Evaluation of the Compression-Intercooled Reheat-Gas-Turbine-Combined Cycle

1984 ◽  
Author(s):  
Ivan G. Rice
Keyword(s):  
Gas Turbine ◽  
Thermodynamic Analysis ◽  
Pressure Range ◽  
Pressure Ratio ◽  
Combined Cycle ◽  
Time Increase ◽  
Efficiency Loss ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency ◽  
Turbine Output

Interest in the reheat-gas turbine (RHGT) as a way to improve combined-cycle efficiency is gaining momentum. Compression intercooling makes it possible to readily increase the reheat-gas-turbine cycle-pressure ratio and at the same time increase gas-turbine output; but at the expense of some combined-cycle efficiency and mechanical complexity. This paper presents a thermodynamic analysis of the intercooled cycle and pinpoints the proper intercooling pressure range for minimum combined-cycle-efficiency loss. At the end of the paper two-intercooled reheat-gas-turbine configurations are presented.

scholarly journals Thermodynamic Analysis of Different Configurations of Combined Cycle Power Plants

2015 ◽  
Vol 5 (2) ◽  
pp. 89
Author(s):  
Munzer S. Y. Ebaid ◽  
Qusai Z. Al-hamdan
Keyword(s):  
Gas Turbine ◽  
Power Plants ◽  
Combined Cycle ◽  
Cycle Performance ◽  
Maximum Efficiency ◽  
Specific Work ◽  
Slight Effect ◽  
Turbine Engine ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency

<p class="1Body">Several modifications have been made to the simple gas turbine cycle in order to increase its thermal efficiency but within the thermal and mechanical stress constrain, the efficiency still ranges between 38 and 42%. The concept of using combined cycle power or CPP plant would be more attractive in hot countries than the combined heat and power or CHP plant. The current work deals with the performance of different configurations of the gas turbine engine operating as a part of the combined cycle power plant. The results showed that the maximum CPP cycle efficiency would be at a point for which the gas turbine cycle would have neither its maximum efficiency nor its maximum specific work output. It has been shown that supplementary heating or gas turbine reheating would decrease the CPP cycle efficiency; hence, it could only be justified at low gas turbine inlet temperatures. Also it has been shown that although gas turbine intercooling would enhance the performance of the gas turbine cycle, it would have only a slight effect on the CPP cycle performance.</p>

Evolution and Future Trend of Large Frame Gas Turbines: A New 1600 Degree C, J Class Gas Turbine

2012 ◽  
Author(s):  
Satoshi Hada ◽  
Masanori Yuri ◽  
Junichiro Masada ◽  
Eisaku Ito ◽  
Keizo Tsukagoshi
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Standard Condition ◽  
Development Program ◽  
Combined Cycle ◽  
Component Technology ◽  
Extensive Experience ◽  
National Project ◽  
Cycle Efficiency

MHI recently developed a 1600°C class J-type gas turbine, utilizing some of the technologies developed in the National Project to promote the development of component technology for the next generation 1700°C class gas turbine. This new frame is expected to achieve higher combined cycle efficiency and will contribute to reduce CO2 emissions. The target combined cycle efficiency of the J type gas turbine will be above 61.5% (gross, ISO standard condition, LHV) and the 1on1 combined cycle output will reach 460MW for 60Hz engine and 670MW for 50Hz engine. This new engine incorporates: 1) A high pressure ratio compressor based on the advanced M501H compressor, which was verified during the M501H development in 1999 and 2001. 2) Steam cooled combustor, which has accumulated extensive experience in the MHI G engine (> 1,356,000 actual operating hours). 3) State-of-art turbine designs developed through the 1700°C gas turbine component technology development program in Japanese National Project for high temperature components. This paper discusses the technical features and the updated status of the J-type gas turbine, especially the operating condition of the J-type gas turbine in the MHI demonstration plant, T-Point. The trial operation of the first M501J gas turbine was started at T-point in February 2011 on schedule, and major milestones of the trial operation have been met. After the trial operation, the first commercial operation has taken place as scheduled under a predominantly Daily-Start-and-Stop (DSS) mode. Afterward, MHI performed the major inspection in October 2011 in order to check the mechanical condition, and confirmed that the hot parts and other parts were in sound condition.

The Reheat Gas Turbine With Steam-Blade Cooling—A Means of Increasing Reheat Pressure, Output, and Combined Cycle Efficiency

1982 ◽  
Vol 104 (1) ◽  
pp. 9-22 ◽  
Author(s):  
I. G. Rice
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Pressure Rise ◽  
Expansion Ratio ◽  
Combined Cycle ◽  
Gas Generator ◽  
Exhaust Temperature ◽  
Blade Cooling ◽  
Cycle Efficiency ◽  
Turbine Blading

The reheat (RH) pressure can be appreciably increased by applying steam cooling to the gas-generator (GG) turbine blading which in turn allows a higher RH firing temperature for a fixed exhaust temperature. These factors increase gas turbine output and raise combined-cycle efficiency. The GG turbine blading will approach “uncooled expansion efficiency”. Eliminating cooling air increases the gas turbine RH pressure by 10.6 percent. When steam is used (injected) as the blade coolant, additional GG work is also developed which further increases the RH pressure by another 12.0 percent to yield a total increase of approximately 22.6 percent. The 38-cycle pressure ratio 2400° F (1316° C) TIT GG studied produces a respectable 6.5 power turbine expansion ratio. The higher pressure also noticeably reduces the physical size of the RH combustor. This paper presents an analysis of the RH pressure rise when applying steam to blade cooling.

Steam-Cooled Gas Turbine Casings, Struts, and Disks in a Reheat Gas Turbine Combined Cycle: Part I—Compressor and Combustor

1983 ◽  
Vol 105 (4) ◽  
pp. 844-850 ◽  
Author(s):  
I. G. Rice
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Gas Turbines ◽  
High Performance ◽  
Material Selection ◽  
Pressure Ratio ◽  
Industrial Applications ◽  
Combined Cycle ◽  
Tip Clearance ◽  
Turbine Output

High-cycle pressure-ratio (38–42) gas turbines being developed for future aircraft and, in turn, industrial applications impose more critical disk and casing cooling and thermal-expansion problems. Additional attention, therefore, is being focused on cooling and the proper selection of materials. Associated blade-tip clearance control of the high-pressure compressor and high-temperature turbine is critical for high performance. This paper relates to the use of extracted steam from a steam turbine as a coolant in a combined cycle to enhance material selection and to control expansion in such a manner that the cooling process increases combined-cycle efficiency, gas turbine output, and steam turbine output.

Effect of Bottoming Cycle Alternatives on the Performance of Combined Cycle

2003 ◽  
Author(s):  
R. Yadav
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Positive Influence ◽  
Combined Cycle ◽  
Exhaust Temperature ◽  
Compressor Pressure Ratio ◽  
Topping Cycle ◽  
Steam Parameters ◽  
Cycle Efficiency ◽  
Steam Cycle

The increase in efficiency of combined cycle has mainly been caused by the improvements in gas turbine cycle efficiency. With the increase in firing temperature the exhaust temperature is substantially high around 873 K for moderate compressor pressure ratio, which has positive influence on steam cycle efficiency. Minimizing the irreversibility within the heat recovery steam generator HRSG and choosing proper steam cycle configuration with optimized steam parameters improve the steam cycle efficiency and thus in turn the combined cycle efficiency. In this paper, LM9001H gas turbine, a state of art technology turbine with modified compressor pressure ratio has been chosen as a topping cycle. Various bottoming cycles alternatives (sub-critical) coupled with LM9001H topping cycle with and without recuperation such as dual and triple pressure steam cycles with and without reheat have been chosen to predict the performance of combined cycle.

Simulations of Pressurized Fluidized Circulating Bed Based Combined Cycle (PFCB)

2014 ◽  
Author(s):  
Hossin Omar ◽  
Mohamed Elmnefi
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Compression Ratio ◽  
Steam Pressure ◽  
Combined Cycle ◽  
Flue Gases ◽  
First Case ◽  
Combined Cycle Plant ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency

The Pressurized Fluidized Circulating Bed (PFCB) combined cycle was simulated. The simulations balance the energy between the elements of the unit, which consists of gas turbine cycle and steam turbine cycle. The PFCB is used as a combustor and steam generator at the same time. The simulations were carried out for PFCB combined cycle plant for two cases. In the first case, the simulations were performed for combined cycle with reheat in the steam turbine cycle. While in the second case, the simulations were carried out for the PFCB combined cycle with extra combustor and steam turbine cycle with reheat. For both cases, the effect of steam inlet pressure on the combined cycle efficiency was predicted. It was found that increasing of steam pressure results in increase in the combined cycle thermal efficiency. The effect of the inlet flue gases temperature on the gas turbine and on the combined cycle efficiencies was also predicted. The maximum PFCB combined cycle efficiency occurs at a compression ratio of 18, which is the case of utilizing an extra combustor. The simulations were carried out for only one fuel composition and for a compression ratio ranges between 1 to 40.

The Optimum Pressure Ratio for a Combined Cycle Gas Turbine Plant

1995 ◽  
Vol 209 (4) ◽  
pp. 259-264 ◽  
Author(s):  
J H Horlock
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Combined Cycle ◽  
Maximum Efficiency ◽  
Specific Work ◽  
Optimum Pressure ◽  
Turbine Plant ◽  
Gas Turbine Plant ◽  
Overall Efficiency ◽  
Gas Turbine Cycle

A graphical method of calculating the performance of gas turbine cycles, developed by Hawthorne and Davis (1), is adapted to determine the pressure ratio of a combined cycle gas turbine (CCGT) plant which will give maximum overall efficiency. The results of this approximate analysis show that the optimum pressure ratio is less than that for maximum efficiency in the higher level (gas turbine) cycle but greater than that for maximum specific work in that cycle. Introduction of reheat into the higher cycle increases the pressure ratio required for maximum overall efficiency.

Optimization of MHD Generator Based Combined Cycle Efficiency

2005 ◽  
Author(s):  
M. H. Saidi ◽  
A. A. Mozafari ◽  
H. D. Rezaei ◽  
A. J. Dehkordy
Keyword(s):  
Pressure Ratio ◽  
Combined Cycle ◽  
Second Law ◽  
Exergy Destruction ◽  
Mhd Generator ◽  
Pros And Cons ◽  
Combined Cycles ◽  
Power Generation Systems ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency

Energy crisis has directed scientific efforts to increase the efficiency of power generation systems. Thermodynamic optimization of MHD (Magneto Hydrodynamic) generator based combined cycles due to their high operating temperatures may seriously reduce exergy, destruction and improve the second law efficiency. In this research a combined cycle, comprising of MHD cycle as topping and gas turbine cycle as bottoming cycle has been simulated and analyzed and its pros and cons have been exposed. The first and second law efficiencies have been estimated from the operating pressures and temperatures of the system. To calculate the second law efficiency, the entropy generation of all components of the combined cycle has been parametrically calculated. Furthermore, the optimal pressure ratio and working temperature for both cycles are represented. The influence of pressure loss in pipeline and the effect of heat exchanger performance on the cycle efficiency have been considered as well.

Review of a Combined Steam and Gas Turbine Cycle for Pipeline Service

1975 ◽  
Author(s):  
T. C. Heard
Keyword(s):  
Ambient Temperature ◽  
Gas Turbine ◽  
Combined Cycle ◽  
Drive System ◽  
Paper Briefly ◽  
Preliminary Study ◽  
Gas Turbine Cycle ◽  
Cycle Efficiency ◽  
Standard Gas ◽  
Regenerative Cycle

The combined steam and gas turbine cycle provides the highest efficiency turbine system available today. In view of the rapidly escalating value of fuel the combined cycle therefore merits a review for pipeline applications. Such a review reveals the combined cycle has a number of advantages. First, the combined cycle efficiency is significantly higher than the efficiency of a standard regenerative cycle gas turbine. Second, and contrary to the characteristics of a standard gas turbine, the efficiency at a given load improves significantly as the ambient temperature increases, so that the combined cycle would be applicable in hot climates. Third, the adjustable speed capability of the combined cycle meets the usual pipeline service requirements. This paper briefly presents the results of a preliminary study of a combined cycle single drive system as it might be utilized in a gas pipeline station.

Effect of Water-Cooling Turbine Blades on Advanced Gas Turbine Power Systems

1977 ◽  
Author(s):  
B. V. Johnson ◽  
A. J. Giramonti ◽  
S. J. Lehman
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Pressure Ratio ◽  
Turbine Blades ◽  
Combined Cycle ◽  
Air Cooling ◽  
Water Cooling ◽  
Gas Turbine Blades ◽  
And Performance ◽  
Cycle Efficiency

A study was conducted to determine what benefits in cycle efficiency and performance could be obtained with water-cooled gas turbine blades. Water cooling was compared against various degrees of air cooling and the ultimate limit of no cooling. Performance studies were conducted for both combined gas turbine-steam cycles and simple gas turbine cycles with temperatures at the inlet to the first turbine blade row from 1478 K (2200 F) to 1922 (3000 F) and compressor pressure ratios from 12 to 28. Results for both types of cycles indicated that absolute efficiencies 1 to 3 percentage points greater and power output per unit airflow 5 to 25 percent greater than could be obtained with water-cooled blades compared to air-cooled blades. For a given cooling scheme and pressure ratio, highest efficiencies were obtained at 1700 K (2600 F) for the simple cycle and 1922 K for the combined cycle.

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