圆柱型结构内孤立波载荷实验及其理论模型  

INTERNAL SOLITARY WAVE LOADS EXPERIMENTS AND ITS THEORETICAL MODEL FOR A CYLINDRICAL STRUCTURE

作　　者：黄文昊[1] 尤云祥[1] 王旭[1] 胡天群[1] 

机构地区：[1]上海交通大学海洋工程国家重点实验室,上海200240

出　　处：《力学学报》2013年第5期716-728,共13页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家高技术研究发展计划(2010AA09z305);高等学校博士点基金(20110073130003)资助项目~~

摘　　要：在大型重力式密度分层水槽中,对内孤立波与圆柱型结构的相互作用特性开展了系列实验.基于两层流体中内孤立波的KdV,eKdV和MCC理论,建立了圆柱型结构内孤立波载荷的理论预报模型,给出了该载荷理论预报模型中3类内孤立波理论的适用性条件.研究表明,圆柱型结构内孤立波水平载荷包括水平Froude--Krylov力、附加质量力和拖曳力3个部分,可以由Morison公式计算,而内孤立波垂向载荷主要为垂向Froude--Krylov力,可以由内孤立波诱导动压力计算.系列实验结果表明,附加质量系数可以取为常数1.0,拖曳力系数与内孤立波诱导速度场的雷诺数之间为指数函数关系,而且基于理论预报模型的数值结果与系列实验结果吻合.Series experiments are conducted to investigate interaction characteristics of internal solitary waves with a cylindrical structure in a large-scale gravity type density stratified tank. Based on KdV, eKdV and MCC theories for internal solitary waves in a two-layer fluid of finite depth, a theoretical predicting model is established forinternal solitary wave loads on a cylindrical structure, and the applicability conditions for these internal solitary wave theories are presented in order to apply such a load predicting model. It is showed that the horizontal load on the cylindrical structure due to the internal solitary wave consists of the horizontal Froude-Krylov, added mass and drag forces, respectively, which can be determined by Morison formula, while the vertical load mainly is the vertical Froude-Krylov force which can be obtained from the dynamic pressure induced by the internal solitary wave. Results for series experiments show that the added mass coefficient can be taken to be a constant value of approximately 1.0, and there exists an exponential function relationship between the drag force coefficient and the Reynolds number based on the velocity field induced by the internal solitary wave. Moreover, the numerical results based on the theoretical predicting model have good agreement with experimental ones. The investigation provides a practical theoretical model for predicting internal solitary wave loads on marine engineering structures due to internal solitary waves on the basis of the series experiment results.

关 键 词：两层流体 内孤立波 圆柱型结构 内孤立波载荷 Morison公式 

分 类 号：O352[理学—流体力学]