一个新的破碎波统计模式

A NEW BREAKING WAVE STATISTIC MODEL

由运动方程和涡度方程所导得的两个首次积分估计给出了海波破碎的发生条件和破碎波的波面限制。由这两个条件所构造的新的破碎波统计模式,可导出海波的破碎面积率、破碎体积率和破碎能量损耗率的解析表达式,加之一个简单的白冠物理模型又导出了一个新的白冠覆盖率的解析表达式。

Through deriving two approximate first integral from the motion equation and the vorticity equation, this paper obtains the breaking condition of original wave surface and the formate of breaking wave surface. Based on these two results, a new breaking wave statistic model is derived. It depends on phase velocity, surface par-tical velocity of random wave as well as wind drift velocity of wave surface.In the case of narrow-band spectrum, joint distribution function of random phase velocity and random partical velocity is derived. Analytical expressions of breaking area, volume and energy loss are also derived, which depend on zero, first and second moment of wave spectrum as well as average surface wind drift velocity.Based on the above basic statistic and the defination of white cap, the coverage rate of white cap is obtained which is also related to wind drift velocity.