Karaali, Rabi; Öztürk, İlhan Tekin

In this study, some improving methods of gas turbine cogeneration cycles are applied on a simple cogeneration cycle. These methods are preheating air, preheating air and fuel, inlet air cooling by using evaporative cooling and absorption cooling. These cogeneration systems are evaluated with respect to energy efficiency (energy utilization factor), exergetic efficiency, electric and heat power, electric-heat energy rate, artificial thermal efficiency and fuel energy saving ratio and are compared with each other. In these analyses, the thermodynamic parameters such as compressing ratio, air and fuel mass ratio and compressor inlet temperatures of the cycles are used. It is concluded that these parameters can be listed from most effective to least effective as air fuel ratio, pressure ratio and compressor inlet temperature. It is also concluded that the most efficient cycle is found to be the air-fuel preheated cycle for obtaining more electric power and less heat power, and the simple cycle is the most suitable one for obtaining more heat power and less electric power

AtıfTR Dizin1

İncele

Karaali, Rabi; Öztürk, Ilhan Tekin

In this paper, effects of the ambient conditions on performance of cogeneration cycles are analyzed by Using exergy analysis method. These cogeneration cycles are the simple cycle, the air preheating cycle, the air-fuel preheating cycle and the inlet air cooling cycle. Also; these cycles are evaluated thermodynamically for different air and fuel mass ratio and the performance of these cycles are compared. The electrical power generation increases about 10-15 % by decreasing the inlet air temperature of the compressor from 25 degrees C to 0 degrees C. However, the thermal power decreases about 10 % with decreasing inlet air temperature. During the summer, the electric power can be easilyincreased 2-7 % by injecting water into the inlet air of the compressor. The exergetic efficiency of cycles is decreased 11-13 %; by decreasing the compressor inlet air pressure from 101.3 kPa to 70.18 kPa. But this change decreases the electric power generation about 25 %. The highest exergy efficiency is obtained for the air-fuel preheated cycle. The simple cycle is the best among the four cycles to obtain high heat rate and heat exergy. The effects of all ambient conditions on these cycles are considered simultaneously, analyzed and compared With each other in this study.

AtıfWoS3

İncele

Karaali, Rabi; Oztürk, Ilhan Tekin

In this study, some improving methods of gas turbine cogeneration cycles are applied on a simple cogeneration cycle. These methods are preheating air, preheating air and fuel, inlet air cooling by using evaporative cooling and absorption cooling. These cogeneration systems are evaluated with respect to energy efficiency (energy utilization factor), exergetic efficiency, electric and heat power, electric-heat energy rate, artificial thermal efficiency and fuel energy saving ratio and are compared with each other. In these analyses, the thermodynamic parameters such as compressing ratio, air and fuel mass ratio and compressor inlet temperatures of the cycles are used. It is concluded that these parameters can be listed from most effective to least effective as air fuel ratio, pressure ratio and compressor inlet temperature. It is also concluded that the most efficient cycle is found to be the air-fuel preheated cycle for obtaining more electric power and less heat power, and the simple cycle is the most suitable one for obtaining more heat power and less electric power.

AtıfScopus6

İncele

Comakli, Omer; Comakli, Kemal; Ozdemir, Nesrin; Yilmaz, Mehmet

The goal of this work is to determine the optimum set of parameters by using the Taguchi method in vapour compression heat pump systems. The experimental apparatus consist of an air-to-liquid vapor compression heat pump, a water cooled condenser, a forced air evaporator, an electrical air and water heaters, and various measuring elements and other auxiliary equipments. Refrigerants R22, R407C, and five of their binary mixtures which contain about 0%, 25%, 50%, 75%, and 100% mass fractions of R407C were tested. To determine the effect of the chosen parameters on the system and optimum working conditions, an experimental design method suggested by Genichi Taguchi was used. The most effective parameters are found to be the condenser water mass flow rate for the coefficient of performance and to be condenser water inlet temperature for the exergetic efficiency.

AtıfWoS6

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