流体中速度矢量场检测方案(粒子图像测速)

The active control of laminar and turbulent flows with dynamical actuators is of great scientific and technological interest in nearly any field of fluid mechanics. On on hand it becomes possible to generate artifical flow structures whose properties and significance for the turbulent mixing, or their interaction with other flow structures, can be examined. On the other hand, these devices suppress flow separation on profiles or increase the performance of flow engines. Today, most of the well established actuator concepts are based on pneumatic and micro-mechanic basis. However, owing to their limited dynamic range their potential seems to be limited from the present point of view, see Gad-el-Hak (2001), and also their technical implementation is sometimes difficult. In the following an optical actuator concept is proposed and examined that allows to excite the flow non-intrusively with nearly any pulse-width and repetition-rate.