Study on the power extraction performance of a flapping airfoil power generator using jet flow method

Abstract

Flapping airfoil power generator (FAPG) is becoming popular due to high-power extraction with low noise. However, the effect of a combined jet of suction and blowing on the power extraction performance of the flapping airfoil is not fully explored. The present study presents a flapping airfoil model with a compound jet of suction and blowing, and the jet parameters were optimized using the Taguchi method and CFD approach for the maximum power extraction efficiency of the airfoil. It was found that the power extraction efficiency of the flapping airfoil can be improved by applying the compound jet to the trailing edge of the airfoil. Compared to the baseline NACA0015 airfoil, the optimized jet parameters lead to the maximum improvement in efficiency by 38.14%. The analysis of flow field characteristics of the flapping airfoil reveals that the optimal jet parameters can not only enhance the strength of the vortex on airfoil but also improve the vortex motion mechanism, which results in a greater lift of airfoil and better synergy between the lift and the plunging velocity.