According to the theory of phononic crystals, the hydraulic pipeline is designed to be a periodic structure composed of steel pipes and hoses to suppress the vibration of the hydraulic system with band gaps. We presen...According to the theory of phononic crystals, the hydraulic pipeline is designed to be a periodic structure composed of steel pipes and hoses to suppress the vibration of the hydraulic system with band gaps. We present theoretical and experimental investigations into the flexural vibration transfer properties of a high-pressure periodic pipe with the force on the inner pipe wall by oii pressure taken into consideration. The results show that the vibration attenuation of periodic pipe decreases along with the elevation of working pressure for the hydraulic system, and the band gaps in low frequency ranges move towards high frequency ranges. The periodic pipe has good vibration attenuation performance in the frequency range below 1000 Hz and the vibration of the hydraulic system is effectively suppressed. A11 the results are validated by experiment. The experimental results show a good agreement with the numerical calculations, thus the flexural vibration transfer properties of the high- pressure periodic pipe can be precisely calculated by taking the fluid structure interaction between the pipe and oil into consideration. This study provides an effective way for the vibration control of the hydraulic system.展开更多
针对超(超)临界直流锅炉在降压吹管中传统的锅炉给水控制方法易造成机组主燃料跳闸的事故,提出以启动循环泵(boiler water circulating pump,BCP)出口流量作为控制点的给水控制方法。分析降压吹管过程中水冷壁与储水箱内工质的热力学变...针对超(超)临界直流锅炉在降压吹管中传统的锅炉给水控制方法易造成机组主燃料跳闸的事故,提出以启动循环泵(boiler water circulating pump,BCP)出口流量作为控制点的给水控制方法。分析降压吹管过程中水冷壁与储水箱内工质的热力学变化及流量测量原理,认为BCP出口流量能反映锅炉水冷壁及储水箱内的水量。通过理论计算得到降压吹管过程中的最小给水流量,总结出控制炉水循环泵出口流量不低于正常流量的60%,可以实现给水的优良控制。最后,将该给水控制方法成功应用于某电厂的吹管和主燃料跳闸过程,表明该方法具备实际工程应用性。展开更多
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
文摘According to the theory of phononic crystals, the hydraulic pipeline is designed to be a periodic structure composed of steel pipes and hoses to suppress the vibration of the hydraulic system with band gaps. We present theoretical and experimental investigations into the flexural vibration transfer properties of a high-pressure periodic pipe with the force on the inner pipe wall by oii pressure taken into consideration. The results show that the vibration attenuation of periodic pipe decreases along with the elevation of working pressure for the hydraulic system, and the band gaps in low frequency ranges move towards high frequency ranges. The periodic pipe has good vibration attenuation performance in the frequency range below 1000 Hz and the vibration of the hydraulic system is effectively suppressed. A11 the results are validated by experiment. The experimental results show a good agreement with the numerical calculations, thus the flexural vibration transfer properties of the high- pressure periodic pipe can be precisely calculated by taking the fluid structure interaction between the pipe and oil into consideration. This study provides an effective way for the vibration control of the hydraulic system.
文摘针对超(超)临界直流锅炉在降压吹管中传统的锅炉给水控制方法易造成机组主燃料跳闸的事故,提出以启动循环泵(boiler water circulating pump,BCP)出口流量作为控制点的给水控制方法。分析降压吹管过程中水冷壁与储水箱内工质的热力学变化及流量测量原理,认为BCP出口流量能反映锅炉水冷壁及储水箱内的水量。通过理论计算得到降压吹管过程中的最小给水流量,总结出控制炉水循环泵出口流量不低于正常流量的60%,可以实现给水的优良控制。最后,将该给水控制方法成功应用于某电厂的吹管和主燃料跳闸过程,表明该方法具备实际工程应用性。
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。
