Abstract Periodic vortex shedding which forms when fluid moves over a circular cylinder creates a wake which causes fluctuating unsteady forces on structures. The oscillating wake may also serve to enhance heat transfer rates from a surface on which it impinges. In this paper we investigate the passive excitation of the impinging jet's velocity field using a cylindrical insert. The insert is placed just before where the jet issues from the circular pipe. The flow is examined using Large Eddy Simulations (LES). The jet's Reynolds number based on bulk inlet velocity is 23,000 and jet's outlet-to-target wall distance is two. It is found that using a cylindrical insert in the impingement pipe results in enhanced heat transfer rates for cooling applications.

中文翻译：

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被动激发撞击射流的 LES 调查

摘要 流体在圆柱体上移动时形成的周期性涡旋脱落会产生尾流，从而在结构上产生波动的非定常力。振荡尾流还可用于提高其撞击表面的传热速率。在本文中，我们使用圆柱形插件研究了撞击射流速度场的被动激发。插入件刚好放置在射流从圆形管道发出的位置之前。使用大涡模拟 (LES) 检查流动。基于整体入口速度的射流雷诺数为 23,000，射流出口到目标壁的距离为 2。发现在冲击管中使用圆柱形插入件可提高冷却应用的传热率。