Gas-liquid two-phase flow in large space. Basic examination based on a two-dimensional, air-water experiment

A two-dimensional air-water experiment under atmospheric pressure and low void fraction condition was conducted in order to study gas-liquid two-phase flow behavior in large space. The data obtained from this experiment can also be used to verify the accuracy of multi-dimensional two-phase flow analysis. The test facility consisted of a bubble injection section, an upward flow section and two downward flow sections. The upward flow section was much wider than bubble size. When bubble injection into the upward flow section was not uniform, the path of bubbles oscillated in some cases. The oscillation frequency was classified as high and low. When the frequency was low, the liquid velocity at the downward flow section oscillated at the same frequency. When bubbles were uniformly injected into the upward flow section, the liquid velocity was slightly faster if the upward flow section was not partitioned than if it was partitioned into nine narrow watercourses. This demonstrates that the vortex which prevented the circulation flow was not formed in the upward flow section. (author)