Hi everybody,
Does anyone know whether it is possible to evaluate the force acting on a rotating body that interacts with both fluid and solid particles and the corresponding torques?
Thank you for your help.
I’m not sure I understand the question. What’s driving the rotation? In a case like the 3D mixer tutorial, you are controlling the speed of the mixer, so you can compute the (constant) torque directly - but I think you may be looking for something else … are you looking for the torque contributions from particle collisions?
Exactly, the moment produced by the rotor that also includes the forces exerted by the particles on the rotating part. In the case that the rotor simply rotates without any interaction with particles only with the medium (air) the torque can be calculated by the product Force X Position [N-m]. But including particles they will introduce extra power consumption by the rotor. Is it possible at all to compute forces exerted on solid (stl) rotating parts?
Thanks Charles.
I wanted to mention that in the latest MFiX release (24.3) we have options to save collision force to the VTK output file. This may be helpful, although (A) it includes inter-particle collision forces as well as particle-wall collisions and (B) of course to compute torque you need both force and position along the rotor where the collision occurred.
If you are still working on this - you probably need to add some custom code, see the file des/calc_collsion_wall_mod.f around line 516 where the normal contact force FNORM is computed. You could add something there to compute the torque on the rotor and store that into a user variable.