Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

pressure result and boundary setting problem

Please login with a confirmed email address before reporting spam

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 2012年2月22日 GMT-5 01:44
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2012年2月22日 GMT-5 01:44
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

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.