Liquid Flow Characteristics in an Air-Water Bubbling Wall Jet Rising Along a Vertical Flat Plate

摘要

An air-water bubbling jet was generated vertically upward along a vertical flat plate. The liquid flow characteristics represented by the axial mean velocity and the root--mean--square value of the axial turbulence component, designated by u and U_rms, were measured with a two-channel laser Doppler velocimeter. The horizontal distributions of u and U_rms followed their respective similar distributions in the vertical region where the buoyancy force acting on bubbles governs the flow field just like the distributions of bubble frequency and void fraction. An empirical equation was proposed for the horizontal distribution of u. The skewness and flatness factors for the axial turbulence component were also discussed to describe the structure of turbulence in more detail.