Medical robot simulation
 

Hello Everyone, I'm currently doing my bachelor's degree in Mechatronics and we are having a really tough time in our project.

I am simulating a micro-robot in a fluid flow to be able to understand it's propulsion characteristics throughout the drag forces that occur on this micro-swimmer.

Basically my problem is that I never used ANSYS, and the simulation results are always wrong and not repeatable for different rotational values. let me explain what I have to simulate so you have a good understanding:
a helical micro-robot, a robot which rotates around itself because of outer magnetic field thus from rotating at different RPMs different axial velocities are achieved it's basically like a screw rotation, but in fluid. the shape is very simple a helix attached to a very small cylinder magnet nothing more.

I have the geometry from solid-works, mesh it on ANSYS and setup the problem but I have no idea if it's correct setup or not:

I use the following:

1. K-epsilon model with default values
2. velocity inlet (either 1 or 2 m/s values, gauge pressure 0)
3. pressure outlet with 0 gauge pressure
4. Fluid is glycerin whatever it doesn't really matter
5. I use pressure based solver


and the robot itself is read as a wall, additionally rotates around the (1,0,0) axes with 10 rad/s (at this point I need to simulate different values for rotational speed for a graph plot of the behavior)
I also use a screen monitor for the Drag coefficient.
I specify 1000 iterations but at after 280 it says Solution is converged!

Any idea where did I go wrong? I'm pretty sure in almost everything but I have zero knowledge with ANSYS and I have to have results and valid ones specially I have to publish a paper, also if anyone has recommendation or able to help with problem setup I would be really glad.