clear; clc; printf("\t\t\tProblem Number 3.16\n\n\n"); // Chapter 3 : The First Law Of Thermodynamics // Problem 3.16 (page no. 116) // Solution //In problem 3.15, p1=100; //Unit:psia //Initial pressure t1=950; //Unit:Fahrenheit //Temperature at pressure p1 p2=76; //Unit:psia //Final pressure t2=580; //Unit:Fahrenheit //Temperature at pressure p2 v1=4; //Unit:ft^3/LBm //Specific volume at inlet conditions v2=3.86; //Unit:ft^3/LBm //Specific volume at outlet conditions Cv=0.32; //Unit:Btu/(LBm*R) //Specific heat for constant volume process T1=t1+460; //Unit:R //Temperature at pressure p1 T2=t2+460; //Unit:R //Temperature at pressure p2 J=778; //J=Conversion factor gc=32.174; //Unit: (LBm*ft)/(LBf*s^2) //gc is constant of proportionality g=gc; //Unit:ft/s^2 //g=The local gravity //Z1=Inlet position //Unit:m //V1=Inlet velocity //Unit:m/s //Z2=Outlet position //Unit:m //V2=Outlet velocity Unit:m/s //u1=internal energy //energy in //u2=internal energy //energy out //Energy equation is given by //((Z1/J)*(g/gc)) + (V1^2/(2*gc*J)) + u1 + ((p1*v1)/J) + q = ((Z2/J)*(g/gc)) + (V2^2/(2*gc*J)) + u2 + ((p2*v2)/J) + w/J; //Unit:Btu/LBm //In 3.15, the elevation of the pipe at section 1 makes Z1 = 0 // Also no work crosses the boundaries of the system, the energy equation is reduced to //u1 + ((p1*v1)/J) + q = u2 + ((p2*v2)/J) + ((Z2/J)*(g/gc)) //In problrm 3.16, Z2=100; //Given //Unit:ft //Outlet position //u2-u1=Cv*(T2-T1) //For a constant volume process //u2-u1=Chnage in internal energy //So, q=Cv*(T2-T1) + (p2*v2*144)/J - (p1*v1*144)/J + ((Z2/J)*(g/gc)) ; //q=heat transfer //1 ft^2=144 in^2 //Unit:Btu/LBm printf("%f Btu/LBm heat is transferred from the gas \n",q); //For this problem , neglecting the elevation term leads to an insignificant error