求助 蒸发沸腾的UDF问题

daxiongmonv

各位大侠，我的计算背景是贮存有部分液氢和氢气的贮箱，初始处于饱和状态下，分析存在壁面传热的情况下贮箱内压力上升情况和流体温度分层情况，现在两相间的传热传值模采用fluent公司提供的boiling UDF的例子，进行了物性参数的改动，同时饱和温度取对应贮箱压力，而不是一个定值。现在编译没问题，计算后结果竟然导致压力和温度下降，不知道问题出在哪，请高手指点，万分感谢！UDF代码如下
#include <stdio.h>
#include <math.h>
#include "udf.h"
#include "sg_mphase.h"
#define L 445600
#define TB  20.268
#define PB  101325
#define R  4157
#define b 0.1

DEFINE_SOURCE(liq_src, cell, pri_th, dS, eqn)
{
Thread *mix_th, *sec_th;
real m_dot_l,Psat,T_SAT;
mix_th = THREAD_SUPER_THREAD(pri_th);
sec_th = THREAD_SUB_THREAD(mix_th, 1);
Psat = C_P(cell,pri_th);
T_SAT=1/(1/TB-R*log(Psat/PB)/L);

if(C_T(cell, mix_th)>=T_SAT){
m_dot_l = -b*C_VOF(cell, pri_th)*C_R(cell, pri_th)*
fabs(C_T(cell, pri_th) - T_SAT)/T_SAT;
dS[eqn] = -b*C_R(cell, pri_th)*
fabs(C_T(cell, pri_th) - T_SAT)/T_SAT;
}
else {
m_dot_l = b*C_VOF(cell, sec_th)*C_R(cell, sec_th)*
fabs(T_SAT-C_T(cell,mix_th))/T_SAT;
dS[eqn] = 0.;
}
return m_dot_l;
}
DEFINE_SOURCE(vap_src, cell, sec_th, dS, eqn)
{
Thread * mix_th, *pri_th;
real m_dot_v,Psat,T_SAT;
mix_th = THREAD_SUPER_THREAD(sec_th);
pri_th = THREAD_SUB_THREAD(mix_th, 0);
Psat = C_P(cell,pri_th);
T_SAT=1/(1/TB-R*log(Psat/PB)/L);
if(C_T(cell, mix_th)>=T_SAT){
m_dot_v = b*C_VOF(cell, pri_th)*C_R(cell, pri_th)*
fabs(C_T(cell, mix_th) - T_SAT)/T_SAT;
dS[eqn] = 0.;
}
else {
m_dot_v = -b*C_VOF(cell, sec_th)*C_R(cell, sec_th)*
fabs(T_SAT-C_T(cell,mix_th))/T_SAT;
dS[eqn] = -b*C_R(cell, sec_th)*
fabs(C_T(cell, sec_th) - T_SAT)/T_SAT;
}
return m_dot_v;

}
DEFINE_SOURCE(enrg_src, cell, mix_th, dS, eqn)
{
Thread *pri_th, *sec_th;
real m_dot,Psat,T_SAT;
pri_th = THREAD_SUB_THREAD(mix_th, 0);
sec_th = THREAD_SUB_THREAD(mix_th, 1);
Psat = C_P(cell,pri_th);
T_SAT=1/(1/TB-R*log(Psat/PB)/L);

if(C_T(cell, mix_th)>=T_SAT){
m_dot = -b*C_VOF(cell, pri_th)*C_R(cell, pri_th)*
fabs(C_T(cell, pri_th) - T_SAT)/T_SAT;
dS[eqn] = -b*C_VOF(cell, pri_th)*C_R(cell, pri_th)/T_SAT;
}

else {
m_dot = b*C_VOF(cell, sec_th)*C_R(cell, sec_th)*
fabs(T_SAT-C_T(cell,mix_th))/T_SAT;
dS[eqn] = -b*C_VOF(cell, sec_th)*C_R(cell, sec_th)/T_SAT;}
return L*m_dot;
}

buctzy

我做的东西跟楼主很相似，想问一下，我用这个UDF程序总是提示Floating error怎么办？

小七工作室

计算时间步长比较大容易出错误