Flow Simulation: Simulation of force on aircraft wings

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1

Hello

I have to run a simulation on a symmetrical wing (like an airplane wing), at an angle of 15° and -15°.

The wing normally has a lift coefficient of 1.5 at 15° and  -15° (http://airfoiltools.com/airfoil/details?airfoil=ah81k144wfklappe-il).

Theoretically, with this lift coefficient, applying the lift formula Rz = 1/2 ρ V2.S.Cz

 With a wind of 4m/s, and a kite area of 4m²  I have a lift force of 60N.

Whereas when doing the simulation (flow simu), for the same wing, same angle of attack, the same wind speed, I have a force of 14N.

Does anyone know where the problem might come from? what I did wrong?

Thanks in advance

2

Hello

can you post an image of the result (top view and side view laminar direction) and also give us the parameters used

Kind regards

3

Good evening

Enclosed is the requested information .

Thank you for your responsiveness.

Cdt


doc_simulation_aile.docx
4

Hello zozo_mp,

 

Have you been able to see the requested information in the doc in the PJ?

 

Cdt

5

Hello

I looked and I'm reposting you the comment of @Nibblerg

(( look at the mesh. I tried with more than 1 million stitches (116,000 in your calculation) and there, the force following X is 0.16 N

With 2 million meshes, X = 0.08 N.  In my experience, the mesh is very important with flow, you should not hesitate to do several calculations, more and more meshed, until the results stabilize.""

I add to the suggestion of @Nibblerg to look at the number of nozzles (pick points) and therefore also the number of particles per nozzle. See your profile that looks symmetrical, which is not the case with a wing. also the sides are open so turbulence. Also look at the size of the volume that surrounds it (transparent box). Remember that planes at high altitude compensate for the lack of particles (play on lift) with speed, which produces more particle for lift. If small wing and low speed then  = iron.

Kind regards

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