ME 405: Thermal Systems Design Washington State University Homework Set 3 Due Date: September 27, 2017 Note: Follow the Rubrics posted on the class website. Show complete and detail work for FULL CREDIT. This is a reasonably long problem, and you should get started ASAP. Group work is highly encouraged, but everyone should submit their own work for this homework. Cheating of any kind will not be tolerated in this class. Solve the problem discussed in the class before starting this long problem. For second law efficiency calculation, work on example problem 3.16. Show at least 10 points in all plots. Assume any reasonable value not provided in the problem definition. Problem Definition: A steam power plant operates on the reheat-regenerative Rankine cycle with a closed feedwater heater. Steam enters the turbine at 12 MPa and 5500C at a rate of 50 kg/sec and is condensed in the condenser at a pressure of 20 kPa. Steam is reheated at 5 MPa to the inlet temperature of the first turbine. Some steam is extracted from the low pressure turbine at 1 MPa, is completely condensed in the closed feedwater heater, and pumped to boiler pressure before it mixes with the feedwater at the same pressure. Assuming an isentropic efficiency of 90% for both the turbines and the pumps. (a) Draw the T-s diagram for the aforementioned system. (b) List all thermodynamic properties (temperature, pressure, specific volume, specific internal energy, specific enthalpy, entropy) for all state points in a table for T5 = 5500C. Find the first law and second law efficiency of the system. (c) Parametric Variation: Find the first law efficiency of the system as a function of turbine inlet temperature. Present your results in graphical form with appropriate discussion. (d) Parametric Variation: Find the second law efficiency as a function of turbine entry temperature. Present your results in graphical form with appropriate discussion. (e) List all assumptions used in this analysis.