A Mathematical Model for Predicting the Thermal Efficiency of a Gas Turbine Power Plant Using Dimensional Analysis Based on the Buckingham’s Pi Theorem

Author(s):  
Victor Chijioke Okafor ◽  
◽  
Princewill Kelechi Ejesu ◽  
Dennis Chukwunonye Chinweuba ◽  
Reginald Nnaemeka Nwakuba
Author(s):  
Saeed Farokhi

In a modern gas turbine power plant, the axial exhaust diffuser accounts for up to 10% of the generator power. An unshrouded rotor, due to its highly energetic tip clearance flow, improves the pressure recovery characteristic of the exhaust diffuser, while the power production within the blading suffers a loss as a result of the tip leakage flow. In this paper, these conflicting trends are thermodynamically investigated and nondimensional expressions are derived which facilitate the task of a gas turbine system designer. Conservatively, 1% thermal efficiency gain results from elimination of the last rotor tip clearance flow. The corresponding increase in thermal efficiency of a modern gas turbine power plant due to enhanced diffuser pressure recovery is less than one percent.


2021 ◽  
Vol 93 ◽  
pp. 01019
Author(s):  
G.A. Kilin ◽  
B.V. Kavalerov ◽  
A.I. Suslov ◽  
M.A. Kolpakova

Gas turbine units are widely used as a drive for a synchronous generator in a gas turbine power plant. The main problem here lies in the fact that the control systems of such gas turbine plants are transferred practically unchanged from their aviation counterparts. This situation leads to inefficient operation of the gas turbine power plant, which affects the quality of electricity generation. To solve this problem, it is necessary to improve the control algorithms for the automatic control systems of gas turbine plants. When solving this problem, gas turbine plants should be considered in interaction with other subsystems and units; for gas turbine power plants, this is, first of all, an electric generator and the electric power system as a whole. Setting up a control system is one of the most costly stages of their production, both in terms of finance and time. Especially time-consuming operations are non-automated manual configuration management system for developmental and operational testing. Therefore, it is proposed to use a software-modeling complex, on the basis of which it is possible to obtain a neural network mathematical model of a gas turbine power plant and conduct its tests.


2011 ◽  
Vol 189-193 ◽  
pp. 3007-3013 ◽  
Author(s):  
M.M. Rahman ◽  
Thamir K. Ibrahim ◽  
K. Kadirgama ◽  
R. Mamat ◽  
Rosli A. Bakar

This paper presents the effect of ambient temperature and operation conditions (compression ratio, turbine inlet temperature, air to fuel ratio and efficiency of compressor and turbine) on the performance of gas turbine power plant. The computational model was developed utilizing the MATLAB codes. Turbine work found to be decreases as ambient temperature increases as well as the thermal efficiency decreases. It can be seen that the thermal efficiency increases linearly with increases of compression ratio while decreases of ambient temperature. The specific fuel consumption increases with increases of ambient temperature and lower turbine inlet temperature. The effect of variation of SFC is more significance at higher ambient temperature than lower temperature. It is observed that the thermal efficiency linearly increases at lower compressor ratio as well as higher turbine inlet temperature until certain value of compression ratio. The variation of thermal efficiency is more significance at higher compression ratio and lower turbine inlet temperature. Even though at lower turbine inlet temperature is decrement the thermal efficiency dramatically and the SFC decreases linearly with increases of compression ratio and turbine inlet temperature at lower range until certain value then increases dramatically for lower turbine inlet temperature.


2018 ◽  
Vol 220 ◽  
pp. 03011
Author(s):  
T. Aurthur Vimalachandran ◽  
Andrey Yurievich Tkachenko ◽  
Viktor Nikolaevich Rybakov

A detailed parametric analysis was performed on entire performance cycle model of micro gas turbine power plant. The parametric analysis was studied using Russian Software named ASTRA. Evaluation of parameters on both design and operation condition was performed. The parameters focused here are power output, compression work, specific fuel consumption and thermal efficiency. Various stages such as use of Intercooler, Pre-heater and their optimal influence on thermodynamics were performed. The task was to optimize the maximum output in free turbine power by simulating various cycles of compressor pressure ratios for centrifugal compressor, ambient temperature in various altitude; air-fuel mix ratio and turbine inlet temperature. The results are analysed and presented in this article, the Analysis known as on-design analysis. The compressor uses 66% of turbine work output. The research analysis focuses on reducing the use of power output by compressor and maximizes the power output by free turbine. The results could be summarized as increase in gas turbine thermal efficiency does not always improve the gas turbine efficiency. Optimum power increase of up to 3% was improved and improvement in fuel efficiency improved about 4%.


2015 ◽  
Vol 137 (05) ◽  
pp. 58-59
Author(s):  
Lee S. Langston

This article discusses various features of supercharged gas turbine and supercharged analysis. One 400 MW supercharged gas turbine power plant variant analysed by Wettstein yielded a predicted thermal efficiency of 60 percent, rivaling current combined cycle values. The supercharged gas turbine power plant proposed by Wettstein is a semi-closed (SC) cycle. The SC cycle is an amalgamation of closed and open cycles. It consists of a gas turbine having an internal combustor for energy input to the cycle. With a SC cycle, a designer now has some of the best features of both open and closed to move SC power plant operation in different directions. With internal combustion, the SC cycle is not constrained by the temperature limitations of the closed cycle. The supercharged gas turbine power plant looks very promising. In another ASME paper, Wettstein shows how gas turbine supercharging could benefit marine propulsion.


2015 ◽  
Vol 76 (5) ◽  
Author(s):  
Alhassan Salami Tijani ◽  
Mohd Rashid Halim

The purpose of this paper is to study the performance of an existing open cycle gas turbine power plant at Putrajaya power station. At compressor inlet temperature of 298.90K, thermal efficiency of 31 % was observed for the existing or current cycle whiles the modified configuration yielded thermal efficiency of 45 %, this result in 14 % increase in thermal efficiency. At pressure ratio of 3.67, thermal efficiency of about 31.06% and 44% was recorded for the current cycle and regenerative cycle respectively. The efficiency of both cycles increase considerably with increase in pressure ratio, but at pressure ratio of about 7, only a small increase in efficiency for both cycles was observed. The optimum value of the efficiencies for both cycles that correspond to pressure ratio of 7 is 43.06 and 56% for the current cycle and the regenerative cycle respectively.


2019 ◽  
Vol 140 ◽  
pp. 05012
Author(s):  
Boris Kavalerov ◽  
Grigory Kilin ◽  
Evgeniy Zhdanovskiy

There are many problems connected with use of gas turbine units for electricity generation. The main problem is the gas turbine unit inefficient operation as a synchronous generator drive. To ensure the required quality of the generated electricity, which is largely determined by the nature of the transient processes of gas turbine unit, further improvement of control algorithms for automated control systems of gas turbine unit is required. In solving this problem, gas turbine unit should be considered in conjunction with other subsystems and units, for gas turbine power plants - this is, first of all, the electric generator and electric power industry in general. The process of tuning a gas turbine power plant control system is part of the test. Particularly time-consuming operations are manual tuning of the control system during experimental design and operational tests. Therefore, we propose to use a software-modeling complex, on the basis of which it is possible to obtain a neural network mathematical model of a gas turbine electro station and conduct its tests. In this case, in the process of testing the control system, the setup procedure is first performed on a mathematical model, then the settings obtained are checked using semi-bench testing, the final check of the decisions taken is carried out on a full-scale test bench, and data on the direct operation of a gas turbine power plant are also taken into account.


Author(s):  
Varuneswara Reddy Panyam ◽  
Devendra Dandotiya ◽  
Nitin Banker

Turbine inlet air cooling (TIAC) has long been the most commonly used method to improve the performance of gas turbine based power plants. It is particularly effective in regions with high ambient temperatures. With growing energy demands and higher ambient temperatures around the globe, it is important to look beyond cooling cycles like vapor-absorption and vapor-compression which have certain limitations. It is prudent to use a vapor-adsorption cycle for TIAC since the waste exhaust heat can be utilized as the power source for adsorption compressor, resulting increase in thermal efficiency of the power plant. Also, the scalability of adsorption cooling from mere Watts to hundreds of kW and its ability to function using lower temperature heat sources (as low as 60 °C) render it highly suitable for TIAC. In this paper, a gas turbine power plant and a TIAC system running on vapor-adsorption cycle are mathematically modelled and thermal analysis involving comparison of performance of the power plant with and without inlet air cooling at various ambient and desorption temperatures is presented. Performance parameters analyzed include net power output and thermal efficiency of the power plant and the COP of the chiller. The results show that vapor-adsorption system has huge potential to be integrated with gas turbine power plant for inlet air cooling.


Sign in / Sign up

Export Citation Format

Share Document