Two-dimensional distribution measurement of in-plane velocity component using bias-frequency spatial encoding

Abstract

We propose a differential laser Doppler velocimeter (LDV) for two-dimensional (2D) distribution measurements of the in-plane velocity component based on bias-frequency spatial encoding. Using two crossing beam arrays, the structure can effectively assign bias frequencies to the measurement points over a 2D area. As a feasibility study of the proposed method, velocity distribution measurements were conducted using a 4 × 4-channel optical setup. The experimental results indicate that the proposed method could successfully measure the 2D distribution of the in-plane velocity component.