[minox101]

Hello.

I am trying to simulate air underneath different head pressures. I have designed a box where I can vary pressure by changing the initial pressure. But I want to specify the pressure at the air velocity pressure as atmospheric pressure is there any way I can do this ?

[bluebase]

Originally Posted by minox101

Hello.
But I want to specify the pressure at the air velocity pressure as atmospheric pressure is there any way I can do this ?

Hi Andrew, could you rephrase your question please?

It's not explicit what you want to do. You have a box. Are there any inlets/outlets? If there are such boundaries, you have the options to make them stagnation inlet/outlets where you set the total pressure. The velocity magnitude "evolves" during the simulations.

Regarding atmospheric pressure, StarCCM has a constant offset for pressure (likely to reduce rounding errors). This constant is typically set to one atmosphere. So in the default case, 0 Pa (relative Pressure) actually means an absolute pressure of 1013 hPa.
If you would now set an inlet boundary to 1bar, it would actually be 2bar absolute pressure.

If you have a box without any flow inlets/outlets, then you might need to give more detail on your question, because i can't interpret it in this context.


Best regards,
Sebastian