20°圆锥分离流动的发展特性  

Exploring Cause of Asymmetric Vortex Flow over Slender Circular Cone at High Angle of Attack

作　　者：盂宣市[1] 乔志德[1] 高超[1] 罗时钧[2] 刘锋[2] 

机构地区：[1]西北工业大学翼型叶栅国防科技重点实验室,陕西西安710072 [2]美国加州大学尔湾分校机械与宇航工程系,92697-3975

出　　处：《西北工业大学学报》2010年第5期655-659,共5页Journal of Northwestern Polytechnical University

基　　金：高等学校博士学位点专项科研基金(SRFDP-20096102120001、200806990003);西北工业大学基础研究基金(JC200901);中国博士后科学基金(20100471000)资助

摘　　要：文章对20°顶角的圆锥-圆柱组合体在3.0×1.6 m低速低湍流度风洞进行了表面压力分布测量和二维粒子图像测速。基于圆锥底面直径的雷诺数0.3×106,迎角0°-35,°包含40个滚转角,以9°为等间隔,滚转角范围0°-351°。文中主要分析了不同迎角下,圆锥段9个测量截面上的压力分布以及积分得到的截面当地侧向力随滚转角的变化特性,由压力分布对测量截面的流动分离状态进行了推断,推断结果与二维粒子图像测速实验进行了比较。结果表明：迎角从0°增大到35°的过程中,当地侧力系数随滚转角的变化曲线分别呈现：①零值线;②连续波曲线;③方波曲线。当侧力系数变化呈现连续波曲线和方波曲线时,所有测量截面上波曲线的周期和相位都近似相同。圆锥上非对称力的产生和发展是由于分离涡的不稳定性造成的。Aim.The introduction of the full paper points out that the mechanism underlying asymmetric vortex shedding from axisymmetric slender bodies is as yet not clear.In our exploratory experimental study,we analyze test results and attempt to shed some light on asymmetric vortex flow.We explain our exploratory study in sections 1,2 and 3.The core of sections 1 and 2 consists of：（1）we perform the pressure measurement of a 20° circular cone cylinder model in the low-turbulence 3.0m×1.6m low-speed wind tunnel at the angle of attack of 0°-35 °;（2） the Reynolds number calculated by using the base diameter of the circular cone is 0.3 million;（3） the measurement tests encompass 40 rolling angles（0°～351°） at 9 interval;（4） from the measured pressures,we calculate the pressure distributions over nine stations along the circular cone at all angles of attack and the local side force over the circular cone.The core of section 3 consists of：（1） from the measured pressures,we infer and verify the primary state of the boundary layer by performing PIV（particle image velocimetry） tests;（2） the test results indicate that as the angle of attack increases,the local side force coefficient versus rolling angle develops in three stages： zero curve,continuous-wave curve and square-wave curve;（3） the period and phase of the wave curves are the same for all instrumented stations at all angles of attack;（4） the cause of the wavy variation of the local side force versus rolling angle is identified as instability of the vortex flow shedding from the cone surface.

关 键 词：粒子图像测速 涡的稳定性 大迎角空气动力 细长圆锥 非对称分离涡 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程]