interaction time between particle and eddies

Steve

I like to modify the interaction time between particle and eddy in Lagrangian particle tracking. The time interaction is only determined by the eddy life time, Te in Fluent 4.5 When you have a slip velocity, the time interaction between the eddy and particle will be reduced. If Le = eddy length scale, the time needed by the particle to travel one eddy is Tr = |Le/(Ug-Us)| The correct time interaction will be MIN (Te,Tr) Is there any way to modify the interaction time in user subroutine