Wave velocities and wave widths were determined using the wave-vein analysis for a wide range of air and water flow rates. Distinct features of huge waves and disturbance waves were easily recognized from the relations of uTave velocities to wave widths under limited flow conditions. Cluster analysis by K-mean algorithm, which deals with three parameters such as wave velocity, wave width and maximum liquid holdup, was applied in order to distinguish between huge waves and disturbance waves under the given experimental conditions. Individual waves distinguished by the cluster analysis correspond to those recognized from the relations between wave velocities and wave widths. Additional information on the interfacial profile detected by semi-supermultiple point electrode probes was utilized to distinguish huge waves from liquid slugs. Flow conditions for the appearance of liquid slugs, huge waves and disturbance waves are clarihed, and a new flow map is Presented.
