AN EXPERIMENTAL INVESTIGATION OF TURBULENT WAKE BEHIND 'S'-SHAPED PROFILES.

The wake characteristics behind a cascade of 'S' profiles have been studied under turbine and pump conditions at wider and closer spacings. The mean velocity distributions indicate asymmetry predominantly during pump cascade condition and for high cambered 'S' profiles. The higher total pressure loss under decelerating flow conditions was indicated by larger values of wake momentum thickness. Sample turbulence measurements made also show asymmetry. The region of maximum turbulence intensity is skewed towards one side of the wake.