Hello Rwoolu,

Thank you for replying me. Can I ask how would the "mesh requirement" be based upon if the particles are treated as point mass? Is there any documentation about this dependency? Does the dependency come from the model or the algorithm of cfx developers itself? Because the idea of point mass treatment does not explain the minimum mesh size dependency, I am pretty confused on this problem. If I do not have a good refinement, then I would not be solve the wall functions in flow analysis. This would not give me right variables needed for Lagrangian tracking. Do I have to weigh in the mesh size and particle diameter to perform simulations then?

Hello Raef, Do you mean the minimum mesh size or the number of elements? The minimum mesh size in X,Y, Z dimension is 0.0129 [dimensionless], 0.06079 [dimensionless] and 0 [dimensionless] in ICEM. The geometry is in metres. The total elements is around 1 million.