A large eddy based lattice-Boltzmann simulation of velocity distribution in an open channel flow with rigid and flexible vegetation

Abstract

A b s t r a c tThe large eddy simulation method, based on a lattice-Boltzmann algorithm, was used to compute the vertical velocity profile in an open channel flow with submerged and emerged vegetation. The numerical method is characterized by the relatively short time of computation and low complexity. On the other hand, it allows a more realistic description of the vegetation properties relative to the methods commonly used in 1-D numerical models. For the proper conditions, the method developed in this work gives results similar to other numerical methods. These results are also in good agreement with the experimental data presented in other papers.

Large eddy simulation of the fluid–structure interaction in an abstracted aquatic canopy consisting of flexible blades

“…In fact, recurrence to simpler models is employed to alleviate the high cost for a full canopy mentioned above. Another numerical study addressing an entire canopy is (Gac 2014), but the agreement with the corresponding experiment is not as desired. The lack of numerical studies of canopies with flexible elements results from the fact that simulating a whole canopy with individual structures being resolved is methodologically very complex and requires an extremely efficient, tailored numerical method.…”

High-resolution numerical modelling of flow—vegetation interactions

“…Furthermore, the model was RANS-based and therefore unable to predict fully timedependent turbulence characteristics. Recently, Gac (2014) implemented a flexible vegetation model within a large eddy based lattice Boltzmann Model framework, which used a static version of the Euler-Bernoulli beam equation to calculate plant deflection (Kubrak et al 2008). This method reproduced mean velocity profiles well, however the treatment of plant motion did not account for inertial terms, solving only for a steady, static case at each timestep.…”

Integration of Submerged Aquatic Vegetation Motion Within Hydrodynamic Models

“…The development and improvement of methods for integrating individual SAV behavior within hydrodynamic models are required for carbon and nutrient budgeting and restoration decision–making at realistic field scales (Guan & Liang, 2017). At the individual plant scale, there have been several key studies where the movement and position of each leaf blade are modeled by considering the interaction with the current and wave (Abdelrhman, 2007; Dijkstra & Uittenbogaard, 2010; Gac, 2014; Kutija & Hong, 1996; Marjoribanks et al, 2014; Verduin & Backhaus, 2000). In Abdelrhman's (2007) eelgrass model, individual blades were divided into separate segments, each subject to drag force, lift force, friction force, and buoyancy.…”