A classification system for non-ideal breaking waves

As any surfer will confirm, not all waves are created equal. Breaking ocean waves are grouped into four main categories: spilling, plunging, collapsing, and surging. Plunging waves have the iconic crest and barrel shape that draws in the surfers, but all four grab the interest of engineers designing ports, bridges, and other coastal infrastructure.

However, the metrics used to classify these waves tend to fail when applied to non-ideal gravity waves, such as tsunamis or breaking dams.

Haneesha Iphineni and Sharath Girimaji employed both 2D and 3D large eddy simulations to evaluate a series of dam-break waves impacting a submerged obstacle. Their goal was to develop a new set of classification metrics for non-ideal waves based on easily observable criteria.

“The traditional wave-breaking classification system is designed for ideal waves,” said Iphineni. “It relies on parameters such as wave steepness, height, and wavelength, which are difficult to define in non-ideal waves such as those generated by tsunamis or dam-break events.”

By analyzing their simulations, the authors identified several metrics, including horizontal particle velocity, surface particle trajectory slope, and acceleration magnitude, to classify waves. They redefined each type of wave using these metrics, offering a more reliable tool for evaluating the damaging potential of non-ideal waves.

The authors expect their results to benefit engineers designing coastal and offshore infrastructure.

“Improved breaker classification supports more resilient coastal protection systems, better designs for wave energy converters, and more accurate hazard prediction during extreme events such as tsunamis,” said Iphineni. “The study helps close the gap between laboratory models and real-world breaker dynamics, enabling engineers and scientists to develop effective solutions for complex coastal environments with greater accuracy and confidence.”

Source: “Wave breaking over submerged obstacles in gravity-driven dam-break flows: A classification framework,” by Haneesha Iphineni and Sharath S. Girimaji, Physics of Fluids (2025). The article can be accessed at https://doi.org/10.1063/5.0298764 .

This paper is part of the Wave-Structure Interaction Collection, learn more here .