An image processing approach for two-phase interfaces visualized by a real time neutron radiography technique

An image enhancement technique for a visualization of gas–liquid metal two-phase interfaces is developed for a real time neutron radiography (RTNR) technique, where the dynamic motion of bubbles inside liquid metal cannot be observed optically. The proposed image enhancement technique consisted of noise reduction, pipe–fluid interface determination, and image smoothing procedures. The results show that the RTNR technique is able to visualize the dynamics of gas–liquid metal interfaces, and also is able to determine more accurate two-phase flow parameters such as void fraction.