[x31fighter]

I been trying to simulate the flow over E193 airfoil, and I get a Cl that resembles lab data. The drag coefficient doesn't come anywhere close to the data I am looking for. I am guessing it is an issue with the monitor, but I am not sure.

Also, I was wondering what data forces should I export from FLUENT to calculate the drag coefficient myself.

Thanks in advance!

[Manathan]

you should check your reference values you put; especially the "length" for 2D airfoil, it should be the chord. check also the density and the velocity.

[x31fighter]

Okay. I changed the reference values to the length of the airfoil and adjusted the velocity to what I had put in for the inlet. I actually got better number now, but the numbers are still too small to be compared to the published data. Would it be that I took the wrong measurement of one of the values?

[Manathan]

what about the density ? did you put the right density in the reference values, the one you used as pressure outlet conditions?

[x31fighter]

I kept the density the same as the fluid material. Was there something I had to specifically define in the boundary condition for outlet pressure?

[Hybrid]

Post your results and simulation setup.

[x31fighter]

For Cl I get -0.00236 and for Cd I get 0.1936. For zero angle of attack, I was expecting for Cl to be closer to 0.3.

The setup:
Model - Standard k-e, Standard, Wall Fn
Inlet Velocity - 2.88
Reference Values
http://i62.tinypic.com/qy9to1.png

The airfoil is 3D with a cord length of 0.3048 m with an extrusion of 0.3048 m.

Solution Method is simple with second order upwind set for turbulent kinetic energy, momentum and turbulent dissipation rate.

Solution controls are defaults and so are the monitors for Cd and Cl.

If you need anymore information, I can provide it. Thanks for the help.

[Hybrid]

Airfoil is symmetric? The simulation setup looks perfect.

[x31fighter]

Yep. It's this extruded by the mentioned distance.
http://recumbents.com/wisil/hpb/prop/e193.gif

[Hybrid]

Send me fluent case file...

[Hybrid]

Any success?

[x31fighter]

I am getting better numbers. If I kept the enclosure the same size, I get values that are only 30% off. Then if I increase the enclosure, the numbers got smaller.

What you suggested did help a lot, I am not getting close enough values within like 10-15%. :/