Convergence problem when use gravity

aroma · February 18, 2013, 05:31

Hi pals,

I have a model with gravity and the boundaries should have constant static pressure (not considering the gravity body force). I am trying to model a flow field with specific static pressure boundary faces and gravity. existance of gravity (as a body force) should affect the flow.

I tried both "Stagnation Inlet" and "Pressure Outlet" and I used field function below for boundary condition as total pressure.

(I should say, I used the correct syntax, I am just explaining the concept here)
"static pressure inlet"+ 0.5*Density*V^2 + Density * gravity * distance
or

"static pressure outlet"+ 0.5*Density*V^2 - Density * gravity * distance

in all cases that I have the "gravity" term, my simulation is not getting converge.

I really do not know what else should I try.
I aapreciate it if anybody can help.

Hamed

RodriguezFatz · April 10, 2013, 11:18

Hi Aroma,
Please post a picture of your domain with some explanations. I have a quite similar problem (in Fluent)...

February 18, 2013, 05:31	Convergence problem when use gravity	#1
aroma New Member Hamed Join Date: Jul 2012 Posts: 16 Rep Power: 14	Hi pals, I have a model with gravity and the boundaries should have constant static pressure (not considering the gravity body force). I am trying to model a flow field with specific static pressure boundary faces and gravity. existance of gravity (as a body force) should affect the flow. I tried both "Stagnation Inlet" and "Pressure Outlet" and I used field function below for boundary condition as total pressure. (I should say, I used the correct syntax, I am just explaining the concept here) "static pressure inlet"+ 0.5DensityV^2 + Density * gravity * distance or "static pressure outlet"+ 0.5DensityV^2 - Density * gravity * distance in all cases that I have the "gravity" term, my simulation is not getting converge. I really do not know what else should I try. I aapreciate it if anybody can help. Hamed

April 10, 2013, 11:18		#2
RodriguezFatz Senior Member Philipp Join Date: Jun 2011 Location: Germany Posts: 1,297 Rep Power: 27	Hi Aroma, Please post a picture of your domain with some explanations. I have a quite similar problem (in Fluent)... __________________ The skeleton ran out of shampoo in the shower.

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