[Paper Review] A Comparison of Measured and Predicted Wave-Impact Pressures from Breaking and Non-breaking Waves

Anne M. Fullerton, Thomas C. Fu+4 more|arXiv (Cornell University)|Oct 7, 2014

Ocean Waves and Remote Sensing10 references9 citations

TL;DR

This study compares measured wave-impact pressures from breaking and non-breaking waves against numerical predictions using data from a canonical experiment at the Naval Surface Warfare Center. It reveals significant discrepancies between predicted and measured pressures, particularly for breaking waves, highlighting limitations in current models for accurately estimating extreme impact loads on marine structures and vessels.

ABSTRACT

Impact loads from waves on vessels and coastal structures are complex and may involve wave breaking, which has made these loads difficult to estimate numerically or empirically. Results from previous experiments have shown a wide range of forces and pressures measured from breaking and nonbreaking waves, with no clear trend between wave characteristics and the localized forces and pressures that they generate. In 2008, a canonical breaking wave impact data set was obtained at the Naval Surface Warfare Center, Carderock Division, by measuring the distribution of impact pressures of incident nonbreaking and breaking waves on one face of a cube. This experimental effort was sponsored by the Office of Naval Research (ONR), under the Dynamics of Interacting Platforms Program, Program Manager Dr. Ron Joslin. The effects of wave height, wavelength, face orientation, face angle, and submergence depth were investigated. Additionally, a limited number of runs were made at low forward speeds, ranging from about 0.5 to 2 knots (0.26 to 1.03 m/s).

Motivation & Objective

• To evaluate the accuracy of existing numerical and empirical models in predicting wave-impact pressures on marine structures.
• To identify the influence of wave characteristics—such as wave height, wavelength, face orientation, and submergence depth—on localized impact pressures.
• To assess the effect of wave breaking on impact pressure distribution and magnitude compared to non-breaking waves.
• To examine the impact of low forward speeds (0.5–2 knots) on wave-impact loading behavior.
• To provide a benchmark dataset for validating future wave-impact prediction models in naval architecture and coastal engineering.

Proposed method

• Conducted controlled wave impact experiments using a cube-shaped model in a wave tank at the Naval Surface Warfare Center, Carderock Division.
• Measured spatial and temporal distributions of impact pressures using high-speed pressure transducers on one face of the cube.
• Varied wave height, wavelength, face angle, submergence depth, and forward speed to assess their effects on impact loading.
• Collected data under both breaking and non-breaking wave conditions to enable direct comparison between wave types.
• Used the experimental dataset to validate and compare predictions from existing numerical and empirical models.
• Analyzed pressure time histories and spatial pressure distributions to quantify peak pressures and load duration.

Experimental results

Research questions

• RQ1 How do measured impact pressures from breaking waves compare to those from non-breaking waves under similar wave conditions?
• RQ2 To what extent do current numerical and empirical models accurately predict the peak and spatial distribution of wave-impact pressures?
• RQ3 How do wave height, wavelength, face orientation, and submergence depth affect the magnitude and distribution of impact pressures?
• RQ4 What is the influence of low forward speeds (0.5–2 knots) on wave-impact loading characteristics?
• RQ5 What are the key discrepancies between predicted and measured pressures, particularly in breaking wave scenarios?

Key findings

• Measured peak impact pressures from breaking waves significantly exceeded predictions from existing models, indicating substantial underestimation of extreme loads.
• Non-breaking waves produced more predictable and consistent pressure distributions, whereas breaking waves exhibited highly variable and localized pressure spikes.
• The spatial distribution of impact pressures was strongly influenced by face angle and submergence depth, with higher pressures observed at oblique angles and shallower submergence.
• Wave height and wavelength had a nonlinear influence on peak pressures, with no clear monotonic trend across all conditions.
• At low forward speeds (0.5–2 knots), wave-impact pressures were generally lower but still showed high variability, especially in breaking wave cases.
• The canonical dataset revealed that current models fail to capture the full range of pressure dynamics in breaking wave impacts, particularly the rapid rise and high-magnitude peaks.