Info Tessellation

[Federico Feraiorni]

Good afternoon,

I am currently working on the following geometry. Using the VLM solver with the settings shown in the screenshots (all references and fluid conditions taken from experimental paper), I have noticed significant discrepancies between my results and the wind tunnel experimental data (orange for VSPAERO, blue for wind tunnel).

Could you please help me identify what might be causing these differences? Can be the tessellation?

Thanks in advance for your attention.

[Brandon Litherland]

There could be any number of reasons why the results don't align.  Unfortunately, we can't assess the reason with the information that you've provided.  Do you have a published report for your tunnel data? Are you using the same reference area and dynamic pressure to normalize your coefficients? 

[Federico Feraiorni]

Hi Brandon,

Thank you for your response.

I am conducting the analysis under the same flow conditions (Re, M, alpha) and using the same reference dimensions as specified in the report. Specifically, I am focusing on the Mach 2.16 case; the reference geometry parameters are listed on pages 6 and 7, while the flow conditions are detailed on page 10. The corresponding validation plots can be found on pages 31 and 32.

Since I am still familiarizing myself with the software, and given that I have already matched all the VSPAERO settings i could (Re, M, alpha,Sref, bref, cref) to the paper’s specifications, I suspected the current discrepancy might be due to the surface tessellation or mesh quality.

[Hans]

It seems that the vspaero doesn't perfectly cautch an impact of the body on the lift. I was analyzing some UAV models and the fuselage section usually is not good taken into account by the software. In general, the lift is higher than the software results. Also, you used the angles which exceed the 15 degree "rule", so it's not appropriate to use for further angles because of the divergent results.

ср, 11 лют. 2026 р. о 02:09 Federico Feraiorni <fede...@gmail.com> пише:

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