Measurement of void distribution by ultra fast X-ray computed tomography scanner

An advanced high-speed X-ray computed tomography (CT) scanner system has been developed. A prototype system with a scanning time of 3.6 milliseconds was developed at first, and the feasibility was confirmed to measure the dynamic events of two-phase flow. However, more faster scanning speed is generally required for the practical use in the thermalhydraulics research field. Therefore, the development of advanced type was performed. This advanced type can operate under the scanning time of 0.5 milliseconds and was applied for the instantaneous void distribution measurement of the air-water two-phase flow in the 3x3 rod bundle with grid spacers. The measured results show that the effect of the mixing vane on the void distribution. (author)