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clear;
clc;
printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 10.2 Page 635 \n'); //Example 10.2
// Power Dissipation per unith length for the cylinder, qs
//Operating Conditions
Ts = 255+273 ;//[K] Surface Temperature
Tsat = 100+273 ;//[K] Saturated Temperature
D = 6*10^-3 ;//[m] Diameter of pan
e = 1 ;// eimssivity
stfncnstt=5.67*10^(-8) ;// [W/m^2.K^4] - Stefan Boltzmann Constant
g = 9.81 ;//[m^2/s] gravitaional constant
//Table A.6 Saturated water Liquid Properties T = 373 K
rhol = 957.9 ;//[kg/m^3] Density
hfg = 2257*10^3 ;//[J/kg] Specific Heat
//Table A.4 Water Vapor Properties T = 450 K
rhov = .4902 ;//[kg/m^3] Density
cpv = 1.98*10^3 ;//[J/kg.K] Specific Heat
kv = 0.0299 ;//[W/m.K] Conductivity
uv = 15.25*10^-6 ;//[N.s/m^2] Viscosity
Te = Ts-Tsat;
hconv = .62*[kv^3*rhov*(rhol-rhov)*g*(hfg+.8*cpv*Te)/(uv*D*Te)]^.25;
hrad = e*stfncnstt*(Ts^4-Tsat^4)/(Ts-Tsat);
//From eqn 10.9 h^(4/3) = hconv^(4/3) + hrad*h^(1/3)
//Newton Raphson
h=250; //Initial Assumption
while(1>0)
f = h^(4/3) - [hconv^(4/3) + hrad*h^(1/3)];
fd = (4/3)*h^(1/3) - [(1/3)*hrad*h^(-2/3)];
hn=h-f/fd;
if((hn^(4/3) - [hconv^(4/3) + hrad*hn^(1/3)])<=.01)
break;
end;
h=hn;
end
q = h*%pi*D*Te;
printf("\n Power Dissipation per unith length for the cylinder, qs= %i W/m",q);
//END
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