フリーのPrePost環境Salomeについて。
特にSaome-mecaと呼ばれる環境はCodeAsterにより構造解析までSalome上で出来る。

http://www.salome-platform.org/

SALOME is an open-source software that provides a generic platform for Pre- and Post-Processing for numerical simulation.
It is based on an open and flexible architecture made of reusable components.