Flow structure and bubble characteristics of steam-water two-phase flow in a large-diameter pipe

摘要

The flow structure and bubble characteristics of steam-water two-phase upward flow were observed in a vertical pipe 155 mm in inner diameter. Experiments were conducted under volumetric flux conditions of JG<0.25 m s~-1 and J_L<0.6 m s~-1, and three different inlet boundary conditions to investigate the developing state of the flow. The radial distributions of flow structure, such as void fraction, bubble chord length and gas velocity, were obtained by horizontally traversing optical dual void probes through the pipe. The spectra of bubble chord length and gas velocity were also obtained to study the characteristics of bubbles in detail.