[James_]

Hello,

Sometimes during tools use such as extrusion or grid solve you can see a yellow circle. What does it mean?


regards
James

[cnsidero]

James_

For the elliptic smoothing, being an elliptic boundary value problem that uses an iterative method to solve, I believe the circle indicates the location of the maximum residual.

For the hyperbolic extrusion, being a hyperbolic initial value problem, I'm not 100% sure as each iteration represents the next layer in the mesh. Perhaps it's the location of maximum point advancement.

Someone from Pointwise is going to have to chime to give more scientific answer to your question.

-Chris

Originally Posted by James_

Hello,

Sometimes during tools use such as extrusion or grid solve you can see a yellow circle. What does it mean?


regards
James

[James_]

Thanks, Chris

[jchawner]

James:

Chris is correct. For the elliptic PDE solver for a volume grid, the circle appears at the point of maximum residual.

I couldn't make the circle appear when doing Create, Extrude and am drawing a blank on what it could mean.

Are you running Pointwise or Gridgen?

[James_]

Thanks John for your answer.


I’m using Pointwise.
My little experience says: if you see a yellow circle during extrusion you will have problems in next steps. But it is not a rule.
In the attached picture you can see a circle appears during extrusion operation. It would be nice to know what kind of problem is indicated by this circle

[jchawner]

Well, that took longer than it should have. During extrusion, the yellow circle is centered on the point of the current front with the largest step size from its previous location. So I can imagine that large step sizes are the sign of divergence, although the image you show looks fairly benign.

One thing I'll advise is that if you're extruding structured grids using the normal (aka hyperbolic) method, always set the Kinsey-Barth smoothing parameters to a value of 3, especially if you have concave regions like the one shown above.

Also keep in mind that for the traditional extrusion solvers there's only so much you can do coming out of a concave corner like that. Our tech support can tell you which parameters to alter to get it out as far as you can.

[James_]

Thank you very much John especially for your hints about extrusion settings


Regards