Experimental Investigation of Skin Friction on Smooth Surfaces Supporting Air Bearing Channels

摘要

A new method, to obtain skin friction reduction by installing air-bearing channels on a smooth surface in uniform flow was investigated. The measurements were made by a servo-controlled skin friction balance. The parametric studies of the channel having step dimensions less than the laminar sublayer thicknesses and placed in flows of free stream velocity up to 90 ft/s have shown that an average skin friction reduction of 25% in the air bearing cavity is well within reach. It was also confirmed that riblet type surface grooves can produce up to 10% skin friction drag reduction.