RM
Ansys Employee

Hi,

As you are new to Ansys, I recommend going over this tutorial in the Ansys documentation that shows a 2-way FSI simulation with Fluent and Mechanical. https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_tut/sysc_tut_reedvalve_fluent.html

In remeshing tab,

A good starting point for the length scales are 0.4Lmin, 1.4Lmax.

Decreas maximum skewness from its default value. Keeping remshing interval low (if kept high will cause negative cell volume detected error)

Also, try to improve the quality of initial mesh