Numerical investigations of the flow control effect on a thick wind turbine airfoil using deformable trailing edge flaps

Yan, Qian; Zhang, Yuquan; Sun, Yuqing; Wang, Tongguang

doi:10.1016/j.energy.2022.126327

Cited by 13 publications

(5 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Notable deviations are discernible during the downstroke motion, attributable, at least in part, to inherent limitations associated with unsteady RANS turbulence modeling -a phenomenon corroborated in other numerical simulations [39]. Analogous findings have also been reported in related literature by Qian et al for example [40]. Consequently, even though k − ω SST is highly recommended in the literature, when it is not accompanied with a proper mesh resolution close to the walls (i.e., y+ ≈ 1, and ∆y/∆z ≈ 1, which does not apply to the present case) under the actual dynamic stall conditions, strong numerical instabilities emerge, which slow down the convergence rate, and therefore the simulation, and additionally prompt the use of lower-order numerical time schemes.…”

Section: Sensitivity Analysissupporting

confidence: 80%

Sensitivity Analysis of an Unsteady Flow Around a Pitching Airfoil

Añez,

Hamdani,

Reveillon

et al. 2023

OpenFOAM J

View full text Add to dashboard Cite

Various ways to control the loads and thus the output of the wind turbine by pitching the blades and by controlling the rotational speed already exist. However, adverse pressure gradient leading to flow separation at the trailing edge, with relatively high angles of attack (AOA) due to blade-pitching motion, largely affects the airfoil aerodynamic performance. This work presents the results of a numerical study of the unsteady flow around a pitching FFA-W3-301 airfoil at a Reynolds 1.6 × 106 using OpenFOAM®, as obtained by first performing 2D Unsteady Reynolds-Averaged Navier- Stokes (URANS) simulations whereby the flow characteristics are simulated by the shear stress transport (SST) k − ω model and Spalart-Allmaras (SA). The influence of various parameters on the numerical results is investigated, namely y+, computational grid resolution, dynamic mesh technique, time step and turbulence model. Integral aerodynamic forces and detailed flow patterns are compared with experimental measurements presented in the literature. A range of angles of attack, including early stalls, are examined. For best-performing parameters, an adequate refinement close to the wall was imperative in order to match experiments, especially during the upstroke motion of the airfoil, while for the downstroke phase, some differences still appeared. The agreement was greatly improved by using a 2.5D hybrid RANS-LES approach with enhanced delayed-Detached Eddy Simulation (DES) capabilities.

show abstract

Section: Sensitivity Analysissupporting

confidence: 80%

Sensitivity Analysis of an Unsteady Flow Around a Pitching Airfoil

Añez,

Hamdani,

Reveillon

et al. 2023

OpenFOAM J

View full text Add to dashboard Cite

show abstract

“…Reports indicate that lift coefficient and lift-to-drag ratio increase with greater flexure, delaying the stall attack angle [24]. Activated trailing edge deformation with appropriate parameters can reduce lift fluctuation of the pitching foil for HAT [25]. Numerical studies on the energy-harvesting performance of an oscillating hydrofoil with activated chordwise deformation showed improved lift and energy-harvesting capabilities due to increased pressure difference between upper and lower surfaces [26][27][28].…”

Section: Of 21mentioning

confidence: 99%

Numerical Study on Hydrodynamic Performance of a Pitching Hydrofoil with Chordwise and Spanwise Deformation

Qu,

Li,

Dong

2024

JMSE

View full text Add to dashboard Cite

The hydrofoil plays a crucial role in tidal current energy (TCE) devices, such as horizontal-axis turbines (HATs), vertical-axis turbines (VATs), and oscillating hydrofoils. This study delves into the numerical investigation of passive chordwise and spanwise deformations and the hydrodynamic performance of a deformable hydrofoil. Three-dimensional (3D) coupled fluid–structure interaction (FSI) simulations were conducted using the ANSYS Workbench platform, integrating computational fluid dynamics (CFD) and finite element analysis (FEA). The simulation involved a deformable hydrofoil undergoing pitching motion with varying elastic moduli. The study scrutinizes the impact of elastic modulus on hydrofoil deformation, pressure distribution, flow structure, and hydrodynamic performance. Coefficients of lift, drag, torque, as well as their hysteresis areas and intensities, were defined to assess the hydrodynamic performance. The analysis of the correlation between pressure distribution and deformation elucidates the FSI mechanism. Additionally, the study investigated the 3D effects based on the flow structure around the hydrofoil. Discrepancies in pressure distribution along the spanwise direction result from these 3D effects. Consequently, different chordwise deformations of cross-sections along the spanwise direction were observed, contributing to spanwise deformation. The pressure difference between upper and lower surfaces diminished with increasing deformation. Peak values and fluctuations of lift, drag, and torque decreased. This study provides insights for selecting an appropriate elastic modulus for hydrofoils used in TCE devices.

show abstract

“…The RNG k-ε model, proposed by Yakhot and Orszag (1986), is based on the renormalization group method. Similar in form to the standard k-ε, this theory yields an effective viscosity derived from the analysis, accounting for the influence of low Reynolds numbers and the appropriate treatment of the near-wall region by utilizing the Gaussian statistical method under equilibrium conditions [24]. After performing a series of operations to eliminate small-scale components and rescale the residual portion, the equation governing large-scale motion is obtained, enabling better management of flows with elevated strain rates and streamline curvature, thereby enhancing computational accuracy [25].…”

Section: Numerical Modelmentioning

confidence: 99%

Research on Wake Field Characteristics and Support Structure Interference of Horizontal Axis Tidal Stream Turbine

et al. 2023

View full text Add to dashboard Cite

The harnessing and utilization of tidal current energy have emerged as prominent topics in scientific inquiry, due to their vast untapped resource potential, leading to numerous investigations into the efficacy of hydrokinetic turbines under various operational conditions. This paper delineates the wake field characteristics and performance of horizontal axis tidal stream turbines under the influence of support structures, using a comprehensively blade-resolved computational fluid dynamics (CFDs) model that employs Reynolds-averaged Navier–Stokes (RANS) equations in combination with the RNG k-ε turbulence model. To achieve this, the study utilized experimental tank tests and numerical simulations to investigate the distribution characteristics and recuperative principles of the turbine’s wake field. The velocity distribution and energy augmentation coefficient of the wake field showed strong agreement with the experimental results. To further assess the effect of support structures on the flow field downstream of the unit and its performance, the hydrodynamic attributes of the turbine wake field were analyzed with and without support structures. The interference elicited by the support structure modified the velocity distribution of the near-wake flow field, resulting in a 4.41% decrease in the turbine’s power coefficient (Cp), significantly impacting the turbine’s instantaneous performance.

show abstract

Numerical investigations of the flow control effect on a thick wind turbine airfoil using deformable trailing edge flaps

Cited by 13 publications

References 23 publications

Sensitivity Analysis of an Unsteady Flow Around a Pitching Airfoil

Sensitivity Analysis of an Unsteady Flow Around a Pitching Airfoil

Numerical Study on Hydrodynamic Performance of a Pitching Hydrofoil with Chordwise and Spanwise Deformation

Research on Wake Field Characteristics and Support Structure Interference of Horizontal Axis Tidal Stream Turbine

Contact Info

Product

Resources

About