板状燃料组件流道部分堵塞的安全边界研究

为掌握板状燃料组件内多个流道堵塞下的流动换热特性，获得流动堵塞致传热恶化的触发边界，以提高板状燃料反应堆的运行安全性，以典型板状燃料堆JRR-3M的标准燃料组件为对象，基于定性分析将流道堵塞事故分为非相邻流道堵塞与相邻流道堵塞两类，采用计算流体动力学软件ANSYS Fluent对两类流道堵塞事故下的流动换热特性进行模拟。模拟结果表明:非相邻流道完全堵塞或相邻流道最大堵塞率低于35%，流道内不会发生局部沸腾且燃料最高温度低于许用温度。基于上述结果，可确定JRR-3M反应堆在堵流事故下的安全运行边界。

Safety boundary of flow channel partial blockage in plate-type fuel assembly

It is necessary to obtain the triggering boundaries of heat transfer deterioration by mastering the flow and heat transfer characteristics in plate-type fuel assembly with multiple channels blocked, to improve the operation safety of plate-type fuel reactors. Based on qualitative analysis, the flow channel partial blockage accidents can be divided into non-adjacent channel blockage accident and adjacent channel blockage accident for the standard fuel assembly of the typical plate-type fuel reactor JRR-3M. Furthermore, the simulations of the flow and heat transfer characteristics under the two types of accidents were carried out using the computational fluid dynamics software ANSYS Fluent. The simulation results show that local boiling will not occur in flow channels and the maximum fuel temperature will be lower than the allowable temperature when non-adjacent channels are completely blocked or the maximum blocking rate of adjacent channels is less than 35%. Therefore, the safety operation boundary of JRR-3M reactor under flow channel blockage accident can be determined.