Design and Numerical and Experimental Investigation of Pre-Swirl Stators PSS

This paper describes a CFD based approach to the design of
a Pre-Swirl Stator (PSS) to be used as Energy Saving
Device (ESD) on a retrofit chemical tanker. The designed
PSS is shown to deliver 4% power savings at vessel selfpropulsion
condition through a relevant speed range in full
scale. This is close to the maximum gain statistically
achievable with this type of ESD, under comparable
propeller loading. Analysis of velocity and kinetic energy
fields is presented to explain the mechanisms behind power
saving. An extensive experimental program, including flow
field measurements without and with ESD, is conducted to
provide additional validation material on the present ship
and to verify the ESD performance.