'Spitfire mk8' simulation project by EachAbyss


#1

I created a new simulation project called 'Spitfire mk8':

First spitfire model


More of my public projects can be found here.


#2

Model source: https://grabcad.com/library/supermarine-spitfire-mk-viii


#3

Awesome model! Looking forward to seeing the results.


#4

@EachAbyss - one thing I’m noticing is that you are using a velocity inlet and outlet. Numerically this can cause issues because it doesn’t allow any wiggle room for small errors. Maybe try a pressure outlet instead?

Have you seen this project, thought it might be helpful: https://www.simscale.com/projects/Ali_Arafat/compressible_aerodynamics_of_commercial_aircraft


#5

Thank you! That project looks like it’s going to be really helpful, i’ve been having real trouble with getting the simulation to run so thanks for your comment! Gonna make the changes and see if it helps


#6

@EachAbyss, I’d love to see it fly, too :slight_smile:


#7

Hi @EachAbyss
A very nice model you have selected there. I see that you are having a lot of simulation crashes. I have taken a quick look at the mesh and setup. It seems that you have some distorted cells in the mesh that might be causing the crashes.

Here’s what I would suggest:
1- Its never a good idea to start with a complicated model that has non-essential parts. So I highly recommend that you “Simplify” , “Clean” and “Remove all non-essential parts” ( for example the ones highlighted in figures) to make the CAD model ready for a CFD simulation. See the CAD preparation guide:

https://docs.simscale.com/docs/content/preprocessing/geometry/cad-preparation.html

2- I would suggest you to use any CAD tool ( e.g Free online CAD ‘OnShape’) to simplify and make the geometry CFD ready. This will help you get a better mesh with no warped/bad cells that cause crashes. for reference as in my project shared by Anna.

I have highlighted some critical regions to simplify in figure below.

So. please try to massively simplify the CAD by removing all small and non-essential parts. This will help alot later on.

If your having any further trouble, let us know.

Best,
Ali


#8

Hey @EachAbyss,


I’ve just found your project. I love warplanes too like Spitfire, Hurricane or Mustang so I’m really interested in this one.

What is your main goal with this simulation?


May I help you with CAD preparation? :slight_smile:

If so, just let me know!


Best regards,

Jani


#9

Hey @EachAbyss,


it’s me again.

I was bored, so I’ve cleaned the CAD already. :smiley:

Feel free to use it: https://cad.onshape.com/documents/41add71755b504ca53492069/w/ff81462552c53d56523ce0c1/e/445e75ee1f5983ac7290d838


Bests,

Jani


#10

Hey @jhorv_th,

This project was actually part of a research project, the project finished so I actually left this half-completed. Thanks for the cleaned CAD! I didn’t have time to do it at the time, think I may take another look into this project


#11

I see, thanks for your feedback! :slight_smile:
Just let us know if you need some support!

Bests,
Jani


#12

I actually would if you wouldn’t mind lending a hand. I’m getting an error when trying to form the mesh off of your model saying ‘Tesselated surface is not closed’. I think the problem is being caused by the air intake underneath the nose, I think it needs a surface covering the hole, like the air intake under the wing. Would you mind taking a look? I’m currently trying to make this change in OnShape however i’ve never used the software before.

Kind Regards,
Harry


#13

Sure, I jump in!

My first guess is that the interference by the rear gear strut is more critical. Usually the air intake shouldn't be a problem. I'll try to create the mesh on my own, then I'll share the results.


In the meantime it is always a good idea to try Onshape and Simscale posibilities on your own. :)


Will be back soon,

Jani


#14

Well, I’m back!
Actually trimming the rear gear strut seems to solve the issue. I’ve managed to create multiple meshes (some of them failed, and look ugly because I play with the parameters).

Depending on the accuracy of simulation it is also a good idea to simplify the model more, like in this picture by @Ali_Arafat https://www.simscale.com/forum/uploads/default/original/2X/a/a78ac898b05a14f096e0a8f588a05f034d007ce9.png

The other thing I did was to scale the model up (length of model 269mm, actual Spitfire is 9.15m long -> I scaled it up by 34).

I’m still not ready finding the ultimate mesh but you can check my project here: https://www.simscale.com/workbench/?pid=427285956862641205#tab_0-0

Have a nice day!

Bests,
Jani


#15

Hi @EachAbyss,

I simplified the model further and managed to generate a quite neat mesh with automatic mesher. I think it’s a good place to start! :slight_smile:
https://www.simscale.com/workbench/?pid=427285956862641205#tab_0-0

Any news on your side? What do you want to investigate with this simulation?

Bests,
Jani