Numerical Investigation of Noise Reduction Effects of Slat Cusp Sawtooth and Slat Cusp Extension

Slat cusp sawtooth and slat cusp extension are both potential small-size low noise devices on slat cusp, which have advantages of compatibility on certification rules and sturcture designs. By using the DES/FW-H hybrid simulation of the commercial code ANSYS FLUENT, the noise reduction performance of slat cusp sawtooth and slat cusp extension are investigated. Transient flow field results show that compared to slat cusp baseline, slat cusp sawtooth always brings higher or same level of pressure fluctuations, while slat cusp extension always keeps same or lower level of pressure fluctuations. Far field noise results show that compared to slat cusp baseline, slat cusp extension has a notable noise reduction performance, while slat cusp sawtooth has almost no noise reduction effect for directions to earth.