Heat Transfer Analysis in the Hydraulic Transfer System

The targets inside the pipe is transferred by hydraulic force due to pump operation. The ITA is installed in the reflector of the reactor core, and the targets are irradiated in the ITA. The speed of targets shall be limited not to exceed the specified reactivity insertion rate. Because the speed of target can be controlled by the drag force and the hydraulic force, the selection of the inner diameter of the pipe is the key factor to design the HTS. During irradiation, the heat is generated from the targets; therefore, the heat transfer analysis shall be carried out for evaluating whether boiling water occurs or not. This deign requirement is also involved in determining the inner diameter of the pipe. Thus, the selection of the pipe size shall be taken into account from the viewpoint of the target speed and the heat transfer. The paper is only focused on the heat transfer, and the heat conduction analysis is conducted for the conservative design. In this study, only the thermal conduction in the heat transfer analysis is considered for the HTS to be designed conservatively. If the force convection caused by the flow outside the reflector is considered, the maximum water temperature will decrease