PIV measurements at the LTU test rig are underway

As of last week, a particle image velocimetry (PIV) measurement system has been installed in the LTU test rig. Depending on the optical installation of the PIV system, measurements of either two or three velocity components in the draft tube cone will be performed in a plane passing through the center of the coneThe present optical installation has enabled measurements of two components, and a movie showing the variation in space and time of the axial velocity when the turbine operates at part load can be found below. In the movie, the flow is from left to right and the blue structure that is oscillating in the center signifies the existence of a rotating vortex rope. The measurements are performed as a collaboration between researchers from AFC4HYDRO and the Swedish Hydropower entre (SVC). 

Fig 1- the particle image velocimetry (PIV) measurement system installed in the LTU test rig.


This video gives a glimpse of the analysis of TR PVI (Time Resolved Particle Image Velocimetry) measurements made at LTU and as part of the AFC4Hydro project.