ON THE FORMATION OF THE BULGE IN A SPILLING BREAKING WATER WAVE

作     者：Wang, Zhongyuan Nadine, Aubry Jim, H.Duncan Wang Zhong-yuanThe 8th Department,Nanjing University (of Science and Technology, Nanjing 210094, P.R. ChinaNadine AubryThe Levich Institute and Department of Mechanical Engineering, The City College of theCity University of New York, NY 10031Jim H. DuncanDepartment of Mechanical Engineering, University of Maryland,College Park,MD 20742

作者机构：Nanjing Univ of Science and Technology Nanjing China 

出 版 物：《Journal of Hydrodynamics》 (水动力学研究与进展B辑（英文版）)

年 卷 期：1997年第9卷第3期

页      面：41-48页

核心收录：

学科分类：080704[工学-流体机械及工程] 080103[工学-流体力学] 08[工学] 0807[工学-动力工程及工程热物理] 0801[工学-力学（可授工学、理学学位）] 

主　　题：hydrodynamics,turbulence water wave,data analysis 

摘      要：The early stages of a spilling breaking water wave leading to the formation of a bulge on the forward face of the wave are investigated. In this study, simultaneous space-time measurements of the free-surface elevation of a spilling breaking water wave are recorded and analyzed. The analysis, carried out in the frame of reference moving with the crest of the wave,reveals that the formation of the bulge is due to the presence of a shock-like mode. In the previous frame of reference, the shock itself is unsteady but its (spatial) location is time independent and coincides with the toe of the bulge. As time increases, the shock undergoes a flip (a reflection symmetry) with respect to the midpoint of our time interval. Such a flip is responsible for an abrupt increase of the wave steepe-ness, which will lead to wave breaking at later times. Following these observations, we present a two-dimensional quantitative model which reproduces both the formation of the bulge and the sudden increase of the wave steepeness.