Hello, I am trying to get a wind tunnel simulation test on a B77W aircraft for a University project. When I try to run the simulation, it gives me this error message.
A setup with at least 180 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.
It seems like you’re working with the Incompressible Analysis Type, which means the only part of the geometry you want present to the simulation setup is the Flow Region, and not the solid bodies of the aircraft itself. The tutorial above begins with how to prepare your geometry for a aerodynamic flow simulation. Since this kind of CFD simulation only simulates the flow around the body, the CAD body/geometry should represent the air volume you’re simulating, with a ‘cutout’ where the solid bodies are.
Feel free to reply here with an update if the tutorial and note above got you going in the right direction or if you need further assistance.
After checking out the project on your dashboard, I noticed you were also trying to model the fan rotation. I’d recommend keeping the model simple as you learn the ropes with CFD simulation. Your first step is definitely to creating the Flow Region body around the aircraft model then deleting the aircraft body. I would give this a shot without the engine/nacelles so that you can successfully mesh the body in a similar manner to what is presented in the tutorial.
From there, you can progress to modeling more complex features, including the engine fan rotation. Be sure to utilize symmetry so that your simulation can run more efficiently by only using half the model while still obtaining valid results.
You can use the wing model from from the tutorial. Just select the blue “Import tutorial to Workbench” button to bring the model into your own project to follow along with the tutorial. You can use the Incompressible analysis type and work with a speed below Mach = 0.3 for valid results; otherwise, the rest of the setup conditions are the same/similar.
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.
What does this error mean? It’s my last one before it runs correctly!
You’ll want to delete the “Wing” body from the geometry, that way, you’re only working with the flow domain. Review the geometry creation portion again in the tutorial linked, where you need to delete the wing body after the flow region was created.
Your final simulation setup for any conventional CFD simulation should only have the Flow Region body. To calculate the forces on the wing body, you select the surfaces of the wing that are a part of the Flow Region body (Compressible Flow Around a Wing | Tutorial | SimScale).
The flow will be dominant in the negative-z direction, but have a component in the positive-y direction, which corresponds to a realistic angle of attack between 0-16 degrees; there shouldn’t be an x-component to the velocity (i.e. side slip flow) that is near the order of magnitude of the main flow direction (negative-z) if you want reasonable results.
Take your time when going through the tutorial and be sure to understand each step. That will get you on your way to succeeding with CFD simulation.