VISCOSITY EFFECTS IN A CHANNEL OF SMALL EXPONENTIAL DIVERGENCE

Abstract

An experimental investigation of a flow form, deduced by Blasius from theoretical considerations, was carried out with air as the medium. A photographic method of measuring velocity distributions was adopted, and a diverging channel was designed from considerations based on the theoretical treatment and on requirements arising out of the experimental method. At a Reynolds number of 35, curves of velocity distribution were measured at various positions along the channel, and comparisons were then made with the corresponding theoretical curves. Good agreement was found over the region of the channel to which the theoretical results could be applied. A study of the experimental curves in that part of the channel to which the theoretical results could not be applied quantitatively showed further that the general flow characteristics described by Blasius are to be found in this region.