Chapter 8, Problem 8.25CU

3.1 Describe with the aid of a plant layout and p-v and T-s diagrams, the working of simple closed circuit, ideal and actual constant pressure gas turbine cycles.

A 20 mw steam power plant working on a rankine cycle operates between pressures of 80 bar and 0.1 bar. The maximum cycle temperature is 600 °c if the steam turbine efficiency is 90% calculate thermal efficiency of the cycle and mass flow rate of the steam.

The efficiency of a Carnot Cycle can be determined using only the hot and cool temperature True False

The coefficient of performance of a reversed carnot cycle is 5.35 when refrigeration is done at 255 K, s= 0.38 kJ/K during the isothermal heat interactions. Find a) The heat added in the cycle. b) The temperature at which heat is added. c) The network.

A steam power plant works between 40 bar and 0.05 bar. If the steam supplied is dry saturated and thecycle of operation is Rankine, find :(i) Cycle efficiency (ii) Specific steam consumption

1.) A reversible cycle executed by 1 mol of an ideal gas for which Cp = (5/2)R and Cv = (3/2)R consists of the following: • Starting at T1 = 700K and P1 = 1.5 bar, the gas is cooled at constant pressure to T2 = 350K • From 350K and 1.5 bar, the gas is compressed isothermally to pressure P2. • The gas returns to its initial state along a path for which PT=constant What is the thermal efficiency of the cycle?

1. Derive the final temperature of the following cycles, in terms of initial temperature and ratios a. Otto Cycle b. Diesel Cycle c. Dual Cycle

6. The following image shows Carnot cycle beginning from the point A and returns back to A. a) Using adiabatic expansion and isothermal expansion, prove that this cycle (1-4) has no net change in entropy. (dS = 0) b) Prove that the efficiency of any machine is only dependent on the temperature difference of hot source and cold sink. work performed 71- heat absorbed fro hot source c) In an ideal heat engine, the cold sink is at 5 °C. If 250.0 kJ of heat is withdrawn from the hot source and 200.0 kJ of work is generated, what is the initial temperature of the hot source? Pressure p D Adiabat 1 Isotherm Adiabat Isotherm 3 Volume, V B

XX=50