无限深水表面压力脉动产生的速度势与二阶绕射问题的辐射条件  

On the Velocity Potential Due to Pulsating Pressure Distribution on the Free Surface of Infinite-Depth Waters and the Radiation Condition for the Second-Order Diffraction Problem

作　　者：缪国平 刘应中[1] 

机构地区：[1]上海交通大学

出　　处：《水动力学研究与进展（A辑）》1989年第2期72-80,共9页Chinese Journal of Hydrodynamics

摘　　要：本文从集中压力脉动作用的特例出发,在严格的意义上得到了无限深水表面上延伸至无穷远处的非绝对可积的脉动压力分布作用下的二维和三维速度势解,并着重讨论了速度势的远方渐近形态和应满足的辐射条件。在普遍意义上证明了这时速度势应由强迫波动项、自由波动项和局部扰动项所组成,强迫波动项的辐射条件提法应与压力脉动的远方渐近特性一致。从而在理论上澄清了有争议的二阶绕射势辐射条件的提法问题。在此基础上给出了二维和三维情况中二阶绕射势应该满足的辐射条件。In the present paper, two-and three-dimensional velocity potentials generated by pulsating pressure distribution of infinite extent on the free surface of infinite-depth waters are strictly derived based on the special case of concentrated pulsating pressure. The far-field asymptotic behaviour of the potentials and the radiation conditions to be satisfied by them are discussed.It is proved in a general sense that the potential should be composed of forced wave component, free wave component and local disturbance component etc. and the radiation condition of the forced wave component should correspond to the far-field asymptotic behaviour of the pressure distribution. Hence, the formulation of radiation condition for the second-order diffraction potential has theoretically become clear. The radiation conditions for two-and three-dimensional problems are given in the paper.

关 键 词：水表面 压力脉动 速度势 绕射 辐射 

分 类 号：TV131.33[水利工程—水力学及河流动力学]