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pressure result and boundary setting problem

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Hi, I am working on fluid flow problem and would like to ask:

1. In result part (fluid flow physic), the pressure shown is indicated to total pressure or static pressure?

2. Can I set pressure point constraint at the inlet while having inlet velocity as boundary condition? I am asking because my model don't have outlet and I think I should have pressure somewhere to solve fluid equation.

Thanks a lot!

1 Reply Last Post 22 févr. 2012, 01:44 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 22 févr. 2012, 01:44 UTC−5
Hi

as you solve also for p, you need definitively some way of fixing p in your model, but it's not necesarily at the inlet, even I would avoid that, as often the inlet conditions adapts p to respect v.

normally p is the gauge pressure, and you need to add "pa" the absolute pressure (used for material property extraction) but that depends somewhat how you have defined your model entity values.

the best is to recheck the underlaying equation in the equation view, in case of doubts

--
Good luck
Ivar
Hi as you solve also for p, you need definitively some way of fixing p in your model, but it's not necesarily at the inlet, even I would avoid that, as often the inlet conditions adapts p to respect v. normally p is the gauge pressure, and you need to add "pa" the absolute pressure (used for material property extraction) but that depends somewhat how you have defined your model entity values. the best is to recheck the underlaying equation in the equation view, in case of doubts -- Good luck Ivar

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