Setup with 2 regions being used

Hello. I am trying to make a project in which air blows at 10m/s on the plane model I have designed. I imported my .stl, went into CAD mode to add a flow region, then created a simultion. However, when I try to run it, I get the following error:

A setup with at least 2 regions is being used in a single-region analysis type. Please ensure that only one fluid region exists and that all other bodies are assigned to an advanced concept. If you have already meshed your geometry, ensure that all the meshing regions except one are cell zones.

I was wondering if anybody could help me as to how to solve this issue. I do not see how there are 2 regions in my setup.

Here is the link to the project: SimScale Login

Hi there,

Thanks for using our Forum, this is Ajit from the team.

I see that you have followed the Fluid volume creation operation in the CAD Mode. But for an external flow analysis using Incompressible required just the flow region and not the solid body of the plane.

Steps to correct this:

  1. After creating the External Flow volume, delete the body of the plane
  2. Re-Export the model with just the Flow volume.
    This will avoid the error with 2 regions.

Here is a sample tutorial which follows the exact workflow I mentioned above: Incompressible Turbulent Flow Around a Spoiler | SimScale

Quick note: I would make sure you follow the recommended dimensions of the flow volume for better results.

With Kind Regards,
Ajit