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
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
/*
freesteam - IAPWS-IF97 steam tables library
Copyright (C) 2004-2009 John Pye
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/*
Based on IAPWS Formulation 2008 for the Viscosity of Ordinary Water Substance
*/
#define FREESTEAM_BUILDING_LIB
#include "viscosity.h"
static double mu0(double tau);
static double mu1(double del, double tau);
#define VISCOSITY_MUSTAR 1.0e-6 /* Pa-s */
#include <math.h>
static double mu0(double tau){
const double H[4] = {1.67752, 2.20462, 0.6366564, -0.241605};
int i;
double sum = 0;
for (i = 0; i < 4; i++){
sum += H[i] * ipow(tau, i) ;
}
return 100.0 / (sqrt(tau) * sum);
}
static double mu1(double del, double tau){
const double H[6][7] = {
{ 5.20094E-1, 2.22531E-1, -2.81378E-1, 1.61913E-1, -3.25372E-2, 0.0, 0.0},
{ 8.50895E-2, 9.99115E-1, -9.06851E-1, 2.57399E-1, 0.0, 0.0, 0.0},
{-1.08374, 1.88797, -7.72479E-1, 0.0, 0.0, 0.0, 0.0},
{-2.89555E-1, 1.26613, -4.89837E-1, 0.0, 6.98452E-2, 0.0, -4.35673E-3},
{ 0.0, 0.0, -2.57040E-1, 0.0, 0.0, 8.72102E-3, 0.0},
{ 0.0, 1.20573E-1, 0.0, 0.0, 0.0, 0.0, -5.93264E-4}
};
int i, j;
double sum = 0;
double tau1 = 0;
for (i = 0; i < 6; i++){
tau1 = ipow(tau - 1, i);
for (j = 0; j < 7; j++){
if(0==H[i][j])continue;
sum += H[i][j] * tau1 * ipow(del - 1, j);
}
}
return exp(del * sum);
}
double freesteam_mu_rhoT(double rho, double T){
double del = rho / IAPWS97_RHOCRIT;
double tau = IAPWS97_TCRIT / T;
const int mu2 = 1;
/* critical enhancement to viscosity not implemented for IF-97, set to 1 */
return VISCOSITY_MUSTAR * mu0(tau) * mu1(del,tau) * mu2;
}
|
