SimScale CAE Forum

Step-by-Step Tutorial: Homework of Session 4


Hi @kpetersen,

It looks like Inventor uses mm as the base unit, while SimScale uses meters.

If you have a local installation of OpenFOAM, it’s quite easy to scale the geometry. You just have to use the following command with the appropriate scaling factor (e.g., if you want to go from m to mm):

surfaceConvert -scale 1000 input.stl output.stl


Hey @ kpetersen, from the picture all what you have to do is to rotate your model 90° and scale it by a factor 0.1.


Hi @Akrem, I’ve finally managed to convert it properly by using Solidworks, so seems like the cause of the bad conversion was Inventor itself. Thank you for your kind assistance.


I can’t manage to move the front wing where it should be. This is the situation right now.
I’ve tried both with Notepad++ and with the script.
Is there any other way?


Do you have a generated project link for me so that I can do my simulation with the fixed assembly myself? I would love to see the results bc it is my wing :slight_smile: thank you.


You can copy any public project into your dashboard with Actions > Make a copy. Then, just get rid of of anything you don’t need or want within the project.

You can also download the geometry if you right click on it in the tree.



Hey guys!
I’ve created my model via an assembly in PTC Creo Parametric 3.0, and in my “faces”, there is only one model. What can I do? @jousefm @Akrem
Project link
Also, I think I may run out of computing hours, due to an incorrect simulation that took a great deal of them. What can I do in this case?
Thanks in advance!
Best regards,



is it possible that you upload the car without the frontwing as a STEP Modell? Inventor 2015, that I use, has some problems with importing the STL file.

Philipp Biedenkopf


@Akrem I’m having trouble getting the CAD file working. I’ve tried uploading the stl file into OnShape and using FreeCAD to convert the stl file provided into a STEP file, then uploading to OnShape. Neither worked. OnShape keeps saying the translation failed. I also tried exporting as an inventor file (.iv) then uploading into OnShape. How can I get this to work successfully?


@Akrem I created the CAD model of the front wing with SolidWorks but it has only one part.


So I am using solidworks 14 and after conversion using both the techniques, I am getting this result, i.e., front wing assembly interfering with the diffuser as opposed to the first pic(where it should be). Please help. Fast.


ciao…ma come caspita si fa a inserire l’ala creata da noi con la macchina data da loro?? non mi fa fare l’assieme con solidworks…



I am having the same problem as happy_gerrard in which my front wing intersects with the diffuser in the final STL file, I have been trying to solve this problem for days without success. I was wondering if there is another solution for this problem or if it is possible that you upload the car without the front wing in STEP format so I can assembly it together with my front wing and then import it in STL format.
Best regards


Hi @happy_gerrard, @juansan995

It seems like you have created your wing around the center of coordinates (0, 0, 0). So, when you merge the two geometries, it places the wing were you created it because the merge utility does not know better.

Before creating the STL file for the wing, move it along the x axis so that the front is at -1.486 m. This should put the wing in the correct position in reference to the car.


hi…in solidworks i cannot split my wing into main wing, flap etc…how i can do?? if i extrude each part with different sketches, the result is the same…


i move the front wing before the conversion, but after the conversion the result is the same…solidworks cannot convert the wing in the right position


Try ticking off the option Do not translate STL output data to positive space which makes exported parts maintain their original position in global space, relative to the origin.


Non convertire i dati STL esportati in spazio positivo


aaaaaaahhhhh thank you man…


Gretings @pfernandez

Thank you for your help, I have tried this but the wing appears in the same place again, are there other solutions that I could try?

Best regards.