Data from: Effects of the insect body size on the wing leading-edge vortex

Stable attachment of a leading-edge vortex (LEV) plays a key role in generating the high lift on insect wings. The insect's body-size can affect the LEV structure broadly in two ways. First, an overall change in the size changes the Reynolds number, which is known to have an influence on the LEV structure. Second, it may affect the Coriolis acceleration acting across the wing, depending on the wing-offset from the axis of rotation. To investigate this, the effects of Reynolds number and the wing-offset are independently studied for a rotating wing. The three-dimensional LEV structure is mapped using a scanning PIV technique. The rapid acquisition of images and their correlation are carefully validated. The results presented in this paper show that the LEV structure changes mainly with the Reynolds number. However, it is found to be only minimally affected by changing the central body radius over a wide range of body sizes.

前缘涡（Leading-edge Vortex, LEV）的稳定附着是昆虫翼产生高升力的关键因素。昆虫体型可通过两种主要途径对前缘涡结构产生广泛影响：其一，体型的整体变化会改变雷诺数（Reynolds Number, Re），而雷诺数对前缘涡结构的影响已被学界广泛证实；其二，根据翼体相对于旋转轴的偏移量差异，体型变化可能会影响作用于翼面的科里奥利加速度（Coriolis Acceleration）。为探究该问题，本研究针对旋转翼分别开展了雷诺数与翼体偏移量的独立影响实验。研究采用扫描式粒子图像测速技术（Particle Image Velocimetry, PIV）对三维前缘涡结构进行了成像测绘。图像的快速采集及其相关性分析均经过了严格的验证。本文呈现的实验结果表明，前缘涡结构主要随雷诺数发生变化，但在较大的体型变化范围内，中心体半径的改变对前缘涡结构的影响微乎其微。