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clear;
clc;
printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 9.5 Page 592 \n'); //Example 9.5
// Heat Loss from pipe per unit of length
// Heat Loss if air is filled with glass-fiber blanket insulation
//Operating Conditions
To = 35+273 ;//[K] Shield Temperature
Ti = 120+273 ;//[K] Tube Temperature
Di = .1 ;//[m] Diameter inner
Do = .12 ;//[m] Diameter outer
L = .01 ;//[m] air gap insulation
//Table A.4 Air Properties T = 350 K
k = 30*10^-3 ;//[W/m.K] Conductivity
uv = 20.92*10^-6 ;//[m^2/s] Kinematic Viscosity
al = 29.9*10^-6 ;//[m^2/s] alpha
be = 2.85*10^-3 ;//[K^-1] Tf^-1
Pr = .7 ;// Prandtl number
g = 9.81 ;//[m^2/s] gravitational constt
//Table A.3 Insulation glass fiber T=300K
kins = .038 ;//[W/m.K] Conductivity
Lc = 2*[2.303*log10(Do/Di)]^(4/3)/((Di/2)^-(3/5)+(Do/2)^-(3/5))^(5/3);
Ra = g*be*(Ti-To)/al*Lc^3/uv;
keff = .386*k*(Pr/(.861+Pr))^.25*Ra^.25;
q = 2*%pi*keff*(Ti-To)/(2.303*log10(Do/Di));
//From equatiom 9.58 and 3.27
qin = q*kins/keff;
printf("\n Heat Loss from pipe per unit of length is %i W/m \n Heat Loss if air is filled with glass-fiber blanket insulation %i W/m",q,qin);
//END
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