INFLUENCE OF BLUNT TRAILING EDGE ON ENERGY HARVESTING CHARACTERISTICS OF FLAPPING AIRFOIL

Zhang Gang; Sun Xiaojing

doi:10.19912/j.0254-0096.tynxb.2022-0057

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Acta Energiae Solaris Sinica ›› 2023, Vol. 44 ›› Issue (5) : 457-465. DOI: 10.19912/j.0254-0096.tynxb.2022-0057

INFLUENCE OF BLUNT TRAILING EDGE ON ENERGY HARVESTING CHARACTERISTICS OF FLAPPING AIRFOIL

Zhang Gang^1,2, Sun Xiaojing^1,2

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Abstract

The flapping airfoil energy harvester is a device that extracts energy from ocean currents through the heave and pitch motions. The numerical simulation of the energy harvesting characteristics of flapping wing with blunt trailing edge is carried out by means of computational fluid dynamics（CFD）. Influences of the initial position to symmetrically thicken the trailing edge, thickness of the blunt trailing edge and the airfoil thickness on the energy harvesting efficiency of the flapping airfoil were systemically investigated. The results show that there is an optimal ratio of the initial position to symmetrically thicken the trailing edge to the chord length of the airfoil p/c=0.90, at which the largest increase in the efficiency of the flapping airfoil can be achieved. It is also found that the influence of the blunt trailing edge thickness on the performance of a flapping airfoil is more significant in the range of the middle and high reduction frequency. In general, the energy harvesting efficiency of the flapping airfoil increases at first and then decreases with the increase of the blunt trailing edge thickness. When the ratio of the blunt trailing edge thickness to the chord length of airfoil l/c=0.02, the improvement influence of the energy harvesting efficiency of the blunt trailing edge flapping airfoil reaches the threshold. As the thickness of the airfoil gradually increases, the energy harvesting efficiency of blunt trailing flapping airfoil first increases and then decreases, and reaches its peak when the airfoil is NACA0030.

Key words

wind turbines / computational fluid dynamics / thickness / position / energy harvesting flapping airfoil / blunt trailing edge

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Zhang Gang, Sun Xiaojing. INFLUENCE OF BLUNT TRAILING EDGE ON ENERGY HARVESTING CHARACTERISTICS OF FLAPPING AIRFOIL[J]. Acta Energiae Solaris Sinica. 2023, 44(5): 457-465 https://doi.org/10.19912/j.0254-0096.tynxb.2022-0057

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