摘要
Canopy architecture of windbreaks is vital in agriculture,meteorological and ecological applications.In this study,computational fluid dynamics(CFD) and field experiments were used to investigate the flow characteristics and flow resistance through vegetation canopies with several different leaf area densities(L_(ad)).Compared with traditional modelling approaches,the present model introduced 3D architecture of the tree that contained a hard trunk,branches and artificial leaves to model the effect of leaves and the other parts of the canopy on airflow.Visual basic application(VBA) produced the 3D architecture of canopy.Simulations were made with the full closure model(FCM) and microcosmic model(MM).Canopies L_(ad),used in the simulations were7.76,18.12 and 25.89 m^(-1).The objectives of this paper are to analyze the contour of velocity(U) and turbulent kinetic energy(k)of two models in different leaf area densities,comparing the simulation results with experimental data/other works and investigate the real effects of the canopy on the airflow distribution.Results are encouraging,compared with the FCM,V and k of MM profiles qualitatively agree better with other works.Therefore,the model and method are recommended for future use in simulating turbulent flows in forest canopies.
Canopy architecture of windbrpak is vital in agriculture, meteorological and ecological applications. In this study, computational fluid dynamics （CFD） and field experiments were used to investigate the flow characteristics and flow resistance through vegetation canopies with several different leaf area densities （ Lad ）. Compared with traditional modelling approaches, the present model introduced 3D architecture of the tree that contained a hard trunk, branches and artificial leaves to model the effect of leaves and the other parts of the canopy on airflow. Visual basic application （VBA） produced the 3D architecture of canopy. Simulations were made with the full closure model （FCM） and microcosmic model （MM）. Canopies L.~ used in the simulations were 7,76, 18, 12 and 25, 89 m-1. The objectives of this paper are to analyze the contour of velocity （U） and turbulent kinetic energy （k） of two models in different leaf area densities, comparing the simulation results with experimental data/other works and investigate the real effects of the canopy on the airflow distribution. Results are encouraging, compared with the FCM, U and k of MM profiles qualitatively agree better with other works. Therefore, the model and method are recommended for future use in simulating turbulent flows in forest canopies.
作者
王冰清
付海明
WANG Bing-qing FU Hai-ming(College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China State Environmental Protection Textile Pollution Control Engineering Technology Center, Donghaa University, Shanghai 201620, China)
基金
National Natural Science Foundation of China(No.41371445)
