OpenVSP crash

[jason]

Good day all,

I have made a model of the wing and the tail without the fuselage, but when I run the analysis using the panel method, openVSP crashes. Why would it crash?

Attached is a picture of the model that I have developed. 

Regard

Jason

[Rob McDonald]

Did you make the vertical tail by first turning off symmetry -- and then rotating 90 deg about X?  Or did you just rotate 90 without turning off symmetry?

I suspect your vertical tail is actually two identical vertical tails on top of one another -- this will give CompGeom fits before VSPAERO runs.

You will need more spanwise resolution to get good results.

Rob

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[jason]

hi Rob, 

Thanks for helping.

I just rotate 90 deg without turning off the symmetry. So you suggest that I do otherwise?

copy on the more spanwise for better results.

jason

[Rob McDonald]

Yes,

For your vertical tail, on the XForm tab, in the middle of the GUI, there is a button for XZ planar symmetry.  Turn it off.

To increase spanwise resolution, go to the Sect tab and increase the value in Num U.  I would increase the wing resolution to 15 or so and then increase the tail resolution to 10 or so.  You can play with it from there.

Rob

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[jason]

ok, thanks Rob.

However, after making the changes, the program crashes again.

attached is the selection on Xform tab .

jason

[Brandon Litherland]

Isolate each component and try to run VSPAERO to find the culprit.  There are several things that will kill a Panel run including blunt TEs, flat vertical surfaces on bodies, coincident or nearly coincident surfaces, bad intersections, ... 

It is much easier for us to determine the source of these problems if you can upload an example file that exhibits the behavior.  Short of that, searching the Google Group topics will generally give you lots of information to go on and users may find that they can discover and address the problem themselves.

[jason]

good day,

I have tried isolating, once I removed the horizontal and vertical tail, I was able to run panel analysis.

However, if I add back either the horizontal or vertical tail, the software crashes again.

Could it be due to the gap between the wing and the tail, that causes the software to crash?
Thanks for the advice.

[Rob McDonald]

It is more likely the nasty intersection between the vertical and horizontal tails.  In this case, you would probably benefit from some sort of fuselage.  It will swallow those nasty joints and simplify things a bit.

Assuming you're running Panel mode as you mentioned earlier.

Beyond that, we really can't help unless you can post your file for others to check out.  Right now, we're just throwing out common pitfalls hoping that one is what you've hit.

Rob

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[jason]

Good day Rob,

I have also tried removing the main wing by just running a panel analysis on the vertical and horizontal tail. 

It is able to conduct the analysis on the tail section. 

Attached is the project file.

Appreciate your effort for helping me.

thanks

jason