Optimization of Regenerated Gas Turbines

1996 ◽  
Vol 118 (3) ◽  
pp. 654-660 ◽  
Author(s):  
D. S. Beck
Keyword(s):  
Optimization Algorithm ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Automotive Applications

An algorithm for the optimization of regenerated gas turbines is given. For sets of inputs that are typical for automotive applications, the optimum cycle pressure ratio and a set of optimized regenerator parameters that maximize thermal efficiency are given. A second algorithm, an algorithm for sizing regenerators based on outputs of the optimization algorithm, is given. With this sizing algorithm, unique regenerator designs can be determined for many applications based on the presented optimization data. Results of example sizings are given. The data indicate that one core (instead of two cores) should be used to maximize thermal efficiency. The data also indicate that thermal efficiencies of over 50 percent should be achievable for automotive applications if ceramic turbines are used.

scholarly journals Optimization of Regenerated Gas Turbines

1994 ◽  
Author(s):  
Douglas Stephen Beck
Keyword(s):  
Optimization Algorithm ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Automotive Applications

An algorithm for the optimization of regenerated gas turbines is given. For sets of inputs that are typical for automotive applications, the optimum cycle pressure ratio and a set of optimized regenerator parameters that maximize thermal efficiency are given. A second algorithm, an algorithm for sizing regenerators based on outputs of the optimization algorithm, is given. With this sizing algorithm, unique regenerator designs can be determined for many applications based on the presented optimization data. Results of example sizings are given. The data indicate that one core (instead of two cores) should be used to maximize thermal efficiency. The data also indicate that thermal efficiencies of over 50% should be achievable for automotive applications if ceramic turbines are used.

Application of “H Gas Turbine” Design Technology to Increase Thermal Efficiency and Output Capability of the Mitsubishi M701G2 Gas Turbine

2005 ◽  
Vol 127 (2) ◽  
pp. 369-374 ◽  
Author(s):  
Y. Fukuizumi ◽  
J. Masada ◽  
V. Kallianpur ◽  
Y. Iwasaki
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Turbine Blades ◽  
Combined Cycle ◽  
Load Test ◽  
Air Cooling ◽  
Load Testing ◽  
Design Development

Mitsubishi completed design development and verification load testing of a steam-cooled M501H gas turbine at a combined cycle power plant at Takasago, Japan in 2001. Several advanced technologies were specifically developed in addition to the steam-cooled components consisting of the combustor, turbine blades, vanes, and the rotor. Some of the other key technologies consisted of an advanced compressor with a pressure ratio of 25:1, active clearance control, and advanced seal technology. Prior to the M501H, Mitsubishi introduced cooling-steam in “G series” gas turbines in 1997 to cool combustor liners. Recently, some of the advanced design technologies from the M501H gas turbine were applied to the G series gas turbine resulting in significant improvement in output and thermal efficiency. A noteworthy aspect of the technology transfer is that the upgraded G series M701G2 gas turbine has an almost equivalent output and thermal efficiency as H class gas turbines while continuing to rely on conventional air cooling of turbine blades and vanes, and time-proven materials from industrial gas turbine experience. In this paper we describe the key design features of the M701G2 gas turbine that make this possible such as the advanced 21:1 compressor with 14 stages, an advanced premix DLN combustor, etc., as well as shop load test results that were completed in 2002 at Mitsubishi’s in-house facility.

Full Coverage Film-Cooled Blading in High Temperature Gas Turbines: Cooling Effectiveness, Profile Loss and Thermal Efficiency

1980 ◽  
Vol 102 (4) ◽  
pp. 957-963 ◽  
Author(s):  
H. Hempel ◽  
R. Friedrich ◽  
S. Wittig
Keyword(s):  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Specific Work ◽  
Cooling Effectiveness ◽  
Common Component ◽  
Full Coverage ◽  
Cooling Air Flow ◽  
Cooling Air ◽  
Profile Loss

Extending data obtained from hot gas cascade measurements on the cooling effectiveness and profile loss coefficients of full coverage film-cooled blading, use is made of similarity considerations to determine the heat transfer characteristics under actual engine conditions. Of primary interest are stationary gas turbines. Calculations are made for a four-stage single shaft gas turbine with air preheat and common component efficiencies. As a representative result it is found that for a pressure ratio of π = 10 a relative cooling air flow of approximately 8 percent will be required in rising the temperature from 1173 to 1573 K. The resulting relative improvement of the thermal efficiency is 24 percent and that of the specific work about 70 percent.

Genetic Optimization of Steam Injected Gas Turbine Power Plants

2002 ◽  
Author(s):  
Ibrahim Sinan Akmandor ◽  
O¨zhan O¨ksu¨z ◽  
Sec¸kin Go¨kaltun ◽  
Melih Han Bilgin
Keyword(s):  
Gas Turbine ◽  
Power Output ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Power Plants ◽  
Pressure Ratio ◽  
Steam Injection ◽  
Combined Cycle ◽  
Inlet Temperature ◽  
Compressor Pressure Ratio

A new methodology is developed to find the optimal steam injection levels in simple and combined cycle gas turbine power plants. When steam injection process is being applied to simple cycle gas turbines, it is shown to offer many benefits, including increased power output and efficiency as well as reduced exhaust emissions. For combined cycle power plants, steam injection in the gas turbine, significantly decreases the amount of flow and energy through the steam turbine and the overall power output of the combined cycle is decreased. This study focuses on finding the maximum power output and efficiency of steam injected simple and combined cycle gas turbines. For that purpose, the thermodynamic cycle analysis and a genetic algorithm are linked within an automated design loop. The multi-parameter objective function is either based on the power output or on the overall thermal efficiency. NOx levels have also been taken into account in a third objective function denoted as steam injection effectiveness. The calculations are done for a wide range of parameters such as compressor pressure ratio, turbine inlet temperature, air and steam mass flow rates. Firstly, 6 widely used simple and combined cycle power plants performance are used as test cases for thermodynamic cycle validation. Secondly, gas turbine main parameters are modified to yield the maximum generator power and thermal efficiency. Finally, the effects of uniform crossover, creep mutation, different random number seeds, population size and the number of children per pair of parents on the performance of the genetic algorithm are studied. Parametric analyses show that application of high turbine inlet temperature, high air mass flow rate and no steam injection lead to high power and high combined cycle thermal efficiency. On the contrary, when NOx reduction is desired, steam injection is necessary. For simple cycle, almost full amount of steam injection is required to increase power and efficiency as well as to reduce NOx. Moreover, it is found that the compressor pressure ratio for high power output is significantly lower than the compressor pressure ratio that drives the high thermal efficiency.

scholarly journals Design optimization of industrial gas turbines using simulated annealing algorithms

2018 ◽  
Vol 225 ◽  
pp. 02018
Author(s):  
Mohammadreza Tahan ◽  
A.L. Tamiru ◽  
Masdi Muhammad
Keyword(s):  
Simulated Annealing ◽  
Design Optimization ◽  
Gas Turbine ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Simulated Annealing Algorithm ◽  
Pressure Ratio ◽  
Optimal Solution ◽  
Evolutionary Model ◽  
Compression Pressure

Currently, gas turbine is one of the most widely-used power generating technologies. The race to achieve higher efficiency from gas turbines is gathering momentum with most of the major manufacturers. Cogeneration with advanced engines has the prospect of attaining thermal efficiencies around 60% in the future. In this condition, further development of gas turbine design optimization in order to obtain higher thermal efficiency seems to be beneficial. In the current work, the design of a single shaft gas turbine in a cogeneration plant is optimized based on the model established using thermodynamic theory. The overall thermal efficiency of the engine is tried to be optimized by adjusting the compressor efficiency, turbine efficiency, compression pressure ratio, and turbine inlet temperatures. A feasible solution should satisfy two physical constraints, namely a desired gas turbine power and a suitable limit of engine exhaust temperature. An evolutionary model using Simulated Annealing algorithm is developed to find the sets of optimal solutions in the space defined by user experience and literature. A number of case studies have been performed and an optimal solution and their corresponding performance are discussed.

Thermo-Economics of a Small 50 KW Turbogenerator

1997 ◽  
Author(s):  
C. Rodgers
Keyword(s):  
Thermal Efficiency ◽  
Gas Turbines ◽  
High Speed ◽  
Pressure Ratio ◽  
Operating Time ◽  
Cycle Performance ◽  
Material Technology ◽  
Diesel Cycle ◽  
Near Term

Recent projections foster the belief that small high temperature heat exchanged gas turbines incorporating ceramic rotors, and ceramic exhaust beat exchangers, may eventually have thermodynamic efficiencies competitive with Diesel cycle engines. Small high speed Brayton cycle gas turbine turbogenerators on the near term verge of production will indeed have improved thermal efficiencies, but ceramic material technology has not yet matured to the engine production stage. Although thermal efficiency is a dominant driver, manufacturing costs and long term engine durability are still a major concern to the engine manufacturer. As a consequence the thermodynamic performances of small gas turbines are still, in this last decade of the 20th century, primarily constrained by the temperature limits of the metallic stator/rotor and metallic heat exchanger. This paper reviews optimum thermo-economic design considerations for a small 50 KW output turbogenerator, covering the effect of cycle performance parameters on, engine configuration, rotational speeds engine weight, manufacturing and direct operating costs. The effect of design pressure ratio on part load thermal efficiency is also addressed for applications with extended operating time at low output powers.

Modified Brayton Cycles Utilizing Alcohol Fuels

1982 ◽  
Vol 104 (2) ◽  
pp. 341-348 ◽  
Author(s):  
M. F. Bardon
Keyword(s):  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Inlet Temperature ◽  
Specific Work ◽  
Brayton Cycle ◽  
Compression Process ◽  
Turbine Inlet Temperature ◽  
Optimum Pressure ◽  
Alcohol Fuels

It is already well known that alcohols can be burned in open-cycle gas turbines by direct firing in the combustor. This paper demonstrates however, that there are significant improvements in thermal efficiency possible by modifying the manner in which alcohols are used in Brayton cycle engines. It is shown that injection of the alcohol during the compression process can materially improve both thermal efficiency and specific work because of the intercooling effect of evaporation. Calculations are given which demonstrate the improvement theoretically possible at representative values of peak turbine inlet temperature. It is also shown that the optimum pressure ratio for both regenerated and unregenerated cycles is different when such compressor evaporative intercooling is used rather than simply injecting the fuel into the combustor.

Gas Dynamic Simulation of Shockless Explosion Combustion for Gas Turbine Power Cycles

2017 ◽  
Author(s):  
T. S. Rähse ◽  
C. O. Paschereit ◽  
P. Stathopoulos ◽  
P. Berndt ◽  
R. Klein
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Inlet Temperature ◽  
Power Cycles ◽  
Total Enthalpy ◽  
Gas Dynamic ◽  
Turbine Inlet ◽  
Homogeneous Combustion

With the ongoing stagnation of the progress towards higher efficiency gas turbines, alternative approaches in combustion receive more attention than ever before. Besides, increasing efficiency and reducing emissions at the same time has become a first priority of the industry in the last few decades. Constant volume combustion is considered a technology capable of achieving a significant increase in thermal efficiency when applied in gas turbines. In this work, models of gas turbine cycles with two different combustion methods, being a shockless explosion combustion and an isobaric homogeneous combustion, will be simulated and compared. A code based on the one dimensional Euler equations is utilized to calculate the exhaust gas outlet parameters of the shockless explosion combustion chamber, while taking into account all the gas dynamic phenomena in it. The efficiency of the turbine is computed by steady state operational maps. The simulations provide numerous detailed results with a focus on the dependency of the SEC cycle’s thermal efficiency to the compressor pressure ratio and the turbine inlet temperature. Evaluating the kinetic energy in the total enthalpy of the turbine inlet flow is also an essential investigation.

scholarly journals Thermal calculations and NOx emission analysis of a micro gas turbine system without a recuperator

2021 ◽  
pp. 336-336
Author(s):  
Yunyun Wang ◽  
Jiang Liu ◽  
Luyu Wang ◽  
Fu Zaiguo ◽  
Peifen Weng
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Nox Emission ◽  
Design Parameters ◽  
Thermal Calculation ◽  
Performance Parameters ◽  
Micro Gas Turbine ◽  
Thermal Calculations

A thermal calculation based on a table of thermal properties of gas was carried out for a micro gas turbine system without a recuperator. The performance parameters of the micro gas turbine system were obtained. The results of the thermal calculations were verified using Aspen Plus, and it shows that the thermal calculations fit well with the Aspen simulation results. Based on this thermal calculation method, the variation of the performance parameters of the micro gas turbine system under different pressure and temperature ratios was analyzed. The results show that there is no optimum pressure ratio within the general design parameters of micro gas turbines, which leads to extreme values of thermal efficiency. The NOx generation in the combustion chamber of the micro gas turbine based on the Zeldovich mechanism was modeled and analyzed by coupling the one-dimensional thermal calculation model with the NOx emission model. The relationship between NOx generation rate, molar fuel factor, the characteristic pressure, and the characteristic temperature was obtained. The results of the analysis show that, in terms of controlling NOx emissions from a gas turbine, the use of an increased pressure ratio has a significant advantage over an increased temperature ratio to improve the thermal efficiency of the micro gas turbine.

scholarly journals A Case Study of Mixed Gas-Steam Cycle GT: LM6000 Class Aeroderivative Gas Turbine

1999 ◽  
Author(s):  
Kirk Hanawa
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Methanol Conversion ◽  
Combined Cycle ◽  
Mixed Gas ◽  
Kalina Cycle ◽  
Water Steam ◽  
Steam Cycle

Many ideas were proposed to aim the generation thermal efficiency up to 60%, such as “Steam-Cooled H-Tech. Combined Cycle”, “Methanol Conversion Regenerative Gas Turbine”, “Kalina Cycle” etc. The target thermal efficiency of 60% based upon LHV, could be also attained, when applying mixed gas-steam cycle like ISTIG and/or GAS3D for advanced aeroderivative gas turbines, which comprise of multiple shafts with overall pressure ratio more than 50, and TIT more than 2600 F (1700 K). It might be meaningful to evaluate existing aeroderivative gas turbines like LM6000 etc. by applying such a improving concept, as the more advanced gas turbines to be derived from GE90, PW4000, and Trent800 are not available to date for land applications. The intercooled ICAD GT of 77 MW was adopted as a base engine, and it was derived that the water /steam-injected WI/GAS3D GT version could produce 106 MW with 56% thermal efficiency, and it must be emphasized that the power curve in variation with ambient temperature is very flat than conventional GT plants.

Sign in / Sign up

Export Citation Format

Share Document