【摘要】 在核反应堆堆芯中由于存在固有反应性反馈效应,会发生耦合反应性反馈流动不稳定性,对反应堆运行造成不利影响。本文采用实验与理论相结合的方法,研究了反应性反馈(包括空泡反馈、温度反馈)对流动不稳定性的影响。采用计算机仿真模拟反应性反馈,分别在没有核反馈和有核反馈的情况下进行实验,研究了空泡反应性反馈系数(C_α)、慢化剂温度反应性反馈系数(C_t)对流动不稳定性的影响。通过实验研究,获得了反应性反馈对流动不稳定过程的影响规律。研究表明,C_α、C_t和元件时间常数(f_t)对流动不稳定过程及流动不稳定边界都有较大影响。更多还原

【Abstract】 As the existence of nuclear feedback in nuclear reactors,coupled nuclear-thermo-hydraulic instability will occur in the reactor.Coupled-nuclear-thermal-hydraulic instabilities were investigated employing experimental and theoretical methods in this paper.The experimental research on coupled nuclear-thermo-hydraulic instability in parallel channels was performed and the effect of the nuclear feedback on flow instability has been studied.The experiment is carried out with and without nuclear coupled respectively,and the effect of void reactivity coefficient and temperature reactivity coefficient on characteristic and boundaries of flow instability has been studied.Based on the experimental data,the tendency of the characteristics of effect is analyzed,and the stability boundaries is obtained.The results from the research in this paper show that:void reactivity coefficient,temperature reactivity coefficient and fuel time constant have a significant effect on characteristics and boundaries of flow instability.更多还原