火箭发射燃气流噪声孔隙效应数值模拟研究  

Numerical Simulation of Hole Clearance Effect of Rocket Launch Jetflow Noise

作　　者：陈劲松[1] 曾玲芳[1] 吴新跃[1] 王南[1] 李晓凉 Chen Jin-song;Zeng Ling-fang;Wu Xin-yue;Wang Nan;Li Xiao-liang(Beijing Institute of Space Launch Technnogy,Beijing,100076)

机构地区：[1]北京航天发射技术研究所,北京100076

出　　处：《导弹与航天运载技术》2020年第4期91-95,共5页Missiles and Space Vehicles

基　　金：国家自然科学基金(51741602)。

摘　　要：针对火箭点火起飞阶段发射平台附近燃气流噪声孔隙效应,综合有限体积法和伽辽金有限元法数值模拟研究了该效应特性及其机理。数值模拟研究发现,火箭发射初期,发射平台结构屏蔽作用突出,燃气流噪声主要经发射平台与场坪间隙向周围透射;发射平台结构跨度较小时,这部分透射噪声将向台体上方衍射,对箭体产生影响。当箭体与发射平台之间存在安装高度间隙时,衍射噪声会经高度间隙直接向箭体衍射,并且衍射噪声强度随高度间隙增加而增加。发射平台导流孔入口也可形成直接向箭体衍射的燃气流噪声,但情况相对特殊,当发射平台导流孔直径大于喷口直径时,衍射噪声比较明显,发射平台导流孔孔径越大,衍射燃气流噪声也越强;发射平台导流孔直径小于喷口直径时,经发射平台反溅的燃气流形成的反射噪声占据主要地位,衍射噪声淹没于反射噪声环境。The finite volume method and Galerkin finite element method are used to simulate the hole clearance effect of jetflow noise near the launch platform during the rocket taking off. The study finds that in the early stage of rocket launch, the shielding effect of the launch platform structure is outstanding, and the jetflow noise is transmitted mainly through the gap between the launch platform and the ground. As the span of the transmitting platform structure is relatively small, this part of the transmitted noise will be diffracted to the upper part of the platform and affect the rocket body. While there is a installation height gap between the rocket body and the launch platform, the row emission noise will diffract directly to the body of the rocket through the height gap, and the intensity of the row emission noise increases with the increase of the height gap. However, the situation is relatively special. When the launch platform diversion hole diameter is larger than the nozzle diameter, the direct emission noise is obvious. The higher the aperture of the launch platform diversion hole, the stronger the noise of jetflow. When the launch platform diversion hole diameter is smaller than that of the nozzle, the reflected noise formed by the jetflow that is splashed back from the transmitting platform occupies the main position, and the diffraction noise id drowned in the environment of the reflecting noise.

关 键 词：孔隙效应 燃气流噪声 燃气流噪声数值模拟 高阶伽辽金有限元法 发射平台 

分 类 号：V411[航空宇航科学与技术—航空宇航推进理论与工程]