[yf70512]

Hello everyone,

I am trying to modify the source term of energy equation in non-equilibrium thermal model by UDS and UDF (DEFINE_SOURCE macro).
But the Fluent crashed when the code runned with the error "999999:mpt_accept:error: accept failed: No error". My code is as following:

DEFINE_SOURCE(Fluid_source,c,t,dS,eqn)
{

real Tf, Ts;
real hfs = HFS_CONSTANT; // Placeholder value for heat transfer coefficient
real Afs = AFS_CONSTANT; // Placeholder value for interfacial area density
real source;

// Obtain fluid and solid temperatures
Tf = C_T(c, t); // Fluid temperature
Ts = C_STORAGE_R(c, t, SV_T_S); // Solid temperature

// Calculate the source term based on the modified expression
source = hfs * Afs * (pow(Ts, 4.0) - pow(Tf, 4.0));

// Set the derivative of the source term with respect to Tf
dS[eqn] = 4.0 * hfs * Afs * pow(Ts, 3.0) - 4.0 * hfs * Afs * pow(Tf, 3.0);

return source;

}


DEFINE_SOURCE(Solid_source,c,t,dS,eqn)
{

real Tf, Ts;
real hfs = HFS_CONSTANT; // Placeholder value for heat transfer coefficient
real Afs = AFS_CONSTANT; // Placeholder value for interfacial area density
real source;

// Obtain fluid and solid temperatures
Ts = C_STORAGE_R(c, t, SV_T_S); // Solid temperature
Tf = C_T(c, t); // Fluid temperature

// Calculate the source term based on the modified expression
source = hfs * Afs * (pow(Tf, 4.0) - pow(Ts, 4.0));

// Set the derivative of the source term with respect to Tf
dS[eqn] = 4.0 * hfs * Afs * pow(Tf, 3.0) - 4.0 * hfs * Afs * pow(Ts, 3.0);

return source;

}

I am not sure if it was caused by the wrong expreesion of reading the solid temperature. Could someone please give me some suggestions? Many thanks.

Best regards,

Fan