Steam at 200 bar, 760°C enters the throttle of a reheater engine and expands to 10 bar. At this point it leaves the engine, enters the reheater, and returns at 9 bar, 600°C, expansion then occurs to the condenser pressure of 0.5 bar (hf = 138 kJ/kg) on the basis of flow of 1 kg steam. Find (a) W and e of the cycle, (b) W, e, and m for the ideal engine, (c) In the actual engine the steam enters the reheater at 10 bar, 300°C and later expands to a saturated state at the exhaust to the condenser, find W, e and m.

Consider a cylinder of a gasoline engine at the beginning of the compression cycle, duringwhich a fuel/air mixture (for our purposes mostly composed of nitrogen and oxygen, i.e.an ideal gas of diatomic molecules) at 300 K and 1 bar is compressed down to one-tenthvolume (compression ratio of 10:1). Assume that the compression is rapid so no heatexchange occurs with the environment. Calculate the pressure and the temperature ofthe compressed gas. In a diesel engine, the compression ratios are typically much higher;redo the same calculation with a compression ratio of 20:1.

Example-2 A Regenerative Gas-Turbine cycle operates under pressure ratio of 9. The compressor inlet conditions are 18°C and 1 bar and its efficiency is 85%. The thermal ration of the heat exchanger is 80%. Heat is added to the compressed air after leaving the heat exchanger till its temperature became 900°C. The air then expands adiabatically in a 75% efficient turbine. If the air mass flow rate not exceeds 10 kg/s, determine the rate of heat added, the turbine work, the back work ratio, and the cycle thermal efficiency.

In a steady-state operating power plant, saturated liquid H2O at 122 deg C is fed to a boiler at 3.756 m/s through a pipe (0.03 m diameter). It leaves the boiler at 9 bar and 88.7 m/s. Then, it enters the turbine through a constant 0.13 m diameter pipe. The exit pipe of the turbine is 0.3 m in diameter and T = 310ºC while P = 1.37 bar. If 2.5 kg/s water is fed and there is change in KE, prove that the fluid enters the turbine at 637.06 deg C.