High drag coeff. estimated by Gambit+fluent

M. suuri

I am using gambit grid generator and fluent as solver to simulate flow over a low Re. number airfoil (150,000 to 700,000). I have used BL. while mesh generation. (I donot bay attantion to y+!!).

I used k_omega and k_epsilon modles with diffrent combinations of options.

results were compared to both (1)old german wind tunnel data and also to (2) 2004 wind tunnel data.

Lift coeff. results were between the two exp. results. Drag and pithcing momnet coeff.s show high errors(difrences)

Drag coeff. for example has about 50% error with both exp. results.

Can I get explantion or advise to modify my solver or grid generator configurations.

M. Surri