Implementation of a consistent co-rotational nonlinear dynamic formulation and application to modeling overhead transmission lines.

Abstract

The overhead transmission lines are frequently affected by severe climate events such as thunderstorms or heavy snowfalls. Such events might cause the disconnection of the line, with potentially severe consequences. In the period of 2000- 2007, more than twenty events of disconnection were registered in one of the main transmission lines in Uruguay. Given the particular features of local winds and temperatures, solutions applied in other countries might not be applicable. This demonstrates the necessity to develop numerical models to enhance the prediction capabilities of these events, guaranteeing in that manner a continuous supply of energy. The Universidad de la Republica (UdelaR) counts with research groups working on this problem. The Computational Fluid Mechanics Group (GMFC) is working, since 2004, in the development of computational models of tridimensional fluxes for various applications. The main code developed is called caffa.3d.MBRi and it’s based on the Finite Volume Method, using MPI parallelization. The group called Modelling and Identification in Solids and Structures (MISES) is committed, since its creation in 2018, to the development of numerical codes for structural analysis. The main code developed is called Open Non-linear Structural Analysis Solver (ONSAS) and it is publicly available. In this work a reference formulation for consistent non-linear dynamic analysis of beam structures using a co-rotational approach is implemented in the ONSAS code. The authors are not aware of any other open implementation of this formulation available. The implementation is validated using reference problems and also applied to the modelling of high voltage transmission lines considering realistic geometries and loadings.