Conflict between des_interp_scheme and energy equation

MFiX
#1

Hi, everyone!
Recently, I just would like to simulate particles heat transfer with fluid. However, the interp_scheme did not support the energy equation as we all know. Does anyone has the experience of this, cause the interpolation scheme only cares about the velocity which relates to the drag force, but I do not understand why it does not support the energy equation. Do you know is it because of the codes that are under development or something with the theory side?

#2

Neither DEM nor PIC use interpolation for energy to remain as consistent as possible with chemical reactions which can also contribute source terms to the energy equation.

To elaborate on that a bit, the solver assumes that the local field quantities used to calculate reaction rates for particles are not interpolated. This is because the solver only provides the index of the fluid cell (IJK) containing a particle. It would be on a user to correctly interpolate needed field quantities (e.g., gas temperature, mixture molecular weight, species mass fractions, etc.) to a particle’s position prior to calculating its reaction rates. Furthermore, the interpolation the user employed would have to be consistent with how the solver later deposits interphase mass and energy back to the Eulerian grid.

Ensuring that deposition to and interpolation from the Eulerian grid isn’t necessarily a complicated task but there are many subtleties that are easy to get wrong. Therefore, it was decided that energy/mass interpolation would not be supported.

#3

Thanks for your kind reply!
I think I have understood the reason. However, do you think it’s reliable if I just ignore the interpolation of the energy? What I mean is that interpolating the volume fraction and velocity using GARG_2012 without considering the other parameters’ interpolation instead of interpolating nothing when open the energy equation (no reaction).

#4

Hi,
I was trying to implement massless tracer “particles” to record the the fluid movement, in which there may be 10 particles in one cell.
Thus, I need to interpolate the fluid velcoity within a fluid cell.

I am reading the DRAG_INTERPOLATION in drag_gs_des0.f. However, the variable name are quiet simple. Is there any documents explaining the Interpolation of fluid velocity at certain particel position？

Kind regards
Yuanhe