Abstract
SubChannel Void Sensor (SCVS) consisting of electrodes with 6-wire by 6-wire and 5-rod by 5-rod electrodes has been developed to acquire boiling two-phase flow dynamics in 5×5 rod bundle geometry. The SCVS can acquire a local void fraction in 32 points (=6×6-4) of central subchannel regions and 100 points (=4×25) of near rod surface regions. The temporal resolution is up to 5000 frames (cross sections) per second. The devised sensors are installed every 500mm in the heated rod bundle and exhibits the quasi three-dimensional boiling two-phase flow structures, i.e. void fraction distribution.
