High-lift devices are commonly modeled with potential flow methods at the conceptual design stage. Often, these analyses require the use of prescribed wake shapes, however, the wake type used will have an impact on the results. A study was completed which compared the predicted aerodynamic performance of slotted high-lift devices modeled using different wake types. Lift and induced drag results are compared when using relaxed wakes, freestream fixed wakes, and wakes prescribed above and below the freestream direction. Analysis of the predicted induced drag values show that a relaxed wake model predicts experimental data the closest, however, if accuracy can be reduced in favor of a faster solution, a drag free wake or a wake prescribed to angles within 10 degrees of the freestream direction can be used with little reduction in accuracy. The predicted lift curves found with relaxed wakes were also the closest to experimental data, and it was found that lift curve slopes differ as different wake types are used. At a given angle of attack, lift coefficients will deviate approximately 2.7% for every ten degree difference between the prescribed wake angle and the freestream direction. This correction factor can be applied to results found with prescribed wake shapes to generate values which show good agreement to experimental data.
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