I want know about the difference between the lagrangioan approach and eularian approach. I also know anout how can I have some literature about these two basic approach?

Simply stated:

Langrangian... moving reference frame Eulerian... fixed reference frame

Most CFD software adopts the Eulerian approach, although the derivation of the Navier-Stokes equations can use either approach & then convert between each, as required.

Versteeg has an excellent book.

diaw...

Hi, anybody can send me some preliminary soft material so the I can get initiated with CFD. Regards, Biswajit Sarkar

What kind of soft material do you need. Do you need a code, or some algorithm to write your own code. Codes you can download. There are many sites on which codes for CFD are available. Usually most of them use Eulerian approach.