Abstract
Viewed as sinews and muscles of fluid motion, coherent vortical structures with their interactions are key to understanding the flow dynamics. Based upon this observation, we explore the possibility of efficient flow control by directly manipulating vortices numerically inside the flow field based on the vortex definition and identification system of Liutex. The objective is twofold: (1) to study the vortex dynamics, for example, by observing the response of the flow to strengthening or weakening of certain vortices, and (2) to obtain efficient vortex-based control strategies which might lead us to practical applications. In the present numerical study, the manipulating of vortices is achieved by introducing additional source (force) terms to the Navier-Stokes equations, which hereafter will be collectively called Liutex force field model. Methodologies including controlling the rotation strength and centripetal force of particular vortices are detailed in a flow past a cylinder with different control purposes at Reynolds number of 200. Further examples are provided with a cavitating flow around two-dimensional Clark-Y hydrofoil, with particular interests on cavitation suppression. It is illustrated particular vortex with cavitation encircled could be effectively suppressed.
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Luo X., Ji B., Tsujimoto Y. A review of cavitation in hydraulic machinery [J]. Journal of Hydrodynamics, 2016, 28(3): 335–358.
Huang B., Qiu S. C., Li X. B. et al. A review of transient flow structure and unsteady mechanism of cavitating flow [J]. Journal of Hydrodynamics, 2019, 31(3): 429–444.
Nakamura K., Kurosawa S. Design optimization of a high specific speed Francis turbine using multi-objective genetic algorithm [J]. International Journal of Fluid Machinery and Systems, 2009, 2(2): 102–109.
Enomoto Y., Kurosawa S., Kawajiri H. Design optimization of a high specific speed Francis turbine runner [J]. IOP Conference Series: Earth and Environmental Science, 2012, 15(3): 032010.
Che B., Chu N., Schmidt S. J. et al. Control effect of micro vortex generators on leading edge of attached cavitation [J]. Physics of Fluids, 2019, 31(4): 044102.
Che B., Chu N., Cao L. et al. Control effect of micro vortex generators on attached cavitation instability [J]. Physics of Fluids, 2019, 31(6): 064102.
Küchemann D. Report on the I.U.T.A.M. symposium on concentrated vortex motions in fluids [J]. Journal of Fluid Mechanics, 1965, 21(1): 1–20.
Liu C., Yan Y., Lu P. Physics of turbulence generation and sustenance in a boundary layer [J]. Computers and Fluids, 2014, 102: 353–384.
Liu C., Gao Y. S., Dong X. R. et al. Third generation of vortex identification methods: Omega and Liutex/Rortex based systems [J]. Journal of Hydrodynamics, 2019, 31(2): 205–223.
Robinson S. K. Coherent motion in the turbulent boundary layer [J]. Annual Review of Fluid Mechanics, 1991, 23: 601–639.
Wang Y., Yang Y., Yang G. et al. DNS study on vortex and vorticity in late boundary layer transition [J]. Communications in Computational Physics, 2017, 22(2): 441–459.
Hunt J., Wray A., Moin P. Eddies, streams, and convergence zones in turbulent flows [R]. Proceedings of the Summer Program. Center for Turbulence Research Report CTR-S88, 1988, 193–208.
Jeong J., Hussain F. On the identification of a vortex [J]. Journal of Fluid Mechanics, 1995, 285: 69–94.
Chong M. S., Perry A. E., Cantwell B. J. A general classification of three-dimensional flow fields [J]. Physics of Fluids A, 1990, 2(5): 765–777.
Zhou J., Adrian R., Balachandar S. et al. Mechanisms for generating coherent packets of hairpin vortices in channel flow [J]. Journal of Fluid Mechanics, 1999, 387: 252–296.
Liu C., Gao Y., Tian S. et al. Rortex-A new vortex vector definition and vorticity tensor and vector decompositions [J]. Physics of Fluids, 2018, 30(3): 034103.
Liu J., Gao Y., Liu C. An objective version of the Rortex vector for vortex identification [J]. Physics of Fluids, 2019, 31(6): 065112.
Dong X., Gao Y., Liu C. New normalized Rortex/vortex identification method [J]. Physics of Fluids, 2019, 31(1): 011701.
Liu J., Liu C. Modified normalized Rortex/vortex identification method [J]. Physics of Fluids, 2019, 31(6): 061704.
Gao Y., Liu J., Yu Y. et al. A Liutex based definition of vortex rotation axis line [J]. Journal of Hydrodynamics, 2019, 31(3): 445–454.
Xu H., Cai X. S., Liu C. Liutex (vortex) core definition and automatic identification for turbulence vortex structures [J]. Journal of Hydrodynamics, 2019, 31(5): 857–863.
Wang Y. Q., Gao Y. S., Xu H. et al. Liutex theoretical system and six core elements of vortex identification [J]. Journal of Hydrodynamics, 2020, 32(2): 197–211.
Liu C., Gao Y. Liutex-based and other mathematical, computational and experimental methods for turbulence structure [M]. Sharjah, United Arab Emirates: Benthom Science Publishers, 2020.
Liu C., Xu H., Cai X. et al. Liutex and its applications in turbulence research [M]. Cambridge, Massachusetts, USA: Academic Press, 2020.
Vainchtein D., Meziç I. Vortex-based control algorithms (Koumoutsakos P., Meziç I. Controlof fluid flow. Lecture notes in control and information sciences) [M]. Berlin, Germany: Springer, 2006.
Protas B. Vortex dynamics models in flow control problems [J]. Nonlinearity, 2008, 21(9): 203–250.
Yu H. D., Wang Y. Q. Liutex-based vortex dynamics: A preliminary study [J]. Journal of Hydrodynamics, 2020, 32(6): 1217–1220.
Gao Y., Liu C. Rortex and comparison with eigenvalue-based vortex identification criteria [J]. Physics of Fluids, 2018, 30(8): 085107.
Wang Y. Q., Gao Y. S., Liu J. M. et al. Explicit formula for the Liutex vector and physical meaning of vorticity based on the Liutex-Shear decomposition [J]. Journal of Hydrodynamics, 2019, 31(3): 464–474.
Braza M., Chassaing P., Minh H. Numerical study and physical analysis of the pressure and velocity fields in the near wake of a circular cylinder [J]. Journal of Fluid Mechanics, 1986, 165: 79–130.
Huang B., Wang G. Y. Partially averaged Navier-Stokes method for time-dependent turbulent cavitating flows [J]. Journal of Hydrodynamics, 2011, 23(1): 26–33.
Acknowledgment
Communications with Profs. Liandi Zhou, Chaoqun Liu, and Zheng Ma are highly appreciated.
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Project supported by the National Nature Science Foundation of China (Grant Nos. 11702159, 51879159 and 51909160).
Biography
Yi-qian Wang (1987-), Male, Ph. D., Associate Professor, E-mail: yiqianw@sina.com
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Wang, Yq., Yu, Hd., Zhao, Ww. et al. Liutex-based vortex control with implications for cavitation suppression. J Hydrodyn 33, 74–85 (2021). https://doi.org/10.1007/s42241-021-0013-0
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DOI: https://doi.org/10.1007/s42241-021-0013-0