FSI, contained fluid,must also use contact elements? 1

[micmaf]

I am studying the behaviour of a water tank "blocked" at base; for the steel structure I have used SHELL63 elements, for the fluid FLUID80 elements. At boundary I have imposed that nodes of the fluid and those of the structure have the same displacement in the direction normal to the interface.
I have done a transient analysis (full) applying an impulsive displacement (triangular),I have considered gravity acceleration (ACEL), but I obtain too large displacement of free surface. Maybe is necessary modelling a contact between fluid and structure?
Help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[micmaf]

Now I'm hopeless, help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[cbrn]

Hi,
what I know about ANSYS hardly covers what you ask, but I write here the first - and only, unfortunately... - things which came to mind after reading your post:
do you have something in your model that accounts for the fluid viscosity?
Also, contacts would be helpful if you need to insert some kind of dissipation due to friction (friction between the fluid and the walls)

Hope this gives you some ideas...

Regards

 

[micmaf]

Thanks for the interest cbrn. I have given the viscosity of the water (0.0011 Ns/m2) with VISC real constants for FLUID80, but however it has little influence, I think that my boundary conditions are correct to simulate a fluid structure interaction (no friction need),unfortunately nobody dealt with similar problem in this forum.