Table 1. Parameters and Boundary Conditions Used in the Experiments.

parameter	case 1	case 2	case 3	unit
pipe diameter	0.05	0.05	0.05	M
superficial gas velocity	1.0–10.0	1.0–10.0	1.0–10.0	m/s
superficial liquid velocity	0.20–0.53	0.20–0.53	0.20–0.53	m/s
temperature	20	20	20	°C
curvature	1	1.5	2	M
water density	998.3	998.3	998.3	kg/m3
gas density	1.20	1.20	1.20	kg/m3
surface tension	0.076	0.076	0.076	N/m