CFD Online Discussion Forums - some questions in SnappyHexMesh

Hi everyone,

I got some questions would like to ask you,

The first one, in snappyHexMesh tutorial (in OPENFOAM user guide), there are more cells around the car surface, which part in snappyhexDict is to achieve this?

Secondly, what does the "level" mean? for example,
refinementSurfaces
sphere.stl
{
level (2 2)
...
what are the real meaning of the numbers in the ()? any detailed explanation?

Finally, normally we need a blockMesh as a blackground mesh for snappyHex, for my cylinder case, if the blockMesh size is larger than the cylinder , the top/bottom surface generated is not smooth (https://sites.google.com/site/snappy...ightblock_.png)
while if i use small blockMesh (smaller than the cylinder) , the surface of top/bottom is quite good (https://sites.google.com/site/snappy...mallblock_.png).
Since I need the background block as a water tank and to test the forces on the cylinder, could I use any utility like Cellset to "define" a small region in the block as a background mesh for cylinder, or maybe with 2 blockMesh, one small block for generating cylinder and one for water tank?

Many thanks,
Cloudy