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Phia April 16, 2010 07:03

modelling: high- and low re grids
Hi everyone,
I'm a student from Germany (so I'm sorry for my english and my frustratingly poor cfd-knowledge..) and I need some help concerning turbulent flow modelling:

We made a model (stepflow) using k-omega / k-epsilon methods and high-re/low-re grids.
As far as I know low-Re grids are for laminar boundary layers, where you are able to calculate the shape of the boundary layer and thats why you need a grid with small steps. Right?
When you have a turbulent boundary layer you need an approximation for calculating the shape, such as the 1/7-"wandgesetz". You don't need such small steps because you use the Approximation and know the shape without calculating at several points. Am I right?

Now, my question: what about the buffer layer, where you don't know whether the layer ist turbulent or not? Do you use a low-re grid and try to calculate it? But if its turbulent, how does that work? (we use FresCo)

I hope you can help me, I'm a bit confused...:confused:

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