Unsteady aerodynamics of offshore floating wind turbines in platform pitching motion using vortex lattice method

This paper extends the prescribed-wake vortex lattice method (VLM) to perform aerodynamic analysis of dual-rotor wind turbines (DRWTs). A DRWT turbine consists of a large, primary rotor placed co-axially behind a smaller, secondary rotor. The additional vortex system introduced by the secondary rotor of a DRWT is modeled while taking into account the singularities that can occur when the trailing vortices from the secondary (upstream) rotor interact with the bound vortices of the main (downstream) rotor. Pseudo-steady assumption is invoked, and averaging over multiple relative rotor positions is performed to account for the primary and secondary rotors operating at different rotational velocities. The VLM solver is first validated against experiments and blade element momentum theory results for a conventional, single-rotor turbine. The solver is then verified for two DRWT designs against results from two computational fluid dynamics (CFD) methods: (1) Reynolds-averaged Navier–Stokes CFD with an actuator disk representation of the turbine rotors and (2) large-eddy simulations with an actuator line model. Radial distributions of sectional torque force and angle of attack show reasonable agreement between the three methods. Results of parametric sweeps performed using VLM agree qualitatively with the Reynolds-averaged Navier–Stokes (RANS) CFD results demonstrating that the proposed VLM can be used to guide preliminary design of DRWTs.

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Unsteady aerodynamics investigation of deploying tandem-wing with different methods

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410018804737 ◽

2018 ◽

Vol 233 (10) ◽

pp. 3714-3733 ◽

Cited By ~ 1

Author(s):

Hao Cheng ◽

Hua Wang ◽

Qingli Shi ◽

Mengying Zhang

Keyword(s):

Fore Wing ◽

Vortex Lattice ◽

Lift Coefficient ◽

Unsteady Aerodynamics ◽

Lattice Method ◽

Vortex Lattice Method ◽

Induced Drag ◽

Lifting Line ◽

Lifting Line Method ◽

Unsteady Lift

In the rapidly deploying process of the unmanned aerial vehicle with folding wings, the aerodynamic characteristics could be largely different owing to the effects of deformation rate and the aerodynamic interference. The investigation on the unsteady aerodynamics is of great significance for the stability analysis and control design. The lifting-line method and the vortex-lattice method are improved to calculate the unsteady aerodynamics in the morphing stage. It is validated that the vortex-lattice method predicts the unsteady lift coefficient more appropriately than the lifting-line method. Different tandem wing configurations with deployable wings are simulated with different deformation rates during the morphing stage by the vortex-lattice method. As results indicated, the unsteady lift coefficient and the induced drag of the fore wing rise with the deformation rate increasing, but it is reversed for the hind wing. Additionally, the unsteady lift coefficient of the tandem wing configuration performs well with a larger stagger, a larger magnitude of the gap and a larger wingspan of the fore wing; however, the total induced drag has a larger value for the configuration that the two lifting surfaces with the same wingspans are closer to each other.

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Correction: A Quasi-Continuous Vortex Lattice Method for Unsteady Aerodynamics Analysis

2018 AIAA Aerospace Sciences Meeting ◽

10.2514/6.2018-0815.c1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Brenden Epps ◽

David Greeley

Keyword(s):

Vortex Lattice ◽

Unsteady Aerodynamics ◽

Lattice Method ◽

Vortex Lattice Method

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A vortex-lattice method for general, unsteady aerodynamics

Journal of Aircraft ◽

10.2514/3.45078 ◽

1985 ◽

Vol 22 (1) ◽

pp. 43-49 ◽

Cited By ~ 46

Author(s):

P. Konstadinopoulos ◽

D. F. Thrasher ◽

D. T. Mook ◽

A. H. Nayfeh ◽

L. Watson

Keyword(s):

Vortex Lattice ◽

Unsteady Aerodynamics ◽

Lattice Method ◽

Vortex Lattice Method

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Generalized vortex lattice method for planar supersonic flow

AIAA Journal ◽

10.2514/3.13655 ◽

1997 ◽

Vol 35 ◽

pp. 1230-1233

Author(s):

Paulo A. O. Soviero ◽

Hugo B. Resende

Keyword(s):

Supersonic Flow ◽

Vortex Lattice ◽

Lattice Method ◽

Vortex Lattice Method

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Static Aeroelastic Characteristics of Morphing Trailing-Edge Wing Using Geometrically Exact Vortex Lattice Method

International Journal of Aerospace Engineering ◽

10.1155/2019/5847627 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15

Author(s):

Sen Mao ◽

Changchuan Xie ◽

Lan Yang ◽

Chao Yang

Keyword(s):

Vortex Lattice ◽

Deflection Angle ◽

Aircraft Design ◽

Analysis Method ◽

Lattice Method ◽

Trailing Edge ◽

Vortex Lattice Method ◽

Analysis And Design ◽

Aeroelastic Analysis ◽

Typical Model

A morphing trailing-edge (TE) wing is an important morphing mode in aircraft design. In order to explore the static aeroelastic characteristics of a morphing TE wing, an efficient and feasible method for static aeroelastic analysis has been developed in this paper. A geometrically exact vortex lattice method (VLM) is applied to calculate the aerodynamic forces. Firstly, a typical model of a morphing TE wing is chosen and built which has an active morphing trailing edge driven by a piezoelectric patch. Then, the paper carries out the static aeroelastic analysis of the morphing TE wing and corresponding simulations were carried out. Finally, the analysis results are compared with those of a traditional wing with a rigid trailing edge using the traditional linearized VLM. The results indicate that the geometrically exact VLM can better describe the aerodynamic nonlinearity of a morphing TE wing in consideration of geometrical deformation in aeroelastic analysis. Moreover, out of consideration of the angle of attack, the deflection angle of the trailing edge, among others, the wing system does not show divergence but bifurcation. Consequently, the aeroelastic analysis method proposed in this paper is more applicable to the analysis and design of a morphing TE wing.

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