Turbulent Boundary Layer on a Rotating Disk in an Infinite Quiescent Fluid

Abstract

An experimental study of the turbulent flow due to a rotating disk in an infinite quiescent fluid was conducted. Using a single normal or inclined-type hot wire, mean velocities and all the six components of the Reynolds stress were measured for various local Reynolds numbers Rel. The circumferential velocity profiles, normalized by the wall variables, in the semilogarithmic plot show a linear variation in the fully turbulent region. When Rel = 1.0×106, this profile is in close agreement with that for the flat-plate boundary layer. The circumferential component of the turbulence intensity reaches a maximum value in the buffer region. All components of the turbulence intensity, normalized by the friction velocity, were found to be considerably smaller than those for the flat-plate boundary layer except very near the wall. The values of the structure parameter a1 are smaller than those for the flat-plate boundary layer. © 1992, The Japan Society of Mechanical Engineers. All rights reserved.