Large Eddy Simulation of Flow over a New Type of Low-Wind-Pressure Conductor Using WALE Model

Abstract

Associating with a grooved cylinder, our research group designs a new type of low-wind-pressure conductor. Based on the OpenFOAM v5.0 platform, five different types of three-dimensional low-wind-pressure conductors and the standard conductor are numerically simulated by using the Large Eddy Simulation with Wall-adapting local eddy-viscosity (WALE) SGS model at Re=1.4×105. Firstly, the flow around a circular cylinder is calculated to prove the reliability of computation in this paper. The calculation results are then analyzed for the comparison of the drag coefficient, flow field characteristics and surface pressure coefficient of the low-wind-pressure conductors and the standard conductor, respectively. The drag coefficient agrees well with the experimental value. The reason for drag reduction in low-wind-pressure conductors is proved to be the generation of small-scale vortices in the surface grooves, which delay flow separation and reduce pressure drag. By comparing the average drag coefficient of the five types of low-wind-pressure conductors, the rougher surface gives rise to a worse drag reduction effect.