blob: 29f619d7f510003422af3eaa770716aa5bb5267e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
|
clear all;
clc;
// A Textbook on HEAT TRANSFER by S P SUKHATME
// Chapter 2
// Heat Conduction in Solids
// Example 2.4
// Page 32
printf("Example 2.4, Page 32 \n\n")
Ti = 300; //Internal temp of hot gas in degree Celsius
OD = 0.1; //Outer diameter of long metal pipe in meters
ID = 0.04; //Internal diamtere of long metal pipe in meters
ki = 0.052; //thermal conductivity of mineral wood in W/mK
To = 50; //Outer surface temperature in degree celsius
hi = 29; //heat transfer coefficient in the inner side in W/m^2 K
ho = 12; //heat transfer coefficient in the outer pipe W/m^2 K
//Determination of thickness of insulation
function[f] = thickness(r)
f = r*(10.344 + 271.15*log(r*(0.05)^-1))-11.75
funcprot(0);
endfunction
r = 0.082;
while 1
rnew = r - thickness(r)/diff(thickness(r));
if rnew == r then
r3 = rnew;
break;
end
r = rnew;
end
t = r3 - OD/2;
printf("\n Thickness of insulation = %f cm",t*100);
//Heat loss per unit length
q = 600*(22/7)*r3;
printf("\n Heat loss per unit length = %.1f W/m",q);
|
