The article aims at providing an up-to-date review on several latest advancements related to particle methods with applications in coastal and ocean engineering. The latest advancements corresponding to accuracy, stability, conservation properties, multiphase multi-physics multi-scale simulations, fluid-structure interactions, exclusive coastal/ocean engineering applications and computational efficiency are reviewed. The future perspectives for further enhancement of applicability and reliability of particle methods for coastal/ocean engineering applications are also highlighted.

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On the state-of-the-art of particle methods for coastal and ocean engineering

Particle methods in ocean and coastal engineering

Understanding the dynamics of sediment transport and erosion-deposition patterns in the locality of a coastal structure is vital to evaluating the performance of coastal structures and predicting the changes in coastal dynamics caused by a specific structure. The nearshore hydro-morphodynamic responses to coastal structures vary widely, as these responses are complex functions with numerous parameters, including structural design, sediment and wave dynamics, angle of approach, slope of the coast and the materials making up the beach and structures. This study investigated the sediment transport and erosion-deposition patterns in the locality of a detached low-crested breakwater protecting the cohesive shore of Carey Island, Malaysia. The data used for this study were collected from field measurements and secondary sources from 2014 to 2015. Sea-bed elevations were monitored every two months starting from December 2014 to October 2015, in order to quantify the sea-bed changes and investigate the erosion-deposition patterns of the cohesive sediment due to the existence of the breakwater. In addition, numerical modelling was also performed to understand the impacts of the breakwater on the nearshore hydrodynamics and investigate the dynamics of fine sediment transport around the breakwater structure. A coupled two-dimensional hydrodynamics-sediment transport model based on Reynolds averaged Navier-Stokes (RANS) equations and cell-centered finite volume method with flexible meshing approach was adopted for this study. Analysis of the results showed that the detached breakwater reduced both current speed and wave height behind the structure by an average of 0.12 m/s and 0.1 m, respectively. Also, the breakwater made it possible for trapped suspended sediment to settle in a sheltered area by approximately 8 cm in height near to the first main segment of the breakwater, from 1 year after its construction. The numerical results were in line with the field measurements, where sediment accumulations were concentrated in the landward area behind the breakwater. In particular, sediment accumulations were concentrated along the main segments of the breakwater structure during the Northeast (NE) season, while concentration near the first main segment of the breakwater were recorded during the Southwest (SW) season. The assessment illustrated that the depositional patterns were influenced strongly by the variations in seasonal hydrodynamic conditions, sediment type, sediment supply and the structural design. Detached breakwaters are rarely considered for cohesive shores; hence, this study provides new, significant benefits for engineers, scientists and coastal management authorities with regard to seasonal dynamic changes affected by a detached breakwater and its performance on a cohesive coast.

Dynamics of Sediment Transport and Erosion-Deposition Patterns in the Locality of a Detached Low-Crested Breakwater on a Cohesive Coast

Chlorine residual plays a key role in determining the quality of treated water and wastewater One of the most critical factors affecting chlorine decay rates is flow and ambient temperature Detailed knowledge of temperature impacts on the efficiency and performance of chlorine contact tanks will enable optimum design and operation of water and wastewater treatment infrastructures This paper develops a robust and computationally efficient three-dimensional numerical simulation model using Reynolds-averaged Navier-Stokes equations (RANS) with k - e turbulence closure model A non-reactive tracer transport model is developed by implementing three-dimensional advection-diffusion equation The Chlorine decay processes are simulated using Reynolds-averaged species transport model Temperature effects on density and viscosity is simulated through Millero and, Poisson and Vogel equations, respectively Eight scenarios with variation in inflow and ambient temperature are simulated in this study The residence time distribution (RTD) and hydraulic efficiency indexes are determined for the simulation scenarios It is shown that small fluctuation in inflow and ambient temperature cause a significant change in chlorine concentration and performance of disinfection tank The analysis of numerical simulations indicated that increase in ambient and inflow temperature can increase chlorine decay by up to 75 %, leading to undesirable disinfection consequences and disruption of water treatment processes The numerical model developed within this study was successfully validated against experimental measurements and it is shown to be robust and efficient tool to determine optimum inflow and ambient temperature configurations for high-efficiency water treatment processes and to prevent microorganism residual and by-products disinfection formation The computational framework presented in this study can inform optimum design of water and wastewater treatment processes

Modelling solute transport in water disinfection systems: Effects of temperature gradient on the hydraulic and disinfection efficiency of serpentine chlorine contact tanks

The paper presents a new numerical wave flume packaged as PARISPHERE code based on the Incompressible Smoothed Particle Hydrodynamics (ISPH) method with an improved framework for enhancement of the...

Development of PARISPHERE as the particle-based numerical wave flume for coastal engineering problems

A Lagrangian particle-based two-phase flow model is developed to simulate the scouring process induced by standing wave in front of the trunk section of a vertical breakwater. Given the two-dimensi...

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Lagrangian two-phase flow modeling of scour in front of vertical breakwater

In this paper, a two-dimensional Lagrangian model based on the weakly compressible smoothed particle hydrodynamics (WCSPH) was developed to explore the hydrodynamics of standing waves impinge on a ...

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Hamid Houshangi

Papers

Lagrangian two-phase flow modeling of scour in front of vertical breakwater

A Numerical Study on Hydrodynamics of Standing Waves in Front of Caisson Breakwaters with WCSPH Model