Wake Characteristics of Ice-Accreted Cylindrical Bars in a Cross-Flow at Subcritical Reynolds Numbers

Abstract

Ice accretion can considerably alter aerodynamic characteristics of bridge cables. The present study focuses on flow characteristics in the cable wake for three arrangements of ice accretion on the cable surface. This is studied for the subcritical flow regime (subcritical Reynolds numbers) at various downwind distances of the cable. The analysis is based on velocity and force measurements carried out in a boundary-layer wind tunnel. Two different bridge-cable models are used, i.e., smooth cylinder representing dry cable, and artificially roughened cable representing ice-accreted bridge cable. The effects of ice accretion on flow characteristics in the cable wake are particularly exhibited when ice is oriented laterally downward for the cable section mounted horizontally in the wind tunnel. This is characterized by strong velocity reduction and turbulence enhancement in the cable wake.