CFD Online Discussion Forums

CFD Online Discussion Forums (
-   OpenFOAM (
-   -   recommended cell expansion ratio (

guy_smiling October 6, 2010 15:24

recommended cell expansion ratio
Hi all,

I remember reading somewhere that the recommended cell expansion ratio was between 0.833 and 1.2 from adjacent cells, but I can't seem to find that reference anywhere now. Does anyone know if there is a recommended cell expansion ratio and if there's a good reason for it?


LarsPT October 12, 2010 13:15

Maybe I found something. If I use high expansion rates, i.e. high cell aspect ratios and run checkMesh -allGeometry -allTopology, I will get an error message because of small determinant of some cells. A cell determinant of 1 relates to a hexahedral cell whereas a small value relates to an illegal flattened cell. As far is I had a look at this problem the error occurs when the cell determinant is smaller than 1e-03. So one can maybe conclude to a maximal aspect ratio?


All times are GMT -4. The time now is 20:34.