Study on three-dimensional flow structures of a sweeping jet using time-resolved stereo particle image velocimetry
Study on three-dimensional flow structures of a sweeping jet using time-resolved stereo particle image velocimetry
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时间分辨立体粒子图像测速研究扫掠射流三维流动结构
DOI：
10.1016/j.expthermflusci.2019.109945
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发表时间：
2020
影响因子：
3.2
通讯作者：
Kim Kyung Chun
中科院分区：
文献类型：
--
作者：
Wen Xin;Liu Jiajun;Kim Donguk;Liu Yingzheng;Kim Kyung Chun
采用立体和二维PIV(粒子图像测速仪)测量方法，对扫射致动器向开阔空间发射的扫射诱导的三维流动结构进行了实验研究。提出了一种新的基于本征正交分解的相平均流场计算方法，该方法比已有的方法对局部流动波动具有更强的鲁棒性。射流雷诺数(Re)固定为8000，射流出口为方形，水力直径(Dh)为10 mm。首先利用不同平面上的多个二维流场重建了扫掠射流的三维时均流场。在时均流场中，射流分布一般呈V形，由两个倾斜的射流柱组成，射流的倾角约为90°。当射流离开射流出口时，由于射流出口的约束作用，射流柱的形状也由椭圆形变为圆形。然后在距离喷口8Dhaway的两个横截面上进行了立体声PIV测量。在距喷流出口3Dh的平面内，当喷流从一侧掠过到另一侧时，在切换期间形成了一对反向旋转的旋涡。这是因为射流的切换运动可以增强射流的剪切层，就像横流中的射流一样。另一方面，在距喷流出口8d的平面上，由于强烈的湍流和弱的切换运动，对旋涡迅速消散。
The three-dimensional flow structures that were induced by a sweeping jet emitted from a sweeping jet actuator to an open space were examined experimentally using stereo and two-dimensional PIV (particle image velocimetry) measurements. A new method was proposed to obtain phase-averaged flow field based on proper orthogonal decomposition, which is more robust to local flow fluctuations than existing methods. The jet Reynolds number (Re) was fixed to 8000 and the jet exit had a square shape with a hydraulic diameter (Dh) of 10 mm. The three-dimensional time-averaged flow fields of the sweeping jet were first reconstructed using multiple two-dimensional flow fields along various planes. In the time-averaged flow field, the jet flow distribution generally showed a V-shape pattern, which consisted of two inclined jet columns with an angle of approximately 90°. As the jet traveled away from the jet exit, the shape of jet column also changed from an elliptical shape to a circular shape because of the confinement effect of the jet exit. Stereo-PIV measurements were then conducted at two cross-sectional planes with distances of 3Dhand 8Dhaway from the jet exit. In the plane 3Dhfrom the jet exit, one pair of counter-rotating vortices formed during the switching period when the jet swept from one side to the other. This is because the jet switching motion can enhance the jet shear layer, as in the case of a jet in crossflow. On the other hand, on the plane 8Dhaway from the jet exit, the counter-rotating vortices dissipated quickly owing to the strong turbulence and weak switching motion.
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影响因子：
4.6
作者：
X. Wen;Hui Tang;F. Duan
通讯作者：
X. Wen;Hui Tang;F. Duan
影响因子：
4.6
作者：
X. Wen;Ziyan Li;D. Peng;Wenwu Zhou;Yingzheng Liu
通讯作者：
X. Wen;Ziyan Li;D. Peng;Wenwu Zhou;Yingzheng Liu
影响因子：
1.1
作者：
K. Chu
通讯作者：
K. Chu
DOI：
10.1016/j.ijheatmasstransfer.2018.04.016
发表时间：
2018-09
影响因子：
5.2
作者：
Tongil Park;Kursat Kara;Daegyoum Kim
通讯作者：
Tongil Park;Kursat Kara;Daegyoum Kim
DOI：
10.2514/6.2015-0781
发表时间：
2015-01
期刊：
--
影响因子：
--
作者：
Florian Ostermann;R. Woszidlo;C. Nayeri;C. Paschereit
通讯作者：
Florian Ostermann;R. Woszidlo;C. Nayeri;C. Paschereit