clear; clc; printf("\t\t\tProblem Number 6.40\n\n\n"); // Chapter 6: The Ideal Gas // Problem 6.40 (page no. 299) // Solution // * or "star" subscripts to conditions in which M=1; // "0" subscript refers to isentropic stagnation //This problem will be solved by two methods(A and B) printf("Method A\n"); //By equations: k=1.4; //the specific heat ratio //k=cp/cv R=53.3; //gas constant //ft*lbf/lbm*R M=2.5; //mach number=the local velocity/velocity of sound printf("Solution for (a)\n"); // T/Tstar = (k+1)/(2*(1+((1/2)*(k-1)*M^2))) // Tstar/T0=2/(k+1) //Therefore, // (Tstar/T0)*(T/Tstar) = (T/T0)=1/(1+((1/2)*(k-1)*M^2)) T0=560; //absolute temperature or stagnation temperature //unit:R T=T0/(1+((1/2)*(k-1)*M^2)); //temperature at M=2.5 printf("The temperature is %f R\n\n",T); printf("Solution for (b)\n"); p=0.5; //static pressure //unit:psia // p0/p = (T0/T)^(k/(k-1)) p0=p*14.7*((T0/T)^(k/(k-1))); //pressure at M=2.5 //unit:psia printf("The pressure is %f psia\n\n",p0); printf("Solution for (c)\n"); gc=32.17; //Unit:(LBm*ft)/(LBf*s^2) //gc is constant of proportionality Va=sqrt(gc*k*R*T); //ft/s //local velocity of sound V=M*Va; //valocity at M=2.5 //unit:ft/s printf("The velocity is %f ft/s\n\n",V); printf("Solution for (d)\n"); v=(R*T)/(p*14.7*144); //ft^3/lbm //1 ft^2=144 in^2 //specific volume at M=2.5 printf("The specific volume is %f ft^3/lbm\n\n",v); printf("Solution for (e)\n"); //Mass velocity is definrd as the mass flow per unit area // m/A=(A*V)/(v*A)=V/v printf("The mass velocity is %f lbm/(s*ft^2)\n\n\n",V/v); //mass velocity at M=2.5 printf("Method B\n"); //By the gas tables: //table 6.5 gives M=2.5; //mach number=the local velocity/velocity of sound printf("Solution for (a)\n"); T0=560; //absolute temperature or stagnation temperature //T/T0=0.44444 T=T0*0.44444; //temperature at M=2.5 printf("The temperature is %f R\n\n",T) printf("Solution for (b)\n"); p=0.5; //static pressure //p/p0=0.05853 p0=(p*14.7)/0.05853; //pressure at M=2.5 printf("The pressure is %f psia\n\n",p0); printf("Solution for (c)\n"); printf("As before %f ft/s\n\n",V) printf("Solution for (d)\n"); printf("As before %f ft^3/lbm\n\n",v) printf("Solution for (e)\n"); printf("As before %f lbm/(s*ft^1)\n",V/v)