Performance Optimization of a Gas Turbine Power Plant Based on Energy and Exergy Analysis

Page 1

Mechanics, Materials Science & Engineering, January 2016 – ISSN 2412-5954

Performance Optimization of a Gas Turbine Power Plant Based on Energy and Exergy Analysis Ghamami M.1, a, Fayazi Barjin A.1, Behbahani S.1 1 – Department of Mechanical Engineering, Isfahan University Technology, Isfahan, Iran a – Mghamazi@ut.ac.ir

Keywords: Gas turbine, Exergy, Multi-objective, optimization, Fireflies algorithm, thermoflow.

Abstract. The purpose of this study is energetic and exergetic analysis of combined cycle power plant, study of the variables that affect the efficiency and performance and provide a solution to improve the efficiency and performance of the gas turbine. Therefore, after modeling gas cycle, the impact of environmental conditions and performance of gas turbine cycle will be checked, eventually we achieve two objective optimization of gas cycle that optimized by firefly algorithm in six cold months of the year. The objective functions are exergy efficiency and cost of the gas cycle maintenance, fuel cost and destroyed exergy cost. The proposed optimized result show increase in net output power of the gas cycle, energy and exergy efficiency and decrease in air pollution amount.

Introduction. Gas turbine is one of the power generating machines that have been widely used in various industries such as power plants, refineries and oil and gas industries. Since a high percentage of the power requirements of the country, is provided in the gas power plants and due to the fact that fossil fuels are the energy requirements of these power plants, thus the performance improvement of these power plants is very important. From about 70 years before gas turbines have been used to generate electricity, in the last twenty years the production of these type of turbines has increased by twenty times. Thermodynamic Simulator of gas cycle and combined cycle, is a useful tool to predict the behavior of each components of the cycle, by which the basic parameters of the processes in the cycle can be obtained. Exergy analysis is a good way to evaluate the quality of the energy with the aid of laws of conservation of mass and the first law of thermodynamics, and is on the basis of the second law of thermodynamics. The tool is used for design, analysis and optimization of thermal systems. The main objective of exergy analysis, finding solutions to eliminate or reduce thermodynamic defects in the processes. We can reduced exergy destruction by identifying the irreversibility factors and situation. Many studies have been done in this field, research done in this field can be mentioned the following: Siddiqui et al. [1] In their article they simulated a 100 MW gas cycle of one of the power plants in Iran is hot and dry regions ,by thermoflow software ,and investigated the effect of steam injection into the combustion chamber based on the exergy concept in order to improving gas turbine cycle. Sadeghi et al. [2] they studied and simulated the effects of light and heavy fuel on operational parameters of the gas turbine and combined cycle in Kazeroon power plant. Kim and Hwang [3] examined the performance of a gas turbine with recovery in half-load situation, by considering and comparing different mechanisms to control the turbine. Salary et al. [4] have studied exergy analysis of 112 MW Power Plant in Ahvaz Zergan. They optimized the cycle by increasing the turbine inlet temperature in terms of energy and exergy. Abdul Khaliq [5], used exergy method to analyze gas turbine cycle with inlet air cooling and has shown that most exergy destruction occurs in the combustion chamber, he also showed that by use of cooling the compressor inlet air, energy efficiency and the cycle Exergy will be increased. Ehyaei et al. [6] at the same time studied exergic, economic and enviromental analysis affected by Fog cooling system in the gas cycle of Rajayee power plant. Sanaye and Jafari [7] work in optimizing field, they have examined effect of inlet air cooling in gas turbine cycle by absorption refrigeration. The two-

MMSE Journal. Open Access www.mmse.xyz


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.