低浓铀核热火箭发动机SCCTE堆芯物理特性初步研究  

Preliminary Study on Neutronic Characteristic of LEU NTR Reactor SCCTE Core

作　　者：赵润喆 霍红磊 ZHAO Runzhe;HUO Honglei(Division of Reactor Engineering Technology Research,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院反应堆工程技术研究部,北京102413

出　　处：《原子能科学技术》2021年第S02期221-227,共7页Atomic Energy Science and Technology

基　　金：中核集团“青年英才”项目。

摘　　要：使用低浓铀燃料是近年来空间核动力发展的重要趋势。本文采用蒙特卡罗程序MCNP对低浓铀核热火箭发动机代表方案SCCTE堆芯进行了物理特性研究计算。计算结果表明:该方案是一典型的热中子堆,初始剩余反应性和停堆深度满足正常运行需求;燃料分区富集优化后,径向功率变化较为平缓,轴向功率峰进一步上移,有利于提高氢气出口温度,从而提高比冲;燃料、慢化剂和反射层温度功率效应均为负值,满足设计要求;氢进入效应为正值,可以补偿部分温度功率效应。目前该方案缺乏掉落临界安全事故应对措施,在入水后有效增殖因数达到1.194,仍需要进一步改进。The use of low enriched uranium(LEU)fuel is an important trend in the development of space nuclear power in recent years.Based on this,the Monte Carlo program MCNP was used to calculate and analysis the neutronic characteristics of the representative space capable cryogenic thermal engine(SCCTE)core scheme for LEU nuclear thermal rocket(NTR)reactor.The calculation results show that this scheme is a thermal-neutron reactor,and the initial excess reactivity and shutdown depth meet the requirements of normal operation.After optimization of fuel zonal enrichment,the change of radial power is relatively gentle,and the axial power peak moves up further,which is beneficial to increase the hydrogen outlet temperature,thereby increasing the specific impulse.The temperature power effects of fuel,moderator and reflector are all negative values,which meet the design requirements.The hydrogen entry effect is positive,which can compensate for part of the temperature power effect.After entering the water,the effective multiplication coefficient reaches 1.194,which means the current scheme lacks measures for criticality safety as occurring launch accident.This still needs to be further improved.

关 键 词：SCCTE堆芯 低浓铀 核热火箭 MCNP程序 物理特性 

分 类 号：TL351.1[核科学技术—核技术及应用]