Q1: Steam at 2 Mpa and 250 C is expanded isentropically to 0.36 Mpa and it is then further expanded hyporbolically to 0.06 Mpa. Using steam table to determine 1. The final condition of the steam 2. The change in specific entropy during the hyperbolic process.

Entropy and ideal steady devices 1. H2O flows through a reversible adiabatic turbine. The inlet condition is 1000 F and 400 psia. The outlet condition is 10 psia. The turbine produces 100 hp. Neglecting kinetic and potential energy a. Draw the process curve on a T-s diagram. Show the saturation dome and label the inlet and exit states b. Find the enthalpy and entropy at the inlet c. Find the enthalpy at the exit d. Compute the mass flow rate e. Compute the rate of entropy generation

Q4. A piston-cylinder device whose piston is resting on top of a set of stops initially contains 0.5 kg of helium gas at 100 kPa and 25°C. The mass of the piston is such that 500 kPa of pressure is required to raise it. How much heat must be transferred to the helium before the piston starts rising? Cp = 3.11 kJ/kg K..**