XFLR5 vs CFD

Thanks Jousef but darn, I thought we were resolving the viscous boundary layer by layering the mesh. How do I directly resolve the viscous sublayer so I can see the separation?

I finally figured how write control got changed to 1s and then why it just hung around :bulb::bulb:

When I was playing around with making 1s simulations trying to see yPlus ranges I must have HAD to do it, just so I could get the sim to run.

And actually it was even worse than that, I did not realize that the >Details below ā€˜Write Controlā€™ input box was a dropdown to a variable (I thought it was a heading for the parameters that followed), so the only way I could get a 1s simulation to run was to change Write control to ā€˜Adjustable runtimeā€™ and that automatically changed the hidden ā€˜Write Intervalā€™ value to 1sā€¦ :face_with_raised_eyebrow::face_with_raised_eyebrow::face_with_raised_eyebrow:

I just did not realize the consequences of doing so back thenā€¦ (but I did not seem to consistently get Out of Memory errors, just hang-ups). BTW, no hangups :slight_smile: since I have seen the light and put write back to length of sim (which BTW I have been running lengths at 400s lately, I figure if not converged at 400s, why go to 1000s).

And then it just hung around since I have been duplicating simulations to act as a template just so I donā€™t enter everything again. Maybe there needs to be various ā€˜templatesā€™ for simulations that you can save and rename :wink:

What would ever be the reason to have a sim ā€˜stepā€™ at anything but 1s?

No scenario in a steady state simulation that I can think off, really applicable in transient simulations, where time step size makes a big difference, not only to the result accuracy but the stability of the simulation.

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I see that your Custom Inlet/Outlet Boundary condition also uses customized values for k=9.126000000000002e-9 and omega=0.006166216216216216 while the default values for k and omega in my Initial conditions are k=0.000001612 and omega=3.375.

To be consistent with all my other simulations in this project, I assume that I DO NOT use the values you used.

And is it sufficient to just leave them as initial conditions and not also set them in the Custom boundary condition?

Thanks Dale

Hi @DaleKramer!

There is a SimWiki post about that topic which might be interesting for you (it is from Darren btw :slight_smile: ): Defining Turbulent Boundary Conditions

Cheers!

Jousef

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