Modeling of batch distillation has been mostly based on equilibrium model in previous studies.It leads to a large-scale differential algebraic equations (DAEs) system.Due to its dynamic nature,initialization of the sy...Modeling of batch distillation has been mostly based on equilibrium model in previous studies.It leads to a large-scale differential algebraic equations (DAEs) system.Due to its dynamic nature,initialization of the system has been a problem.Batch distillation columns are frequently started up with different initial reboiler charges.A model to express startup behavior of batch columns starting from an empty cold state is proposed to handle this issue.Each tray will be described from a non-equilibrium phase in which only mass and energy transfer are taking place to an equilibrium phase in which the vapor-liquid equilibrium is reached.The switching point between these two phases is decided by the relationship of bubble-point temperature at the operating pressure.The liquid holdup of each tray is related to the geometry of the trays.The model is verified through experiment on a pilot batch plant with a bubble-cap tray column to separate a methanol-water mixture.展开更多
采用有限元方法,基于Block Lanczos算法和VonMises失效理论,考虑平台结构阻尼和惯性载荷,利用ANSYS有限元软件和开源程序软件FAST分别研究了平台安装角度对张力腿平台(Tension Leg Platform,TLP)结构应力的影响和振动响应。结果表明:在...采用有限元方法,基于Block Lanczos算法和VonMises失效理论,考虑平台结构阻尼和惯性载荷,利用ANSYS有限元软件和开源程序软件FAST分别研究了平台安装角度对张力腿平台(Tension Leg Platform,TLP)结构应力的影响和振动响应。结果表明:在极端海况下,张力腿平台海上漂浮式风力机受到的载荷及其运动响应主要集中在平台的纵荡、垂荡和纵摇方向,平台在重心初始位置做往复运动;波浪运动和平台耦合运动响应均不会引起平台发生共振作用;当风、波、流以相同入射角作用在风力机系统时,张力腿平台结构等效应力和最大切应力都随入射角的增大而增大;当风和波浪以0°入射角,海流以180°入射角作用时,平台的最大等效应力和最大切应力最小;张力腿平台安装角对平台应力有很大影响。展开更多
文摘Modeling of batch distillation has been mostly based on equilibrium model in previous studies.It leads to a large-scale differential algebraic equations (DAEs) system.Due to its dynamic nature,initialization of the system has been a problem.Batch distillation columns are frequently started up with different initial reboiler charges.A model to express startup behavior of batch columns starting from an empty cold state is proposed to handle this issue.Each tray will be described from a non-equilibrium phase in which only mass and energy transfer are taking place to an equilibrium phase in which the vapor-liquid equilibrium is reached.The switching point between these two phases is decided by the relationship of bubble-point temperature at the operating pressure.The liquid holdup of each tray is related to the geometry of the trays.The model is verified through experiment on a pilot batch plant with a bubble-cap tray column to separate a methanol-water mixture.
文摘采用有限元方法,基于Block Lanczos算法和VonMises失效理论,考虑平台结构阻尼和惯性载荷,利用ANSYS有限元软件和开源程序软件FAST分别研究了平台安装角度对张力腿平台(Tension Leg Platform,TLP)结构应力的影响和振动响应。结果表明:在极端海况下,张力腿平台海上漂浮式风力机受到的载荷及其运动响应主要集中在平台的纵荡、垂荡和纵摇方向,平台在重心初始位置做往复运动;波浪运动和平台耦合运动响应均不会引起平台发生共振作用;当风、波、流以相同入射角作用在风力机系统时,张力腿平台结构等效应力和最大切应力都随入射角的增大而增大;当风和波浪以0°入射角,海流以180°入射角作用时,平台的最大等效应力和最大切应力最小;张力腿平台安装角对平台应力有很大影响。
