Desarrollo de un modelo térmico de la cabina de un vehículo para predecir su comportamiento térmico bajo varias condiciones ambientales exteriores

Abstract

The objective of this degree work was to develop a dynamic thermal model of the cabin of a car, which allows estimating the variation of the interior temperature for a transitory process depending on the external conditions and the different thermal loads existing. In the first place, a bibliographic review of the different models was carried out. thermal sensors of cabins in vehicles, developed by different authors to establish the type of most suitable model. The model based its development on the heat balance method and was introduced in the Matlab programming platform to be able to integrate the different equations energy balance differentials obtained. The model was validated from trials experiments, with and without solar radiation, in which RMS values ​​of 1.11 and 0.57 were obtained - 0.74 as well as maximum temperature differences of 3.78 °C and 1.38 °C – 1.94 °C, respectively. The calculation of sensible heat was also carried out to determine the demand temperature that the air conditioning system needs to satisfy, to maintain thermal comfort inside the cabin. In addition, simulations of the behavior of the interior temperature in different conditions: changing the type of glass fitted, varying the number of occupants and considering three vehicle colors (black, yellow and white). The The results show that the temperature curves in the heating and cooling phase presenting the same trend for any duration time in the trials without incidence solar. Varying the color of the vehicle will reduce the absorption of dark colored vehicles warmer than those with light colors. The heat load is related to the number of passengers and the type of glazed surface, such as transparent glass, contributes to the reduction of the temperature in the cabin.