Question 1)a) Define and describe Clausius statement of second law of thermodynamics.
b) Demonstrate that of all the engines operating between a given constant temperature source and a given constant temperature sink the efficiency of a reversible engine is maximum.
c) Air standard limited pressure cycle has compression ratio of 15 and compression begins at 0.1MPa and 40°C. The maximum pressure is limited to 6 MPa and total heat added is 1.675 MJ/kg. Calculate
(i) heat supplied at constant pressure
(ii) cut off ratio
(iii) Cycle efficiency
Question 2)a) Establish the inequality of clausius.
b) Steam at 30 bar and 350°C is supplied to a steam turbine in a practical regenerative cycle and the steam is bled at 4 bar pressure. The bled steam comes out as dry saturated steam and heats the feed water in an open type feed water heater to its saturated liquid state. The rest of the steam in the turbine expands to a condenser pressure of 0.1bar. Assuming the turbine efficiency to be same before and after bleeding, and neglecting the pump work determine
i) Turbine efficiency
ii) Steam quality at the inlet to the condenser
iii) The cycle efficiency
c) What are the differences between work transfer and heat transfer?
Question 3) List the three basic modes in which the heat is transferred.
b) Describe Fourier’s law of heat conduction
c) A heat engine operating between two reservoirs at 1000K and 300K is used to drive a heat pump which extracts heat from a reservoir at 300K at a rate twice that at which the engine rejects heat to it. If the efficiency of the engine is 40% of maximum possible and COP of the heat pump is 50% of maximum possible, what is the temperature of the reservoir to which heat pump rejects heat? What is the rate of heat rejection from the heat pump if the rate of heat supply to the heat engine is 50 kw.