outflow boudary condition

July 8, 2003, 06:59

hello,

Why is the outflow boudary condition inappropriate for compressible flow ? In my problem, this condition seems good but the fluid is compressible. Could you help me?

Thanks

July 8, 2003, 23:35

If you want to use outflow BC, you must sure that flow is really out of your domain that means no reverse flow happened.

July 15, 2003, 00:13

If I am sure of no reverse flow but at the exit flow is supersonic compressible, is it a right choice in this situation, if no then anyother suggestion, thanks

July 18, 2003, 14:00

No, you can only use pressure outlet for compressible flow simulations.

July 23, 2003, 04:55

In external flow problems like flow over an aerfoil or on a cone usually before hand one is not known of pressure or velocity at the outlets, then how to use that pressure condition (for the case when I want to take outlet condition exactly at the body end)

July 8, 2003, 06:59	outflow boudary condition	#1
damien Guest Posts: n/a	hello, Why is the outflow boudary condition inappropriate for compressible flow ? In my problem, this condition seems good but the fluid is compressible. Could you help me? Thanks

July 8, 2003, 23:35	Re: outflow boudary condition	#2
Neo Guest Posts: n/a	If you want to use outflow BC, you must sure that flow is really out of your domain that means no reverse flow happened.

July 15, 2003, 00:13	Re: outflow boudary condition	#3
asif Guest Posts: n/a	If I am sure of no reverse flow but at the exit flow is supersonic compressible, is it a right choice in this situation, if no then anyother suggestion, thanks

July 18, 2003, 14:00	Re: outflow boudary condition	#4
KT Guest Posts: n/a	No, you can only use pressure outlet for compressible flow simulations.

July 23, 2003, 04:55	Re: outflow boudary condition	#5
asif Guest Posts: n/a	In external flow problems like flow over an aerfoil or on a cone usually before hand one is not known of pressure or velocity at the outlets, then how to use that pressure condition (for the case when I want to take outlet condition exactly at the body end)

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