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Thermodynamic analysis of a combined cycle power plant located in Jordan: A case study

Bataineh Khaled, Khaleel Bara A.

Archives of Thermodynamics

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2020

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Vol. 41, no 1

95--123

EN

Efficiency and electrical power output of combined cycle power plants vary according to the ambient conditions. The amount of these variations greatly affects electricity production, fuel consumption, and plant incomes. Obviously, many world countries have a wide range of climatic conditions, which impact the performance of power plants. In this paper, a thermodynamic analysis of an operating power plant located in Jordan is performed with actual operating data acquired from the power plant control unit. The analysis is performed by using first and second laws of thermodynamics. Energy and exergy efficiencies of each component of the power plant system are calculated and the effect of ambient temperature on the components performance is studied. The effects of gas turbine pressure ratio, gas turbine inlet temperature, load and ambient conditions on the combined cycle efficiency, power outputs and exergy destruction are investigated. Energy and exergy efficiencies of the combined cycle power plant are found as 45.29%, and 42.73% respectively when the ambient temperature is 34°C. Furthermore, it is found that the combustion chamber has the largest exergy destruction rate among the system components. The results showed that 73% of the total exergy destruction occurs in the combustion chamber when the ambient temperature is 34°C. Moreover, the results show that the second major exergy loss is in HRSC. The results show that the energy and exergy efficiency of the combined cycle power plant decreases as the ambient temperature increases. According to the calculation results, improvement and modification suggestions are presented.

2

Exergy and exergo-economic based analysis of a gas turbine power generation system

Mousafarash A., Ameri M.

Journal of Power Technologies

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2013

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Vol. 93, nr 1

44--51

EN

In this research study, energy, exergy and exergo-economic analysis of Montazer Ghaem gas turbine power plant which is located near Tehran, capital city of Iran is carried out. The results of this study reveal that the highest exergy destruction occurs in the combustion chamber (CC) where the large temperature difference is the major source of the irreversibility and also gas turbine and compressor are the other components followed by the combustion chamber. In addition, the effects of the gas turbine load variations and ambient temperature are conducted to see how system performance changes since the gas turbine is significantly affected by the ambient temperature which leads to a decrease in the net power output. The results of the load variation of the gas turbine show that a reduction in the gas turbine load, results a decrease in the exergy efficiency of the cycle as well as all the components. As it was expected, the effect of an increase in ambient temperature has a negative effect on the exergy efficiency of the cycle so this reason could be enhanced by using the gas turbine air inlet cooling methods. In addition, an exergo-economic analysis is conducted to determine the cost of exergy destruction in each component and to determine the cost of fuel. The results show that combustion chamber has the largest cost of exergy destruction like exergy analysis.

3

Thermodynamic modeling and second law based performance analysis of a gas turbine power plant (exergy and exergoeconomic analysis)

Ameri M., Enadi N.

Journal of Power Technologies

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2012

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Vol. 92, nr 3

183--191

EN

It this research paper, a complete thermodynamic modeling of one of the gas turbine power plants in Iran is performed based on thermodynamic relations. Moreover, a complete computer code is developed for the simulation purposes using the Matlab software. To assess the system performance, exergy and exergo-economic analysis are conducted to determine the exergy destruction of each component and cost of each flow line of the system. A complete parametric study is also carried out to study the effect of some design parameters such as exergy efficiency and total cost of exergy destruction on the system performance variation. The exergy analysis results have revealed that combustion chamber (CC) is the most exergy destructor component compared to other cycle components. Also, its exergy efficiency is less than other components which is due to the high temperature difference between working fluid and burner temperature. In addition, it was found that by an increase in the TIT (gas turbine inlet temperature), the exergy destruction of this component can be reduced. On the other hand, the cost of exergy destruction, which is a direct function of exergy destruction, is high for combustion chamber. The effects of design parameters on exergy efficiency have shown that an increase in the air compressor pressure ratio and TIT increases the total exergy efficiency of the cycle. Furthermore, the results have revealed that by an increase in the TIT for about 350 K the cost of exergy destruction can be decreased for about 22%. Therefore, TIT is the best option to improve the cycle losses.

4

Application of Exergy Analysis to Textile Printing Process

Cay A., Ozguney A. T., Yavas A.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 6A (95)

37--42

EN

This study reveals an exergetic analysis of the reactive and pigment printing processes. Exergy models of the printing processes were formed and each step examined in terms of exergetic parameters. In the printing machine, the reactive printing process led to a higher specific exergy use due to the penetration requirement of the printing paste. The exergy efficiency in the subsequent drying after printing was found to be independent of the printing method, but affected by the fabric structure, which was calculated to be between 3.8% and 4.8%. In the fixation step, pigment printing provided the highest exergy efficiency, calculated to be 2.15%, due to the direct heating of the fixation air. It was observed for the fixation step that the boiler unit of the steaming process and the burner of the hot air fixation process led to the highest exergy destruction rates. The total exergy destruction rate in pigment printing was found to be higher than in the washing and final drying stages of reactive printing alone; thus, it was shown that the exergetic improvement of the post-washing and drying of reactive printing is of great importance.

PL

Praca przedstawia analizę zużycia energii w procesie druku reaktywnego i pigmentowego. Skonstruowano modele egzergetyczne procesu druku i przeanalizowano każdy krok pod względem parametrów wpływających na egzergię. W maszynie drukarskiej, reaktywny proces drukowania prowadzi do podwyższenia egzergii w wyniku zapotrzebowania na penetrację pasty drukarskiej. Stwierdzono, że wydajność egzergii w procesie suszenia po drukowaniu jest niezależna od metody drukowania, zależy natomiast od struktury materiału i obliczono, że zawiera się ona w granicach 3.8% do 4.8%. W procesie stabilizacji drukowanie pigmentowe prowadzi do najwyższej egzergii, która wynosi 2.15%, w wyniku bezpośredniego utrwalania w powietrzu. Stwierdzono, że zastosowanie dla fazy utrwalania kotła parowego stosowanego w procesie parowania i palnika w procesie wysokotemperaturowego utrwalania prowadzi do najwyższych wartości destrukcji egzergii. Stwierdzono, że przy druku reaktywnym całkowita wartość destrukcji egzergii w procesie druku pigmentowego była wyższa niż w fazach prania i końcowego suszenia. Wynika z tego, że przy druku reaktywnym bardzo ważnym jest egzergetyczne polepszenie końcowej fazy prania i suszenia.