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A.M.Yang January 22, 2002 04:42

Low Reynolds Number Flow Computation
 
Hi,

What are the difficulties in the computation of low Reynolds number viscous flow?

Thank you in advance.

Andrey January 22, 2002 05:13

Re: Low Reynolds Number Flow Computation
 
Low Reynolds number viscous flow - no problem! It's very simple!

Alexey January 22, 2002 05:42

Re: Low Reynolds Number Flow Computation
 
It depends on Mach number. If M is not small (for example > 1) this problem is not "very simple!"

Alexey

Andrey January 22, 2002 07:35

Re: Low Reynolds Number Flow Computation
 
If Mach number too big -> Reynolds number not small!

Farshid January 22, 2002 09:55

Re: Low Reynolds Number Flow Computation
 
If the scale of your simulation is of the order of hundreds of micro meters or less, you might have some problems with boundary conditions. For instance, no slip b.c.'s may not be valid. Especially, this problem arises when Mach number is large.

Christian Holm January 22, 2002 10:28

Re: Low Reynolds Number Flow Computation
 
Does that not depent on weather the assumption of the fluid being a continuum holds ? ie. if we have a thin low pressure gas and small dimensions, then the eq. we normally use are not valid.

Christian

mukkarum hussain January 22, 2002 12:16

Re: Low Reynolds Number Flow Computation
 
plz send me books on this topic and on cfd thanks

mukkarum

new one in cfd

Alexey January 22, 2002 13:01

Re: Low Reynolds Number Flow Computation
 
Situation when Re is small and M is big may take place when gas is strongly rarefied. In this case either Navier-Stokes or Boltzmann equations are used depending on Knudsen number.

=Alexey



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