Question

In: Mechanical Engineering

In a gas turbine plant, air is compressed through a pressure ratio of 6 from 15...

In a gas turbine plant, air is compressed through a pressure ratio of 6 from 15 ?C. It is then heated to the maximum permissible temperature of 750 ?C and expanded in two stages each of expansion ratio ?6, the air being reheated between the stages to 750 ?C. A heat exchanger allows the heating of the compressed air through 75 percent of the maximum range possible. Calculate the cycle efficiency, the work ratio and the net work output per kg of air. The isentropic efficiencies of the compressor and turbine are 0.80 and 0.85, respectively.

answer(0.324, 0.385, 152 kJ/kg)

Solutions

Expert Solution


Related Solutions

In a gas turbine plant, air is compressed from 1.01 bar and 15 ?C through a...
In a gas turbine plant, air is compressed from 1.01 bar and 15 ?C through a pressure ratio of 4. It is then heated to 650 ?C in a combustion chamber, and expanded back to atmospheric pressure. Calculate the cycle efficiency and work ratio if a perfect heat exchanger is employed. The isentropic efficiencies of the turbine and compressor are 0.85 and 0.80, respectively. ANSWER (0.319, 0.319)
A gas turbine plant consists of a compressor with a pressure ratio of 10, a combustion...
A gas turbine plant consists of a compressor with a pressure ratio of 10, a combustion chamber, and a turbine mounted on the same shaft as the compressor; the net electrical power of the unit is 20 MW. The inlet air conditions are 1.013 bar and 15 ?C and the maximum cycle temperature is 1100 K. The exhaust gases from the turbine are passed through a heat exchanger to heat water for space heating before passing to the chimney; by...
. In a gas turbine plant, air enters a compressor at atmospheric conditions of 15 ?C,...
. In a gas turbine plant, air enters a compressor at atmospheric conditions of 15 ?C, 1.0133 bar and is compressed through a pressure ratio of 10. The air leaving the compressor passes through a heat exchanger before entering the combustion chamber. The hot gases leave the combustion chamber at 800 ?C and expand through an HP turbine which drives the compressor. On leaving the HP turbine the gases pass through a reheat combustion chamber which raises the temperature of...
In a gas turbine with two-stage compression and expansion, the total pressure ratio is 12. Air...
In a gas turbine with two-stage compression and expansion, the total pressure ratio is 12. Air enters the compressor at a temperature of 320 K and the turbine at a temperature of 1320 K. The isanthropic efficiency of the compressors is 75%, the efficiency of the turbines is 87% and the regenerator is 78%. Considering the change of specific temperatures with temperature; a) back work rate, b) calculate the thermal efficiency of the cycle.
A gas turbine power plant operates on a Brayton cycles has a pressure ratio of 7....
A gas turbine power plant operates on a Brayton cycles has a pressure ratio of 7. Air enters the compressor at 300 K. The energy in the form of heat is transferred to the air in the amount of 950 kJ/kg. Using a variable specific heat for air and assuming the compressor isentropic efficiency is 83 percent and turbine isentropic efficiency is 85 percent. Determine the followings: (i) The highest temperature in the cycle [5 marks] (ii) The net work...
In a gas turbine of a thermoelectric plant a regenerator is used that preheats the air...
In a gas turbine of a thermoelectric plant a regenerator is used that preheats the air before it enters the combustion chamber. You have the options of a backflow heat exchanger or a shell heat exchanger and two tube passages. The air leaves the compressor at a temperature of 350 C and the exhaust gases have a temperature of 700 C. The mass flow in both cases is 5 kg / sec. The overall transfer coefficient is 75 w /...
. Air enters the compressor of a gas turbine power plant operating on Brayton cycle at...
. Air enters the compressor of a gas turbine power plant operating on Brayton cycle at 14.5 psia and 540° R. The pressure ratio across the turbine and compressor is same, which is equal to 6. Assume that the compressor work as 0.4 times the turbine work. Take K=1.4 a) Draw the T-S diagram of the cycle. [2] b) Calculate the maximum temperature in the cycle. [3] c) Calculate the cycle efficiency
15 g of nitrogen gas at STP are adiabatically compressed to a pressure of 21 atm...
15 g of nitrogen gas at STP are adiabatically compressed to a pressure of 21 atm . What is the final temperature of the gas? What is the work done on the gas? What is the heat input to the gas? What is the compression ratio Vmax/Vmin?
In a marine gas turbine unit a high-pressure turbine drives the compressor, and a low-pressure turbine...
In a marine gas turbine unit a high-pressure turbine drives the compressor, and a low-pressure turbine drives the propeller through suitable gearing. The overall pressure ratio is 4/1, and the maximum temperature is 650⁰C. The isentropic efficiencies of the compressor, High Pressure turbine, and Low Pressure turbine are 0.8, 0.83 and 0.85 respectively, and the mechanical efficiency of both shafts is 98%. Calculate the pressure entering the Low Pressure turbine when the air intake conditions are 1.01 bar and 25⁰C....
A gas turbine air- standard cycle operates between a low pressure of 14.7 Psia and a...
A gas turbine air- standard cycle operates between a low pressure of 14.7 Psia and a high pressure of 60 Psia. The temperature of the gas at the inlet to the compressor and turbine are 60 and 1000 respectively. If 40,000 ft3 /min. of air enter the compressor and assuming k=1.41, compute: a) The theoretical net power output, and b) The air – standard thermal efficiency
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT