UDF for SOURCE
 

hi all,

1. When adding a source/sink through, we have to give input as generation rate/volume. But is it necessary to divide the source term by volume[C_V(cell)] or Fluent will do it?

2. For Multiphase flow..

Is there any difference in the values of

C_P(cell,mix_th) and C_P(cell,pri_th)?

3. Same for C_T(cell,mix_th) and C_T(cell,pri_th)?

Thanks.

Mahesh

Re: UDF for SOURCE
 

Hi Mahesh,

1. When you write a source term you must refer it to the unit volume (1 m^3), not to the cell volume. Check units of your source.

2. Supposing that mix_th is the thread of the mixture and pri_th is the thread of the primary phase,

C_T(cell,mix_th)

refers to the cell value of the temperature of the mixture, while

C_T(cell,pri_th)

refers to the temperature of the primary phase. Their values are equal only if phases reached thermic equilibrium.

Same for pressure, even if this may depend on the model you use. For example, if you use the Eulerian model, the pressure is considered the same for all phases.