高增益包层氚增殖率能够达到1.5以上，能量放大倍数约为5，包层燃料区平均功率达50 MW/m3，针对包层存在高功率密度区的这一特点，设计了采用迂回流动方案的水冷系统，主要由内嵌冷却管和汇总分流腔组成。建立了包括第一壁和燃料区的包层三维热工水力计算模型，利用CFD程序FLUENT对冷却系统进行模拟分析，研究了稳态工况条件下包层关键区域的整体热工水力特性。结果表明，该水冷系统流量分配合理，燃料区冷却剂压降为102 kPa，出口温度为594 K，符合设计预期。包层温度分布结果表明各区域最高温度均满足限值要求，冷却系统能够有效载出包层内裂变反应释放的热量。

The high breeding ratio blanket can obtain tritium breeding ratio over 1.5 and energy magnifying factor about 5, the fuel zone has power density more than 50 MW/m3 on average. According to the characteristic of high power density region in the blanket, this paper present the design of a circuitous flow cooling system, which is featured with inserted cooling tubes and the collecting-distributing manifolds. The thermal-hydraulic analysis has been conducted on this cooling system. A 3-D model consisting of the first wall and the fuel zone were established, the CFD code FLUENT were used to simulate the blanket under steady operating condition. As the numerical results show, this conceptual cooling system has a satisfying flow distribution, the pressure drop of coolant in whole fuel zone is 102 kPa, and the outlet temperature is 594 K, which meet the design expectation well. The maximum temperatures of all blanket structures are below the temperature limits, which indicates that the cooling system could carry the fission generated heat out effectively.