异径管是电站锅炉汽水管道的重要组成部件。对比分析了中国、美国和欧洲3种标准中钢板焊制异径管的设计计算和强度校核方法,通过有限元计算对异径管局部应力分布进行了分析。结果显示,对于异径管的壁厚计算,不同标准的计算方法十分相近...异径管是电站锅炉汽水管道的重要组成部件。对比分析了中国、美国和欧洲3种标准中钢板焊制异径管的设计计算和强度校核方法,通过有限元计算对异径管局部应力分布进行了分析。结果显示,对于异径管的壁厚计算,不同标准的计算方法十分相近,计算结果相差很小,但是对于异径管与直管连接处的强度校核,不同标准的计算结果相差较大,ASME BPVC.Ⅷ-2017《Rules for Construction of Pressure Vessels》计算得到的异径管小端与直管连接处的补强厚度最大,GB 150—2011《压力容器》的计算结果略小于ASME BPVC.Ⅷ-2017《Rules for Construction of Pressure Vessels》的计算结果,而EN 13480-3-2012《Metallic industrial piping-Part 3:Design and Calculation》标准的计算结果明显偏小。有限元分析显示,无论在弯矩或内压条件下,小端接管处均有明显的应力集中,最大应力为小端最大应力的2.0倍左右。展开更多
The thermal hydraulic （TH） behavior of coo- lant water is a key factor in the structural integrity assessments on reactor pressure vessels （RPVs） of pressurized water reactors （PWRs） under pressurized thermal sh...The thermal hydraulic （TH） behavior of coo- lant water is a key factor in the structural integrity assessments on reactor pressure vessels （RPVs） of pressurized water reactors （PWRs） under pressurized thermal shock （PTS） events, because the TH behavior may affect the loading conditions in the assessment. From the viewpoint of TH behavior, configuration of plant equipment and their dimensions, and operator action time considerably influence various parameters, such as the temperature and flow rate of coolant water and inner pressure. In this study, to investigate the influence of the operator action time on TH behavior during a PTS event, we developed an analysis model for a typical Japanese PWR plant, including the RPV and the main components of both primary and secondary systems, and performed TH analyses by using a system analysis code called RELAP5. We applied two different operator action times based on the Japanese and the United States （US） rules： Operators may act after 10 min （Japanese rules） and 30 min （the US rules） after the occurrence of PTS events. Based on the results of TH analysis with different operator action times, we also performed structural analyses for evaluating thermal-stress distributions in the RPV during PTS events as loading conditions in the structural integrity assessment. From the analysis results, it was clarified that differences in operator action times significantly affect TH behavior and loading conditions, as the Japanese rule may lead to lower stresses than that under the US rule because an earlier operator action caused lower pressure in the RPV.展开更多
文摘异径管是电站锅炉汽水管道的重要组成部件。对比分析了中国、美国和欧洲3种标准中钢板焊制异径管的设计计算和强度校核方法,通过有限元计算对异径管局部应力分布进行了分析。结果显示,对于异径管的壁厚计算,不同标准的计算方法十分相近,计算结果相差很小,但是对于异径管与直管连接处的强度校核,不同标准的计算结果相差较大,ASME BPVC.Ⅷ-2017《Rules for Construction of Pressure Vessels》计算得到的异径管小端与直管连接处的补强厚度最大,GB 150—2011《压力容器》的计算结果略小于ASME BPVC.Ⅷ-2017《Rules for Construction of Pressure Vessels》的计算结果,而EN 13480-3-2012《Metallic industrial piping-Part 3:Design and Calculation》标准的计算结果明显偏小。有限元分析显示,无论在弯矩或内压条件下,小端接管处均有明显的应力集中,最大应力为小端最大应力的2.0倍左右。
文摘The thermal hydraulic （TH） behavior of coo- lant water is a key factor in the structural integrity assessments on reactor pressure vessels （RPVs） of pressurized water reactors （PWRs） under pressurized thermal shock （PTS） events, because the TH behavior may affect the loading conditions in the assessment. From the viewpoint of TH behavior, configuration of plant equipment and their dimensions, and operator action time considerably influence various parameters, such as the temperature and flow rate of coolant water and inner pressure. In this study, to investigate the influence of the operator action time on TH behavior during a PTS event, we developed an analysis model for a typical Japanese PWR plant, including the RPV and the main components of both primary and secondary systems, and performed TH analyses by using a system analysis code called RELAP5. We applied two different operator action times based on the Japanese and the United States （US） rules： Operators may act after 10 min （Japanese rules） and 30 min （the US rules） after the occurrence of PTS events. Based on the results of TH analysis with different operator action times, we also performed structural analyses for evaluating thermal-stress distributions in the RPV during PTS events as loading conditions in the structural integrity assessment. From the analysis results, it was clarified that differences in operator action times significantly affect TH behavior and loading conditions, as the Japanese rule may lead to lower stresses than that under the US rule because an earlier operator action caused lower pressure in the RPV.
