clc; clear; printf("\n Example 12.4\n"); u=3.5; //Velocity of air d=25e-3; //Diameter of the pipe l=6; //Length of the pipe T1=290; //Temperature at enterance T2=350; //Temperature at exit rho=29/22.4*273/310; //density of air at 310 K Meu=0.018e-3; //Viscosity of air at 310 K //Taking the physical properties at 310 K and assuming that fully developed flow exists Cp=1.003e3; //heat capapcity k=0.024; //Thermal conductivity Re=d*u*rho/Meu; Pr=Cp*Meu/k; printf("\n (a) Reynolds analogy"); h1=0.032*(Re^-0.25)*Cp*rho*u;//....Equation 12.139 printf("\n h = %.2f W/m^2 K",h1); // on solving we get final equation as theta_dash1=350-10^(log10(60)-(239.88*h1*1e-3/2.303)); printf("\n The outlet temperature = %.1f K",theta_dash1) printf("\n\n (b) Taylor Prandtl Equation"); h2=0.032*(Re^-0.25)*(1+2*Re^(-1/8)*(Pr-1))^-1*Cp*rho*u; printf("\n h = %.2f W/m^2 K",h2); // on solving we get final equation as theta_dash2=350-10^(log10(60)-(239.88*h2*1e-3/2.303));//....Equation 12.140 printf("\n The outlet temperature = %.1f K",theta_dash2) printf("\n\n (c) Universal velocity profile equation"); h3=0.032*(Re^-0.25)*(1+0.82*Re^(-1/8)*((Pr-1)+log(0.83*Pr+0.17)))^-1*Cp*rho*u;//...equation 12.141 printf("\n h = %.2f W/m^2 K",h3); // on solving we get final equation as theta_dash3=350-10^(log10(60)-(239.88*h3*1e-3/2.303)); printf("\n The outlet temperature = %.1f K",theta_dash3) printf("\n\n (d) Nu=0.023*Re^0.8*Pr^0.33"); h4=k/d*0.023*Re^0.8*Pr^0.33; printf("\n h = %.2f W/m^2 K",h4); // on solving we get final equation as theta_dash4=350-10^(log10(60)-(239.88*h4*1e-3/2.303)); printf("\n The outlet temperature = %.1f K",theta_dash4)