Shear stresses in turbulent flow through concentric annuli

Bibliography: pages 161-164.A novel experimental approach to the direct measurement of wall shear stresses in fully developed turbulent flow in concentric annuli is presented. By means of a specially constructed 6 m test rig known as the 'floating sleeve', results of individual wall shear stresses, friction factors and shear stress distributions were obtained for Reynolds numbers from 25 000 to 220 000 with radius ratios from 0,091 to 0,376. Tests were conducted using both smooth and rough annuli. A summary of previous investigations and an examination of the measuring devices most commonly used in annular flow are also presented