Laboratory Studies of Steep and Breaking Deep Water Waves in a Convergent Channel
Abstract
In the present experiments, waves were made to steepen by a convergent section which was installed in NRL's 30m long wave channel. These and other recent experiments have demonstrated that a criterion for the onset of breaking for deep water waves can be simply stated in terms of the wave steepness at breaking. This criterion states that the wave steepness at the onset of breaking is given by H/L* = approx. 0.11, where H is the wave height and L* is the Stokes limiting wavelength. On the evidence available thus far the simple steepness criterion applies equally well to spilling and plunging breakers. Criteria such as this can be readily used to predict the frequency of occurrence of breaking for deep water waves. There are more complex questions relating to energy losses in breaking and related topics which cannot be addressed so simply. From the results of the present experiments it appears that the potential energy loss rates of plunging breakers are twice those of spilling breakers in deep water. Moreover, the potential energy losses in breaking did not significantly alter the total mean drift and return flows in the channel. Most of the energy lost goes into the production of turbulence and into air entrainment in the breaking region. Keywords: Wave breaking; Ocean waves; Ocean engineering.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 21, 1985
- Accession Number
- ADA158187
Entities
People
- M. E. Barber
- O. M. Griffin
- S. E. Ramberg
Organizations
- United States Naval Research Laboratory