//Chemical Engineering Thermodynamics //Chapter 4 //Second Law of Thermodynamics //Example 4.1 clear; clc; //Given //Basis: 1 Kg of steam //P1 = 30;Intial pressure in Kgf/cm^2 //P2 = 3;Final pressure in Kgf/cm^2 //T = 300;//Operating temperature //From figure A.2.8, H1 = 715;//Initial enthalpy of steam in Kcal/Kg H2 = 625;//Final enthalpy of steam in Kcal/Kg S1 = 1.56;//Initial entropy of steam in Kcal/Kg K S2 = 1.61;//Final entropy of steam in Kcal/Kg K Q = -1;//heat loss in Kcal/Kg To = 298;//The lowest surronding temperature in K //To calculate the effectiveness of the process W = (-(H2-H1)+Q);//Actual work output by the turbine in Kcal //The maximum or available work can be calculated from equation 4.14 del_B = -((H2-H1)-(To*(S2-S1)));// Maximum work that can be obtained in Kcal E = (W/del_B)*100; mprintf('The effectiveness of the process is %f percent',E); //end