AP1000核电厂第一跨空间内布置了设备冷却水系统(component cooling water system,CCS)驱动泵,能够保证核电厂事故工况下设备冷却水系统、余热排出系统等关键安全系统的正常运行,从而保证核电厂安全。然而在蒸汽发生器主给水管道双端断...AP1000核电厂第一跨空间内布置了设备冷却水系统(component cooling water system,CCS)驱动泵,能够保证核电厂事故工况下设备冷却水系统、余热排出系统等关键安全系统的正常运行,从而保证核电厂安全。然而在蒸汽发生器主给水管道双端断裂事故下,大量的水会泄放到第一跨空间内,对第一跨空间内的关键设备造成严重威胁。因此,对AP1000核电站蒸汽发生器主给水管道双端断裂事故下第一跨空间内泄放流体三维流动特性进行数值模拟。采用ANSYS系列软件,建立第一跨空间三维模型,基于流体体积模型(volume of fluid model,VOF)计算冷却剂喷放事故下,第一跨空间内流动特性及水位变化规律。计算结果表明,破口水从入口进入第一跨空间后在5.334 m层漫流,绝大部分泄放水通过该层设置的预留开孔流出,部分水在该层堆积。但是,由于设置挡水沿,泄洪水并未漫流到0 m层与-3.8 m层,随着冷却剂喷放引发给水泵跳泵,第一跨空间内水位将逐渐下降,不会造成重要设备防水台的漫流淹没。计算结果对核电厂主要泄洪途径、关键设备布置设计与优化提供了数值参考。展开更多
We collect seismic moment tensors of the earthquakes occurring from 1900 to 2013 in and around the Chinese mainland and summarize the surface ruptures and displacements of 70 earthquakes with M S≥7. 0. We divide thes...We collect seismic moment tensors of the earthquakes occurring from 1900 to 2013 in and around the Chinese mainland and summarize the surface ruptures and displacements of 70 earthquakes with M S≥7. 0. We divide these large earthquakes into three types. Type A contains earthquakes with surface ruptures and displacements. Type B is earthquakes without displacements and Type C is those without any of this data. We simulate a triangular distribution of displacements for Type B and C. Then,we segment these large earthquakes by using their displacements and surface ruptures. Finally,kinematic models are determined from earthquake data and Bicubic Bessel spline functions. The results show that,first of all,the reasonability and spatial consistency of defined models are advanced.Strain rates have better continuity and are comparable with geologic and geodetic results in Himalaya thrust fault zones. The strain rates decrease in the Tarim basin and the Altun Tagh fault zones because of their low seismicity. The direction of compressional deformation in Gobi-Altay is changed from SE to NE and its extensional direction is changed from NE to NW. The extensional deformation in the Ordos block is diminished obviously. Secondly,earthquakes account for 30- 50% of expected motion of India relative to Eurasia determined from the NUVEL-1A model,with a missing component of 20 mm / a which may contain aseismic deformation such as fault creep and folds,the missing parts of earthquake data and elastic strain energy released by potential earthquakes.展开更多
On April 20, 2013, the Lushan M^7.0 earthquake struck at the southern part of the Longmenshan fault in the eastern Tibetan Plateau, China. The shear-wave splitting in the crust indicates a connection between the direc...On April 20, 2013, the Lushan M^7.0 earthquake struck at the southern part of the Longmenshan fault in the eastern Tibetan Plateau, China. The shear-wave splitting in the crust indicates a connection between the direction of the principal crustal com- pressive stress and the fault orientation in the Longmenshan fault zone. Our relocation analysis of the aftershocks of the Lushan earthquake shows a gap between the location of the rupture zone of the Lushan Ms7.0 earthquake and that of the rup- ture zone of the Wenchuan MsS.0 earthquake. We believe that stress levels in the crust at the rupture gap and its vicinity should be monitored in the immediate future. We suggest using controlled source borehole measurements for this purpose.展开更多
Although there are many earthquake relics preserved in the southeast segment of the Ganzi-Yushu Fault in the central Tibetan Plateau,the recurrence regularity of paleoearthquakes is not yet clear.This work studies pal...Although there are many earthquake relics preserved in the southeast segment of the Ganzi-Yushu Fault in the central Tibetan Plateau,the recurrence regularity of paleoearthquakes is not yet clear.This work studies paleoearthquakes on this fault segment since the Holocene through geomorphic investigation and trench excavation.The results show that sinistral dislocation of the T3/T2 terrace boundary is up to 80 m at the Cuoa Township.A 1.5 m-high fault scarp extends 3 km near the Renguo Township.A number of paleoearthquakes are exposed in trenches at two places,respectively.In combination with historical records,our work has identified 5 or 6 paleoearthquakes on this fault segment since last 5600 years.The occurrence times and recurrence intervals of these paleoearthquakes are estimated by 14C dating on strata in the trenches.Our analysis shows that these paleoearthquakes do not exhibit evident periodicity,but instead show a clustering characteristic.From 5600 a to present,seismicity of the southeastern segment of the Ganzi-Yushu Fault has two active periods and one quiet period,and the present-day time is just in the second active epoch.The recurrence intervals of each active epoch are different:1000-1300 a in the first one,534 a in the second one.展开更多
文摘AP1000核电厂第一跨空间内布置了设备冷却水系统(component cooling water system,CCS)驱动泵,能够保证核电厂事故工况下设备冷却水系统、余热排出系统等关键安全系统的正常运行,从而保证核电厂安全。然而在蒸汽发生器主给水管道双端断裂事故下,大量的水会泄放到第一跨空间内,对第一跨空间内的关键设备造成严重威胁。因此,对AP1000核电站蒸汽发生器主给水管道双端断裂事故下第一跨空间内泄放流体三维流动特性进行数值模拟。采用ANSYS系列软件,建立第一跨空间三维模型,基于流体体积模型(volume of fluid model,VOF)计算冷却剂喷放事故下,第一跨空间内流动特性及水位变化规律。计算结果表明,破口水从入口进入第一跨空间后在5.334 m层漫流,绝大部分泄放水通过该层设置的预留开孔流出,部分水在该层堆积。但是,由于设置挡水沿,泄洪水并未漫流到0 m层与-3.8 m层,随着冷却剂喷放引发给水泵跳泵,第一跨空间内水位将逐渐下降,不会造成重要设备防水台的漫流淹没。计算结果对核电厂主要泄洪途径、关键设备布置设计与优化提供了数值参考。
基金sponsored by the Youth Fund of National Natural Science Foundation of China(41302171)National Natural Science Foundation of China(41372345)
文摘We collect seismic moment tensors of the earthquakes occurring from 1900 to 2013 in and around the Chinese mainland and summarize the surface ruptures and displacements of 70 earthquakes with M S≥7. 0. We divide these large earthquakes into three types. Type A contains earthquakes with surface ruptures and displacements. Type B is earthquakes without displacements and Type C is those without any of this data. We simulate a triangular distribution of displacements for Type B and C. Then,we segment these large earthquakes by using their displacements and surface ruptures. Finally,kinematic models are determined from earthquake data and Bicubic Bessel spline functions. The results show that,first of all,the reasonability and spatial consistency of defined models are advanced.Strain rates have better continuity and are comparable with geologic and geodetic results in Himalaya thrust fault zones. The strain rates decrease in the Tarim basin and the Altun Tagh fault zones because of their low seismicity. The direction of compressional deformation in Gobi-Altay is changed from SE to NE and its extensional direction is changed from NE to NW. The extensional deformation in the Ordos block is diminished obviously. Secondly,earthquakes account for 30- 50% of expected motion of India relative to Eurasia determined from the NUVEL-1A model,with a missing component of 20 mm / a which may contain aseismic deformation such as fault creep and folds,the missing parts of earthquake data and elastic strain energy released by potential earthquakes.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41174042, 41040034)the China National Special Fund for Earthquake Scientific Research in Public Interest (Grant No. 201008001)
文摘On April 20, 2013, the Lushan M^7.0 earthquake struck at the southern part of the Longmenshan fault in the eastern Tibetan Plateau, China. The shear-wave splitting in the crust indicates a connection between the direction of the principal crustal com- pressive stress and the fault orientation in the Longmenshan fault zone. Our relocation analysis of the aftershocks of the Lushan earthquake shows a gap between the location of the rupture zone of the Lushan Ms7.0 earthquake and that of the rup- ture zone of the Wenchuan MsS.0 earthquake. We believe that stress levels in the crust at the rupture gap and its vicinity should be monitored in the immediate future. We suggest using controlled source borehole measurements for this purpose.
基金supported by the Yushu Earthquake Science Investigation of China Earthquake Administration
文摘Although there are many earthquake relics preserved in the southeast segment of the Ganzi-Yushu Fault in the central Tibetan Plateau,the recurrence regularity of paleoearthquakes is not yet clear.This work studies paleoearthquakes on this fault segment since the Holocene through geomorphic investigation and trench excavation.The results show that sinistral dislocation of the T3/T2 terrace boundary is up to 80 m at the Cuoa Township.A 1.5 m-high fault scarp extends 3 km near the Renguo Township.A number of paleoearthquakes are exposed in trenches at two places,respectively.In combination with historical records,our work has identified 5 or 6 paleoearthquakes on this fault segment since last 5600 years.The occurrence times and recurrence intervals of these paleoearthquakes are estimated by 14C dating on strata in the trenches.Our analysis shows that these paleoearthquakes do not exhibit evident periodicity,but instead show a clustering characteristic.From 5600 a to present,seismicity of the southeastern segment of the Ganzi-Yushu Fault has two active periods and one quiet period,and the present-day time is just in the second active epoch.The recurrence intervals of each active epoch are different:1000-1300 a in the first one,534 a in the second one.
