Transient thermal performance of line traps

This paper develops a transient thermal model for line traps. The model was incorporated into a computer program that numerically integrates the governing nonlinear differential equation in time to predict critical temperatures and component short and long term ratings for a wide range of operating conditions. The model accounts for many factors including: variable air properties, variable material properties, environmental conditions, and a wide variety of component geometries and orientations. To verify the temperatures predicted by the thermal model, The Georgia Power Research Center carried out an extensive series of indoor laboratory tests to experimentally measure temperatures of energized line traps under transient loading conditions. Model predictions were within 8°C for 75 percent of the data. This paper presents the development of the governing equations and describes in detail the calculation of the convective and radiative components of heat transfer. Comparisons of the model predictions for two different line trap designs in different orientations to experimental data are presented to demonstrate the accuracy and flexibility of the thermal model