基于层析PIV的湍流边界层展向涡研究

发布时间：2018-02-26 10:02

本文关键词： 层析粒子图像测速湍流边界层旋涡识别展向涡　出处：《实验流体力学》2016年02期 　论文类型：期刊论文

【摘要】：层析PIV是一种现代激光测速技术,能实现三分量空间体内三分量(3D3C)速度场的测量。应用层析PIV测量Re_τ=1768的平板湍流边界层,得到150个瞬时速度场,测量体的大小为80mm×16mm×45mm。旋涡强度λ_(ci)准则用来进行涡识别,而旋涡强度在展向的投影λ~z_(ci)被用来识别展向涡。根据λ~z_(ci)的连通域得到展向涡位置后,统计了展向涡沿法向的变化规律,并给出了在流向-法向平面内高低速区域和正负展向涡空间位置的关系。统计结果表明:随着法向高度的增加,展向涡的强度逐渐降低;负展向涡的流向平均速度高于正展向涡,且流向速度与法向速度有很强的依赖性;在小尺度范围内,流向-法向平面内的高低速流动区域与正负展向涡的空间位置密切相关。
[Abstract]:Tomographic PIV is a modern laser velocimetry technique, which can measure the velocity field of three components in three component space. The turbulent boundary layer of Re蟿 1768 has been measured by PIV chromatography, and 150 instantaneous velocity fields have been obtained. The size of the measured body is 80mm 脳 16mm 脳 45mm. the vortex intensity 位 _ (cicic) criterion is used for vortex identification, while the vortex intensity is used to identify the spanned vortex in the projection 位 ~ (+ +) of the vortex. The variation of the vortex along the normal direction is calculated according to the location of the spanned vortex in the connected domain. The relationship between the high and low velocity region and the spatial position of the positive and negative spanwise vortices in the fluid-normal plane is given. The statistical results show that the strength of the vortex decreases with the increase of the normal height. The average velocity of the negative vortex is higher than that of the positive vortex, and the velocity of the flow direction is strongly dependent on the normal velocity, and in a small scale, the high and low velocity flow region in the fluid-normal plane is closely related to the spatial position of the positive and negative spanwise vortices.
【作者单位】：北京航空航天大学流体力学研究所流体力学教育部重点实验室;北京立方天地科技有限责任公司;
【基金】：国家自然科学基金(11472030,11327202,11490552)
【分类号】：O357.5

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