School of Mechanical and Building SciencesB.Tech- Chemical/Energy/Automotive/Mechanical EngineeringAssignment-1MEE204 Engineering Thermodynamics

1. A system executes a quasi-static process from an initial state 1 to a final state 2, absorbing 80 kJ of heat and expanding from 2.0 m3 to 2.25 m3 against a constant pressure of 1.5 bar. The system is brought back to its initial state by a non-quasi-static process, during which it rejects 100 kJ of heat. What is the work done during the second process? 2. Consider the system shown in the figure. The left chamber contains an ideal gas. The right chamber contains 2 kg of saturated liquid water at 1 bar. The gas is stirred, and the steam allowed to expand at constant pressure till it becomes dry saturated. Determine (a) change in internal energy of the ideal gas, (b) heat transferred across the diathermal wall, (c) stirrer work, and (d) work done by steam.

3. A centrifugal air compressor compresses 5 m3/min of gas from 10 N/cm2 to 70 N/cm2. The inlet and exit specific volumes are 0.8 m3/kg and 0.4 m3/kg respectively. The duct diameter is 10 cm at the inlet and 5 cm at the exit. Determine (a) rate of flow work, (b) mass flow rate, and (c) change in velocity.4. Cold air at 0oC and 1 bar, and a flow rate of 1 kg/s is mixed with a hot stream of air at 80oC and 2 bar to provide warm air at 25oC and 1 bar. The mixer is an adiabatic open system with rigid walls. Determine (a) flow rate of hot air, and (b) rate of entropy production.