allways problems with ideal gas

March 31, 2006, 07:14

Hi!

I am simulating turbulent gas flow at high temp (400 - 1000 K) and high pressure (10 - 20 bar). When I turn on ideal gas law, I have allway problems with the floating point error.

The same sim. with incomp. ideal gas is working very well.

What are the best settings for ideal gas?? what solver is the best (i am using seg.)? What is the best vel-pressure couling sheme? are there other factors (urf,...)???

Any help is highly appreciated!!

Ralf

March 31, 2006, 11:35

Never use ideal-gas law unless u really need it. If u really need it decrease the density urf (0,2-0,5) the pressure URF (0.05-0.2) and the momentum URF (0.4-0.6). For the p-v coupling start with the SIMPLE.

Thomas

March 31, 2006, 07:14	allways problems with ideal gas	#1
Ralf Schmidt Guest Posts: n/a	Hi! I am simulating turbulent gas flow at high temp (400 - 1000 K) and high pressure (10 - 20 bar). When I turn on ideal gas law, I have allway problems with the floating point error. The same sim. with incomp. ideal gas is working very well. What are the best settings for ideal gas?? what solver is the best (i am using seg.)? What is the best vel-pressure couling sheme? are there other factors (urf,...)??? Any help is highly appreciated!! Ralf

March 31, 2006, 11:35	Re: allways problems with ideal gas	#2
Thomas Guest Posts: n/a	Never use ideal-gas law unless u really need it. If u really need it decrease the density urf (0,2-0,5) the pressure URF (0.05-0.2) and the momentum URF (0.4-0.6). For the p-v coupling start with the SIMPLE. Thomas

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