Lattice Boltzmann method for the age concentration equation in shallow water

Zhong

Bao

et al. 2021

Water

Concerns have increased regarding water quality deterioration in arid land water. Water age is a useful indicator of the susceptibility of water bodies to water quality deterioration and is helpful for knowing the basic mechanisms governing the transport of materials through water bodies. In the current study, the spatial distributions of water age in the small lake of Bosten Lake (hereinafter referred to as small lake) were investigated with a two-dimensional hydrodynamic model built on the basis of the Environmental Fluid Dynamics Code (EFDC) model. In particular, the influences of different water flow periods, farmland drainages, and wind directions on water age distributions in the small lake were investigated. The modeled water age in the small lake has high spatial variability. The water age is maximum at the northeastern part and minimum at the center of the small lake. The water age in the small lake is lower during wet periods and gets larger for dry periods. After five years’ simulation, the average water age in the whole small lake system was 594, 684, and 794 days under wet, normal, and dry periods. Increasing the hydraulic connectivity of the small lake can reduce its water age by opening its ecological gate inflow and Ahongkou gate outflow. This is the more favorable hydraulic conditions promoting water exchange in most regions of the small lake and can be used in hydraulic engineering to improve its water age. The farmland drainages should be controlled around the small lake. The mean water age of the whole small lake under the northwestern wind is lower than that under the southwestern wind. The simulated results provide important information for comprehending the water exchange efficiency, help in discovery of areas of the small lake most likely to experience water quality degradation, and can be used to design the engineering projects to improve or protect the water environment.

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Diagnostic Simulation of Water Age in Small Lake of Bosten Lake

Zhong

Bao

et al. 2021

Water

“…Compared with traditional computational methods based on the direct approach of the flow equation, it proposes a new solution for the flow equation [18]. The method is characterized by simple calculation and easy handling of boundary conditions [19]. In recent years, it has become a promising approach in computational fluid dynamics [20].…”

Section: Introductionmentioning

confidence: 99%

Numerical Analysis of the Impact Factors on the Flow Fields in a Large Shallow Lake

Zhu

et al. 2019

Water

Self Cite

Wetland acts as an important part of climatic regulation, water purification, and biodiversity maintenance. As an integral part of wetlands, large shallow lakes play an essential role in protecting ecosystem diversity and providing water sources. Baihe Lake in the Momoge Wetland is one such example, so it is necessary to study the flow pattern characteristics of this lake under different conditions. A new model, based on the lattice Boltzmann method, was used to investigate the effects of different impact factors on flow fields, such as water discharge from surrounding farmland, rainfall, wind speed, and aquatic vegetation. Importantly, this study provides a hydrodynamic basis for local ecological protection and restoration work.

“…The lattice Boltzmann method (LBM) is a new numerical method to solve hydrodynamic problem. Compared with with traditional computational fluid dynamics (CFD) based on direct approach of flow equation, it proposes a new solution of flow equation [9]. The method is characterized by simple calculation, easy handling of boundary conditions.…”

Section: Introductionmentioning

confidence: 99%

Numerical Study of the Flow Fields in the Vegetated Baihe Lake

Zhu

2018

MATEC Web Conf.

Self Cite

Wetland is a multifunctional and biodiversity ecosystem on the earth, and it is also one of the most important living environments for human beings. Large shallow lakes play an important role in providing water and maintaining ecosystem diversity in wetlands. Vegetation growing in lakes and could affect the water flow by drag force. In the paper, a two-dimensional hydrodynamic model is developed and is applied to a large shallow lake, Baihe Lake in North China and the lattice Boltzmann method is selected as the simulation approach. The water velocity field of the lake is produced by the model and the distribution of the study area is investigated. Then, the hydrodynamic characteristics of lakes under different vegetation density are studied to find its influence on the water flow. This study provides a theoretical basis through a numerical tool for the administration of local hydraulic and ecological engineering.