A comprehensive description of the modelling methods will be presented, followed by an overview of significant publications on the topic. This review paper discusses the potential of CFD for simulating slurry pipe flows. The increase in computer power and the diffusion of multipurpose codes based on Computational Fluid Dynamics (CFD) have opened up the opportunity to gather information on slurry pipe flows at the local level, in contrast with the traditional approaches of simplified theoretical modelling which are mainly based on a macroscopic description of the flow. Slurry pipe transport has directed the efforts of researchers for decades, not only for the practical impact of this problem, but also for the challenges in understanding and modelling the complex phenomena involved. So, this work creates the basis to study more complex sediment transport processes such as erosion and sediment trapping in mangrove forests. With this successfully utilized approach, it will be possible in the future to investigate the impact of several mangrove seedlings forming a matrix on a m-scale on sediment dynamics. It is anticipated to extend the interactions between several seedlings as well as mangrove roots. This paper is an initial study focusing on a single mangrove seedling on a cm-scale. Additionally, these findings could help to better understand how the settlement of mangrove seedlings and sediment dynamics affect mangrove establishment and why the colonization or restoration of tidal flats is successful or not. Thus, a mangrove seedling has a significant influence on the flow pattern and sediment transport: the higher the flow speed, the less stable the sediment bed. The numerical simulations showed that a downward flow associated to a horseshoe vortex enhances scour in front of the mangrove seedling and a vortex shedding keeps the sediment in suspension or re-suspends the sediment in the rear of the mangrove seedling. This numerical model was validated against experimental observations and is able to capture the main features of the flow and sediment transport around a mangrove seedling. A natural mangrove seedling (Rhizophora mucronata) was digitized employing photogrammetry and discretized into the model domain. The distribution of the sediment phase in the water phase was estimated with the drift-flux approximation. The two phases, silty sediment and water, constitute a mixture. The hydro- and sediment dynamics were simulated using a coupled sediment-hydrodynamic continuum approach: the Finite Volume Method utilizing the software package OpenFOAM. s⁻¹ as well as a rarely occurring extreme scenario 50 cm.Four suits of numerical experiments were setup with the same mangrove seedling and subjected to flow speeds of 5 cm However, how a mangrove seedling (cm-scale) alters the flow pattern and the sediment transport is, to date, still poorly understood. To date we know that, in cohesionless sediment, the higher the flow velocity the greater the eroded volume and, thus, the stronger the scour around the mangrove seedling which can lead to its uprooting or death. It is widely accepted that the establishment, growth and survival of mangrove seedling depend on the environmental conditions such as temperature, tidal regime and hydrodynamics. Mangroves grow in the coastal and intertidal zones at tropical and subtropical latitudes. Using the proposed model, the transitional point from this lower to upper layer transport can be calculated precisely. For the hyper-concentrated profile, a clear division of lower (bed-load) to upper layer (suspended-load) transport can be observed in the measured data. Detailed comparisons reveal that the proposed model calculates the dilute profile with good correspondence to the measured data and other modelling results from literature. The proposed method has been shown to effectively compute the concentration profile for a wide range of suspended sediment conditions from hyper-concentrated to dilute flows. The accuracy of the proposed model has been verified against the reported laboratory measurements and comparison with other published analytical methods. A parameterised method combining the sediment size, Rouse number, mean concentration, and flow depth parameters has been used for modelling the sediment profile. Due to the differences between hyper-concentrated and dilute flows, a linear-power coupled model is proposed to integrate these considerations. This paper assesses the distribution of sediment for a variety of hyper-concentrated and dilute flows. During flooding, the suspended sediment transport usually experiences a wide-range of dilute to hyper-concentrated suspended sediment transport depending on the local flow and ground conditions.
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