SimScale CAE Forum

Rotating Wheel Project Support

Hey,

I am currently testing the coefficient of drag on two variables and one constant. The simulation is based on a front bicycle wheel traveling at 12.5m/s. Outlined below are the test variables and constant (currently only Variable_1 has been tested).

  • Constant : Wheel without anything on it

  • Variable_1 : Wheel with an aerodynamic weight

-Variable_2 : Wheel with blue tack, or weight strips

My question:
My question is should I input the specific center of rotation for each system i.e constant, varialbe_1, and variable_2, or should I keep the center of rotation constant for every system?

The coefficient of drag results have been produced using an ‘MRF rotating zone’, ‘Topological entity’ and ‘Force and moments coefficient’. I am assuming these are all correct parameters to be using?

Thanks for the support.

Tanguy Pinol

Hi Tanguy,

The center of rotation does not affect the drag coefficient. It only has an effect on the moment coefficients. As such, I think that you can leave it constant across the different models.

Yes, by what you mention it sounds ok. We could perform a better assessment if you share the URL to your project!

Hi,

Thank you for the support. I have shared the link to my project with you:

https://www.simscale.com/projects/tpinol/mrf_wheel_with_weight/

I would like to perform a sweep in order to test various yaw angles ranging from -15 to 15 in order to get the most amount of data possible.

Is there a current function that is able to do this, similar to the MRF function or do each yaw angles have to be tested separately when setting inlet boundaries.

Thanks for your amazing support!

You are welcome!

To test the yaw angles you could play with the inlet velocity vector, but I think that for this you need a different flow region. I have seen this approach in papers concerning aerodynamic profiles and angle of attacks, where they use a circular or semi-circular region. Research a little and you might find ideas.

Another possible approach is to use the CAD Edit mode to rotate the wheel before creating the Flow region, thus you don’t need to go back to CAD and import your geometry. You then just duplicate your simulation, switch to the new geometry and apply all assignments.