抄録
This experimental study has performed on vertical, upward, gas-liquid two-phase flow through a round tube with an axisymmetric sudden expansion part (20 mm φ to 50 mm φ). The flow patterns in the case of the sudden pipe expansion were observed by using the high-speed video camera. The observations revealed that the sudden expansion flow patterns had the multi-dimensional behaviors, i.e., the singular phenomena in the sudden expansion part, such as straight-up flow, reattahment point, recirculating flow, deformation and break-up of the slug and bubble, etc., were clarified.
