Learning Forum

[Dato]

Hi,

I have created a rake with 500 number of points whose length is 0.02mm. It's near the wall because I want as many as data near the wall though there may be 2~3 boundary layer growing from the wall.  

But when I check the xy plot on it, it turns out to be not so many scatter in the graphic. 

I wonder if Fluent cannot interpolate enough data point in such tiny length? Or I have to go to cfd-post to deal with it? But I think getting row data in Fluent is much more convient and accurate.

Any suggestions would be greatly appreciated.

[Rob]

How many cells are there in the near wall region? Did you resolve the mesh to 0.04 microns? 

[Dato]

The rake starts from the surface of the wall and extends perpendicular to the direction of fluid flow.  I created the mesh in FluentMeshign and the first boundary layer height is 0.0045mm and the number of layers is 4. I used Last Ratio method. There may be two layer cells in the region. 

I got that means. But I have tried to do the same thing in cfd-post and I can get as many data as I want in such short length though there are not so many mesh resolved on the line. Could you give some explanations?

regards.

[Rob]

CFD Post uses a different method, and also will interpolate the Fluent data to the nodes from the cell centres. Given the scale and mesh resolution that may mean you see slightly different results.