Abstract
In this study, the optical flow method for the skin-friction-stress estimation from the unsteady oil film distribution was reformulated based on the variational method, and the validity of the proposed method was verified in comparison with the conventional method. The regularization is proposed to be added directly to the skin-friction-stress field in the proposed method while the regularization is added to the amount of oil movement in the conventional method. As a result, the smoothness of the skin-friction-stress field can be controlled by adjusting the regularization parameter in the proposed method whereas it was difficult in the conventional method. The performance of the proposed method was evaluated to be superior to the previous method through the numerical and experimental data.
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Acknowledgements
This work was partially supported by JSPS KAKENHI Grant Number 20H00278 and 19KK0361, and JST FOREST Grant Number JPMJFR202C.
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Endo, K., Ambo, T., Saito, Y. et al. Proposal and verification of optical flow reformulation based on variational method for skin-friction-stress field estimation from unsteady oil film distribution. J Vis 25, 263–280 (2022). https://doi.org/10.1007/s12650-021-00794-8
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DOI: https://doi.org/10.1007/s12650-021-00794-8