"ME 345 Spring 2021: Equations for WK6 Homework - Problem 5"

"Inputs"
epsilon = 0.8
sigma = 5.67E-8
T_sur = 298
T_infinity = 298
k = 0.089
h = 25
T_s1 = 800
r_1 = 0.06
Thickness_insulation = r_2 - r_1
 
$IFNOT Parametric Study
	r_2 = 0.08 
$ENDIF 
 
"Heat Transfer Per Unit Length of Pipe"
q_prime_cond = (T_s1 - T_s2)/R_prime_cond
q_prime_conv = (T_s2 - T_infinity)/R_prime_conv
q_prime_rad = (T_s2 - T_sur)/R_prime_rad
 
"Thermal Resistance Equations"
R_prime_cond = (ln(r_2/r_1))/(2*pi*k)
R_prime_conv = 1/(h*2*pi*r_2)
R_prime_rad = 1/(h_r*2*pi*r_2)
h_r = epsilon*sigma*(T_s2 + T_sur)*(T_s2^2 + T_sur^2)
 
 
"Energy Balance at T_s2"
q_prime_cond = q_prime_conv + q_prime_rad