i would like to explore possibility of using Fluent/fidap for structure/fluid interaction. could you direct me to a simple example already done to show me the basics of how the codes should be used. thank you

FiDAP has an FSI model incorporated in the code. FLUENT does not...explicitly, that is. You can use the moving-deforming mesh capability or couple FLUENT with an FEA code. An example of this was reported in a Fluent newsletter some time back. The FEA code was Abaqus.

thank you for your answer. So you recommend to use FIDAP if i have the choice instead of FLUENT. what is the easiest to use for the beginning?

FiDAP contains an excellent CFD solver in it's guts. As I mentioned previously, FLUENT may be able to tackle your problem. Take a look at the product specs for both codes. Post your problem description on the FiDAP and FLUENT discussion page. You need to find the tool that will address your problem now. If you have not yet come to conclusion by this point, contact Fluent Inc. and have the sales engineer come up with a solution that incorporates the main physics of your problem of interest. Cheers.

I will be glad to help you in defining the best way to solve the problem....but I need some more details!!!!