上游靜止柱體下仿生機器魚自主游動的數值模擬

NUMERICAL SIMULATION OF SELF-PROPELLED SWIMMING OF BIONIC FISH BEHIND AN UPSTREAM STATIONARY COLUMN

黃技(Ji Huang) ； 王成彥(Cheng-yan Wang) ； 紀然(Ran Ji) ； 李佳文(Jia-Wen Li)

《中國土木水利工程學刊》 35卷1期 (2023/03) Pp. 1-9

https://doi.org/10.6652/JoCICHE.202303_35(1).0001

摘要

本文研究了靜止柱體脫落的漩渦對仿生機器魚推進性能的影響。基於計算流體力學方法，採用SST k-ω湍流模型使雷諾平均方程式（RANS）封閉，使用C語言程序進行二次開發，處理機器魚游動時之流固耦合計算。數值結果表明：隨著擺尾頻率的增加，機器魚所獲得的推力與付出的能耗也將增加，推進效率呈現出逐步下降的趨勢。上游柱體脫落的尾渦將使機器魚獲得更大幅值的推力。在本研究的案例中，機器魚在渦流場内將付出更多額外的功而造成節能效率下降。同時，上游柱體脫落的尾渦將擠壓下游魚尾部擺動產生的渦街，導致下游的渦街產生偏斜。渦街的偏斜意味著機器魚推進時尾跡中射流的方向將發生改變。

關鍵字

仿生機器魚 ； 渦流場 ； 自主推進 ； 流固耦合

並列摘要

In this work, the effect of vortices shed by a stationary column on the propulsive performance of a bionic machine fish is investigated. Based on the computational fluid dynamics method, the SST k-ω turbulence model is used to make the Reynolds-Averaged Navier-Stokes equations (RANS) closed, and the C language is used for the secondary development to deal with the fluid-structure interaction calculation when the machine fish swims. The numerical results show that as the frequency of tail swing increases, the thrust obtained by the machine fish and the energy cost will also increase, and the propulsion efficiency shows a gradual decrease. The tail vortex shed by the upstream column will allow the machine fish to obtain a larger magnitude of thrust. In the case of this study, the machine fish will pay more extra work in the vortex field and cause the energy saving efficiency to decrease. Meanwhile, the tail vortex shed by the upstream column will squeeze the vortex street generated by the tail oscillation of the downstream fish, resulting in the deflection of the vortex street downstream. The deflection of the vortex street means that the direction of the jet in the wake will change as the machine fish advances.

並列關鍵字

bionic machine fish ； vortex field ； self-propelled ； fluid-structure interaction

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