Minimal improved far field method for airfoil drag evaluation——wake integration method was introduced. The position of wake integration and associated integral technics were also discussed. Predicted drag values for a given airfoil(RAE2822 airfoil)were compared and discussed using the surface integration and wake integration methods under both subsonic and supercritical flow conditions. Numerical data show that the results of both methods are the same, which indicates the wake surface integration method is valid. The calculated values agree well with the experimental data. It also indicate that in the wake integration method, the location of wake integration surface should be set in the distance of 0.6~1.0 relative chord length from the trailing edge. In the mean time, the results of wake integration method is independent of the variation of detailed configuration surface. Wake integration method might be more potential for the complex three-dimensional configurations having large curvature variation on the surface compared with surface integration method.
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