turbulent mixing of two fluids
hi there
i want to model the mixing of two fluids in a tube bend. the fluids have the same density but very different molecular viscosities. the flow is turbulent (Re about 5000). in fact, i want to solve the problem by using a two fluid model, i.e. i will use two momentum equtions, one mass transport equation and one continuity equation. however, i think that a turbulent viscosity which is calculated independently for each fluid will not lead to correct results. i would be glad is someone who has already modeled this problem can give me some advise how to model physically corret the mixing of two fluids. thanks in advance ulrich 
Re: turbulent mixing of two fluids
You are working in a complex area. No wonder you are kind of lost! Let me give you some references for you
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Re: turbulent mixing of two fluids
(1). In the mixing zone, the turbulent Reynolds number will be of O(100) or less. (2). So, I don't think the difference in the molecular viscosity between two fluid is important in the mixing process.

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