[leizhao512]

Hi, everyone, I am now simulating a reacting flow and need to write my own reaction models(DEFINE_VR_RATE). This is my first time to write UDF and I was kinda struggled. The followed is my UDF:
DEFINE_VR_RATE(Reaction_Rate, c, t, r, mw, yi, rate, rr_t)
{
real qac, kac, kox, x, sac, sm;
qac = 10.0;
kac = 0.001;
kox = 0.0001;
sac = C_R(c, t)*yi[r->reactant[0]] / mw[r->reactant[0]];
x = C_R(c, t)*yi[r->product[1]] / mw[r->product[1]];
sm = C_R(c, t)*yi[r->reactant[1]] / mw[r->reactant[0]];
*rate = qac*x*sac / (kac + sac)*sm / (kox + sm);
*rr_t = *rate;
}

However, when I tried to interpret this UDF, Fluent reported "structure reference not implemented" at "sac = C_R(c, t)*yi[r->reactant[0]] / mw[r->reactant[0]];"

Can anyone explain the variable of "yi" to me? Or is there any resource that talks about the variable structures in Fluent?

[leizhao512]

I also tried to use the muti-reactions statement from the UDF tutorial:
"if (!strcmp(r->name, "reaction-1"))"
Fluent also reports "Structure reference not implemented"

[`e`]

The UDF manual explains the arguments for each macro; specifically, yi is the pointer to array of the species mass fractions.

You will probably need to compile this UDF instead of interpreting.

[leizhao512]

Originally Posted by `e`

The UDF manual explains the arguments for each macro; specifically, yi is the pointer to array of the species mass fractions.

You will probably need to compile this UDF instead of interpreting.

Thank you, I tried to compile the UDF. However, it said "nmake is not recognized as an internal or external command". I followed the instruction on http://www.cfd-online.com/Wiki/Fluen...ows_7_64bit.3F. It worked on one of my computers. However, when I did the same thing to my new computer, it gave me another weird error:"fatal error C1083: Cannot open include file: 'basetsd.h': No such file or directory"

Can you help me fix this?

[`e`]

Sounds like you're having troubles with a Windows compiler. I recommend installing Microsoft Visual Studio Express for Windows and ensure it's compatible with your Fluent version.

[renika14]

Dear all

I am facing the same problem while working with multiple reactions. Has someone solve the problem??