CFBR-Ⅱ堆裂变率计算

Calculation of Fission Rate in CFBR-Ⅱ Reactor

为研究CFBR-Ⅱ堆裂变率的具体分布,建立了基于MCNP程序的裂变率计算方法,并利用国外高富集度铀裸球装置进行了验算。针对CFBR-Ⅱ堆实际结构的限制,设定了上下半球45o方向的虚拟孔道,沿此方向计算了裂变率的细致分布。结果表明,裂变率最大处位于高富集度铀区域中间某点,而非位于系统中心或上下半球球心。采用分布积分法进一步得到系统中心归一后的总裂变率为3 150.3,其中,贫化铀反射层贡献占5%。

In order to study the fission rate distribution in CFBR-Ⅱ reactor, the calculation method of fission rate based on MCNP is built and checking computations are conducted using the high enriched bare uranium sphere in foreign countries. The fission rate distribution in the top and bottom hemispheres in CFBR- Ⅱ reactor is calculated along virtual path setting at the direction of 45°. The results indicate that the maximum fission rate lies in neither the system center nor the hemisphere center but some place in the enriched uranium core. The total fission rate of center normalization in the reactor is calculated to be 3 150.3 by distribution integral method, in which the contribution of deficient uranium reflector is 5%.