共查询到16条相似文献,搜索用时 43 毫秒
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核电厂失水事故工况下,化学效应可能引起地坑过滤器过度堵塞,影响应急堆芯冷却系统或安全壳喷淋系统的再循环功能,导致堆芯、安全壳丧失冷却,威胁核电厂的安全。本文以秦山核电厂二期扩建工程为研究对象,开展失水事故工况下潜在化学产物对地坑过滤器压头损失的影响研究。结果表明,秦山核电厂二期扩建工程安全壳内含Al材料和保温材料在地坑环境中会析出Al、Si,Al、Si元素在地坑介质降温过程中形成了化学沉淀物,化学沉淀物会在地坑过滤器碎片床上沉积,堵塞碎片床流道,缩小碎片床孔隙率,导致地坑过滤器压头损失增加。因此,秦山核电厂二期扩建工程失水事故后存在化学效应,在地坑过滤器性能评估、下游效应分析中应予以考虑。 相似文献
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《Journal of Nuclear Science and Technology》2013,50(9):820-828
It has been a concern that sump screen clogging would occur in pressurized water reactors (PWRs) in the case of a loss-of-coolant accident (LOCA), because two-phase jet flow would strip off thermal insulation from the piping and wash down the broken and fragmented debris to sump screens. It is necessary for the evaluation of the effectiveness of sump screens to estimate the amount of transported debris from a break position to sumps. In general, conservative logic trees have been used to determine debris transport rates. Realistic debris transport evaluation is useful for considering measures and rational decision making in licensing. The purpose of this study is to develop a debris transport evaluation model and to apply the model to this issue. We developed a solid-liquid multiphase model that is capable of simulating debris transport, settling, and resuspension. The model is able to treat solid particles of different sizes, which are smaller than uniform-sized liquid particles. This approach contributes to reducing the calculation cost in a large-scale simulation. The model and a turbulence model were implemented into a code based on the moving particle semi-implicit (MPS) method. Several open-channel hydraulic experiments with fibrous debris were conducted. The code named SANSUI 2.0 was validated by the comparison of the analytical results with experiments. This method was applied to the debris transport analysis of a full-scale PWR containment vessel floor, and the debris transport behavior was evaluated. 相似文献
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核电厂地坑过滤器附加质量试验研究 总被引:1,自引:0,他引:1
采用测量转动惯量的方法对核电厂安全壳地坑过滤器水下附加质量进行测量,分别测量了圆柱、圆筒、双层圆筒、圆筒形地坑过滤器4种结构。将圆柱的附加质量测量值与在理想流体中的理论值进行对比,验证了该方法可以比较准确地测量附加质量。结果分析表明,附加质量不随激振频率变化,圆筒结构附加质量为圆柱结构的1.9倍,双层圆筒附加质量与单层圆筒差异不大;地坑过滤器由于表面开孔附加质量较圆筒结构降低70%;地坑过滤器附加质量与本身质量的值为同一数量级,地坑过滤器设计时不能忽略附加质量。 相似文献
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不符合项管理是质量保证管理中的一个重要组成部分,列举了核电厂在对不符合项管理中的实际做法;对不符合项管理的最终目的及其做法提出了管理见解。 相似文献
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某核电厂LOCA下预应力混凝土安全壳响应规律初探 总被引:2,自引:2,他引:0
核电厂LOCA发生后,预应力混凝土安全壳结构内温度场分布具有明显的非线性特征,但现行的混凝土安全壳设计规范未对LOCA下温度和应力的组合作用提出具体的计算方法。基于用ANSYS程序建立的包含预应力钢束的混凝土安全壳结构的有限元模型,本文计算了LOCA下不同时刻安全壳壳壁内的温度场分布,并与理论值进行了比较,验证了计算模型的正确性。初步分析了高温、高压作用下安全壳结构变形的规律,总结了混凝土温度效应和预应力系统的作用,可为安全壳结构设计提供参考。 相似文献