Optimal design for wind fence based on 3D numerical simulation

Abstract

Vegetative windbreaks and wind barriers are the two most important types of wind fences for controlling soil erosion by wind and are often used in combination. However, optimal configurations of wind fences have rarely been investigated, especially wind fences combining vegetative windbreaks and wind barriers. This study systematically explored the optimal configuration of the combined wind fence based on morphological observation data of wild Artemisa arenaria, Salix psammophila, and artificially planted Caragana korshinskii using three-dimensional computational fluid dynamics (CFD) technology. Furthermore, the airflow fields around wind fences were simulated using the shear stress transport(SST)k−ω Reynolds Average Navier Stokes (RANS) turbulence model in OpenFOAM. The effectiveness of different wind fences was compared in terms of the multiple barrier effectiveness index “mBEI” and a proposed index, downwind speed percentage “DSP”. The main findings are as follows: (1) The combined wind fence showed much higher shelter efficiency than either pure wind barriers or pure wild vegetative windbreaks. The shelter efficiency of the artificially planted Caragana windbreak was higher than that of naturally growing vegetative windbreaks irrespective of double-row or triple-row planting, and even exceeded that of the combined wind fence at higher wind speeds. (2) Regarding symbiotic wind fences with high-low shrubs, wind fences with a row of artificially planted shrubs showed higher shelter efficiency than those with pure wild shrubs. The shelter efficiency of wind fences was mainly determined by the morphological traits of plants and wind barriers. The results of this study can provide direct reference for practical sand control engineering.