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
文章根据并联同步开关电感收集(parallel synchronized switch harvesting on inductor,P-SSHI)技术,提出一种自供电的压电能量收集系统,实现了在低激励环境下的系统启动和电压输出功能,并基于压电材料分离电极理论设计冷启动电路。该...文章根据并联同步开关电感收集(parallel synchronized switch harvesting on inductor,P-SSHI)技术,提出一种自供电的压电能量收集系统,实现了在低激励环境下的系统启动和电压输出功能,并基于压电材料分离电极理论设计冷启动电路。该系统采用带有有源二极管的P-SSHI整流电路代替传统的整流结构,以减少整流过程的能量损耗,能够在动态范围内调节输出电压,实现多输出负载的功能。基于0.18μm CMOS工艺仿真结果表明,该系统的电压翻转效率达到85%,输出功率是采用传统整流电路的5.8倍,同时能够产生1.2、1.8 V 2种电压,用于不同负载供电。该自供电能量收集系统可用于解决物联网无线传感器网络节点的自供电问题。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.
文摘文章根据并联同步开关电感收集(parallel synchronized switch harvesting on inductor,P-SSHI)技术,提出一种自供电的压电能量收集系统,实现了在低激励环境下的系统启动和电压输出功能,并基于压电材料分离电极理论设计冷启动电路。该系统采用带有有源二极管的P-SSHI整流电路代替传统的整流结构,以减少整流过程的能量损耗,能够在动态范围内调节输出电压,实现多输出负载的功能。基于0.18μm CMOS工艺仿真结果表明,该系统的电压翻转效率达到85%,输出功率是采用传统整流电路的5.8倍,同时能够产生1.2、1.8 V 2种电压,用于不同负载供电。该自供电能量收集系统可用于解决物联网无线传感器网络节点的自供电问题。