaving the gas turbine and produce superheated steam to generate electricity in the Rankine cycle. In order to enhance understanding of this research and come up with optimum performance assessment of the plant, a complete optimization is using a genetic algorithm conducted. In order to achieve this goal, a new objective function is defined for the system optimization including social cost of air pollution for the power generation systems. The objective function is based on the first law efficiency, energy cost and the external social cost of air pollution for an operational system. It is concluded that using inlet air cooling system for the CCPP system and its optimization results in an increase in the average output power, first and second law efficiencies by 17.24%, 3.6% and 3.5%, respectively, for three warm months of year. - Highlights: • To model the combined cycle power plant equipped with fog inlet air cooling method. • To conduct both exergy and economic analyses for better understanding. • To conduct a complete optimization using a genetic algorithm to determine the optimal design parameters of the system

Effect of turbine materials on power generation efficiency from free water vortex hydro power plant

International Nuclear Information System (INIS)

Sritram, P; Treedet, W; Suntivarakorn, R

2015-01-01

The objective of this research was to study the effect of turbine materials on power generation efficiency from the water free vortex hydro power plant made of steel and aluminium. These turbines consisted of five blades and were twisted with angles along the height of water. These blades were the maximum width of 45 cm. and height of 32 cm. These turbines were made and experimented for the water free vortex hydro power plant in the laboratory with the water flow rate of 0.68, 1.33, 1.61, 2.31, 2.96 and 3.63 m 3 /min and an electrical load of 20, 40, 60, 80 and 100 W respectively. The experimental results were calculated to find out the torque, electric power, and electricity production efficiency. From the experiment, the results showed that the maximum power generation efficiency of steel and aluminium turbine were 33.56% and 34.79% respectively. From the result at the maximum water flow rate of 3.63 m 3 /min, it was found that the torque value and electricity production efficiency of aluminium turbine was higher than that of steel turbine at the average of 8.4% and 8.14%, respectively. This result showed that light weight of water turbine can increase the torque and power generation efficiency. (paper)

A strategy for the economic optimization of combined cycle gas turbine power plants by taking advantage of useful thermodynamic relationships

International Nuclear Information System (INIS)

Godoy, E.; Benz, S.J.; Scenna, N.J.

2011-01-01

Optimal combined cycle gas turbine power plants characterized by minimum specific annual cost values are here determined for wide ranges of market conditions as given by the relative weights of capital investment and operative costs, by means of a non-linear mathematical programming model. On the other hand, as the technical optimization allows identifying trends in the system behavior and unveiling optimization opportunities, selected functional relationships are obtained as the thermodynamic optimal values of the decision variables are systematically linked to the ratio between the total heat transfer area and the net power production (here named as specific transfer area). A strategy for simplifying the resolution of the rigorous economic optimization problem of power plants is proposed based on the economic optima distinctive characteristics which describe the behavior of the decision variables of the power plant on its optima. Such approach results in a novel mathematical formulation shaped as a system of non-linear equations and additional constraints that is able to easily provide accurate estimations of the optimal values of the power plant design and operative variables. Research highlights: → We achieve relationships between power plants' economic and thermodynamic optima. → We achieve functionalities among thermodynamic optimal values of decision variables. → The rigorous optimization problem is reduced to a non-linear equations system. → Accurate estimations of power plants' design and operative variables are obtained.

Research and development of ceramic gas turbine

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Kazuo [National Aerospace Laboratory, Chofu-shi, Tokyo (Japan)

1993-12-31

The CO{sub 2} caused by the consumption of hydrocarbon fuel is one of the main gases which affect the global climate. In order to reduce the formation of CO{sub 2}, it is necessary to conserve energy as effectively as possible. Therefore the heat energy provided by the fuel should be utilized in multi-cascades. The energy at the high temperature should be used for the generation of electric power and the energy at low temperature could be used for making the steam and the hot water. The gas turbine is preferable for this purpose. The heat energy of exhaust gas can be reused more easily. The two systems are proposed by using the gas turbine as the high temperature stage. One is the cogeneration system and the other is the combined cycle. The former generates electric power by the gas turbine and make steam or hot water in the exhaust gas. The latter employs the gas turbine as the high temperature cycle and the steam turbine as the low temperature cycle.

Low temperature heat source for power generation: Exhaustive analysis of a carbon dioxide transcritical power cycle

International Nuclear Information System (INIS)

Velez, Fredy; Segovia, Jose; Chejne, Farid; Antolin, Gregorio; Quijano, Ana; Carmen Martin, M.

2011-01-01

The main results of a theoretical work on the use of a low temperature heat source for power generation through a carbon dioxide transcritical power cycle are reported in this paper. The procedure for analyzing the behaviour of the proposed cycle consisted in modifying the input pressure to the turbine from 66 bar, maintained constant each evaluated temperature (60 o C, 90 o C, 120 o C and 150 o C) until the net work was approximately zero. As a result, the maximum exergy efficiency was 50%, while the energy efficiencies obtained were 9.8%, 7.3%, 4.9% and 2.4% and the net specific work was 18.2 kJ/kg, 12.8 kJ/kg, 7.8 kJ/kg and 3.5 kJ/kg, respectively. Furthermore, the effect of the addition of an internal heat exchanger, which obviously supposed an increase in the efficiency, was analyzed. The analysis of the proposed system shows the viability of implementing this type of process as an energy alternative and/or strengthener of non-conventional energy sources in non-provided zones, or for increasing the energy efficiency in the industry. -- Highlights: → Energy and exergy analysis of a carbon dioxide transcritical power cycle is reported. → The effect of the inlet temperature to the turbine is evaluated. → Conditions of maximum efficiency and maximum net work are compared. → The inclusion of an IHX is also analysed.

Modelling and control of variable speed wind turbines for power system studies

DEFF Research Database (Denmark)

Michalke, Gabriele; Hansen, Anca Daniela

2010-01-01

and implemented in the power system simulation tool DIgSILENT. Important issues like the fault ride-through and grid support capabilities of these wind turbine concepts are addressed. The paper reveals that advanced control of variable speed wind turbines can improve power system stability. Finally......, it will be shown in the paper that wind parks consisting of variable speed wind turbines can help nearby connected fixed speed wind turbines to ride-through grid faults. Copyright © 2009 John Wiley & Sons, Ltd.......Modern wind turbines are predominantly variable speed wind turbines with power electronic interface. Emphasis in this paper is therefore on the modelling and control issues of these wind turbine concepts and especially on their impact on the power system. The models and control are developed...

Design of a wind turbine pitch angle controller for power system stabilisation

Energy Technology Data Exchange (ETDEWEB)

Jauch, Clemens; Soerensen, Poul [Risoe National Laboratory, Wind Energy Department, P.O. Box 49, DK-4000 Roskilde (Denmark); Islam, Syed M. [Department of Electrical and Computer Engineering, Curtin University of Technology, GPO Box U1987, Perth, WA 6845 (Australia); Bak Jensen, Birgitte [Institute of Energy Technology, Aalborg University, Pontoppidanstraede 101, DK-9220 Aalborg East (Denmark)

2007-11-15

The design of a PID pitch angle controller for a fixed speed active-stall wind turbine, using the root locus method is described in this paper. The purpose of this controller is to enable an active-stall wind turbine to perform power system stabilisation. For the purpose of controller design, the transfer function of the wind turbine is derived from the wind turbine's step response. The performance of this controller is tested by simulation, where the wind turbine model with its pitch angle controller is connected to a power system model. The power system model employed here is a realistic model of the North European power system. A short circuit fault on a busbar close to the wind turbine generator is simulated, and the dynamic responses of the system with and without the power system stabilisation of the wind turbines are presented. Simulations show that in most operating points the pitch controller can effectively contribute to power system stabilisation. (author)

Thermodynamic Analysis of Supplementary-Fired Gas Turbine Cycles

DEFF Research Database (Denmark)

Elmegaard, Brian; Henriksen, Ulrik Birk; Qvale, Einar Bjørn

2002-01-01

This paper presents an analysis of the possibilities for improving the efficiency of an indirectly biomass-fired gas turbine (IBFGT) by supplementary direct gas-firing. The supplementary firing may be based on natural gas, biogas, or pyrolysis gas. {The interest in this cycle arise from a recent...... demonstration of a two-stage gasification process through construction of several plants.} A preliminary analysis of the ideal recuperated Brayton cycle shows that for this cycle any supplementary firing will have a marginal efficiency of unity per extra unit of fuel. The same result is obtained...

Energy analysis and design of mixed CO{sub 2}/steam gas turbine cycles

Energy Technology Data Exchange (ETDEWEB)

Bram, S; De Ruyck, J [Vrije Universiteit Brussel, Brussels (Belgium). Dept. of Mechanics

1995-06-01

The capturing and disposal of CO{sub 2} from power plant exhaust gases is a possible route for reducing CO{sub 2} emissions. The present paper investigates the full recirculation of exhaust gases in a gas turbine cycle, combined with the injection of steam or water. Such recirculation leads to an exhaust gas with very high CO{sub 2} concentration (95% or more). Different regenerative cycle layouts are proposed and analyzed for efficiency, exergy destruction and technical feasibility. Pinch Technology methods are next applied to find the best configuration for heat regeneration and injection of water. From this analysis, dual pressure evaporation with water injection in the intercooler emerges as an interesting option. 3 refs., 2 figs., 1 tab.

Power engineering and turbine manufacture in Japan. Pt. 2

International Nuclear Information System (INIS)

Troyanovskij, B.M.

1995-01-01

Vapour turbines designs of thermal power plants, including those with increased steam parameters, nuclear power plants, vapour-gas facilities are considered. Data on efficiency of turbofacilities, turbinesmaterials, maneuverability characteristics, releases from gas-turbine facilities are presented. 21 refs.; 6 figs.; 5 tabs

Power curve of the AWEC-60 wind turbine

International Nuclear Information System (INIS)

Avia, F.

1992-01-01

The experimental wind turbine AWEC-60 was developed to evaluate the possibilities of the Large Wind turbines, from the technical and economical point of view. The project was developed by a spanish-german group, integrated by Union Fenosa, Asinel, M.A.N. Neue Technologie and the Instituto de Energias Renovables from CIEMAT, starting the operation during the year 1990. In this paper, the obtention of the wind turbine's power curve is presented, which has been obtained in agreement with the 'Recommended Practices for Wind Turbine Testing and Evaluation' from the Executive Committee for the Research and Development on Wind Energy, of the International Energy Agency (AIE). Using the functioning data of the wind turbine corresponding to the first quarter of the year 1991, the power curves have been obtained, and the results have been compared with the curves measured in other similar large windturbines. (author)

An Overview of Power Topologies for Micro-hydro Turbines

DEFF Research Database (Denmark)

Nababan, Sabar; Muljadi, E.; Blaabjerg, Frede

2012-01-01

This paper is an overview of different power topologies of micro-hydro turbines. The size of micro-hydro turbine is typically under 100kW. Conventional topologies of micro-hydro power are stand-alone operation used in rural electrical network in developing countries. Recently, many of micro-hydro...... power generations are connected to the distribution network through power electronics (PE). This turbines are operated in variable frequency operation to improve efficiency of micro-hydro power generation, improve the power quality, and ride through capability of the generation. In this paper our...... discussion is limited to the distributed generation. Like many other renewable energy sources, the objectives of micro-hydro power generation are to reduce the use of fossil fuel, to improve the reliability of the distribution system (grid), and to reduce the transmission losses. The overview described...

Power cycles with ammonia-water mixtures as working fluid

Energy Technology Data Exchange (ETDEWEB)

Thorin, Eva

2000-05-01

It is of great interest to improve the efficiency of power generating processes, i.e. to convert more of the energy in the heat source to power. This is favorable from an environmental point of view and can also be an economic advantage. To use an ammonia-water mixture instead of water as working fluid is a possible way to improve the efficiency of steam turbine processes. This thesis includes studies of power cycles with ammonia-water mixtures as working fluid utilizing different kinds of heat sources for power and heat generation. The thermophysical properties of the mixture are also studied. They play an important role in the calculations of the process performance and for the design of its components, such as heat exchangers. The studies concern thermodynamic simulations of processes in applications suitable for Swedish conditions. Available correlations for the thermophysical properties are compared and their influence on simulations and heat exchanger area predictions is investigated. Measurements of ammonia-water mixture viscosities using a vibrating wire viscometer are also described. The studies performed show that power cycles with ammonia-water mixtures as the working fluid are well suited for utilization of waste heat from industry and from gas engines. The ammonia-water power cycles can give up to 32 % more power in the industrial waste heat application and up to 54 % more power in the gas engine bottoming cycle application compared to a conventional Rankine steam cycle. However, ammonia-water power cycles in small direct-fired biomass-fueled cogeneration plants do not show better performance than a conventional Rankine steam cycle. When different correlations for the thermodynamic properties are used in simulations of a simple ammonia-water power cycle the difference in efficiency is not larger than 4 %, corresponding to about 1.3 percentage points. The differences in saturation properties between the correlations are, however, considerable at high

Studi Eksperimen Perbandingan Pengaruh Variasi Tekanan Inlet Turbin danVariasi Pembebanan Terhadap Karakteristik Turbin Pada Organic Rankine Cycle

Directory of Open Access Journals (Sweden)

Dwi Dharma Risqiawan

2013-12-01

Full Text Available Sistem pembangkit listrik telah berinovasi pada saat ini untuk tetap memenuhi kebutuhan akan ketersediaan listrik salah satunya dengan Organic Rankine Cycle (ORC. Sistem ini terdiri dari empat komponen utama yaitu evaporator, turbin, kondensor, dan pompa.Fluida kerja dipompa ke evaporator untuk membangkitkan uap lalu digunakan menggerakkan turbin.Uap hasil ekspansi turbin dikondensasi dan dialirkan oleh pompa kembali ke evaporator.Sistem ini mampu memanfaatkan sumber energi yang memiliki temperatur dan tekanan rendah untuk membangkitkan uap fluida organik. Penelitian ini dilakukan untuk mengevaluasi kinerja turbin pada sistem ORC dengan memvariasikan tekanan masuk turbin dan pembebanan dengan menggunakan R-123 sebagai fluida kerja .Pengambilan data dilakukan dengan memvariasikan tekanan masuk turbin pada setiap variasi pembebanan generator.Pengamatan dilakukan hanya pada turbin untuk mengetahui karakteristik turbin yang digunakan saat ini.Pengambilan data dilakukan dengan R-123 sebagai fluida kerja. Dari eksperimen didapatkan temperatur masuk dan keluar turbin,kecepatan putaran turbin dalam rpm, dan enthalpy dapat diketahui. Enthalpy digunakan untuk mengitung kerja yang dihasilkan turbin, efisiensi turbin dan efisiensi sudu turbin.Pada tekanan masuk turbin 8 bar dan beban 1000 Watt data dengan nilai terbaik didapatkan.Hasil perhitungan data didapatkan kerja yang dihasilkan turbin yang terbesar adalah 5,4 KW. Hasil lain yang dapat diketahui adalah efisiensi turbin tertinggi 88%. Efisiensi sudu turbin tertinggi yang terhitung adalah 42,9%.

Optimizing power plant cycling operations while reducing generating plant damage and costs

Energy Technology Data Exchange (ETDEWEB)

Lefton, S A; Besuner, P H; Grimsrud, P [Aptech Engineering Services, Inc., Sunnyvale, CA (United States); Bissel, A [Electric Supply Board, Dublin (Ireland)

1999-12-31

This presentation describes a method for analyzing, quantifying, and minimizing the total cost of fossil, combined cycle, and pumped hydro power plant cycling operation. The method has been developed, refined, and applied during engineering studies at some 160 units in the United States and 8 units at the Irish Electric Supply Board (ESB) generating system. The basic premise of these studies was that utilities are underestimating the cost of cycling operation. The studies showed that the cost of cycling conventional boiler/turbine fossil power plants can range from between $2,500 and $500,000 per start-stop cycle. It was found that utilities typically estimate these costs by factors of 3 to 30 below actual costs and, thus, often significantly underestimate their true cycling costs. Knowledge of the actual, or total, cost of cycling will reduce power production costs by enabling utilities to more accurately dispatch their units to manage unit life expectancies, maintenance strategies and reliability. Utility management responses to these costs are presented and utility cost savings have been demonstrated. (orig.) 7 refs.

Optimizing power plant cycling operations while reducing generating plant damage and costs

Energy Technology Data Exchange (ETDEWEB)

Lefton, S.A.; Besuner, P.H.; Grimsrud, P. [Aptech Engineering Services, Inc., Sunnyvale, CA (United States); Bissel, A. [Electric Supply Board, Dublin (Ireland)

1998-12-31

This presentation describes a method for analyzing, quantifying, and minimizing the total cost of fossil, combined cycle, and pumped hydro power plant cycling operation. The method has been developed, refined, and applied during engineering studies at some 160 units in the United States and 8 units at the Irish Electric Supply Board (ESB) generating system. The basic premise of these studies was that utilities are underestimating the cost of cycling operation. The studies showed that the cost of cycling conventional boiler/turbine fossil power plants can range from between $2,500 and $500,000 per start-stop cycle. It was found that utilities typically estimate these costs by factors of 3 to 30 below actual costs and, thus, often significantly underestimate their true cycling costs. Knowledge of the actual, or total, cost of cycling will reduce power production costs by enabling utilities to more accurately dispatch their units to manage unit life expectancies, maintenance strategies and reliability. Utility management responses to these costs are presented and utility cost savings have been demonstrated. (orig.) 7 refs.

Steam Turbine Control Valve Stiction Effect on Power System Stability

International Nuclear Information System (INIS)

Halimi, B.

2010-01-01

One of the most important problems in power system dynamic stability is low frequency oscillations. This kind of oscillation has significant effects on the stability and security of the power system. In some previous papers, a fact was introduced that a steam pressure continuous fluctuation in turbine steam inlet pipeline may lead to a kind of low frequency oscillation of power systems. Generally, in a power generation plant, steam turbine system composes of some main components, i.e. a boiler or steam generator, stop valves, control valves and turbines that are connected by piping. In the conventional system, the turbine system is composed with a lot of stop and control valves. The steam is provided by a boiler or steam generator. In an abnormal case, the stop valve shuts of the steal flow to the turbine. The steam flow to the turbine is regulated by controlling the control valves. The control valves are provided to regulate the flow of steam to the turbine for starting, increasing or decreasing the power, and also maintaining speed control with the turbine governor system. Unfortunately, the control valve has inherent static friction (stiction) nonlinearity characteristics. Industrial surveys indicated that about 20-30% of all control loops oscillate due to valve problem caused by this nonlinear characteristic. In this paper, steam turbine control valve stiction effect on power system oscillation is presented. To analyze the stiction characteristic effect, firstly a model of control valve and its stiction characteristic are derived by using Newton's laws. A complete tandem steam prime mover, including a speed governing system, a four-stage steam turbine, and a shaft with up to for masses is adopted to analyze the performance of the steam turbine. The governor system consists of some important parts, i.e. a proportional controller, speed relay, control valve with its stiction characteristic, and stem lift position of control valve controller. The steam turbine has

Analysing the Possible Ways for Short-Term Forcing Gas Turbine Engines in Auxiliary Power Unit

Directory of Open Access Journals (Sweden)

N. I. Trotskii

2016-01-01

Full Text Available Using a gas turbine energy unit as an example, the article discusses possible ways for forcing the short-term gas turbine engines (GTE. The introduction explains the need for forcing the air transport and marine GTE in specific driving conditions and offers the main methods. Then it analyzes the three main short-term forcing methods according to GTE power, namely: precompressor water injection, a short-term rise in temperature after the combustion chamber, and feeding an additional compressed air into combustion chamber from the reserve cylinders.The analysis of the water injection method to force a GTE presents the main provisions and calculation results of the cycle, as a function of engine power on the amount of water injected into compressor inlet. It is shown that with water injection into compressor inlet in an amount of 1% of the total airflow there is a 17% power increase in the compressor. It also lists the main implementation problems of this method and makes a comparison with the results of other studies on the water injection into compressor.Next, the article concerns the GTE short-term forcing method through the pre-turbine short-term increase in the gas temperature. The article presents the calculation results of the cycle as a function of the power and the fuel-flow rate on the gas temperature at the turbine inlet. It is shown that with increasing temperature by 80 degrees the engine power increases by 11.2% and requires 11% more fuel. In the analysis of this method arises an issue of thermal barrier coating on the blade surface. The article discusses the most common types of coatings and their main shortcomings. It lists the main challenges and some ways of their solving when using this method to implement the short-term forcing.The last method under consideration is GTE short-term forcing by feeding the compressed air into the combustion chamber from the additional reserve cylinders. It should be noted that this method is

Comparison of performances of full-speed turbine and half-speed turbine for nuclear power plants

International Nuclear Information System (INIS)

Wang Hu; Zhang Weihong; Zhang Qiang; Li Shaohua

2010-01-01

The steam turbines of nuclear power plants can be divided into the full-speed turbine and half-speed turbine. Different speed leads to differences in many aspects. Therefore, the rational speed is the key point in the selection of steam turbines. This paper contrasts the economy between the half-speed turbine and full-speed turbine, by calculating the relative internal efficiency of half-speed and full-speed steam turbines with the typical level of 1000 megawatt. At the same time, this paper also calculate the relative speed of high speed water drops in the last stage blade of half-speed turbine and full-speed turbine, to contrast the water erosion between the half-speed turbine and full-speed turbine. The results show that the relative internal efficiency of half-speed turbine is higher than that of the full-speed turbine, and that the security especially the ability of preventing water erosion of half-speed turbine is better than that of the full-speed turbine. (authors)

Power Properties of Two Interacting Wind Turbine Rotors

DEFF Research Database (Denmark)

Okulov, Valery; Mikkelsen, Robert Flemming; Sørensen, Jens Nørkær

2016-01-01

In the current experiments, two identical wind turbine models were placed in uniform flow conditions in a water flume. The initial flow in the flume was subject to a very low turbulence level, limiting the influence of external disturbances on the development of the inherent wake instability. Both....... The resulting power capacity has been studied and analyzed at different rotor positions and a range of tip speed ratios from 2 to 8 and a simple algebraic relationship between the velocity deficit in the wake of the front turbine and the power of the second turbine was found, when both rotors have the coaxial...

Power Properties of Two Interacting Wind Turbine Rotors

DEFF Research Database (Denmark)

Okulov, Valery; Mikkelsen, Robert Flemming; Sørensen, Jens Nørkær

2017-01-01

In the current experiments, two identical wind turbine models were placed in uniform flow conditions in a water flume. The initial flow in the flume was subject to a very low turbulence level, limiting the influence of external disturbances on the development of the inherent wake instability. Both....... The resulting power capacity has been studied and analyzed at different rotor positions and a range of tip-speed ratios from 2 to 8, and a simple algebraic relationship between the velocity deficit in the wake of the front turbine and the power of the second turbine was found, when both rotors have the coaxial...

Performance of a direct drive hydro turbine for wave power generation

Energy Technology Data Exchange (ETDEWEB)

Lee, Y-H; Kim, C-G [Division of Mechanical and Information Engineering, Korea Maritime University Dongsam-dong 1, Youngdo-ku, Busan, 606-791 (Korea, Republic of); Choi, Y-D; Kim, I-S [Department of Mechanical Engineering, Mokpo National University Muan-ro 560, Chunggye-myun, Jeonnam, 534-729 (Korea, Republic of); Hwang, Y-C, E-mail: lyh@hhu.ac.k [R and D Institute, Shinhan Precision Co. Ltd. Gomo-ri 313, Jinle-myun, Kimhae, 621-881 (Korea, Republic of)

2010-08-15

Clean and renewable energy technologies using ocean energy give us non-polluting alternatives to fossil-fueled power plants as a countermeasure against the global warming and growing demand for electrical energy. Among the ocean energy resources, wave power takes a growing interest because of its enormous amount of potential energy in the world. Therefore, various types of wave power system to capture the energy of ocean waves have been developed. However, suitable turbine type is not normalized yet because of relatively low efficiency of the turbine systems. The purpose of this study is to investigate the performance of a newly developed direct drive hydro turbine (DDT), which will be built in a caisson for wave power plant. Experiment and CFD analysis are conducted to clarify the turbine performance and internal flow characteristics. The results show that the DDT obtains fairly good turbine efficiency in both cases of with wave and no wave conditions. As the turbine performance is influenced considerably by the wave condition, designed point of the turbine should be determined according to the wave condition at an expected installation site. Most of the output power generates at the runner passage of the Stage 2.

Advanced LP turbine installation at 1300 MW nuclear power station Unterweser

International Nuclear Information System (INIS)

Jacobsen, G.; Oeynhausen, H.; Termuehlen, H.

1991-01-01

This paper reports on Preussen Elektra AG's Unterweser power plant. The steam turbine-generator features a disk-type LP turbine rotor design developed in the late 1960's to early 1970's. This rotor design has been installed in 19 nuclear power plants. The 47 rotors in these plants have been in operation for an average of almost 10 years. The design of the 1970 vintage nuclear LP turbine rotors was based on extensive experience gained with disk-type rotors of fossil turbines built in the 1950's. When EPRI reported about corrosion cracking in nuclear LP turbines, a program was initiated by Siemens/KWU as original steam turbine supplier to ultrasonically inspect all their disk-type rotors in nuclear power plats. Indications on one rotor disk in the Unterweser plant was found. This single event was the only one found out of 310 disks inspected in nuclear power plants

Power Electronics Converters for Wind Turbine Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Liserre, Marco; Ma, Ke

2012-01-01

The steady growth of installed wind power together with the upscaling of the single wind turbine power capability has pushed the research and development of power converters toward full-scale power conversion, lowered cost pr kW, increased power density, and also the need for higher reliability. ...

Turbine and its turbine control system of full scope simulator for Qinshan 300 MW Nuclear Power Unit

International Nuclear Information System (INIS)

Zhang Dongwei; Zhu Jinping

1996-01-01

The simulation for Qinshan 300 MW Nuclear Power Unit turbine and turbine control system is briefly introduced. The simulation system includes lube oil system, jacking oil pump system, turning gear system, turbine supervisor system and turbine control system. It not only correctly simulates the process of turbine normal start up, operation, and shut down, but also the response of turbine under the malfunction conditions

Numerical Investigation of Methane Combustion under Mixed Air-Steam Turbine Conditions

NARCIS (Netherlands)

Skevis, G.; Chrissanthopoulos, A.; Goussis, D.A.; Mastorakos, E.; Derksen, M.A.F.; Kok, Jacobus B.W.

2004-01-01

Lowering emissions from power generating gas turbines, while retaining efficiency and power output, constitutes a formidable task, both at fundamental and technical levels. Combined gas turbine cycles involving air humidification are particularly attractive, since they provide additional power with

Design of a wind turbine pitch angle controller for power system stabilisation

DEFF Research Database (Denmark)

Jauch, Clemens; Islam, S.M.; Sørensen, Poul Ejnar

2007-01-01

The design of a PID pitch angle controller for a fixed speed active-stall wind turbine, using the root locus method is described in this paper. The purpose of this controller is to enable an active-stall wind turbine to perform power system stabilisation. For the purpose of controller design......, the transfer function of the wind turbine is derived from the wind turbine's step response. The performance of this controller is tested by simulation, where the wind turbine model with its pitch angle controller is connected to a power system model. The power system model employed here is a realistic model...... of the North European power system. A short circuit fault on a busbar close to the wind turbine generator is simulated, and the dynamic responses of the system with and without the power system stabilisation of the wind turbines are presented. Simulations show that in most operating points the pitch controller...

Wind turbine power performance verification in complex terrain and wind farms

DEFF Research Database (Denmark)

Friis Pedersen, Troels; Gjerding, S.; Enevoldsen, P.

2002-01-01

is a power performance verification procedure for individual wind turbines. The third is a power performance measurement procedure of whole wind farms, and the fourth is a power performance measurement procedurefor non-grid (small) wind turbines. This report presents work that was made to support the basis......The IEC/EN 61400-12 Ed 1 standard for wind turbine power performance testing is being revised. The standard will be divided into four documents. The first one of these is more or less a revision of the existing document on power performance measurementson individual wind turbines. The second one...... then been investigated in more detail. The work has given rise to a range of conclusionsand recommendations regarding: guaranties on power curves in complex terrain; investors and bankers experience with verification of power curves; power performance in relation to regional correction curves for Denmark...

Hybrid anisotropic materials for wind power turbine blades

CERN Document Server

Golfman, Yosif

2012-01-01

Based on rapid technological developments in wind power, governments and energy corporations are aggressively investing in this natural resource. Illustrating some of the crucial new breakthroughs in structural design and application of wind energy generation machinery, Hybrid Anisotropic Materials for Wind Power Turbine Blades explores new automated, repeatable production techniques that expand the use of robotics and process controls. These practices are intended to ensure cheaper fabrication of less-defective anisotropic material composites used to manufacture power turbine blades. This boo

Dynamic wind turbine models in power system simulation tool

DEFF Research Database (Denmark)

Hansen, Anca D.; Iov, Florin; Sørensen, Poul

, connection of the wind turbine at different types of grid and storage systems. Different control strategies have been developed and implemented for these wind turbine concepts, their performance in normal or fault operation being assessed and discussed by means of simulations. The described control......This report presents a collection of models and control strategies developed and implemented in the power system simulation tool PowerFactory DIgSILENT for different wind turbine concepts. It is the second edition of Risø-R-1400(EN) and it gathers and describes a whole wind turbine model database...... of the interaction between the mechanical structure of the wind turbine and the electrical grid during different operational modes. The report provides thus a description of the wind turbines modelling, both at a component level and at a system level. The report contains both the description of DIgSILENT built...

Modernization of turbines in fossil and nuclear power plants

International Nuclear Information System (INIS)

Harig, T.; Oeynhausen, H.

2004-01-01

Steam turbine power plants have a big share in power generation world-wide. In view of their age structure, they offer the biggest potential for increasing power plant performance, availability and environmental protection. Modernisation and replacement of key components by improved components will reduce fuel consumption and improve power plant performance by higher capacity, higher power, shorter start-up and shutdown times, and reduced standstill times. Modern steam turbine bladings will result in further improvements without additional fuel consumption. (orig.)

Theoretical analysis of a transcritical power cycle for power generation from waste energy at low temperature heat source

International Nuclear Information System (INIS)

Vélez, Fredy; Chejne, Farid; Antolin, Gregorio; Quijano, Ana

2012-01-01

The present paper reports the results obtained on a carbon dioxide transcritical power cycle using an energy and exergy analysis. The procedure consisted of modifying the inlet pressure to the turbine from 66 bar, by means of the software HYSYS®, maintaining constant each evaluated turbine inlet temperature (60, 90, 120 and 150 °C) until the net work was approximately zero. As a result, an increase up to 25% for the exergy efficiency, and up to 300% for the energy efficiency are obtained when the inlet temperature to the turbine is risen from 60 to 150 °C. Consequently, the analysis shows the viability of implementing this process as alternative energy, because of the possibility to recovery energy from waste heat from industrial processes.

Saturated steam turbines for power reactors of WWER-type

International Nuclear Information System (INIS)

Czwiertnia, K.

1978-01-01

The publication deals with design problems of large turbines for saturated steam and with problem of output limitations of single shaft normal speed units. The possibility of unification of conventional and nuclear turbines, which creates the economic basis for production of both types of turbines by one manufacturer based on standarized elements and assemblies is underlined. As separate problems the distribution of nuclear district heating power systems are considered. The choice of heat diagram for district heating saturated steam turbines, the advantages of different diagrams and evaluaton for further development are presented. On this basis a program of unified turbines both condensing and district heating type suitable for Soviet reactors of WWER-440 and WWER-1000 type for planned development of nuclear power in Poland is proposed. (author)

Simulation of a heavy-duty diesel engine with electrical turbocompounding system using operating charts for turbocharger components and power turbine

International Nuclear Information System (INIS)

Katsanos, C.O.; Hountalas, D.T.; Zannis, T.C.

2013-01-01

Highlights: • A diesel model was developed using charts for turbocharger and power turbine. • The maximum value of bsfc improvement is 4.1% at 100% engine load. • The generated electric power ranges from 23 kW to 62 kW. • Turbocharger turbine efficiency decreases slightly with the power turbine speed. • Turbocompounding increases the average pressure value in the exhaust manifold. - Abstract: In diesel engines, approximately 30–40% of the energy supplied by the fuel is rejected to the ambience through exhaust gases. Therefore, there is a potentiality for further considerable increase of diesel engine efficiency with the utilization of exhaust gas heat and its conversion to mechanical or electrical energy. In the present study, the operational behavior of a heavy-duty (HD) diesel truck engine equipped with an electric turbocompounding system is examined on a theoretical basis. The electrical turbocompounding configuration comprised of a power turbine coupled to an electric generator, which is installed downstream to the turbocharger (T/C) turbine. A diesel engine simulation model has been developed using operating charts for both turbocharger and power turbine. A method for introducing the operating charts into the engine model is described thoroughly. A parametric analysis is conducted with the developed simulation tool, where the varying parameter is the rotational speed of power turbine shaft. In this study, the interaction between the power turbine and the turbocharged diesel engine is examined in detail. The effect of power turbine speed on T/C components efficiencies, power turbine efficiency, exhaust pressure and temperature, engine boost pressure and air to fuel ratio is evaluated. In addition, theoretical results for the potential impact of electrical turbocompounding on the generated electric power, net engine power and relative improvement of brake specific fuel consumption (bsfc) are provided. The critical evaluation of the theoretical

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 2: Advanced energy conversion systems. Part 1: Open-cycle gas turbines

Science.gov (United States)

Brown, D. H.; Corman, J. C.

1976-01-01

Ten energy conversion systems are defined and analyzed in terms of efficiency. These include: open-cycle gas turbine recuperative; open-cycle gas turbine; closed-cycle gas turbine; supercritical CO2 cycle; advanced steam cycle; liquid metal topping cycle; open-cycle MHD; closed-cycle inert gas MHD; closed-cycle liquid metal MHD; and fuel cells. Results are presented.

Cooperative wind turbine control for maximizing wind farm power using sequential convex programming

International Nuclear Information System (INIS)

Park, Jinkyoo; Law, Kincho H.

2015-01-01

Highlights: • The continuous wake model describes well the wake profile behind a wind turbine. • The wind farm power function describes well the power production of a wind farm. • Cooperative control increases the wind farm power efficiency by 7.3% in average. • SCP can be employed to efficiently optimize the control actions of wind turbines. - Abstract: This paper describes the use of a cooperative wind farm control approach to improve the power production of a wind farm. The power production by a downstream wind turbine can decrease significantly due to reduced wind speed caused by the upstream wind turbines, thereby lowering the overall wind farm power production efficiency. In spite of the interactions among the wind turbines, the conventional (greedy) wind turbine control strategy tries to maximize the power of each individual wind turbine by controlling its yaw angle, its blade pitch angle and its generator torque. To maximize the overall wind farm power production while taking the wake interference into account, this study employs a cooperative control strategy. We first derive the wind farm power as a differentiable function of the control actions for the wind turbines in a wind farm. The wind farm power function is then maximized using sequential convex programming (SCP) to determine the optimum coordinated control actions for the wind turbines. Using an example wind farm site and available wind data, we show how the cooperative control strategy improves the power production of the wind farm

Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase

International Nuclear Information System (INIS)

Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M.

2012-10-01

The present work is a continuation of the task: Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) in which the modeling of the vapor cycle of the nuclear power plant of Laguna Verde was realized with PEPSE code (Performance Evaluation of Power System Efficiencies). Once reached the conditions of nominal operation of extended power increase, operating both units to 2371 MWt; after the tests phase of starting-up and operation is necessary to carry out a verification of the proposed design of the vapor cycle for the new operation conditions. All this, having in consideration that the vapor cycle designer only knows the detail of the prospective performance of the main turbine, for all the other components (for example pumps, heat inter changers, valves, reactor, humidity separators and re-heaters, condensers, etc.) makes generic suppositions based on engineering judgment. This way carries out the calculations of thermal balance to determine the guaranteed gross power. The purpose of the present work is to comment the detail of the validation carried out of the specific thermal balance (thermal kit) of the nuclear power plant, making use of the design characteristics of the different components that conform the vapor cycle. (Author)

Utilization of waste heat from GT-MHR for power generation in organic Rankine cycles

International Nuclear Information System (INIS)

Yari, Mortaza; Mahmoudi, S.M.S.

2010-01-01

The gas turbine-modular helium reactor (GT-MHR) is currently being developed by an international consortium. In this power plant, circulating helium that has to be compressed in a single or two successive stages cools the reactor core. For thermodynamic reasons, these compression stages require pre-cooling of the helium to about 26 deg. C through the use of intercooler and pre-cooler in which water is used to cool the helium. Considerable thermal energy (∼300 MWth) is thus dissipated in these components. This thermal energy is then rejected to a heat sink. For different designs, the temperature ranges of the helium in the intercooler and pre-cooler could be about 100 and 150 deg. C, respectively. These are ideal energy sources to be used in an organic Rankine cycles for power generation. This study examines the performance of a gas-cooled nuclear power plant with closed Brayton cycle (CBC) combined with two organic Rankine cycles (ORC). More attention was paid to the irreversibilities generated in the combined cycle. Individual models are developed for each component through applications of the first and second laws of thermodynamics. The effects of the turbine inlet temperature, compressor pressure ratio, evaporator temperature and temperature difference in the evaporator on the first- and second-law efficiencies and on the exergy destruction rate of the combined cycle were studied. Finally the combined cycle was optimized thermodynamically using the EES (Engineering Equation Solver) software. Based on identical operating conditions, a comparison between the GT-MHR/ORC and a simple GT-MHR cycle is also made. It was found that both the first- and second-law efficiencies of GT-MHR/ORC cycle are about 3%-points higher than that of the simple GT-MHR cycle. Also, the exergy destruction rate for GT-MHR/ORC cycle is about 5% lower than that of the GT-MHR cycle.

Power Control of Permanent Magnet Generator Based Variable Speed Wind Turbines

DEFF Research Database (Denmark)

Deng, Fujin; Chen, Zhe

2009-01-01

When the wind power accounts for a large portion of the grid, it will be required to regulate the active power and reactive power. This paper investigates a MWlevel variable speed wind turbine with a permanent magnet synchronous generator (PMSG). The power control capabilities of two kinds...... of control schemes conducted respectively on this wind turbine under two conditions, including rapid wind speed change and grids faults, are compared. The simulation study of the wind turbine system is conducted using PSCAD/EMTDC, and the results show the different power control capabilities of the two...

Analysis of gas turbine systems for sustainable energy conversion

Energy Technology Data Exchange (ETDEWEB)

Anheden, Marie

2000-02-01

Increased energy demands and fear of global warming due to the emission of greenhouse gases call for development of new efficient power generation systems with low or no carbon dioxide (CO{sub 2}) emissions. In this thesis, two different gas turbine power generation systems, which are designed with these issues in mind, are theoretically investigated and analyzed. In the first gas turbine system, the fuel is combusted using a metal oxide as an oxidant instead of oxygen in the air. This process is known as Chemical Looping Combustion (CLC). CLC is claimed to decrease combustion exergy destruction and increase the power generation efficiency. Another advantage is the possibility to separate CO{sub 2} without a costly and energy demanding gas separation process. The system analysis presented includes computer-based simulations of CLC gas turbine systems with different metal oxides as oxygen carriers and different fuels. An exergy analysis comparing the exergy destruction of the gas turbine system with CLC and conventional combustion is also presented. The results show that it is theoretically possible to increase the power generation efficiency of a simple gas turbine system by introducing CLC. A combined gas/steam turbine cycle system with CLC is, however, estimated to reach a similar efficiency as the conventional combined cycle system. If the benefit of easy and energy-efficient CO{sub 2} separation is accounted for, a CLC combined cycle system has a potential to be favorable compared to a combined cycle system with CO{sub 2} separation. In the second investigation, a solid, CO{sub 2}-neutral biomass fuel is used in a small-scale externally fired gas turbine system for cogeneration of power and district heating. Both open and closed gas turbines with different working fluids are simulated and analyzed regarding thermodynamic performance, equipment size, and economics. The results show that it is possible to reach high power generation efficiency and total (power

Efficiency enhancement of a gas turbine cycle using an optimized tubular recuperative heat exchanger

International Nuclear Information System (INIS)

Sayyaadi, Hoseyn; Mehrabipour, Reza

2012-01-01

A simple gas turbine cycle namely as the Kraftwerk Union AG unit including a Siemens gas turbine model V93.1 with 60 MW nominal power and 26.0% thermal efficiency utilized in the Fars power plant located is considered for the efficiency enhancement. A typical tubular vertical recuperative heat exchanger is designed in order to integrate into the cycle as an air pre-heater for thermal efficiency improvement. Thermal and geometric specifications of the recuperative heat exchanger are obtained in a multi-objective optimization process. The exergetic efficiency of the gas cycle is maximized while the payback time for the capital investment of the recuperator is minimized. Combination of these objectives and decision variables with suitable engineering and physical constraints makes a set of the MINLP optimization problem. Optimization programming is performed using the NSGA-II algorithm and Pareto optimal frontiers are obtained in three cases including the minimum, average and maximum ambient air temperatures. In each case, the final optimal solution has been selected using three decision-making approaches including the fuzzy Bellman-Zadeh, LINMAP and TOPSIS methods. It has been shown that the TOPSIS and LINMAP decision-makers when applied on the Pareto frontier which is obtained at average ambient air temperature yields best results in comparison to other cases. -- Highlights: ► A simple Brayton gas cycle is considered for the efficiency improvement by integrating of a recuperator. ► Objective functions based on thermodynamic and economic analysis are obtained. ► The payback time for the capital investment is minimized and the exergetic efficiency of the system is maximized. ► Pareto optimal frontiers at various site conditions are obtained. ► A final optimal configuration is found using various decision-making approaches.

Dynamic wind turbine models in power system simulation tool DIgSILENT

Energy Technology Data Exchange (ETDEWEB)

Hansen, A.D.; Iov, F.; Soerensen, Poul.; Cutululis, N.; Jauch, C.; Blaabjerg, F.

2007-08-15

This report presents a collection of models and control strategies developed and implemented in the power system simulation tool PowerFactory DIgSILENT for different wind turbine concepts. It is the second edition of Risoe-R-1400(EN) and it gathers and describes a whole wind turbine model database built-op and developed during several national research projects, carried out at Risoe DTU National Laboratory for Sustainable Energy and Aalborg University, in the period 2001-2007. The overall objective of these projects was to create a wind turbine model database able to support the analysis of the interaction between the mechanical structure of the wind turbine and the electrical grid during different operational modes. The report provides thus a description of the wind turbines modelling, both at a component level and at a system level. The report contains both the description of DIgSILENT built-in models for the electrical components of a grid connected wind turbine (e.g. induction generators, power converters, transformers) and the models developed by the user, in the dynamic simulation language DSL of DIgSILENT, for the non-electrical components of the wind turbine (wind model, aerodynamic model, mechanical model). The initialisation issues on the wind turbine models into the power system simulation are also presented. The main attention in the report is drawn to the modelling at the system level of the following wind turbine concepts: (1) Fixed speed active stall wind turbine concept (2) Variable speed doubly-fed induction generator wind turbine concept (3) Variable speed multi-pole permanent magnet synchronous generator wind turbine concept These wind turbine concept models can be used and even extended for the study of different aspects, e.g. the assessment of power quality, control strategies, connection of the wind turbine at different types of grid and storage systems. Different control strategies have been developed and implemented for these wind turbine

European wind turbine testing procedure developments. Task 2: Power quality

DEFF Research Database (Denmark)

Sørensen, Poul Ejnar; Friis Pedersen, Troels; Gerdes, G.

2001-01-01

The present report describes the work done in the power quality subtask of the European Wind Turbine Testing Procedure Developments project funded by the EU SMT program. The objective of the power quality subtask has been to make recommendations andprovide background for new standards...... for measurement and testing of wind turbine power quality. The focus in the work has been to support the ongoing standardisation work in IEC with a new standard IEC61400-21 for measurement and assessment of powerquality characteristics of grid connected wind turbines. The work has also been based on the power...... quality measuremnet procedure in the Measnet cooperation of European test stations for wind turbines. The first working item of the project has been toverify the state of the art of the measurement procedures by analyses and comparisons of the measurements and data processing software of the participating...

Annual energy and environment analysis of solarized steam injection gas turbine (STIG) cycle for Indian regions

International Nuclear Information System (INIS)

Selwynraj, A. Immanuel; Iniyan, S.; Suganthi, L.; Livshits, Maya; Polonsky, Guy; Kribus, Abraham

2016-01-01

Highlights: • Study on the influence of local climatic conditions on solar STIG cycle is presented. • The annual solar to electricity efficiency ranges between 11.2 and 17.1% and the solar fraction ranges 9.3–41.7%. • The range of annual specific CO_2 emission is 312–408 kg/MWh and incremental CO_2 avoidance is 4.2–104 kg/MWh. • The levelized tariff (LT) is 0.2–0.23 $/kWh, and the solar levelized tariff (SLT) ranges from 0.11 to 0.27 $/kWh. - Abstract: The solarized steam injection gas turbine (STIG) cycle uses both the fuel and solar heat simultaneously for power generation. The annual thermodynamic performances of the cycle for sites in India with local climatic conditions such as ambient temperature, relative humidity and availability of direct normal irradiance (DNI) to the solar concentrators under two modes of constant and variable power are presented in this paper. The results reveal that the solar to electricity efficiency of solar hybrid STIG plant with a simple parabolic trough collector (PTC) is similar to existing solar thermal technologies, and also higher solar share is obtained. The study also reveals that the annual CO_2 emission is similar to combined cycle plants and lower than gas turbine technologies. The incremental CO_2 avoidance is also computed due to solar participation. The annual values of exergetic solar fraction and exergetic efficiency at Indore are higher than Jaipur. Results of an improved economic assessment show that the levelized tariff (LT) of solar hybrid STIG plant is 0.2–0.23 $/kWh and the levelized tariff (solar only) or solar levelized tariff (SLT) of solar STIG plant ranges from 0.11 to 0.27 $/kWh for both constant and variable power scenarios.

Feasibility study on rehabilitation of MEPE gas turbine power plant

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Myanmar generates majority of the whole electric power by using thermal power plants consisting of single gas turbines, and gas and steam composite turbines. However, because of chronic power shortage and fund unavailability, the major gas turbines are being operated in quite inadequate environment. As a result, reduction in power generation efficiency has become manifest due to aged deterioration, increasing the quantity of CO2 emission. The present project is, in order to link it to the 'Clean Development Mechanism' being carried out with developing countries, and placing Tharkayta Power Plant as the object, intended to comprehensively discuss a rehabilitation program to renew the existing gas turbines with advanced ones, in relation with feasibility of the project implementation including the effect of CO2 emission reduction, profitability, and proliferation effects. A prospect was acquired that, by replacing the gas turbines alone with 25-MW class gas turbines, the plant output will increase to 97.2 MW (78.5 MW in the existing facilities) and the plant efficiency to 43.3% (36.5% in the existing facilities). The energy saving effect during a period of 40 years would be 708,000 (toe) as heat consumption converted to crude oil, and the CO2 emission reducing effect would be 2,160,000 (t-CO2), respectively. (NEDO)

Power electronics converters for wind turbine systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Liserre, Marco; Ma, Ke

2011-01-01

The steady growth of installed wind power which reached 200 GW capacity in 2010, together with the up-scaling of the single wind turbine power capability - 7 MW’s has been announced by manufacturers - has pushed the research and development of power converters towards full scale power conversion,...

Closed-cycle gas turbine power generating system

International Nuclear Information System (INIS)

Jubb, A.; Ward, R.G.; Hurst, J.N.; Holliday, J.B.; Ashley, J.W.

1975-01-01

The invention deals with a gas-cooled reactor with at least one condenser, one turbin and one off-gas heat exchanger for preheating the coolant arranged in the pressure vessel inside a common supporting structure in the from of a pipe cylinder. This supporting structure can be removed from the pressure vessel independently of the core. The pipe cylinder is connected with the core feeding and recirculation lines. It has axial coolant channels in the cylindrical wall. The heat exchanger consists of a large number of coolant channels in axial direction. The feeding line is surrounded by several interpenetrating elastic ring elements. (HP) [de

Thermodynamic assessment of impact of inlet air cooling techniques on gas turbine and combined cycle performance

International Nuclear Information System (INIS)

Mohapatra, Alok Ku; Sanjay

2014-01-01

The article is focused on the comparison of impact of two different methods of inlet air cooling (vapor compression and vapor absorption cooling) integrated to a cooled gas turbine based combined cycle plant. Air-film cooling has been adopted as the cooling technique for gas turbine blades. A parametric study of the effect of compressor pressure ratio, compressor inlet temperature (T i , C ), turbine inlet temperature (T i , T ), ambient relative humidity and ambient temperature on performance parameters of plant has been carried out. Optimum T i , T corresponding to maximum plant efficiency of combined cycle increases by 100 °C due to the integration of inlet air cooling. It has been observed that vapor compression cooling improves the efficiency of gas turbine cycle by 4.88% and work output by 14.77%. In case of vapor absorption cooling an improvement of 17.2% in gas cycle work output and 9.47% in gas cycle efficiency has been observed. For combined cycle configuration, however, vapor compression cooling should be preferred over absorption cooling in terms of higher plant performance. The optimum value of compressor inlet temperature has been observed to be 20 °C for the chosen set of conditions for both the inlet air cooling schemes. - Highlights: • Inlet air cooling improves performance of cooled gas turbine based combined cycle. • Vapor compression inlet air cooling is superior to vapor absorption inlet cooling. • For every turbine inlet temperature, there exists an optimum pressure ratio. • The optimum compressor inlet temperature is found to be 293 K

Standards for measurements and testing of wind turbine power quality

Energy Technology Data Exchange (ETDEWEB)

Soerensen, P [Risoe National Lab., Roskilde (Denmark); Gerdes, G; Klosse, R; Santjer, F [DEWI, Wilhelmshaven (Germany); Robertson, N; Davy, W [NEL, Glasgow (United Kingdom); Koulouvari, M; Morfiadakis, E [CRES, Pikermi (Greece); Larsson, Aa [Chalmers Univ. of Technology, Goeteborg (Sweden)

1999-03-01

The present paper describes the work done in power quality sub-task of the project `European Wind Turbine Testing Procedure Developments` funded by the EU SMT program. The objective of the power quality sub-task has been to make analyses and new recommendation(s) for the standardisation of measurement and verification of wind turbine power quality. The work has been organised in three major activities. The first activity has been to propose measurement procedures and to verify existing and new measurement procedures. This activity has also involved a comparison of the measurements and data processing of the participating partners. The second activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with constant rotor speed. The third activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with variable rotor speed. (au)

Novel screening techniques for wind turbine power converters

DEFF Research Database (Denmark)

Jørgensen, Asger Bjørn; Sønderskov, Simon Dyhr; Christensen, Nicklas

2016-01-01

Power converters represent one of the highest failure rates in the wind turbine. Therefore converter manufacturers perform burn-in tests to prevent shipping of faulty converters. Recent developments in junction temperature estimation, based on accurate online IGBT collector-emitter voltage...... measurements, allow for thermal stress estimation of the IGBT modules. This is utilized to detect infant mortalities in power converters, by comparing thermal responses of IGBTs for faulty and non-faulty converters. The method proves to be a time and cost efficient candidate to replace burn-in tests of power...... converters for wind turbines applications....

Wind Turbine and Power Production, the Danish Development

Energy Technology Data Exchange (ETDEWEB)

Kjems, Joergen; Oester, Flemming

2007-07-01

The progress within the Danish wind energy sector in Denmark is reviewed. Excluding minor intermission periods the R and D development of electricity producing wind turbines has taken place continuously for more than 100 years in Denmark. After the first oil crisis in 1973 this development accelerated and has led to a remarkable scientific and commercial success. For a few years turbines in Denmark have been producing electricity corresponding to almost 20% of the Danish demand. Danish manufacturers produce components and export turbines in large quantities, amounting in 2005 to a total capacity of about 3.8 GW which is about one third of the world market. Important present day R&D topics are offshore technology and interaction between turbines and the grid, including the ability of turbines to contribute to regulation and stabilization of the power system. These questions are crucial when handling fluctuating electricity production in networks with large fractions of wind energy and CHP power production. In the future, a main point may be storage of wind energy, e.g. in the form of hydrogen produced by fuel cells. (auth)

A comparison of advanced thermal cycles suitable for upgrading existing power plant

International Nuclear Information System (INIS)

Heyen, G.; Kalitventzeff, B.

1999-01-01

In view of the constant growth of electricity usage and public pressure to reduce the dependence on nuclear power plants in the energy supply, solutions are sought to increase the capacity of power plants using fossil fuels. Highly efficient cycles are available: gas turbines combined with waste heat boilers and steam cycles are able to achieve efficiencies above 50-55%. However building new plants requires a large amount of capital.Alternative proposals are based on upgrades of existing plants : capital savings are expected by reusing part of the facilities. In the present study, three parallel proposals are compared on the basis of exergy efficiency; cost of investment and flexibility of operation are also discussed. They are compared with classical Rankine cycle and state of the art combined cycles. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Reliability Assessment of Solder Joints in Power Electronic Modules by Crack Damage Model for Wind Turbine Applications

DEFF Research Database (Denmark)

Kostandyan, Erik; Sørensen, John Dalsgaard

2011-01-01

Wind turbine reliability is an important issue for wind energy cost minimization, especially by reduction of operation and maintenance costs for critical components and by increasing wind turbine availability. To develop an optimal operation and maintenance plan for critical components, it is nec......Wind turbine reliability is an important issue for wind energy cost minimization, especially by reduction of operation and maintenance costs for critical components and by increasing wind turbine availability. To develop an optimal operation and maintenance plan for critical components...... to each other and they operate at a thermal-power cycling environment. Temperature loadings affect the reliability of soldered joints by developing cracks and fatigue processes that eventually result in failure. Based on Miner’s rule a linear damage model that incorporates a crack development...

Part-Load Performance of aWet Indirectly Fired Gas Turbine Integrated with an Organic Rankine Cycle Turbogenerator

Directory of Open Access Journals (Sweden)

Leonardo Pierobon

2014-12-01

Full Text Available Over the last years, much attention has been paid to the development of efficient and low-cost power systems for biomass-to-electricity conversion. This paper aims at investigating the design- and part-load performance of an innovative plant based on a wet indirectly fired gas turbine (WIFGT fueled by woodchips and an organic Rankine cycle (ORC turbogenerator. An exergy analysis is performed to identify the sources of inefficiencies, the optimal design variables, and the most suitable working fluid for the organic Rankine process. This step enables to parametrize the part-load model of the plant and to estimate its performance at different power outputs. The novel plant has a nominal power of 250 kW and a thermal efficiency of 43%. The major irreversibilities take place in the burner, recuperator, compressor and in the condenser. Toluene is the optimal working fluid for the organic Rankine engine. The part-load investigation indicates that the plant can operate at high efficiencies over a wide range of power outputs (50%–100%, with a peak thermal efficiency of 45% at around 80% load. While the ORC turbogenerator is responsible for the efficiency drop at low capacities, the off-design performance is governed by the efficiency characteristics of the compressor and turbine serving the gas turbine unit.

New pressure control method of mixed gas in a combined cycle power plant of a steel mill

Science.gov (United States)

Xie, Yudong; Wang, Yong

2017-08-01

The enterprise production concept is changing with the development of society. A steel mill requires a combined-cycle power plant, which consists of both a gas turbine and steam turbine. It can recycle energy from the gases that are emitted from coke ovens and blast furnaces during steel production. This plant can decrease the overall energy consumption of the steel mill and reduce pollution to our living environment. To develop a combined-cycle power plant, the pressure in the mixed-gas transmission system must be controlled in the range of 2.30-2.40 MPa. The particularity of the combined-cycle power plant poses a challenge to conventional controllers. In this paper, a composite control method based on the Smith predictor and cascade control was proposed for the pressure control of the mixed gases. This method has a concise structure and can be easily implemented in actual industrial fields. The experiment has been conducted to validate the proposed control method. The experiment illustrates that the proposed method can suppress various disturbances in the gas transmission control system and sustain the pressure of the gas at the desired level, which helps to avoid abnormal shutdowns in the combined-cycle power plant.

Development of low head Kaplan turbine for power station rehabilitation project

Science.gov (United States)

Lim, S. M.; Ohtake, N.; Kurosawa, S.; Suzuki, T.; Yamasaki, T.; Nishi, H.

2012-11-01

This paper presents the latest Kaplan turbine rehabilitation project for Funagira Power Station in Japan completed by J-POWER Group in collaboration with Toshiba Corporation. Area of rehabilitation was restricted to guide vane and runner. The main goal of the rehabilitation project was to expand the operating range of the existing turbine in terms of discharge and power with high operational stability, low noise as well as high cavitation performance. Computational Fluids Dynamics and model test were used to optimize the shape of guide vane and runner in development stage. Finally, field tests and runner inspection were carried out to confirm the performance of the new turbine. It was found that the new turbine has excellent performance in efficiency, power output, operational stability compared with existing turbine. Moreover, no sign of cavitation on the runner blade surface was observed after 5078 hours of operation near 100% load.

Development of low head Kaplan turbine for power station rehabilitation project

International Nuclear Information System (INIS)

Lim, S M; Ohtake, N; Kurosawa, S; Suzuki, T; Yamasaki, T; Nishi, H

2012-01-01

This paper presents the latest Kaplan turbine rehabilitation project for Funagira Power Station in Japan completed by J-POWER Group in collaboration with Toshiba Corporation. Area of rehabilitation was restricted to guide vane and runner. The main goal of the rehabilitation project was to expand the operating range of the existing turbine in terms of discharge and power with high operational stability, low noise as well as high cavitation performance. Computational Fluids Dynamics and model test were used to optimize the shape of guide vane and runner in development stage. Finally, field tests and runner inspection were carried out to confirm the performance of the new turbine. It was found that the new turbine has excellent performance in efficiency, power output, operational stability compared with existing turbine. Moreover, no sign of cavitation on the runner blade surface was observed after 5078 hours of operation near 100% load.

Compensation of Reactive Power from Wind Turbines with Power Electronics Equipment

DEFF Research Database (Denmark)

Pedersen, Jørgen Kaas

1996-01-01

Wind turbines with induction generators consume reactive power. Apart from the no load consumption, which is nearing constant and is being compensated for using capacitors, the consumption of reactive power varies almost proportional with the power production, which can vary immensely. Except tha...

Study on gas turbines. Leading role of high efficiency power generation; Gas turbine kenkyu. Kokoritsu hatsuden no shuyaku wo nerau

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-31

This review summarizes research works of Central Research Institute of Electric Power Industry on gas turbines playing a leading role of high efficiency power generation. This article describes historical changes of gas turbine technology, changes and current status from the viewpoint of electric power industry, and development trend in various makers. Increase in the flow-in gas temperature, low NOx combustion technology, use of various fuels, and durability evaluation and improvement technology for high temperature parts are described as technological problems and development trends. The increase in temperature is indispensable for the improvement of efficiency. Materials having heat resistance, anticorrosion and strength are required. Accordingly, Ni-based single crystal super alloy has been developed. Developments of ceramic gas turbine and catalytic combustor are also described. The coal gasification combined power generation is expected as a new power generation technology having availability of various coals, high efficiency, and excellent environmental protection. Development of 1500 {degree}C class combustor for turbines has been promoted. Evaluation and improvement of durability of high temperature parts are also described. For the new utilization technology of gas turbines, repowering and compressed air storage gas turbine power generation technology are introduced. 92 figs., 14 tabs.

Dynamic wind turbine models in power system simulation tool DIgSILENT

Energy Technology Data Exchange (ETDEWEB)

Hansen, A.C.; Jauch, C.; Soerensen, P.; Iov, F.; Blaabjerg, F.

2003-12-01

The present report describes the dynamic wind turbine models implemented in the power system simulation tool DIgSILENT (Version 12.0). The developed models are a part of the results of a national research project, whose overall objective is to create a model database in different simulation tools. This model database should be able to support the analysis of the interaction between the mechanical structure of the wind turbine and the electrical grid during different operational modes. The report provides a description of the wind turbines modelling, both at a component level and at a system level. The report contains both the description of DIgSILENT built-in models for the electrical components of a grid connected wind turbine (e.g. induction generators, power converters, transformers) and the models developed by the user, in the dynamic simulation language DSL of DIgSILENT, for the non-electrical components of the wind turbine (wind model, aerodynamic model, mechanical model). The initialisation issues on the wind turbine models into the power system simulation are also presented. However, the main attention in this report is drawn to the modelling at the system level of two wind turbine concepts: 1. Active stall wind turbine with induction generator 2. Variable speed, variable pitch wind turbine with doubly fed induction generator. These wind turbine concept models can be used and even extended for the study of different aspects, e.g. the assessment of power quality, control strategies, connection of the wind turbine at different types of grid and storage systems. For both these two concepts, control strategies are developed and implemented, their performance assessed and discussed by means of simulations. (au)

Numerical optimization of Combined Heat and Power Organic Rankine Cycles – Part A: Design optimization

International Nuclear Information System (INIS)

Martelli, Emanuele; Capra, Federico; Consonni, Stefano

2015-01-01

This two-part paper proposes an approach based on state-of-the-art numerical optimization methods for simultaneously determining the most profitable design and part-load operation of Combined Heat and Power Organic Rankine Cycles. Compared to the usual design practice, the important advantages of the proposed approach are (i) to consider the part-load performance of the ORC at the design stage, (ii) to optimize not only the cycle variables, but also the main turbine design variables (number of stages, stage loads, rotational speed). In this first part (Part A), the design model and the optimization algorithm are presented and tested on a real-world test case. PGS-COM, a recently proposed hybrid derivative-free algorithm, allows to efficiently tackle the challenging non-smooth black-box problem. - Highlights: • Algorithm for the simultaneous optimization Organic Rakine Cycle and turbine. • Thermodynamic and economic models of boiler, cycle, turbine are developed. • Non-smooth black-box optimization problem is successfully tackled with PGS-COM. • Test cases show that the algorithm returns optimal solutions within 4 min. • Toluene outperforms MDM (a siloxane) in terms of efficiency and costs.

Floating axis wind turbines for offshore power generation—a conceptual study

International Nuclear Information System (INIS)

Akimoto, Hiromichi; Tanaka, Kenji; Uzawa, Kiyoshi

2011-01-01

The cost of energy produced by offshore wind turbines is considered to be higher than land based ones because of the difficulties in construction, operation and maintenance on offshore sites. To solve the problem, we propose a concept of a wind turbine that is specially designed for an offshore environment. In the proposed concept, a floater of revolutionary shape supports the load of the wind turbine axis. The floater rotates with the turbine and the turbine axis tilts to balance the turbine thrust, buoyancy and gravity. The tilt angle is passively adjustable to wind force. The angle is 30° at rated power. The simplicity of the system leads to further cost reduction of offshore power generation.

Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture

International Nuclear Information System (INIS)

Rieger, Mathias

2014-01-01

The objective of this thesis is to provide an extensive description of the correlations in some of the most crucial sub-processes for hard coal fired IGCC with carbon capture (CC-IGCC). For this purpose, process simulation models are developed for four industrial gasification processes, the CO-shift cycle, the acid gas removal unit, the sulfur recovery process, the gas turbine, the water-/steam cycle and the air separation unit (ASU). Process simulations clarify the influence of certain boundary conditions on plant operation, performance and economics. Based on that, a comparative benchmark of CC-IGCC concepts is conducted. Furthermore, the influence of integration between the gas turbine and the ASU is analyzed in detail. The generated findings are used to develop an advanced plant configuration with improved economics. Nevertheless, IGCC power plants with carbon capture are not found to be an economically efficient power generation technology at present day boundary conditions.