[arun1994]

I am trying to make transient analysis for a simplified piston model with single intake and single outlet. I have shown it in picture 1 .

I have a problem with "negative volume " . I know my mesh is very bad . The surface mesh is pretty good to look from outside but inside using section plane ,it looks very bad as in pic 2.

How do I make a hexagonal mesh which are same in size ? Is it possible that I can "extrude " mesh from the base till the top ?
What are best practices to make hexa mesh ?
Also is there a comprehensive tutorial/PDF to read for transient analysis ?

Probably there are a lot of posts on this but I have less time now to search all. It will be nice to get specific answer for my problem.

Cheers,
Arun