SimScale CAE Forum

I cant create the External Flow Volume Mesh

Good Afternoon,
I’m a 17 y.o. without any kind on experience in aerodynamics neither simscale.

I’m trying to see the aerodynamics of a drone that i modeled myself for a project at school, and when i want to create the flow volume, an error pops up saying: “A flow volume could not be created since there are no solid bodies in the model. Please try to thicken or extrude the sheet bodies to make them solid.” I’ve tried cleaning the model, removing all errors and simplifying uncommon geometry, but the error still pops up.

What can i do to create the simulation?

imagen_2021-09-16_180521 imagen_2021-09-16_180629

Hi @odiaz_a, I had a quick look at your project and it looks like you have a mesh and also a simulation that is running.

Please consider updating the post with the solution!


Oh, I copied the wrong link, sorry for the inconvinience.

Here is the correct project, with the problem:

This one works better, thanks.

In short, a sheet body is a non-watertight geometry. It consists of faces only, and it’s completely hollow inside (i.e. it has no volume).

Repairing this kind of geometry can be very tricky (see this article). It consists of finding where the holes in the topology are, and closing them. The idea is not to have any free boundaries/naked edges that cause the geometry to be non-watertight.

Typically the best tool to fix the issue is the same one that constructed the geometry.

On a side note, I would really recommend using a smoother geometry for the simulation, the topology is quite detailed with hundreds of small faces:

This doesn’t mean that the CAD model is wrong, just that it’s not very good for a CFD simulation. I don’t think it’s possible to run a model this complex with a community account.

The other model that you linked (which is working) is definitely cleaner.


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Okey! Thanks for the Advice and explanation! I will try to simplify the model and start from there.

PD: Can I quote you in my Project sources? Its mandatory to quote people that helped you. But, if you prefear to not be mentioned in some random students work project, i can make you anonymous.

But really thankfull for the help given! <3

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No worries - feel free to quote me :+1: