[jeremyding]

Hello everyone:
I am trying to numerically simulate the electric field strength using an extended commercial computational fluid dynamics(CFD) code. The generic method used for the simulation of particle phase in the FLUENT code is the discrete phase model(DPM). In the process of implanting a body force, I really need help and guide,
The electric force on a charged particle can be given by

F=qE+q*q/16*a* *


The second term is the image force and a is the spacing between the particle and the target. I wonder how is the letter a complied in the FLUENT code ? How is the second force unitied with the first force? How are the two kinds of forces kept consistent in director?