Mohsen, I just noticed that the problem is not coming from "bl", but from the "projectcad" module. I found out that no matter where I increase the order of the mesh, in Gmsh or NekMesh, if I create a mesh with order=7 I get the same error: Wrong number of modes? I don't believe that the specific order of 7 is the issue and it may be true for higher-order meshes. I also tried to manually change NUMMODES in the xml file but it didn't solve the problem. Kind regards syavash On Tue, Apr 25, 2023 at 2:15 PM Mohsen Lahooti < Mohsen.Lahooti@newcastle.ac.uk> wrote:

Hi Syavash,

Could you send the command you used? Also note that to modify the bl, the mesh should have a closed bl with only one layer of mesh. So if using other software to mesh, set it to produce only a single layer that spans from wall to an extent you wish

Cheers Mohsen

Mohsen Lahooti Lecturer in Fluid-Structure Interaction Mechanical Engineering

Newcastle University School of Engineering Stephenson Building Newcastle upon Tyne NE1 7RU UK

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Dear All,

After I converted the mesh to xml format with order=7 (using NekMesh), I tried to split the first layer adjacent to a wall using the "bl" module with nq=7. However, I get the following error:

Wrong number of modes?

Is there an incompatibility issue here?

Kind regards syavash