Feasibility Study on Real-time Observation of Flow Velocity Field using Sparse Processing Particle Image Velocimetry
Feasibility Study on Real-time Observation of Flow Velocity Field using Sparse Processing Particle Image Velocimetry
复制标题
稀疏处理粒子图像测速实时观测流速场的可行性研究
DOI：
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发表时间：
2021
影响因子：
1.1
通讯作者：
K. Asai
中科院分区：
文献类型：
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作者：
Naoki Kanda;Kumi Nakai;Y. Saito;T. Nonomura;K. Asai
诸如使用等离子体致动器的主动流动控制已经引起了很多关注。实验和数值模拟研究了其在流动分离控制中的有效性。1）然而，由于缺乏流动控制效果，在高速气流中的能力受到限制。2）由于流动现象的复杂性和非线性，基于全状态或全局流动信息而不是局部流动信息的反馈控制显然更适合于未来的流动反馈控制。粒子图像测速技术（PIV）在实验室测量中提供了瞬时速度场，可用于近全状态的观测。因此，流场的实时PIV测量似乎是流动控制的有力工具。在PIV测量过程中，从粒子图像的每个询问窗口的互相关系数计算速度场，但是可以在短时间内处理的窗口的数量是有限的。这是因为实时PIV测量应用于气动流动控制实验时，PIV计算时间太长，而气动流动控制实验的时间尺度比水动力实验短。在这项研究中，降阶建模，并考虑减少计算时间。提出了稀疏处理PIV（SPPIV）方法来实现实时的近全状态估计。对NACA0015翼型模型绕流场进行了PIV测量，并对SPPIV测量结果和处理时间进行了评价。
Active flow control such as the use of a plasma actuator has been gathering much attention. Its effectiveness in flow separation control has been investigated experimentally and numerically.1) However, the capability during highspeed airflow is limited due to the lack of the flow control effect. Hence, feedback control utilizing the real-time measurement of the flow state is expected to improve applicability.2) Because of the complexity and nonlinearity of the flow phenomena, feedback control based on not the local flow information, but the full-state or global flow information clearly appears to be better for the future feedback control of flows. The use of particle image velocimetry (PIV), which provides the instantaneous velocity field in laboratory measurement can be used for nearly full-state observation. Therefore, real-time PIV measurement of the flow field seems to be a powerful tool for flow control. The velocity field is calculated from the cross-correlation coefficient for each interrogation window of the particle images during the PIV measurement, but the number of windows that can be processed in a short duration is limited. This is because the PIV computational time is too long when real-time PIV measurement is applied to aerodynamic flow-control experiments, which have a shorter time scale than hydrodynamic experiments. In this study, reduced-order modeling is employed and reducing the calculation time is considered. The authors proposed sparse processing PIV (SPPIV) as a method to achieve the real-time nearly full-state estimation. The PIV measurement of the flow field around a NACA0015 airfoil model was conducted and the flow field obtained using SPPIV and the processing time were evaluated.