Improvement of Energy Extraction Efficiency for Flapping Airfoils by Using Oscillating Gurney Flaps

Bouzaher, Mohamed Taher; Drias, Nouredine; Guerira, Belhi

doi:10.1007/s13369-018-3270-7

Cited by 9 publications

(3 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another way to improve extraction efficiency can also be achieved by creating an effective camber which will produce a lift enhancement that is associated with the output power. This concept was studied by Bouzaher et al [29], who added a Gurney flap at the trailing-edge that when synchronized with the flapping motion at a Re = 1100 created this virtual camber that improved the output power. The lift production can be further improved by controlling the development of the leading-edge vortex than, when attached to the airfoil surface, contributed to the improvement in lift generation which brings once again an increase in the energy harvesting magnitude [24].…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Frequency and Amplitude Influence on a Plunging NACA0012

et al. 2020

View full text Add to dashboard Cite

Natural flight has always been the source of imagination for Mankind, but reproducing the propulsive systems used by animals that can improve the versatility and response at low Reynolds number is indeed quite complex. The main objective of the present work is the computational study of the influence of the Reynolds number, frequency, and amplitude of the oscillatory movement of a NACA0012 airfoil in the aerodynamic performance. The thrust and power coefficients are obtained which together are used to calculate the propulsive efficiency. The simulations were performed using ANSYS Fluent with a RANS approach for Reynolds numbers between 8500 and 34,000, reduced frequencies between 1 and 5, and Strouhal numbers from 0.1 to 0.4. The aerodynamic parameters were thoroughly explored as well as their interaction, concluding that when the Reynolds number is increased, the optimal propulsive efficiency occurs for higher nondimensional amplitudes and lower reduced frequencies, agreeing in some ways with the phenomena observed in the animal kingdom.

show abstract

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Frequency and Amplitude Influence on a Plunging NACA0012

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Bouzaher et al [27], added a gurney flap to the trailing edge of a flapping turbine at Re = 1100. When the motion of the GF synchronized with the flapping motion, a virtual camber was generated, which helped to improve the output power.…”

Section: Introductionmentioning

confidence: 99%

Efficiency Improvement of Darrieus Wind Turbine Using Oscillating Gurney Flap

Zereg,

Aksas,

Bouzaher

et al. 2024

Fluids

Self Cite

View full text Add to dashboard Cite

In this work, a new model of Darrieus wind turbines with an oscillating gurney flap (OGF) is proposed. A detailed 2D computational fluid dynamics (CFD) investigation is carried out using ANSYS-Fluent 22.0 to assess the turbine performance. The OGF can alter its position between the upper and lower blade surfaces during the turbine rotation. Equations related to the combined motion are implemented through a user-defined function (UDF). The proposed model is validated where a good coincidence is achieved. The overset dynamic mesh method is used. It was found that a judicious synchronization of OGF and turbine blades creates beneficial vortex interactions, which correct the pressure distribution and lead to an overall improvement in the lift force. The magnitude of the improvement is highly dependent on the OGF length and the phase motion φ. The average torque coefficient Cm for the controlled case increased by more than 19% in comparison with the nominal case.

show abstract

“…Modifications of the blade designs itself influence the performance of VAWTs. Different techniques have been used for boosting up the power coefficient (Cp) of H-Darrieus VAWT; such as deforming blades at leading edge [1] and trailing edge [2,3], using gurney flap [4] and flapped airfoil . Blade twist is also identified as a means for improving the VAWT's performance.…”

Section: Introductionmentioning

confidence: 99%

A 2D numerical simulation of blade twist effect on the aerodynamic performance of an asymmetric blade vertical axis wind turbine in low wind speed

Mazarbhuiya¹,

Biswas²,

Sharma³

2018

EAI Endorsed Transactions on Energy Web

View full text Add to dashboard Cite

For urban areas, small-scale vertical axis wind turbine (VAWT) is a promising energy harvester due to its compact structure. However, VAWT's performance is inferior in low wind speed of urban environment. Selection of proper design and operational parameters can give a desirable power output under such condition. In this paper, effect of trailing edge blade twist on aerodynamic performance of an asymmetric blade H-Darrieus VAWT at a wind speed (6.0 m/s) is investigated using 2D numerical simulation. Important aerodynamic parameters considering blade twists have been analysed. Although blade twist has not increased power coefficient magnificently, the same is improved with blade twist of 1º. However, further increase of the latter reduces the turbine performance. A maximum power coefficient of 0.171 is obtained at tip speed ratio 2.4 for 1º blade twist configuration. Hence, the present study shows that blade twist should be very low for low wind speed application of H-Darrieus VAWT.

show abstract

Improvement of Energy Extraction Efficiency for Flapping Airfoils by Using Oscillating Gurney Flaps

Cited by 9 publications

References 20 publications

Numerical Investigation of Frequency and Amplitude Influence on a Plunging NACA0012

Numerical Investigation of Frequency and Amplitude Influence on a Plunging NACA0012

Efficiency Improvement of Darrieus Wind Turbine Using Oscillating Gurney Flap

A 2D numerical simulation of blade twist effect on the aerodynamic performance of an asymmetric blade vertical axis wind turbine in low wind speed

Contact Info

Product

Resources

About