Optimising the wave attenuation of bamboo fences using the numerical wave model SWASH

The coastline of Demak, Indonesia, has been eroding during the<br/>last 15 years. Coastal retreat in Demak is caused by a combination<br/>of mangrove deforestation and local subsidence due to groundwater<br/>extraction in the nearby city of Semarang. To restore the lost mangrove<br/>forest, permeable dams, consisting of bamboo poles with a<br/...

Non-Hydrostatic Modelling of Coastal Flooding in Port Environments

Understanding key flooding processes such as wave overtopping and overflow (i.e., water flows over a structure when the crest level of the structure is lower than the water level in front) is crucial for coastal management and coastal safety assessment. In port and harbour environments, waves are not only perpendicular to the coastal...

Simulation of 3D overtopping flow–object–structure interaction with a calibration-based wave generation method with DualSPHysics and SWASH

Ongoing climate change is a significant threat to coastal communities. To understand potential risks during extreme storm events, detailed post-overtopping processes are investigated using DualSPHysics and SWASH with a newly developed approach. It is a calibrated-based wave generation: a target incident wave is first obtained from the...

Numerical and small-scale physical modelling of wave transmission by wooden fences

Mangrove forests, that often act as natural coastal defences, enormously suffered due to ongoing climate change and human disturbances. Thus, it is necessary to have a countermeasure to mitigate the loss of mangroves. Wooden fences are becoming a viable nature-based solution to protect vulnerable replanted mangrove forests. However, the wooden...

On the accuracy of internal wave generation method in a non-hydrostatic wave model to generate and absorb dispersive and directional waves

The weakly reflective wave generation is a wave generation and absorption method in phase-resolving models, based on the assumption that the waves propagating towards the wave generation boundary are small amplitude shallow water waves with direction perpendicular to the boundary. This assumption makes the method weakly reflective for...

Benchmarking of numerical models for wave overtopping at dikes with shallow mildly sloping foreshores: Accuracy versus speed

Practitioners often employ diverse, though not always thoroughly validated, numerical models to directly or indirectly estimate wave overtopping (q) at sloping structures. These models, broadly classified as either phase-resolving or phase-averaged, each have strengths and limitations owing to the physical schematization of processes within...

An inter-model comparison for wave interactions with sea dikes on shallow foreshores

Three open source wave models are applied in 2DV to reproduce a large-scale wave flume experiment of bichromatic wave transformations over a steep-sloped dike with a mildly-sloped and very shallow foreshore: (i) the Reynolds-averaged Navier–Stokes equations solver interFoam of OpenFOAM® (OF), (ii) the weakly compressible smoothed particle...

Characterization of overtopping waves on sea dikes with gentle and shallow foreshores

Due to ongoing climate change, overtopping risk is increasing. In order to have effective countermeasures, it is useful to understand overtopping processes in details. In this study overtopping flow on a dike with gentle and shallow foreshores are investigated using a non-hydrostatic wave-flow model, SWASH (an acronym of Simulating WAves till...

Internal wave generation in a non-hydrostatic wave model

In this work, internal wave generation techniques are developed in an open source non-hydrostatic wave model (SimulatingWAves till SHore, SWASH) for accurate generation of regular and irregular long-crested waves. Two different internal wave generation techniques are examined: a source term addition method where additional surface elevation is...

Two-Dimensional Wave Overtopping Calculation over a Dike in Shallow Foreshore by SWASH

In this paper, a numerical wave-flow model SWASH, based on non-linear shallow water equation with non- hydrostatic pressure, is applied to the estimation of wave overtopping over a dike in shallow foreshores. First sensitivity analysis is conducted to see the influence of wave generation, grid size, time window and bottom friction by one...