water damping simulation with fluent
 

Dear folks.

I am currently doing free decay motion simulation with constant spring constant with dynamic mesh and UDF.

initial displacement (physically pulling with initial amplitude) is made from UDF.
After the initial displacement reached as it is designed, the fluid equation is on as the structure is moving.

mesh motion only I found nice oscillatory behavior, and expect to observe damping effect on structure moving due to surrounding water.

once fluid equation is on, I can see pressure spike at the beginning of transient and it is diverged.

I think this kind of simulation is done with other tool (CFX, acusolve) by using ALE method. have anyone done water damping tightly coupled FSI problem simulation with fluent?

any suggestion or sharing experience would be more than welcome.
Thank you in advance.