摘要
为研究核主泵在失水事故工况下气液两相瞬态流动变化规律,采用Euler-Euler非均相流模型,应用商业计算流体力学软件ANSYS CFX对核主泵内的气液两相瞬态流动特性进行数值模拟计算,分析了在失水事故工况下核主泵内部气液两相的不稳定流动的规律.结果表明:在流量变化过程中气相主要集中在靠近叶轮背面、导叶工作面区域内;气相所占比值变大使导叶内流速波动幅度向大尺度、无规律方向变化.流量变小时,出口回流对叶轮流道内气体体积分数变化产生主要影响;气相会改变导叶进口附近的流动变化趋势.流量变大时,进口气相区域向出口方向的延伸程度对叶轮流道内气体体积分数变化产生主要影响;气相会改变导叶流道出口附近流动变化趋势.流量变大与流量变小时,导叶内的气体体积分数变化趋势完全相反.在气相比值相同时,流量变小时叶轮内各监测点流速比流量变大时受气相的影响要大,故流量变大时输送汽液混合比有所提高.
To study the nuclear coolant pump variation rules in the gas liquid two-phase transient flow under the loss of coolant accident （LOCA） conditions, the computational fluid dynamics software AN- SYS CFX was applied. By using Euler-Euler non-homogeneous flow model, the numerical simulation result of gas-liquid two-phase transient flow characteristics in the nuclear coolant pump was obtained. The law of the gas-liquid two-phase instability flow based on the simulation under the LOCA condi- tions was analyzed. The results show that the gas phase is mainly near the impeller back and the vanes working face area in the process of variable flow. With the share of the gas increasing, the flow veloc- ity fluctuations in the vanes become large-scale and random. As flow becomes small, the reflow is the major impact on the gas volume fraction variation of the impeller outlet, and the flow trend near the guide vanes inlet is changed by the gas phase. As the flow becomes large, the extending degree of gas se area from import to export orientation is the major impact on the gas volume fraction variation he impeller outlet, and the flow trend closed to the guide vanes outlet is changed by the gas phase. en the flow gets large or small, the trend of the gas volume fraction inside the guide vanes is com- ely opposite. Under the same gas phase ratio conditions, as the flow turns small, the impact of gas phase on the velocity of each monitoring point in impeller is greater than the case of flow turns large. There[ore, the conveyed vapor-liquid mixing ratio is increasing with the flow getting large.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第9期112-116,共5页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家科技支撑计划资助项目(2011BAF14B04)
中国博士后基金资助项目(2012M521008)
江苏省自然科学基金资助项目(BK2011504)
江苏高校优势学科建设工程资助项目(PAPD)
江苏省博士后基金资助项目(1201024B)
关键词
核电站
失水事故
核主泵
两相流
气体体积分数
瞬态流动
nuclear power plant
loss of coolant accident~ nuclear main pump l two-phase flow
gasvolume fraction
transient flow
