【摘要】 在 5MW低温堆的模拟试验台架 HTRL- 5上对该低温堆上空腔破口失水事故进行了实验研究。重点研究了事故后期的流动振荡现象，揭示了振荡的发展过程和发生机理。经实验研究，给出了小破口失水闪蒸过程中回路内压力、温度、空泡份额、循环流量等重要参数的变化规律，同时表明了小破口失水过程中由于压力下降引起闪蒸产生大量气泡并引起自然循环流量的变化，这些变化又反过来对各参数产生影响，使循环流量和传热情况发生周期性变化。更多还原

【Abstract】 Experimental results of flow oscillation under small break loss- of- coolant accident(sbLOCA) on upper plenum of nuclear heating reactor are presented in this paper.The experiment is carried out on the thermohydraulic test system HRTL- 5 of the 5MW nuclear heating reactor,which is a natural circulation system.The variations of pressure,temperature,void fraction,and circulation mass flow are described.Flow oscillation is described and its development mechanism is studied specially.Results show that the pressure decreasing in LOCA and bubbles producing caused by flashing,and mass flow variation have influence on each other and cause cyclical variations of flow and heat transfer.更多还原