Wave Model and Wave Drift Caused by the Asymmetry of Crest and Trough

TL;DR

This paper introduces a new Lagrangian wave model that accounts for crest-trough asymmetry, providing a more accurate and rational description of wave drift, especially for waves with large slopes.

Contribution

A novel wave model incorporating crest-trough asymmetry, improving drift predictions without Taylor expansion, applicable to steep waves, and aligning well with particle velocity.

Findings

Depth-decay factor matches particle horizontal velocity

More rational than Stokes drift for large slopes

Provides accurate surface drift magnitude

Abstract

It follows from the review on classical wave models that the asymmetry of crest and trough is the direct cause for wave drift. Based on this, a new model of Lagrangian form is constructed. Relative to the Gerstner model, its improvement is reflected in the horizontal motion which includes an explicit drift term. On the one hand, the depth-decay factor for the new drift accords well with that of the particle's horizontal velocity. It is more rational than that of Stokes drift. On the other hand, the new formula needs no Taylor expansion as for Stokes drift and is applicable for the waves with big slopes. In addition, the new formula can also yield a more rational magnitude for the surface drift than that of Stokes.