高频焊接空冷器冷却管的研制

研制的３６ｍｍ×１４ｍｍ×１．５ｍｍ椭圆形高频焊接空冷器冷却管使用效果良好，为高频直缝焊管向多用途、高精度、高强度发展提供了经验。介绍了该产品的试制工艺及试制设备改进情况。高频焊接钢管，空冷器冷却管，研制     

Strategy evaluation for fire spray system on Advanced Passive PWR Severe Accident Management Guideline

The fire spray system (FSS) of the Advanced Passive PWR, as a part of the fire protection system, can provide a non-safety related containment spraying function for severe accident mitigation which is included in the Severe Accident Management Guidelines (SAMG) of the Advanced Passive PWR when dealing with severe accidents. The effectiveness of the FSS is investigated on three effects for severe accident mitigation which are controlling the containment condition, washing out fission product and injecting into the containment through three representative severe accident scenarios analysis with integral accident analysis code since there is no sufficient data support, besides the negative impact is also discussed. Results show that the FSS can be effective for controlling the containment condition, washing out fission product and injecting into the containment, however the effect is limited due to system limitation: the FSS can only cool the containment atmosphere for a short term; the flow rate of FSS cannot fulfill the success criteria given in the PRA report of the Advanced Passive PWR. Meanwhile, the hydrogen concentration and the containment water level should be the long-term monitored because actuating the FSS may cause hydrogen risk in the containment and containment flooding. Despite its limitation and negative impact, the FSS can be effective as an alternative severe accident mitigation measurement for postponing the process of accidents for safety system recovery.     

高强化柴油机气缸套周围冷却水流动的数值模拟和试验研究

针对柴油机的冷却进行精确计算，必须对柴油机内部流场进行深入的三维数值模拟和试验研究。首先分析了柴油机冷却水流动的数值模拟计算方法，建立了某柴油机气缸套周围复杂水腔的三维实体模型，并采用FIRETM软件对水腔模型进行计算，得到冷却水在缸套复杂水腔内的三维流场；再运用流量压力测量法和流动显示法对透明气缸套水腔内的冷却水流动进行试验。对比分析结果表明数值模拟计算的冷却水流动方向和流量大小与试验测量和观察结果相一致缸套水腔改进后冷却水的流量和压力分布合理，水腔内微涡和流动死区减少，缸套穴蚀减轻，此数值模拟方法是合理的。     

田湾核电站14C和3H年产生量估算

介绍了压水堆核电站堆芯燃料和冷却剂中14^C和3^H产生量的计算方法,计算了田湾核电站每年在堆芯燃料和冷却剂中产生的14^C和3^H的总活度,将该计算结果与俄罗斯在田湾核电站最终安全分析报告中给出的数据进行了比较分析,并从减少这两种核素产生量的角度提出了一些设计建议。     

Three-dimensional multi-phase numerical study for the effect of coolant flow field designs on water and thermal management for the large-scale PEMFCs

The multi-phase numerical study is performed for the large-scale proton exchange membrane fuel cells (PEMFCs) regarding coolant flow field design. In this study, three coolant flow fields were designed to explore the effect of different temperature distributions on the water management of the PEMFCs. The numerical results show that increasing the temperature gradient along the gas flow direction and improving the temperature uniformity perpendicular to the gas flow direction enhances PEMFC performance and makes the liquid water distribution in the gas diffusion layers more reasonable. The co-flow for the cathode gas stream and the coolant flow is beneficial to raise the temperature along the cathode gas flow direction and reduce the risk of flooding near the cathode outlet. Then, it is noted that the coolant flow field design is not necessary to keep the temperature absolutely uniform for the PEMFCs. Although increasing the coolant volume flow rate will reduce the IUT, it dramatically increases the risk of flooding near the cathode outlet. Therefore, the moderate volume flow rate is preferred. Finally, the effect of the coolant manifold on the volume flow rate uniformity in the coolant channels is investigated, and it is found that reducing the number of coolant channels is the best strategy to improve volume flow rate uniformity and thermal management performance.