矩形断面抖振阻力空间分布特性试验研究

发布时间：2018-06-02 02:53

本文选题：抖振阻力 + 跨向相关性　；参考：《工程力学》2017年01期

【摘要】：为了研究紊流作用下钝体抖振阻力的空间分布特性及流固相互作用机理,以2∶1矩形断面为例,通过刚性模型测压试验研究了抖振阻力的跨向相关性及空间能量分布特性。结果表明,当紊流积分尺度与钝体特征尺寸相当时,抖振阻力的相关性高于纵向脉动风,这也许是由漩涡沿展向发生拉伸引起。而在分离点附近,来流漩涡会发生剧烈畸变,顺流向大尺度漩涡会破碎成小尺度漩涡,在此过程中能量由低频向高频的转移,并导致脉动压力的跨向相关性也会有所减弱。与迎风侧不同,背风侧脉动压力主要受钝体尾流中的紊流成分影响,其漩涡沿跨向拉伸程度可能要高于迎风侧,以致背风侧脉动压力的跨向相关性强于迎风侧。顺流向分离涡在由分离点向中部运动过程中,其高频的小尺度漩涡可能并没沿顺流向拉伸,而是直接耗散,从而导致脉动压力谱在低频保持不变,而在高频区下降。
[Abstract]:In order to study the spatial distribution characteristics and the interaction mechanism of the blunt body buffeting resistance under turbulent flow, the cross correlation and spatial energy distribution characteristics of the buffeting resistance are studied by the rigid model pressure test, taking the 2: 1 rectangular section for example. The results show that the buffeting resistance when the turbulence integral scale is equivalent to the characteristic size of the blunt body. The correlation is higher than the longitudinal pulsating wind, which may be caused by the vortex stretching along the spreading direction. In the vicinity of the separation point, the vortex will be distorted and the vortex will break into a small vortex. In this process, the energy is transferred from low frequency to high frequency, and the cross correlation of the pulsating pressure will be weakened. On the windward side, the fluctuating pressure of the leeward side is mainly influenced by the turbulent flow in the wake of the blunt body, and the whirlpool may be higher than the upwind side along the cross direction, so that the cross correlation of the fluctuating pressure on the leeward side is stronger than the upwind side. Instead of direct flow, it is directly dissipated, resulting in fluctuating pressure spectrum unchanged at low frequency and decreasing at high frequency.
【作者单位】：重庆大学土木工程学院;西南交通大学风工程试验研究中心;风工程四川省重点实验室;
【基金】：国家自然科学基金项目(51278435,51478402,51408505) 中央高校基本科研业务费专项资金科技创新项目(2682014CX069)
【分类号】：U441.3

【相似文献】