A Numerical Study of Aerodynamic Characteristics of Ice-accreted Transmission Lines

Abstract

In this study, aerodynamic coefficients of single and 4 bundled ice-accreted conductors are investigated using LES turbulence model and compared with the results of the wind tunnel test. Single conductors with span length L=1D and 10D are simulated, and predicted aerodynamic coefficients with span length L=10D show favorable good agreement with the experiment within the estimated error range of the wind tunnel test. A systematic error estimation using the models with L=2D, 3D, and 6D is conducted and shows that the span length L=10D is long enough to predict aerodynamic coefficients. The effect of the accreted ice height, H, on aerodynamic coefficients is investigated. It is found that negative pressure at lower face near the leading edge significantly affects C_L and C_M　and causes maximum absolute value of C_L and C_M at 12° for the conductor with H=1D and at 16° for the conductor with H=0.5D. The wake effect of 4 bundled conductors is also investigated by the analysis of aerodynamic coefficients and pressure distribution for each conductor. The wake of windward conductors gives significant impact on C_L and C_M. Correction coefficients for leeward conductors are proposed to account for the wake effect, and the result shows favorable good agreement with predicted aerodynamic coefficients of 4 bundled conductors.