Near Wall Velocity Distribution of Turbulent Swirling Flow in Circular Pipe

Abstract

Velocity distributions dose to wall of a turbulent swirling flow in a circular pipe have been measured. Unlike the ordinary parallel flow the streamline of swirling flow twists helically downstream, which may change the structure of flow in wall region as is expected from the study of streamline curvature effects of a two-dimensional curved flow. Effect of streamline curvature is characterized by a parameter Ω, nondimensionalized angular momentum flux, by which the flow is classified as (1) not influenced, (2) partially influenced and (3) completely influenced according to the magnitude of Ω. The flow is found to be three-dimensional when Ω surpasses 0.186.