Re: Time-Dependent Natural Convection in a Square Cavity
This post was updated on .
Thank for reporting the issue. Fluid flow problems without outflows, like your example, require the pressure to be unique (to converge). In order to do this an integral constraint setting the mean pressure to zero is introduced per default. This modifies the system matrix which seems to conflict with the time dependent solver (this will be addressed in a future update).
Alternatively, you can remove the integral constraint (clear "Equation" menu > "Subdomain Integral Constraints..." > p), and instead fix the pressure in one point ("Boundary" menu > "Point Constraints..." > p), this should work for all time stepping schemes.
EDIT: Update 1.15.4 is now available with a fix supporting integral constraints and time-stepping schemes.