Consider a regenerative gas-turbine power plant with two stages of compression and two stages of expansion. The overall pressure ratio of the cycle is 9. Argon enters each stage of the compressor at 300 K and each stage of the turbine at 1200 K. Assuming constant specific heats, determine the minimum mass flow rate of argon needed to develop a net power output of 110 MW. The properties of argon at room temperature are cp = 0.5203 kJ/kg-K and k= 1.667. The minimum mass flow rate of argon is [ kg/s.

If one measurement is conducted in the four processes and shows that the pressure ratio (P3/P2)in the adiabatic expansion is 1.2 times the pressure ratio (P4/P1) in the adiabatic compression, can you justify if it is a Carnot engine? Please give your reason

The 7FA gas turbine manufactured by General Electric is reported to have an efficiency of 35.9 percent in the simple-cycle mode and to produce 159 MW of net power. The pressure ratio is 14.7 and the turbine inlet temperature is 1288°C. The mass flow rate through the turbine is 1,536,000 kg/h. Taking the ambient conditions to be 20°C and 100 kPa, determine: (a)  the isentropic efficiency of the turbine and the compressor, (b)  the thermal efficiency of this gas turbine if a regenerator with an effectiveness of 80 percent is added. Answers: (a) 0.849, 0.924 (b) 0.496

Consider a reversible Carnot cycle with 1.75 mol of ideal gas with Cv = 3R/2 as the working substance. The initial isothermal expansion occurs at the hot reservoir temperature of Thot = 920. K from an initial volume of 4.00 L (Va) to a volume of 11.50 L (Vb). The system then undergoes an adiabatic expansion until the temperature falls to Tcold = 375 K. The system then undergoes an isothermal compression and subsequent adiabatic compression until the initial state described by Ta = 920. K and Va = 4.00L is reached. a. Calculate Vc and Vd. b. Calculate w for each step in the cycle and the total cycle. c. Calculate the efficiency, ε, and the amount of heat that is extracted from the hot reservoir to do 1.00 kJ of work in the surroundings.