Hi,

I wonder has anybody encountered this error, it is a very simple aerofoil geometry, and when I am trying to create the boundary layer mesh on it, it reports:

Unable to attach boundary layer on edge xxx.3 of face xxx, Please consider changing the boundary layer vertex type at vertex xxx of face xxx to SIDE.

What does this mean?

Many thanks

Check out the Gambit Manual for vertex type definitions. The three most common types are:

end (the geometry puts the mesh on an inside corner... i.e. the end vertex only has one cell touching it... think of the 4 corners on a rectangle)

corner (the geometry puts the mesh on an outside corner... i.e. the corner vertex has three cells touching it... think of the corner on a backward facing step)

or side (the side vertex has two cells touching it... if you put a vertex on a straight edge, this would be a side vertex... this works just as well if the angle the two edges makes are close to 180degrees... it's as if the edge were continuous).

Vertex definitions are set for each vertex on each face. Gambit makes assumptions of the vertex types based on the angle edges make with one another. Sometimes the vertex type Gambit chose doesn't match what is needed for the mesh. That's what the error message is telling you. To change the vertex type, go to the vertex type in the face mesh commands and try changing vertex XXX of face XXX to SIDE. You'll have to find which face it's talking about, and which vertex on the face.

Hope this helps, and good luck, Jason

many thanks - problem solved.