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 Neil October 23, 2006 09:58

Reynold's number and incompressible flow

Dear all,

I am a beginner at modelling incompressible flow conditions. I have read some papers which model incompressible internal flow and they mention that they are restricted to low Reynold's number for stability reasons. Does solving high Re number flows present a particular difficulty when solving the incompressible flow equations? How are stability problems resolved? by using a finer mesh?

Thanks

Neil

 Mani October 23, 2006 16:25

Re: Reynold's number and incompressible flow

I guess the answer to your question depends on clarification of some points you brush over:

a) Who are "they", in your sentence "they are restricted to low Reynold's number"? The flows, the algorithms, ... (if I read your sentence literally, the papers mention that the papers are restricted... which would be very bad behavior for a paper)

b) Related to question a), what type of stability are we talking about: Flow stability, numerical stability...

c) What Reynolds number are we talking about, i.e. how is it defined. Is it the cell Reynolds number (Peclet number)?

A clear question has the best chance to prompt a clear answer. Lucky for you, this forum is not an oracle which gives you only one shot. :) Try again.

 Neil October 24, 2006 02:56

Re: Reynold's number and incompressible flow

Sorry for not making my question clearer

a) It is the algorithm that is restricted to low Reynold's numbers

b) numerical instability

c) Reynold's number is defined based on the diameter of the flow channel