%0 Journal Article
%T Finite Element Modelling of Electrical Overhead Line Cables under Turbulent Wind Load
%A Dominik Stengel
%A Milad Mehdianpour
%J Journal of Structures
%D 2014
%R 10.1155/2014/421587
%X This paper presents a finite element model of an overhead transmission line using so called cable elements which allow reproducing the cable¡¯s nonlinear characteristics accurately employing only a few elements. Aerodynamic damping is considered in the equation of motion by taking into account the relative velocity between the flow of the wind and the moving structure. The wind flow itself is simulated by wave superposition making necessary assumptions on the lateral correlation between the wind velocities along the cable length. As result from the simulation, the following conclusions can be drawn. The first natural frequency of generally used wide spanning cables lies well below 1£¿Hz where also most of the energy content of the wind excitation is to be expected. Aerodynamic damping is significant for the moving cables holding very low structural damping which leads to a suppression of resonant amplification. This is particularly of interest regarding the support reaction which is dominated by the mean value and the so called background response. The latter is mostly influenced by the randomness of the wind flow, especially lateral to the main wind direction. 1. Introduction Spanning over a few hundred meters, being light, and having slender structures, the wind acting on the cables contributes significantly to the overall loading of the suspension towers [1]. Both modelling of the cables and simulation of the acting wind field have to be undertaken with care to account for the particularities of such a horizontally expanded structure. Such specific features in modelling involve the nonlinear structure, the nonlinear equation of motion, and an adequate simulation of the acting wind. The last is more often described in its nature along and vertically to the main wind direction than in its lateral character which is more important for horizontally expanded structures. Many works have already dealt with this issue with different approaches, aims, and results. We start with early works [2] which gave a preliminary insight into the structural characteristics of overhead transmission line cables more than into the details of the wind excitation. Those works were soon followed by simulations [3] highlighting the importance of incorporating nonlinear effects and aerodynamic damping in regard to supporting reaction of suspended cables but without emphasizing the importance of the assumptions of the acting wind. Even in recent work, that aspect is not always included [4, 5]. Later studies on wind tunnel models [6] stress again the need of detailed analysis when
%U http://www.hindawi.com/journals/jstruc/2014/421587/