MOCKUP TEST AND SIMULATION FOR HEAT TRANSFER AND FLOW RESISTANCE OF HELIUM IN SUB-COOLING JACKET OF MODERATER CELL

摘要

Adding helium sub-cooling jacket to moderator cell of Cold Neutron Source (CNS) in China Advanced Research Reactor (CARR) is one of key techniques which can reduce the void fraction in liquid hydrogen zone. A mockup test rig was built to study the heat transfer and flow resistance of helium in the sub-cooling jacket. Nitrogen and helium with temperature of –30～0°C instead of cryogenic helium, liquid Freon instead of liquid hydrogen were used in the experiments. Heat transfer and flow resistance performances in operating condition of moderator cell are derived through numerical simulation. The conclusions provide useful evidences for the design of helium sub-cooling jacket in the moderator cell.