Learning Forum

[z5489721]

I am calculating the particle reaction rate and using C_UDMI to get a contour plot of it. but I am just making C_UDMI equal to reaction rate *rr. Is it correct? or do I need to loop like this: if yes, which define macro do I need to use, or can I loop it inside DEFINE_PR_RATE? why am I using um? because in udf I am calculating *rr in kg/s, but in contour plot unit is different kmol/m3 s

thread_loop_c (t,domain)
{
begin_c_loop (c,t)
{
C_UDMI(c,t,0) = *rr;
}
end_c_loop (c,t)
}

[Rob]

You also need to be careful as you need to account for multiple parcels in a cell. 

[z5489721]

Can you explain more? I didn't get it. Do I need to use a loop and inside loop I need to consider the following C_UDMI(c, t, 0) += *rr?

[Rob]

You may have many particles in a cell. Do you want the sum of all reaction rates, the average or something else? As the particle reaction rate is tracked on the particles which then interact with the cells, what does the UDM do?