Reply To: About particle floating
it depends on the way you changed the parameter and what you inspected. If the cubes density is below the fluid density it will rise to the top. It is relevant where you changed the densities as they enter “externalAcceleration” for the calculating of buoyant forces.
Depending on the density difference the particle might accelerate rapidly in this case it is possible for high velocities that the cube slips through the wall, in which case it no longer experiences drag forces. You might want to check if this is the case by checking wheater the cubes coordinates are still within the simulation domain.
To the orientation: The parameter sets the initial orientation. Wheather the cube rotates and to which extend is not always trivial as it depends on initial orientation, Reynolds number, density ratio, …
Did you have a look at the terminal output or the vtk output files? It is possible that e.g. the rotation is rather slow and therefore not visible when inspecting the graphical output.