clear; clc; disp('Example 7.5'); // aim : To determine // the final condition of steam... // the change in specific entropy during hyperbolic process // Given values P1 = 2;// pressure, [MN/m^2] t = 250;// temperature, [C] P2 = .36;// pressure, [MN/m^2] P3 = .06;// pressure, [MN/m^2] // solution // (a) // from steam table s1 = 6.545;// [kJ/kg K] // at .36 MN/m^2 sg = 6.930;// [kJ/kg*K] sf2 = 1.738;// [kJ/kg K] sfg2 = 5.192;// [kJ/kg K] vg2 = .510;// [m^3] // so after isentropic expansion, steam is wet // hence, s2=sf2+x2*sfg2, where x2 is dryness fraction // also s2 = s1; // so x2 = (s2-sf2)/sfg2; // and v2 = x2*vg2;// [m^3] // for hyperbolic process // P2*v2=P3*v3 // hence v3 = P2*v2/P3;// [m^3] mprintf('\n (a) From steam table at .06 MN/m^2 steam is superheated and has temperature of 100 C with specific volume is = %f m^3/kg\n',v3); // (b) // at this condition s3 = 7.609;// [kJ/kg*K] // hence change_s23 = s3-sg;// change in specific entropy during the hyperblic process[kJ/kg*K] mprintf('\n (b) The change in specific entropy during the hyperbolic process is = %f kJ/kg K\n',change_s23); // In the book they have taken sg instead of s2 for part (b), so answer is not matching // End