堆内辐照氚增殖剂球床有效热导率分析

氘-氚聚变反应堆中，固态氚增殖剂包层能不断为聚变反应提供氚核素，是实现聚变反应堆商用的关键技术之一。由锂陶瓷小球堆积形成的球床形式的固态氚增殖剂包层具有比表面积大、产氚效率高等优点，是我国重点发展的氚增殖剂包层形式。氚增殖剂球床须能支撑在堆内辐照时的高温环境，这就要求氚增殖剂球床有较好的导热特性。球床的有效热导率在球床设计和辐照过程中的安全分析十分重要，因此在中国先进研究堆（CARR）开展了氚增殖剂球床在堆内辐照环境下的有效热导率测量实验。根据MCNP计算得出的球床发热功率，结合实验测量的球床温度分布反推得到氚增殖剂球床的有效热导率，并与广泛应用于球床有效热导率计算的改进型ZBS模型计算结果以及堆外实验结果进行对比分析，理论值与实验值能较好吻合。

Analysis of Effective Thermal Conductivity of In-pile Irradiation Tritium Breeder Pebble Bed

The solid tritium breeder test blanket module (TBM) can constantly provide tritium for D-T reaction in the fusion reactor, and it is the key to realize fusion in business application. As the ratio of area to volume is large and the production efficiency of tritium is high, the development of the module made with ceramic lithium pebble beds is focused in China. The tritium breeder pebble bed should sustain the high temperature environment in the reactor, and this requires the pebble bed must have excellent thermal conductivity. The effective thermal conductivity of the pebble bed is important in the design phase and safety analysis phase of TBM. The irradiation experiment was carried out in China Advanced Research Reactor (CARR) to aim at measuring the effective thermal conductivity of the tritium breeder pebble bed. The effective thermal conductivity of the pebble bed was calculated with the heat generation power obtained with MCNP and the temperature distribution in the irrational experiment. The results of the calculation are shown to be in good agreement with the results obtained in the out of pile measurement experiment and theoretical results of the modified ZBS model.