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convexengineering / SPaircraft

Models for commercial aircraft design
http://spaircraft.readthedocs.org
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VSP updates #59

Closed mayork closed 7 years ago

mayork commented 7 years ago

@1ozturkbe I'd like to see vsp for the 777esque D8, the D8 with the engine on the wings, and the D8 with the 737 engine

1ozturkbe commented 7 years ago

Good idea, but I am really busy until Wednesday with Aviation paper. Will have to wait until afterwards. Btw, can you run VSP on your Mac at all?

mayork commented 7 years ago

haven't tried to set it up

1ozturkbe commented 7 years ago

Update: works with all A/C I know of. Issues with horizontal tails for D8 configurations. Still trying to decide how to make sure engines under wings do not look wonky.

mayork commented 7 years ago

we should get 777 class and RJ class VSP

1ozturkbe commented 7 years ago

Can do quickly, now that everything VSP is fixed. Should be up in 30 mins.

1ozturkbe commented 7 years ago

This has been done. The RJ has a really small HT, not sure exactly why. Will check out.

mayork commented 7 years ago

i think we undersize HT cause we hit the min static margin where as TASOPT never hits it

1ozturkbe commented 7 years ago

It's funny you say that, because the SM constraint is actually not tight. Our SM is 6.3%, whereas the min is 5%. Probably because of the min CL constraint on the HT. And we have a horizontal tail coeff of 0.7, which seems quite reasonable.

1ozturkbe commented 7 years ago

Another reason the tail looks small is because the fuselage is blocking part of it :P. Should I adapt the VSP to fix this issue? (I did it with the VT.)

1ozturkbe commented 7 years ago

Actually, I'm just going to implement this, and regenerate the RJ plots, because they look quite wonky. Other than the graphical bit, the HT is well-behaved from a modeling perspective.

mayork commented 7 years ago

So in TASOPT the min static margin generally hovers around 0.3 so we're still a lot under

mayork commented 7 years ago

in the validation cases I set the static margin to the min in the TASOPT output so those tails match better, but for the morphing analysis I keep a constant 0.05

1ozturkbe commented 7 years ago

I don't see any reason to match the 0.3 static margin, other than in the validation cases. This is great. You can let me know in this thread if more VSP updates are required. But for now, closing.