Hi, I have a number of issues with using passive scalars in Star-ccm+.

1. Only one passive scalar can be used per simulation 2. If one needs to solve for a new passive scalar (once a flow field solution is obtained) with a different initial condition, the total solution needs to be cleared, i.e. it is not possible to simply wipe away the solution of the previous passive scalar.

The above points are very frustrating, mainly because in my simulations I have an 3D unsteady solution and I want to solve 3 passive scalars. This takes so much time. Is there any news on whether the option of including multiple scalars will be included in the software?

Couldn't you just create 3 (or 4 if you want a background fluid) active scalars all with the same physical properties but different names ?

You should then be able track the various flows around the place.