How much do I numerical dissipation?
 

I'm studying a kind of particle method in which viscosity can be controled quantificationally. I'm trying to solve shockwave case with it. Because of the dicontinuity, some numerical disipation is needed. I tried to add an additional viscosity term. But I don't know how to define the viscosity coeeficient of the numerical disipation.

Re: How much do I numerical dissipation?
 

which scheme r u using

Re: How much do I numerical dissipation?
 

The scheme is not of FDM/FVM/FEM. It is a kind of lattice boltzmann scheme in which viscosity can be controlled by a parameter Tao. At every node, the viscosity nu is a function of pressure P and collision time Tao. If the viscosity is known, I can get Tao according to P. Now I don't know how to estimate the best viscosity nu. If nu is too small, Tao will be too small and the solver will diverge. If it is too large, Tao will be too large and the result will be absurd.