AN EXPERIMENTAL STUDY ON FREEZE VALVE PERFORMANCE IN A MOLTEN SALT REACTOR

摘要

Freeze valve technology is the main feature of safety system in the molten salt reactor. Freeze valve made from frozen salt located between reactor core and drain tank. The freeze valve will automatically melt and open on the accident condition, and respectively molten salt fuel will drain out from reactor core to the drain tanks. Melting time of frozen salt is important issues on this study, where draining process of the liquid fuel must be carried out immediately after the accident. Many factors affect to the opening time of freeze valve. On this experiment, describe a melting process of frozen salt which is affected by wall effect. HTS (high transfer salt) utilized as salt material, and a metal stick planted in the frozen HTS with a certain depth. The experimental process begins when the liquid HTS poured on the top of frozen HTS and ends when the metal stick detached from the frozen HTS. This experiments focus to analyze melting time of freeze valve which impacted by several parameters; material diameter which represent about material thickness in real situation, liquid temperature which represent about molten salt fuel, length of material which propose about the freeze valve thickness, and material difference which propose about thermal diffusivity effect. Results from the experiments will be utilized as a basic to developed mathematics and numerical analysis.