An efficient resistance assessment method for the porous and upright roughness arrays

Sand fences and shelterbelts are often combined to form porous and upright roughness arrays (PURAs) to mitigate soil erosion and land degradation. However, the efficient resistance assessment for these massive arrays remains unresolved. This paper develops a novel method quantifying the resistance of the PURAs using computational fluid dynamics technology, which brings the drag term and the source term in the Navier–Stokes (N–S) equations to simulate the resistance of PURAs to airflow. Then, the equivalent boundary is conducted to accurately assess the drag coefficient of PURAs. Furthermore, the computational methods for the drag coefficients specific to sand fences and shelterbelts are presented, which are regarded as the functions of the porosity, the height, the number of belts, and the spacing of these arrays. Utilizing these insights, an efficient resistance assessment method is formed, with the threshold of wind pressure required to drive to sand movement serving as the evaluation criterion. Finally, the model's performance is validated against wind tunnel test results, demonstrating good accuracy. The findings show that the combination of sand fences and shelterbelts has a higher obstructive effect and the arrangement of shelterbelts in the narrow belt with multiple strips pattern can achieve higher resistance. This resistance assessment method of the PURA is superior to enhancing the design efficiency of sand and wind control engineering in intense wind-blown sand environments.