SimScale CAE Forum

Erroneous Simulation - Rear Wing FSAE CFD Analysis


#1

I am trying to simulate a wing in water. The meshing seems to be of decent quality now, but i cannot get the simulation to run, it just errors without any log or explanation.

any sugesstions to where it errors out??

The simulation definition

https://www.simscale.com/projects/akhm74/h-kspoiler02_1/


#2

Hi @akhm74!

The mesh is too coarse at the moment. I would just follow this tutorial which gives you a good impression on how to create an adequate model: Step-by-Step Tutorial Session 1 - Front Wing Design Study (Part 1). If you have any questions you can ask me anytime.


Cheers,

Jousef


#3

The tutorial is the basis for my project, and it is rather comprehensive.
The simulation did run on a less fine mesh, (LC1 Medium2), but as the boundary layer has been added to the mesh (LC1 Medium 3), it just fails…

I know the bounding box mesh is coarse, but i have refined rather heavily through 3 regions and with surface and feature refining i am down to a “pretty” ok mesh on the geometry. I want to refine to the smaller details on the geometry, keeping core hours to a low.


#4

Hi there @akhm74!

Will have a closer look at the issue tomorrow morning if you have not figured it out yet. I also saw that you could make it work with adjusted settings but I would still argue that the mesh is too coarse and you would have to perform a mesh convergence study anyway so let’s keep the sim now and definitely compare it to one that has double the fineness/half the grid width.

Cheers!

Jousef


#5

Hi Jousef,
I did by mistake delete the sim in question. I am currently recreating the sim. (LC1 Medium 3 - Run 1)

I will also try a smaller bounding box, but with finer mesh initial mesh. I am hitting memory issues with 0.5x0.5m initial mesh, trying a ~0.625x0.625. Less level of refinement should result in a decent boundary layer.

Btw: I have gotten the mesh without boundary layer inflation (LC1 Medium2 - Run 4) to finish without any issues. Seems like convergence is reached at approx 300s (it did require a very long max run time…)

Thanks for now.


#6

Sounds good @akhm74!

Let me know if you need any help :slight_smile:

Cheers!

Jousef


#7

It is starting convergence plot, so there is hope…


#8

Hi @akhm74,

Just checked your latest run. Looks good so you can proceed to post-process from there and fine tune the results if they are out of margin.

Cheers.

Regards,
Barry