I am simulating a micro structure case where my characteristic length and velocity are 7e-06 meters and 1e-06 m/s respectively. I am running a simulation where I have inlet and outlet velocity boundary of 1e-06 m/s in negative z direction.Along with that I have two moving walls of 1e-06 m/s and symmetry boundary conditions in x and y direction The fluid used here is air at 25 Celsius and 1atm pressure. My main aim is to find the pressure forces on the inlet and outlet surfaces. When I run the simulation I get a stable Average energy and Umax per time step, the value becomes constant after some timesteps. However, my pressure values are constantly increasing and it does not converge to a value.
I tried setting my Tau to 0.99 as one get stable solution around unity , but I still dont get stable pressure values. If I set a very small time step i.e tau around 0.5, my simulation gets diverged.I also tried increasing the resolution of the model, still no luck.
Could you please help me with this problem?