Learning Forum

[Prashant Jha]

Hello all

I am trying to simulate natural convection in a rectangular 2d domain using VOF where 3 phases are there. At the bottom, wax(primary phase) is there, above it water(secondary phase) and on top air(secondary phase). The bottom wall is heated by a heat flux and rest 3 walls are at room temperature. I have marked the 3 phases using cell register option but don't know how to patch them?

[Rob]

Once you've initialised the domain use "Patch" and pick the cell zone(s) of interest. Note, you may need to patch other phases to zero before patching the desired phase to one: it's a numerical check somewhere to stop you having a total volume fraction over one that can glitch. 

[Prashant Jha]

Thanks for your reply. If I am not wrong, what I have understood is that, I need to patch water with its corresponding cell zones to one and with other cell zones to 0. Similarly, for air, patching has to be done.

[Rob]

Yes, it's generally a good idea to use Standard initialisation, with all of one phase and then patch the other two in. Check the phases are correctly defined (and save case & data) before pressing the iterate button.