This paper examines the dynamics of steep to breaking standing waves on deep water generated by Faraday resonance. Physical experiments are compared with simulations by a two-dimensional spectral Cauchy-integral code. At larger forcing amplitude, we have observed experimentally a steep waveform with a double-peaked crest, while simulation of the same forcing condition results in a sharper crest (Jiang et al., 1996). Increasing wave steepness leads first to a double-plunging breaker at the dimpled crest, then to more violent breaking in three recurrent modes (period tripling): sharp crest with breaking (A) -> dimple or flat crest with breaking (B) -> round crest without breaking (C). Nonlinear interaction between the fundamental mode and second temporal harmonic determines both the steep and breaking waveforms. Geometric features of the breaking wave are discussed, especially the extremely-large wave amplitude and sharp crest angle in mode A. Based on the periodicity of the flow, energy dissipation is directly estimated by integrating the support force as a function of the tank displacement. It is found that the breaking event increases the total dissipation in the system by about 100percent. Large dissipation occurs during modes A and B due to spray, air entrainment and plunging.
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