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Review of vortex methods for rotor aerodynamics and wake dynamics

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Advances in Aerodynamics 2022年第1期4卷 413-448页

作者： H.Lee B.Sengupta M.S.Araghizadeh R.S.Myong School of Mechanical and Aerospace Engineering Gyeongsang National UniversityJinjuGyeongnam52828South Korea

Electric vertical take-off and landing(eVTOL)aircraft with multiple lifting rotors or prop-rotors have received significant attention in recent years due to their great potential for next-generation urban air mobility(UAM).Numerical models have been developed and validated as predictive tools to analyze rotor aerodynamics and wake *** various numerical approaches,the vortex method is one of the most suitable because it can provide accurate solutions with an affordable computational cost and can represent vorticity fields downstream without numerical dissipation *** paper presents a brief review of the progress of vortex methods,along with their principles,advantages,and *** of the vortex methods for modeling the rotor aerodynamics and wake dynamics are also ***,the vortex methods suffer from the problem that it cannot deal with the nonlinear aerodynamic characteristics associated with the viscous effects and the flow behaviors in the post-stall *** overcome the intrinsic drawbacks of the vortex methods,recent progress in a numerical method proposed by the authors is introduced,and model validation against experimental data is discussed in *** validation works show that nonlinear vortex lattice method(NVLM)coupled with vortex particle method(VPM)can predict the unsteady aerodynamic forces and complex evolution of the rotor wake.

关键词： vortex methods Nonlinear vortex lattice method Viscous vortex particle method Rotor aerodynamics Wake dynamics

Novel Dynamics of a vortex in Three-Dimensional Dissipative Media with an Umbrella-Shaped Potential

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Chinese Physics Letters 2014年第7期31卷 121-124页

作者：刘云凤刘彬何兴道李淑静 Key Laboratory of Nondestructive Test (Ministry of Education) Nanchang Hangkong University Nanchang 330063

We report the novel dynamic of 3D dissipative vortices supported by an umbrella-shaped potential （USP） in the 3D complex Ginzburg-Landau （GGL） equation with the cubic-quintic nonlinearity. The stable solution of vortices with intrinsic vorticity S=1 and 2 are obtained in the 3D GGL equation. An appropriate USP forces the vortices continuously to throw out fundamental 3D solitons （light bullets） along the folding umbrella. The dynamic regions of the strength of the potential with the changing number of folding umbrella are analyzed, and the rate of throwing increases with the strength of the potential. A weak potential cannot provide vortices with enough force. Then, the vortices will be stretched into polygons. However, a strong potential will destroy the vortices.

关键词： DYNAMICS vortex methods ENERGY dissipation POTENTIAL energy SOLITONS

Numerical　Simulation　of　the　Flow　over　a　Model　of　the　Cavities　on　a　Butterfly　Wing

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Journal of Thermal Science 1995年第3期4卷 185-192页

作者： Rodrigue Savoie Yves Gagnon (University de Moncton, Campus d’Edmundston, Edmundston (NB) Canada) Université de Moncton Campus d’Edmundston Edmundston Canada

The objective of this paper is to present results of numerical simulations for the flow over cavities modeling the scale structures on the upper surface of a typical butterfly wing. The numerical results,obtained using a vortex method, show that the dynamics of the flow are strongly dependent on the Reynolds number of the flow. The large coherent structures, formed in the cavity of adjoining scales, exhibit a stationary behaviour for low Reynolds number flows, while they exhibit strong dynamics and instabilities for high Reynolds number flows. The numerical results are in very good agreement with corresponding experimental results available in the literature.

关键词： vortex methods vorticity cavity butterfly.

Utilization of Different Variables for the Visualization of Fluid Flows: Application to Instantaneous Channel Flows

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Journal of Thermal Science 2001年第2期10卷 116-122页

作者： Gerard J. Poitras New Brunswick Cornmunity College, Edmundston (NB), Canada L.-Emmanuel Brizzi Laboratoire d’etudes aerodynamiaues, Universite de Poitiers, 86960 Futuroscope, France Yves Gagnon Faculte des studes superieures et de la recherche, Universite New Brunswick Community College Edmundston Canada Laboratoire d’études aérodynamiques Université de Poitiers Futuroscope France Faculté des études supérieures et de la recherche Université de Moncton Moncton Canada

The results of different numerical algorithms for the computation of unsteady fluid flows are used to visualize different variables of the flow. In particular, the instantaneous vorticity, velocity and pressure fields, along with streamline plots, are presented as a function of time inside a visualization window of the computational domain. The different forms of visualization are used to analyze the flow inside a two-dimensional channel incorporating an obstacle, which can represent several interesting flows such as the flow over electronic components, heat transfer devices and buildings.

关键词： vortex methods finite volume method velocity field pressure vorticity.

Recent development of vortex method in incompressible viscous bluff body flows

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第4期6卷 283-288页

作者：刘兰嵇峰樊建人岑可法 Clean Energy & Environment Engineering Key Laboratory of Ministry of Education and Institute for Thermal Power Engineering Zhejiang University

vortex methods have been alternative tools of finite element and finite difference methods for several decades. This paper presents a brief review of vortex method development in the last decades and introduces efficient vortex methods developed for high Reynolds number bluff body flows and suitable for running on parallel computer architectures. Included in this study are particle strength exchange methods, core-spreading method, deterministic particle method and hybrid vortex methods. Combined with conservative methods, vortex methods can comprise the most available tools for simulations of three-dimensional complex bluff body flows at high Reynolds numbers.

关键词： vortex methods Simulation of flows Bluff body