AbstractThis study is an effort to comprehend the description of the vapour-liquid flows associated with the transformation of the phase, which may assist in determining mass, momentum and energy transfer within the interfacial region containing the steam and water. This study describes the development of a void fraction measurement sensory system, which is based on AC based electrodes, referred scientifically as Electrical Resistance Tomography (ERT) system. ERT sensors based system was applied to emphasize the phenomenon involving supersonic steam injection into a column of water. Data acquisition system supporting the ERT technique was applied for the given time interval and the acquired data was processed by using a free code known as EIDORS. Images thus obtained by use of EIDORS provided a planar picture of supersonic steam jet surrounding by the water in a vessel. Images represent the broadly visible boundaries among steam and water phases, and the turbulent interface between them. It has been found that with rising temperature 30–60°C, the area under the effect of the steam jet has been increased from 46.51–65.40% at 3.0 bar of steam’s inlet pressure.