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 maxims September 26, 2010 05:01

boundary condition problem

1 Attachment(s)
Boundary conditions:
See the following resonator figure, all the pipe walls are set as non-slip and isothermal. A static pressure oscillation at the left side of this pipe is known as p(t).

Question:
How can I deal with the boundary condition for the left side of this pipe in my code? It seems like inflow boundary, but also like outflow boundary, because this left side is the only contact interface with outside air. The only boundary condition I know is the static pressure history p(t), the velocity condition is unknown. Any suggestion is welcome.

 liwei@imech.ac.cn September 26, 2010 22:05

I tried this problem in Fluent, but the boundary conditions it needs are total pressure and temperature.
I don't know what will happen if the static pressure is specified at the left side in a UDF code.

 liwei@imech.ac.cn September 26, 2010 22:12

the key problem is how to give a relatively exact estimation of velocities at the left side and how to correct this estimation to the real velocities with the known static pressure of left boundary

 pallavkant September 29, 2010 14:43

hey maxims,

I guess the boundary condition of outflow will suit this kind of problem very best.

 maxims October 10, 2010 21:34

Hi, pallavkant, thanks for your reply. If outflow is good, I don't know how to set up the inlet boundary condition, for I only know the pressure condition of the interface.

Quote:
 Originally Posted by pallavkant (Post 277164) hey maxims, I guess the boundary condition of outflow will suit this kind of problem very best.

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