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-   -   [ANSYS Meshing] Meshing of a 3d Ringwing in a cylindrical enclosure (http://www.cfd-online.com/Forums/ansys-meshing/102766-meshing-3d-ringwing-cylindrical-enclosure.html)

Lukas_ZH June 1, 2012 12:01

Meshing of a 3d Ringwing in a cylindrical enclosure
 
Hi everyone,

I just got a semesterproject assigned to setup a analysis of a closed ringwing in Fluent and are completely new to Ansys Workbench. I got an idea working woth the cornell modules before they got "locked" a few days ago.

Anyways, the original idea was to use my predecessors' Matlab script which creates a directly a geometry file of the ringwing for Ansys. First it creates an airfoil based on some parameters, alignes up to 6 profiles equaly spaced in a circular pattern and connects the profiles with splines. The airfoils are "spline-based" too.

I used then the enclosure function to create the windtunnel. Through named selections, I defined the airfoil as itself, the back end as outlet and the rest of the enclosure as inlet. But as soon as I start the Meshing in Fluent, it always gives me an error message about a problematic geometry and aborts the process.

Another approach I tried is to create, based on a coordinate .txt file, an airfoil in the xy-plane which is offset in the y-direction. Then create a line, then a surface and then revolve the whole thing around the x-axis to create the wing. After that, creating the enclosure. I tried the different "automatic" meshing options. The Fluent ones either come up with an error message concerning problematic geometry or that the meshing ran out of memory. If I mesh it with CFX, it looks ok except for the trailing edge which is unusable (looks like pieces have been broken off it).

Sketching a rectangular or elliptic profile and doing the same procedure as the one with reading the file, the mesh generator seems to work fine (though it looked that the trailing edge of the ellipse wasn't a 100% smooth either).

I thought about splitting the enclosure into two parts, just as in the airfoil tutorial of cornell, to create the mesh. Though I can't say if that is going to help at all in 3d.

No I would like if anybody out there might have a suggestion or an idea for a different approach or any thoughts how to fix the problem with the meshing.

Thanks a lot in advance for your advice.

Best Regards,

Lukas

Far June 1, 2012 12:36

Quote:

just got a semesterproject assigned to setup a analysis of a closed ringwing in Fluent and are completely new to Ansys Workbench. I got an idea working woth the cornell modules before they got "locked" a few days ago.
you can email them to make an account for you.

Lukas_ZH June 5, 2012 04:04

Thanks for the info. Right now it seems they're open for the public again.

Best Regards,

Lukas

Bollonga July 4, 2012 04:06

Hi everyone,

I have exactly the same problem, I have to mesh the volume around a ringwing with three blades. I've created a cilindrical enclosure and made a boolean sustraction in Design Modeller and it all went okay. But when it comes to the meshing (Ansys 12.1 ICEM Meshing) it gives two error messages saying:

Error: A mesh could not be generated using the current meshing options and settings. Hint: The problem geometry areas might have been highlighted. Switching to wireframe mode may make them more visible.

Error: The following surfaces cannot be meshed with acceptable quality. Try using a different element size or virtual topology.

I have tried many of the meshing options (sizing on curvature, local and global sizing, local mapping, etc), I've divided the domain into sectors.

As I've meshed some parts of the model by themselves (not closing the circle) and it went okay I guess the solids are okay. They give no error in Entity checking in Solidworks either.

Any suggestion?

Thanks!

Far July 4, 2012 06:58

http://www.cfd-online.com/Forums/ans...osed-wing.html

bennyipfar March 14, 2015 06:49

I fix the topology error in my model by forming my model into one body muti-parts and hit "share topology" in DM geometry. The second one I am still struggling! Can someone shed some light how to get rid of that?


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