Experimental investigation of the velocity field in a turbomachine passage by using Laser Doppler Velocimetry (LDV)

A model was manufactured and a test set-up was built to determine the velocity field in the axis symmetric meridional channel of a mixed-flow machine. The model provides optical accessibility to the flow and the test set-up provides stable flow conditions, The flow in the bladeless space of the meridional channel was investigated. The results serve as tools for checking the theoretical results based on different assumptions and turbulence models. The spatial curvature of the channel wall makes the application of the LDV difficult. The problems and the solutions are presented in this paper.