// Example 10_8 clc;funcprot(0); // Given data m=2.80;// lbm/s // Station 1 p_1=100;// psia T_1=500;// °F h_1=1279.1;// Btu/lbm s_1=1.7087;// Btu/lbm.R // Station 2 p_2=10.0;// psia p_2s=p_2;// psia s_2f=0.2836;// Btu/lbm.R s_2fg=1.5043;// Btu/lbm.R s_2=s_1;// Btu/lbm.R h_2f=161.4;// Btu/lbm h_2fg=982.1;// Btu/lbm h_2s=1091.6;// Btu/lbm // Ground state x_0=0;// The quality of steam T_0=70.0;// °F s_0=0.0746;// Btu/lbm.R h_0=38.1;// Btu/lbm g_c=32.174;// lbm.ft/lbf.s^2 g=32.174;// ft/s^2 // Calculation // (a) V_1=0;// ft/s Z_2=0;// ft Z_1=Z_2;// ft V_2s=[2*g_c*(h_1-h_2s)*778.16]^(1/2);// ft/s V_2=(95/100)*V_2s;// ft/s h_2=h_1-((V_2^2)/(2*g_c*778.16));// Btu/lbm x_2=(h_2-h_2f)/h_2fg;// The quality of steam s_2=s_2f+(x_2*s_2fg);// Btu/lbm.R a_f1=(h_1-h_0)-((T_0+459.67)*(s_1-s_0))+(V_1^2/(2*g_c*778.16))+((g*Z_1)/g_c);// Btu/lbm // (b) a_f2=(h_2-h_0)-((T_0+459.67)*(s_2-s_0))+(V_2^2/(2*g_c*778.16))+((g*Z_2)/g_c);// Btu/lbm // (c) I=m*(a_f1-a_f2);// Btu/s printf("\n(a)The inlet specific flow availability,a_f1=%3.0f Btu/lbm \n(b)The exit specific flow availability,a_f2=%3.0f Btu/lbm \n(c)The irreversibility rate inside the nozzle,I=%2.1f Btu/s",a_f1,a_f2,I); // The answer vary due to round off error