The numerical wave channel has been developed based on the volume of fluid method (VOF) in conjunction with the Navier-Stokes equations. The absorbing wave-maker boundary on the left side of the channel is presented b...The numerical wave channel has been developed based on the volume of fluid method (VOF) in conjunction with the Navier-Stokes equations. The absorbing wave-maker boundary on the left side of the channel is presented by prescribing velocity reference to linear wave-maker theory. The principle of which is that the numerical wave-maker is designed to move in a way that generates the required incident wave and cancels out any reflected wave that reach it at the same time. On the right side of the channel, the open boundary is set to permit incident waves to be transmitted freely. The parametric studies have been carried out at a range of ratios of water depth to wave length d/ L from 0.124 to 0.219, with wave height in the front of paddle/water depth ratio (H0 / d) from 0.1 to 0.3. Wave height, wave pressure distribution along the channel and velocity field are obtained for both open boundary condition and reflective boundary condition at the other end of the channel. For a reflective case, it is shown that the absorbing wave-maker is very effective in canceling out the reflected wave that reaches the numerical paddle and highly repeatable waves can be generated.展开更多
The influence of the ultra-short pulse wavelength on the populations in the three electronic states of CsI molecule is investigated using the time-dependent wave packet method. The calculated results show that the pop...The influence of the ultra-short pulse wavelength on the populations in the three electronic states of CsI molecule is investigated using the time-dependent wave packet method. The calculated results show that the populations in the two excited states approach to the maxima at the wavelengths of 369 nm and 297 nm, respectively. The photodissociation reaction channels of the CsI molecule can be chosen by controlling the pump pulse wavelength.展开更多
电磁波随钻测量不受钻井液性质影响,因而优势得以突现,但其发展瓶颈在于信号传输距离短。论述了电磁波通道式MWD(measurement while drilling)传输装置信道计算的等效传输线法,分析了天线参数、激励源频率等参数的变化对检测电压的影响...电磁波随钻测量不受钻井液性质影响,因而优势得以突现,但其发展瓶颈在于信号传输距离短。论述了电磁波通道式MWD(measurement while drilling)传输装置信道计算的等效传输线法,分析了天线参数、激励源频率等参数的变化对检测电压的影响规律,并通过计算探讨了影响电磁波传输质量的因素。结果显示,地面检测电压随金属环长度增大而增大;温度是对电磁信号传输装置影响显著的一个参数,它能彻底改变电子元件的工作性能,使其丧失功能。因此,工程技术人员可利用等效传输线理论,合理地选择所用激励装置尺寸参数,从而达到优化天线尺寸的目的。展开更多
文摘The numerical wave channel has been developed based on the volume of fluid method (VOF) in conjunction with the Navier-Stokes equations. The absorbing wave-maker boundary on the left side of the channel is presented by prescribing velocity reference to linear wave-maker theory. The principle of which is that the numerical wave-maker is designed to move in a way that generates the required incident wave and cancels out any reflected wave that reach it at the same time. On the right side of the channel, the open boundary is set to permit incident waves to be transmitted freely. The parametric studies have been carried out at a range of ratios of water depth to wave length d/ L from 0.124 to 0.219, with wave height in the front of paddle/water depth ratio (H0 / d) from 0.1 to 0.3. Wave height, wave pressure distribution along the channel and velocity field are obtained for both open boundary condition and reflective boundary condition at the other end of the channel. For a reflective case, it is shown that the absorbing wave-maker is very effective in canceling out the reflected wave that reaches the numerical paddle and highly repeatable waves can be generated.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10674114 and 10604045)
文摘The influence of the ultra-short pulse wavelength on the populations in the three electronic states of CsI molecule is investigated using the time-dependent wave packet method. The calculated results show that the populations in the two excited states approach to the maxima at the wavelengths of 369 nm and 297 nm, respectively. The photodissociation reaction channels of the CsI molecule can be chosen by controlling the pump pulse wavelength.
文摘电磁波随钻测量不受钻井液性质影响,因而优势得以突现,但其发展瓶颈在于信号传输距离短。论述了电磁波通道式MWD(measurement while drilling)传输装置信道计算的等效传输线法,分析了天线参数、激励源频率等参数的变化对检测电压的影响规律,并通过计算探讨了影响电磁波传输质量的因素。结果显示,地面检测电压随金属环长度增大而增大;温度是对电磁信号传输装置影响显著的一个参数,它能彻底改变电子元件的工作性能,使其丧失功能。因此,工程技术人员可利用等效传输线理论,合理地选择所用激励装置尺寸参数,从而达到优化天线尺寸的目的。
