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Miko June 19, 2003 03:28

Problem on boundary conditions
 
Hi all! I have trouble when I define inlet/outlet. I'm confused by how to set pressure. If I want to set the static pressure of Point A (inlet) 50 Pa greater than that of Point B (outlet) and the initial velocity of inlet is zero, how can I put it into practise? Is it right that I specify Mass and Momentum of inlet as Static Pressure with 50 Pa and outlet 0 Pa?

Best regards!

Miko

Neale June 20, 2003 01:11

Re: Problem on boundary conditions
 
While this physically makes sense it does not constrain momentum and you may have a lot of difficulty getting a solution as a result. i.e. any momentum flow will give you the solution you want.

I suggest that you run total pressure inlet and mass flow outlet or static pressure outlet until you get the inlet velocity you want.

Neale

Miko June 20, 2003 08:22

Re: Problem on boundary conditions
 
Hi Neale!

Thank you for your guideline! But I still have problem to understand what you have said.

1. Why does my setting make sense but be unable to get a satisfied solution? Since I have a little idea on CFX modeling, I hope you can give me some explanation in point.

2. According to your suggest, what's the specfic value I should specify, such as total pressure inlet, mass flow outlet or static pressure outlet?

Thank you for your time!

Miko


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