Pressure inlet boundary condition

vikingd · February 20, 2020, 09:31

Hello,
I want to translate the pressure-inlet boundary condition that I am using on Fluent to another CFD solver. I have the following options
The Dirichlet boundary condition.
Neumann boundary condition.
Which would be most suitable in this case?

Any help will be appreciated.

Thanks

LuckyTran · February 20, 2020, 11:29

Applying a pressure value on a boundary is a Dirichlet type in pressure. But make sure this is a Dirichlet for pressure (and not velocity).

Dirichlet means you fix the value. Neumann means you fix the gradient.

vinerm · February 20, 2020, 11:53

As mentioned, it is Dirichlet. However, there is no conservation equation for pressure, hence, pressure value is not directly applied at the boundary. It is used to determine a velocity and that is applied. Pressure value is used only as a reference to adjust the pressure-field in the rest of the domain.

February 20, 2020, 09:31	Pressure inlet boundary condition	#1
vikingd New Member Viking Join Date: Nov 2019 Posts: 4 Rep Power: 6	Hello, I want to translate the pressure-inlet boundary condition that I am using on Fluent to another CFD solver. I have the following options The Dirichlet boundary condition. Neumann boundary condition. Which would be most suitable in this case? Any help will be appreciated. Thanks Last edited by vikingd; February 20, 2020 at 10:38.

February 20, 2020, 11:53	Pressure Condition	#3
vinerm Senior Member Vinerm Join Date: Jun 2009 Location: Nederland Posts: 2,946 Blog Entries: 1 Rep Power: 35	As mentioned, it is Dirichlet. However, there is no conservation equation for pressure, hence, pressure value is not directly applied at the boundary. It is used to determine a velocity and that is applied. Pressure value is used only as a reference to adjust the pressure-field in the rest of the domain. __________________ Regards, Vinerm PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority.

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February 20, 2020, 11:29		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,675 Rep Power: 66	Applying a pressure value on a boundary is a Dirichlet type in pressure. But make sure this is a Dirichlet for pressure (and not velocity). Dirichlet means you fix the value. Neumann means you fix the gradient.