Patran:maximun wing deflection

[AbdoulKarim]

Hi,
i am currently working on a wing design and i need to define the maximum wing deflexion.
I have already performed the CFD analysis on a 3D wing and obtain all needed data.
I used the FSI mapping on fluent to import the pressure forces in Patran then perform a linear static analysis. however the results don't even appear as something must have gone wrong. maybe i's the method i used. as I am trying to apply the pressure forces on the top and bottom skin (surfaces) of the wing.
my full FEM contain
-a top surface
-a bottom surface
-ribs design as 2D surfaces
-and 2 spars (1D beam)
my questions are :
-Am I right to used the pressure distributions from Fluent to calculate the maximum deflection? in that case, what am I doing wrong, displacement constraint maybe?
-Should I import the forces instead of the pressure, or both? what is really need?
thinks in advance!!

 

[Erik Panos Kostson]

Never done much of wing design.

As for the FSI part mapping and importing pressures should be OK.
This ansys tutorial (fluent) does the same thing with a bit more automation, it basically maps the pressures from fluent on to the structural mesh like you did. So it is mapped on the skin of the wing.

https://www.youtube.com/watch?v=WGjLvSYorNs

I assume for boundary conditions one uses fixed at one side of the wing where it connects to a wing box/ airplane body.

If you post more images someone can have a look and see what happens.

Also perhaps get the total force up lift from fluent or the mapping and then see if that is reasonable from say experience or data or equations for wing design and then use a beam model with that force to see how much deflection one gets. So some verification.

 

[AbdoulKarim]

hey Erik
thank you for your reply, i was out of town. so i couldn't reply on time.
I have successfully imported the pressure values from Fluent however the deflction is insanely huge, either due to the huge value fron the pressure or the unit conversion between the two.
it would be really nice to have a suggestion from you.