Components for a planar three–component velocimeter using Doppler global velocimetry (DGV) and PIV

Doppler global velocimetry (DGV) is a planar velocity measurement technique which is based on the determination of the Doppler shift of laser light scattered off particles by using a molecular filter. Currently a pulsed Doppler global velocimeter is being constructed at the Institute of Fluid Dynamics. The out–of–plane component of each velocity vector in the laser‐illuminated plane is obtained by that configuration. The experimental setup is extended so as to measure the in–plane component of those velocity vectors by using particle image velocimetry (PIV). Thus, a measurement system is being developed which is capable of obtaining three components of the velocity vectors located in a plane by using one single camera system. Due to the elaborate setup which includes a pulsed laser system, a filter cell and a camera system, the overall system quality is strongly connected to the technical performance of each single component. Therefore the technical specifications of all velocimeter components have been evaluated experimentally. Evaluation data are presented in this report.