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clc;
clear;
//Example 3.32
k=0.630 //W/(m.K
Beta=3.04*10^-4 //K^-1
rho=1000 //kg/m^3
mu=8.0*10^-4 //[kg/(m.s)]
Cp=4.187 //kJ/(kg.K)
g=9.81 //[m/(s^2)]
Tw=313 //[K]
T_inf=298 //[K]
dT=Tw-T_inf //[K]
D=20 //[mm]
D=D/1000 //[m]
Ngr=9.81*(rho^2)*Beta*dT*(D^3)/(mu^2) //Grashoff number
Cp1=Cp*1000 //[J/kg.K]
Npr=Cp1*mu/k //Prandtl number
//Average nusselt number is
Nnu=0.53*(Ngr*Npr)^(1.0/4.0)
h=Nnu*k/D //[W/ sqm.K]
Q_by_l=h*%pi*D*dT //Heat loss per unit length [W/m]
printf("\nHeat loss per unit length of the heater is %f W/m",Q_by_l);
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