Regions & cells
 

Dear users,

I am unable to understand the significance of different number of regions in different directions and then diff no. of cells in diff regions.
Please explain if anyone knows, also how their no. affects the solution...

Guaravg,

The regions are created in most cases automatically by phoenics at the edges of an object. They allow to change the size of the mesh in that region. hence, if you have a region around your area of interest (say a building in the middle of your domain) you can reduce the size of the mesh in this area while keeping it bigger in the other areas, hence saving mesh and computational time. Beware though, you should ensure that the size difference of cells between one region and another must be similar. So if you are using a fine mesh in one region, use the power/ratio box to gradually make your mesh bigger in the outer region.

Hope that helps