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The prerequisite for accurate prediction and effective control of flow phenomena fundamentally lies in the understanding of flow dynamics, and experimental studies provide essential data to support this process. Particle image velocimetry (PIV), as one of the important methods for flow field measurement, plays a critical role in experimental investigations such as flow past a circular cylinder. PIV is a non-contact laser-optical measurement technique; however, it often faces challenges in obtaining complete and accurate flow field data when the optical path is obstructed. Particularly in PIV experiments involving flow past a circular cylinder, the presence of the cylinder itself and the supporting structure can significantly obscure the optical path, making it highly challenging to acquire complete PIV data. To address this issue, we propose a deep learning-based flow field data reconstruction method, which employs a deep learning framework centered on convolutional neural networks (CNNs). The method aims to solve the reconstruction problem of gappy regions in flow field data by establishing a mapping relationship between flow fields with gappy regions and complete flow fields. First, the influence of gappy regions with different characteristics on the reconstruction accuracy of numerically simulated flow fields is investigated. The reconstructed flow fields are carefully compared and analyzed against ground truth data across multiple dimensions, including instantaneous flow fields and velocity time statistics. The results indicate that the maximum $L_2$ error between the reconstructed flow field and the ground truth remains at approximately 0.02. Furthermore, it is observed that as the size of the gappy region along the flow direction increases, the difficulty of flow field reconstruction increases significantly. In contrast, changes in the size of the gappy region perpendicular to the flow direction have minimal impact on the accuracy of flow field reconstruction. Additionally, the robustness of the proposed deep neural network to noise is systematically evaluated. While clean numerical simulation data are used for training, test data are generated by artificially introducing varying levels of Gaussian noise to assess the network's performance under noisy conditions. The results demonstrate that the error between the reconstructed data and the ground truth increases exponentially as the noise level rises. Finally, the proposed deep neural network model is applied to real PIV experimental data, with the training data remaining clean and numerically simulated. Both instantaneous flow fields and time-averaged statistics are analyzed and compared. The results reveal that the network model successfully reconstructs velocity information in the missing regions and effectively corrects data errors caused by measurement inaccuracies in the backflow zones. The reconstructed experimental results show closer statistical agreement with numerical simulation data, demonstrating that the model proposed in this paper, when trained solely on numerical simulation data, is capable of reconstructing missing physical information in PIV experiments. This approach provides a novel methodology for addressing data reconstruction challenges in PIV experiments.
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Keywords:
- Deep learning /
- Gappy data /
- Flow past a circular cylinder
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[1] Ragni D, Van O B W, Scarano F 2010 Meas. Sci. Technol. 22 017003
[2] Gunes H, Rist U 2008 Phys. Fluids 20 104109
[3] Tan B T, Damodaran M, Willcox K E 2004 AIAA J. 42 1505
[4] Li T Y, Buzzicotti M, Biferale L, Wang M P, Chen S Y 2021 Chin. J. Mech. 53 2703-2711(in Chinese)[李天一, Buzzicotti Michele, Biferale Luca,万敏平,陈十一2021力学学报53 2703- 2711]
[5] Sciacchitano A, Dwight R P, Scarano F 2012 Exp. Fluids 53 1421
[6] Zimmermann R, Vendl A 2014 AIAA J. 52 255
[7] Ruscher C J, Dannenhoffer J F, Glauser M N 2017 AIAA J. 55 255
[8] Deng Z W, He C X, Wen X, Liu Y Z 2018 J. Vis. 21 1043
[9] Li T X, He C X, Wen X, Liu Y Z 2023 J. Vis. 26 815
[10] He C X, Deng Z W, Liu Y Z 2021 Acta Aeronautica et Astronautica Sinica 42 167(in Chinese)[何 创新,邓志文,刘应征2021航空学报42 167]
[11] Yuan H, Kou J Q, Zhang W W 2024 Chin. J. Mech. 56 2799(in Chinese)[袁昊,寇家庆,张伟伟 2024力学学报56 2799]
[12] Zhang W W, Wang X, Kou J Q 2023 Adv. Mech. 53 433-467(in Chinese)[张伟伟,王旭,寇家庆 2023力学进展53 433-467]
[13] Ren F, Gao C Q, Tang H 2021 Acta Aeronautica et Astronautica Sinica 42 524686(in Chinese)[任 峰,高传强,唐辉2021航空学报42 524686]
[14] Vinuesa R, Brunton S L, McKeon B J 2023 Nat. Rev. Phys 5 536
[15] Brunton S L 2021 Acta Mech. Sin. 37 1718
[16] Wen Z K, Shu W P, Zhang H, Liu S B, Zhang L Q, Liu L, Wang T, Zhang Q J, Li S 2024 Space Sci. Technol. 4 0080
[17] Xv Q W, Wang P P, Zeng Z J, Huang Z B, Zhou X X, Liu J M, Li Y, Chen S Q, Fan D Y 2020 Acta Phys. Sin. 69 204701(in Chinese)[徐启伟,王佩佩,曾镇佳,黄泽斌,周新星,刘俊敏,李瑛,陈 书青,范滇元2020 69 204701]
[18] Zheng J Y, Wang S Y, Wang G X, Deng X G 2020 Acta Phys. Sin. 69 204701(in Chinese)[郑天 韵,王圣业,王光学,邓小刚2020 69 204701]
[19] Wang H P, Yang Z X, Li B L, Wang S Z 2020 Phys. Fluids 32 115105
[20] Morimoto M, Fuakmi K, Fukagata K 2021 Phys. Fluids 33 087121
[21] Zhang F, Hu H B, Ren F, Zhang H, Du P 2022 Phys. Fluids 34 127117
[22] Luo Z H, Wang L Y, Xu J, Wang Z L, Chen M, Yuan J P 2023 Phys. Fluids 35 085115
[23] Luo Z H, Wang L Y, Xu J, Yuan J P, Chen M, Li Y, Andy C T 2024 Ocean Eng. 293 116605
[24] Zheng Q M, Li T Y, Ma B T, Fu L, Li X M 2024 Phys. Rev. Fluids 9 024608
[25] Muharrem H A, Ilker G, Murat I, Abdullah C 2023 Phys. Fluids 35 114110
[26] He K M, Zhang X Y, Ren S Q, Sun J 2016 ICCV Santiago, Chile, December 13-16, 2015 p1026
[27] Zhang F, Hu H B, Zhang H, Zhang M, Song J, Meng Y Z 2024 Ocean Eng. 309 118578
[28] Szegedy C, Ioffe S, Vanhoucke V, Alemi A 2017 AAAI California, USA, Feb 4-9, 2017 Vol. 31,(1)
[29] Lin M 2013 arxiv preprint arxiv 1312 4400
[30] He K M, Zhang X Y, Ren S Q, Sun J 2016 CVPR Las Vegas, USA, June 26-July 1, 2016 p770
[31] Taira K, Hemati M S, Brunton S L, Sun Y Y, Duraisamy K, Bagheri S, Dawson S T M, Yeh C A 2020 AIAA J. 58 998
[32] Chen J L, Ding H Y, Hu H B, Zhang F, Wen J 2024 Experimental Fluid Mechanics 39 http://kns.cnki.net/kcms/detail/11.5266.V.20241022.1005.002.html.(in Chinese)[陈蒋力,丁海艳, 胡海豹,张帆,文俊2024实验流体力学39]
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