blob: 30fc913b8cde8ad5748463083ff5bb414ab27ef5 (
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
|
// Theory and Problems of Thermodynamics
// Chapter 5
//Second Law of Thermodynamcis
// Example 17
clear ;clc;
//Given data
T1 = 263.15 // temperature of supercooled liquid water in K
T2 = 273.15 // final temperature of liquid water in K
Cp = 4.2 // specific heat(Isobaric) in kJ/kg K
Lw = 333.43 // latent heat of fusion of water at 0 *C in kJ/kg
// Calculations for determining mass of water
deff('y=mass(X)', 'y = Cp *(T2 - T1) - Lw * X') // Energy balance
X = fsolve(0,mass) // Mass of water solified in kg
// entropy change for system from T1 to T2 temperature
S1 = Cp*log(T2/T1)
// entropy change for system for phase change from liquid to ice
S2 = Lw*X/T2
S = (S1 - S2)*1e3 // Total entrophy change in J/K
// Output Results
mprintf('The mass of water which solidifies = %4.3f kg', X)
mprintf('\n The entrophy change associated = %6.4f J/K', S)
|
