Numerical evaluation of the use of turbulence generators on the ampacity of overhead lines
Matheus Ungaretti Borges1; Alex Tomich Furtado1; Rudolf Huebner1; Geraldo Augusto Campolina França1; Carlos Alexandre Meireles do Nascimento2
1 UFMG; 2 CEMIG
doi:10.20906/CPS/COB-2015-1788
Resumo
An important object of study is how to increase the ampacity or the electrical current transport capacity of overhead transmission lines. However, the raise of electric current generates thermal energy by Joule effect and ferromagnetic ionization in the conductor. This results in higher wire temperatures considering constant climate conditions as ambient temperature, wind speed, intensity of solar radiation among other factors. The objective of this work is to build a computational model and use the finite volume technique to numerically evaluate the thermal effects from the use of unconventional geometries in energy cables with or without turbulence generators. Six wind speed conditions were simulated to the cross flow over geometry in each case. Comparing the numerical and the analytical results, the use of turbulence generators led to steady state with smaller wire temperatures in all cases and reduced the mean temperature from 6 % up to 12 %. By simply changing geometry, it was possible to enhance the maximum electrical current capacity and the ampacity, optimizing the process of supplying energy by reducing installation costs, maintenance and energy loss in overhead transmission lines. Thus, the benefits of using turbulence generators were noticeable from a thermal point of view.
Palavras-chave: Ampacity; CFD; Electrical Power Cable; Heat Transfer; Turbulence