A Fundamental Study on Breaking Limit and Breaking Process of Multidirectional Random Wave.

本文主要通过室内试验研究了多向随机波场中潜堤的破碎极限和破碎过程。（1）在国际上首次研制出了具有12个电容式传感元件的破波仪，用于测量多向随机波的破波极限。破碎波计已被证明是非常强大的测量破碎的起始和破碎波。(2)相对破碎波高H_B/R（H_B ;破碎波高R ;波顶淹没深度）一般随扩展参数S的增大而减小<max>。(3)临界波陡H_B/L_*（L_* ;深水波长）公式为：H_B/L_* = 0.10 7 tanh（K_*R）其中，k_* 为深水波数。(4)相对破碎波高H_6/R的散射随扩展参数S_1的增大而增大<max>。(5)由于波浪的绕射和反射，潜堤侧端的破碎波高一般大于中部的破碎波高。

Breaking limit and breaking process due to the submerged breakwater, in the multidirectional random wave field, have been investigated mainly from laboratory experiments. The research results achieved are listed as follows :(1) The breaking wave gage with 12 electrical capacitance-type sensing elements has been newly developed, for the first time in the world, in order to measure the breaking limit of multidirectional random wave. The breaking wave gage has been shown to be very powerful to measure the breaking inception and breaking wave.(2) The relative breaking wave height, H_b/R (H_b ; breaking wave height, R ; submerged depth of crown) becomes smaller, in general, with increasing of the spreading parameter, S_<max>.(3) The critical wave steepness, H_b/L_* (L_* ; wavelength in deepwater) is formulated as,H_b/L_* = O.lO7tanh (K_*R)Here, k_* is the wave number in deepwater.(4) The scattering of the relative breaking wave height, H_6/R becomes larger, as the spreading parameter S_<max> increases.(5) The breaking wave height at the side-ends of the submerged breakwater becomes, in general, larger than that on the central part of the breakwater, due to wave diffraction and reflection.