Study about influence of wing-mounted engine nacelle on high-lift system and improvement measures

By numerical simulation and wind tunnel experiment data, the influence of wing-mounted engine nacelle on high-lift system and the effects of nacelle stake setting at different positions have been investigated. The results indicated that: the separation flow from engine nacelle at high angles of attack and the slat cut-off have serious influence on aerodynamic characteristic of high-lift system. They caused a very large space of low-speed area above main wing and flap. An engine nacelle strake could improve this situation by setting at proper position. The mechanism is: a strong vortex would caused by nacelle strake at high angle of attack, then the vortex transport energy from freedom flow to the low-speed flow space. And the vortex would induce the low-speed to flow faster. Finally, the low-speed flow space reduced. But the position of nacelle strake need to optimize, setting it at unsuitable position will cause more lost of maximum lift.