双排棒组件超临界水堆堆芯方案设计

结合国际上多种超临界水堆堆芯设计方案的优点,提出了一种新的压力容器式低泄漏堆芯设计方案,其特点是,堆芯中采用了双排棒正方形闭式燃料组件和三区低泄漏换料.双排棒燃料组件由两排燃料棒包围一个慢化剂水棒构成,可以使得慢化均匀；三区低泄漏换料可以大大延长堆芯寿期,降低压力容器快中子注量.通过堆芯三维物理热工耦合计算发现,该方案寿期内的最大包壳温度(MCST)为684℃,堆芯寿期为300个有效满功率天,且功率分布平坦.在此基础上,对所有组件进行了更为保守的子通道热工水力计算,得出MCST为685.3℃,进一步表明所提堆芯设计方案在物理热工方面是可行的.

Concept Design of Supercritical Water Cooled Reactor Core with Double-Row-Rod Assemblies

A new pressure-vessel type supercritical water cooled reactor(SCWR) core concept was proposed by combining merits of several SCWR core designs in the world.This core design employs a new type of closed assembly with double-row fuel rods in square geometry and a three-batch low-leakage refueling scheme.The assembly consists of two rows of fuel rods and a moderator rod,which causes the moderation more uniform.The three-batch low leakage refueling scheme obviously increases the cycle length and reduces the neutron fluence on the pressure vessel.Three-dimensional neutronics/thermohydraulics coupling calculation shows that the maximum cladding surface temperature(MCST) is 684 ℃,the cycle life is 300 effective full power days and the power distribution is flat.Then the more conservative sub-channel analysis was performed for all fuel assemblies.The MCST was evaluated to be 685.3 ℃,showing that the core design is feasible.