Estudio del desempeño de una bomba de calor para vehículos eléctricos en climas de la región Sierra ecuatoriana

Abstract

This work aims to study the performance of a heat pump (HP) for electric vehicles operating in the Ecuadorian highland region climates. It was implemented a thermodynamic model of the system, running several tests for its validation and subsequent simulation. The identification of preliminary data carried out for the modeling of the system was developed through a bibliographic review of similar studies. The model of the heat pump was implemented considering thermodynamic transformations within a cycle of vapor compression. Each component was modeled taking into account: size, efficiency, and capacity. The heating pump model was validated with the literature data. The model predicts the performance of a heat pump for various outdoor conditions. Simulations of the operation of the heating pump were carried out with an annual database of the outdoor and indoor temperatures of the vehicle. It was performed general simulations for eleven points corresponding to the hours when the heating system is mostly used, and also monthly simulations with the same points. Average seasonal performance was also calculated using the "bin hours" method, using the one-year outdoor temperatures of Quito city. A system optimization study was done by the variation of both subcooling at the condenser output and overheating at the evaporator output. There were found points where the system experiences a maximum COP. The results show that for general simulation at an outdoor nominal temperature of 13.89°C was obtained a COP of 3,594. If the heat pump worked consistently it would have an average annual yield of 3.8. Moreover, in monthly simulations, it was found different times where the COP takes high and low values at different hours of the day. Finally, it was found in the optimization an ideal subcooling and overheating of 7,332 K and 15 K respectively, for the nominal operating condition.