@KyleDavisSA I tried the setting, I think including Forces0 in the acceleration surely helped.
Before including the forces in the acceleration, the forces applied on the flap were in the magnitudes of *e+03.
Now they have come down to the magnitudes of *e+02. I think I have to modify my OpenFOAM adapter further since this seems to be a case similar to the post by Ulrich.
I have made the modifications implemented, but not sure.
I will have a look at my adapter again.
For <time-window-size value="1.e-3" />, it run until almost t=0.03, which was similar to what I got before.
For <time-window-size value="1.e-4" />, it run until t=0.538698, which is better than the explicit coupling with similar <time-window-size.
Unfortunately, the actual results are the same as before.
I am trying a case where the solid is a kind of a ramp, might have better results.
