Modeling of vortex‐corner interaction using point vortices
Modeling of vortex‐corner interaction using point vortices
复制标题
使用点涡对涡角相互作用进行建模
DOI：
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发表时间：
1981
期刊：
影响因子：
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通讯作者：
D. Rockwell
中科院分区：
文献类型：
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作者：
A. Conlisk;D. Rockwell
利用点涡，研究了单个涡以及涡型与转角的相互作用，并与相应的实验进行了比较。如果指定了足够弱的涡旋强度，则可以很好地近似计算掠过拐角的涡旋的轨迹。计算表明，转角处压力脉动的无量纲振幅对涡旋初始位置的微小变化非常敏感，而对强度的变化相对不敏感；这一发现对最近观测到的撞击处压力和附近速度的振幅调制具有重要的意义。事实上，通过规定由实验流动显示确定的拐角上游横向交错的旋涡模式，可以近似得到时间平均压力谱和速度谱的形式。这些光谱中最关键的特征是一个定义明确的低频成分(S)，它证实了与实验中观察到的低频调制有关的假设机制。此外，还指出了这种方法的不足之处，主要是由于实验室涡旋固有的分布涡量。
Using point vortices, the interaction of a single vortex, as well as patterns of vortices, with a corner is examined; comparisons are made with corresponding experiments. Trajectories of a vortex swept past the corner can be well‐approximated, provided that a sufficiently weak strength of the vortex is specified. Calculations show that the dimensionless amplitude of the pressure fluctuation at the corner is very sensitive to small variations of the initial position of the vortex, and relatively insensitive to variations in strength; this finding has important consequences for recently observed amplitude modulation of pressure at, and velocity near, impingement. In fact, by prescribing transversely staggered patterns of vortices upstream of the corner, determined from experimental flow visualization, the form of the time‐averaged pressure and velocity spectra can be approximated. The most critical feature of these spectra, a well‐defined low‐frequency component(s), confirms the hypothesized mechanism associated with low‐frequency modulation observed in experiments. In addition, shortcomings of this method, primarily due to distributed vorticity inherent in laboratory vortices, are pointed out.