On the Structure of Turbulent Bubbly Gas-Liquid Flows

Abstract

Abstract To gain understanding of the structure of turbulent bubbly gas (or vapor)-liquid flows, local measurements have been carried out in the bubbly regime of isothermal gas-liquid flow and boiling flow. The isothermal flow was created by injecting nitrogen gas into an upward flow of liquid Refrigerant-113 through a vertical pipe. The boiling flow, of Refrigerant-113, was created in a vertical annular channel whose inner wall was heated. In both flows, the radial distributions of gas (or vapor) residence time fraction, bubble mean axial velocity, and bubble diameter were measured by a dual-sensor fiberoptic probe. In the liquid phase of the flows, the radial distributions of mean axial and radial velocities, axial and radial turbulent intensities, and axial Reynolds shear stress were measured by a two-component laser Doppler velocimeter (LDV). The radial distributions of bubble mean axial velocity and axial velocity fluctuation intensity were also measured by the LDV. Vapor and liquid temperature radial distributions in boiling flow were obtained by a fast-response microthermocouple. A multidimensional two-fluid model of turbulent bubbly gas (or vapor)-liquid flow is being developed at Electricité de France with contribution from our experimental and turbulence modeling work.