翼吊发动机短舱对三维增升装置的影响及改善措施研究

运用数值模拟方法,结合风洞试验数据,研究了翼吊发动机短舱对于增升装置气动性能的影响以及在发动机短舱的不同位置安装涡流片进行流动控制的效果.结果表明:翼吊发动机短舱挂架与机翼前缘结合处的缝翼缺口及大迎角时绕过短舱的分离气流会对三维增升装置造成不利影响,其主要表现为在主翼上方形成一个很大范围的低速流动区.在发动机短舱适当位置安装涡流片能明显改善增升装置的气动性能.主要机理在于:涡流片在大迎角时产生的强漩涡能向低速区内注入能量,搅动该区域的流动,从而减小低速流动区的范围.但是涡流片的位置必须进行优化,在不适当的位置安装涡流片会进一步恶化增升装置的气动性能.

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.