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clear;
clc;
printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 5.1 Page 261 \n'); //Example 5.1
// Junction Diameter and Time Calculation to attain certain temp
//Operating Conditions
h = 400; //[W/m^2.K] Heat Convection coefficient
k = 20; //[W/m.K] Thermal Conductivity of Blade
c = 400; //[J/kg.K] Specific Heat
rho = 8500; //[kg/m^3] Density
Ti = 25+273; //[K] Temp of Air
Tsurr = 200+273; //[K] Temp of Gas Stream
TimeConstt = 1; //[sec]
//From Eqn 5.7
D = 6*h*TimeConstt/(rho*c);
Lc = D/6;
Bi = h*Lc/k;
//From eqn 5.5 for time to reach
T = 199+273; //[K] Required temperature
t = rho*D*c*2.30*log10((Ti-Tsurr)/(T-Tsurr))/(h*6);
printf("\n\n Junction Diameter needed for a time constant of 1 s = %.2e m \n\n Time Required to reach 199degC in a gas stream = %.1f sec ", D, t);
//END
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