Influence of porosity of reformed earth embankment windbreak wall on flow field and displacement of catenary under crosswinds

Abstract

Flow fields around reformed earth embankment windbreak walls (REEWWs) with five different porosities under crosswind were studied using the improved delayed detached eddy simulation (IDDES) based on the SST κ-ω turbulence model by computational fluid dynamics (CFD) in this paper. Based on the simulated flow field results, the finite element method (FEM) was adopted to analyze the wind-induced displacement of the catenary. The spatial dimensions of the five REEWWs were identical, but they had different porosities, with values of 0%, 12.5%, 25%, 37.5%, and 50%. The three-dimensional effects of the porosity on the flow structures and streamline patterns around the REEWWs and catenary, and wind-induced displacement of the catenary were investigated. The numerical algorithm used in this study was verified with the results from field tests. The results showed that installing a porous windshield on the top of the earth embankment windbreak wall will change the original flow structures. The windshield with a porosity of 37.5% reduced the wind speed around the catenary by 61.25% for line1 and 89.36% for line2, and the displacement of the catenary was reduced by 96.86%. Therefore, the protection performance of the catenary was improved. • Differences on the flow patterns around the windbreak wall and catenary were shown. • Velocities around the catenary under different porous windbreak walls were analyzed. • Turbulence intensity and gusts were investigated and compared. • Wind-induced displacements of the catenary were obtained and analyzed.