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Key research themes
1. How can depth-resolved morphodynamic models improve understanding of sediment transport processes in the swash zone at wave time scales?
This research theme focuses on the development, validation, and application of high-resolution, depth-resolved numerical models that simulate coupled hydrodynamics and sediment transport in the swash zone at the scale of individual waves or solitary wave events. Understanding sediment transport at these fine temporal and spatial scales is crucial for accurately predicting beach morphodynamics, given the swash zone's highly dynamic and rapidly changing nature. Such models aim to capture complex processes including turbulent flow structures, sediment suspension profiles, infiltration/exfiltration effects, and bed-level changes, which are difficult to observe experimentally due to scale and measurement constraints. These models contribute to enhanced prediction capabilities for beach erosion, accretion, and response to wave forcing, informing coastal management and hazard mitigation.
Key finding: This study presents a fully coupled 2DV morphodynamic model using RANS equations with a k−ω turbulence model and a Volume of Fluid approach to simulate solitary wave-induced swash morphodynamics. It highlights the importance... Read more
Key finding: Using stereoscopic optical methods in a large-scale wave flume, this study captures spatio-temporal bed-level changes over a 3×2 m swash zone area under random erosive wave conditions at high temporal and spatial resolution.... Read more
Key finding: This paper compares coupled and uncoupled hydro-morphodynamic numerical models simulating dam-break forced swash uprush. It reports that hydrodynamics calibrated well against experiments with about 10% tip celerity error,... Read more
Key finding: Employing a 2D numerical model solving volume-averaged RANS equations with turbulence closure and VOF method, this study examines how infiltration and exfiltration processes influence boundary layer dynamics in the swash... Read more
2. What are the spatiotemporal patterns and controlling factors of swash zone dynamics observed through high-frequency optical monitoring at microtidal, dissipative beaches?
This area investigates the use of high-frequency coastal video and optical monitoring systems to observe and quantify swash zone dynamics including shoreline position, wave run-up/run-down, and wave breaking locations, with a focus on microtidal, low-energy dissipative sandy beaches. It explores how wave energy, seabed morphology such as submerged sandbars, and hydrodynamic conditions influence alongshore and cross-shore variability, wave energy dissipation, and shoreline morphological responses. This research contributes to coastal management by providing accurate, high-resolution morphological and hydrodynamic datasets critical for understanding sediment transport processes and legal boundary delineations for coastal zone planning.
Key finding: Using a Beach Optical Monitoring System and in situ wave measurements over a winter period, this study reveals that increased wave heights cause offshore migration of the wave-breaking zone with significant alongshore... Read more
Key finding: By deploying autonomous coastal video systems and offshore wave loggers on a microtidal sandy beach, the study documents significant variability in shoreline positions and maximum wave run-up even under moderate wave... Read more
3. How do sediment characteristics and physical processes affect sediment transport dynamics and morphodynamics in the swash zone, especially regarding particle shape, size, and groundwater influences?
This theme examines how sediment properties such as grain size, shape, and permeability, together with hydrodynamic conditions and groundwater table variations, influence sediment transport pathways, erosion-accretion patterns, and boundary layer dynamics in the swash zone. It includes field experiments tracking pebble displacement and studies on infiltration/exfiltration effects on sediment mobility. Understanding these relationships is essential for predicting beach surface texture evolution, informing replenishment strategies, and improving models of sediment transport under varying environmental and climatic conditions.
Key finding: Using RFID technology to track individual pebbles on a mixed sand-gravel beach under low to moderate wave energy, this study shows that pebble shape and size influence displacement dynamics: discs move less but can cover... Read more
Key finding: Through field monitoring of tides, rainfall, groundwater table, beach profiles, and swash hydrodynamics at a Malaysian sandy beach, this study reveals that seasonal rainfall variations directly affect groundwater table... Read more
Key finding: The study's numerical modeling shows that infiltration of water into permeable beach sediments during uprush and exfiltration during backwash significantly influence flow velocity profiles, turbulence characteristics, and... Read more