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-   -   [ANSYS Meshing] Help - Meshing 2 Surfaces On A 2D Geometry (https://www.cfd-online.com/Forums/ansys-meshing/85238-help-meshing-2-surfaces-2d-geometry.html)

 Ali_M February 21, 2011 04:14

Help - Meshing 2 Surfaces On A 2D Geometry

3 Attachment(s)
I'm a student trying to mesh a flow field for a research paper, and I've run across a few issues that I'm not sure on how to fix. I have very limited Ansys design modeler and mesher experience, so I've been making extremely small progress by just playing around with the software and reading the help files.

First, background: I've attached a picture of the geometry. The geometry consists of 2 un-extruded surfaces (airfoil, ramp). I had some data points from an experimental setup and I imported them into DesignModeler and made a 3D curve. I wanted to do a more sophisticated bounding box, but I was unable to get Ansys to comply, so I decided to go with a simple box setup.

The ultimate goal is to be able to mesh this flow field and simulate a hypersonic flow, and if all else is well, attempt to simulate a blast wave focused on the airfoil using a pressure source as the model.

Second, problem: The problem I'm running into now is that when I try to start meshing the flow field, Ansys also meshes the inside of the airfoil. I've tried several things to fix it, but it still does it. A lot of the grid points are falling right on top of the second surface. I ran a quick auto-mesh generation and attached a picture to show you guys what I mean.

The other problem is that I'm not quite sure how to create regions of high concentration. I'm thinking of using a 'sphere of influence' near important locations, but I'm not sure if there is a better way.

Third, possible solution: The only thing I can think of right now to fix this issue is go back to DesignModeler and extrude the surface by one cell length, and then cut the airfoil out, so Ansys mesher doesn't mesh inside of it.

I'm kind of running short on schedule in trying to figure this out, so I'm really hoping that you guys have some suggestions for me. I'm rather new to this line of software, but I'm sure there is a way to fix my problem. Any help is HIGHLY appreciated.

- Ali

 PSYMN February 22, 2011 09:34

It looks like you have two parts overlapping eachother instead of one part with a hole in it...

 Ali_M February 22, 2011 10:01

Quote:
 Originally Posted by PSYMN (Post 296424) It looks like you have two parts overlapping eachother instead of one part with a hole in it...
Do you know how to create a surface body with a hole in it in DesignModeler. I'm trying to avoid having to extrude the geometry because I want to do 2D analysis.

I never could get the airfoil removed. What would happen is that if I made a surface from the surrounding lines and left the airfoil shape unselected, it would just fill in the part with the airfoil.

Is there another way of doing this or is the extrude/cut the only option?