hello to everybody! I would like to ask you a simple question. How i can define fixed values in a small domain within a particular fluid zone (in the rest zone i want the solver to solve the Navier-Stokes properly) , without creating a new fluid zone. I tried with udf's but wasn't suceed. Why is it necessary to define new fluid zone??? thanks

Go to -Adapt-Region, marked the region you want to define as fixed. Then go to Grid-separate-cells, here you can separate the two regions. Then when defining boundary conditions you can define the new fluid region as fixed values. Hope this can help.

thanks Zhihua! but i do not want to create a new fluid region, but in the same fluid zone i want to fix the values in a subdomain.In the rest of the zone i don't want to have fixed values.suppose that you have a zone x 0 to 200 and y 0 to 100, i want to have fixed values to the subdomain x 0 30 and y 20 50, without a new zone. i tried to separate cells by region but it is not activated, i can only by marking (at the seperate cells panel). thanks for your try! best regards