T型管热混合温度波动特性研究

Experiment Study on Temperature Fluctuation Characteristics of Two-phase Thermal Mixing in T-junction

在反应堆发生失水事故(LOCA)时,一回路系统压力降低,产生大量蒸汽,堆芯应急冷却系统(ECCS)启动后,安注水注入冷腿后在T型管处与蒸汽发生热混合,温度会出现明显波动,同时伴随有一定的回流。本文以T型管中冷热流体混合为研究对象,开展了安注过冷水与冷腿中的饱和蒸汽热混合实验。研究内容主要为过冷水与饱和蒸汽在水平T型管发生热混合之后的水跃和回流现象,基于动量分析的方法,分析了不同流型对热混合后温度分布的影响,提出了两相流动量比关系式用于分析T型管内温度波动特性。

During the process of loss of coolant accident（LOCA）in a PWR,the system pressure of primary circuit will decrease and great amount of vapor will be generated.The cooling water in the accumulator was poured into the cold leg after emergency core cooling system（ECCS）started,accompanied with temperature fluctuation and back flow phenomenon.The research was focused on thermal mixing in T-junction in ECCS and based on the experiment between subcooled water in the safe injection and saturate steam in the cold leg.The main part of this research was dedicated to obtain the effects of hydraulic jump and back flow on T-junction thermal mixing.The analyses about temperature fluctuation in the T-junction,which were based on momentum method,wereattempted to find the influence of different flow patterns on the temperature distribution and a correlation to analyzing the temperature fluctuation on thermal mixing was proposed.