Análise da viabilidade da concepção de um condicionador de ar automotivo utilizando módulos termoelétricos

Abstract

The objective of the study is to analyze the technical feasibility of an autonomous automotive thermoelectric air conditioner through thermoelectric modules, the Peltier effect. This effect arises due to an electromotive force existing in the union, originated by the different compositions of each union. Thus, the current can flow in both directions, but in one sense of the current the device absorbs heat from the surrounding medium and in the other radiates the heat absorbed into the environment. For the proposed experiment, six thermoelectric modules of aluminum oxide were used as ceramic material with 127 pairs of semiconductor material based on silicon. The tank used as a water reservoir in the experiment was fabricated using a thin sheet of iron and insulated with polyethylene foam coated with aluminum to avoid thermal losses to the medium. A common automotive evaporator unit was used for the process of heat exchange between the ice water and ambient air to be refrigerated. A digital thermometer with 5 test probes was used for the measurements of the water temperatures before and after the tank, as well as for the measurements of the ambient temperature and inside the workbench. For the drainage, an electric pump with power of 34 W was used, besides two switching sources of 12V / 25A. The air speed of the cooler installed in the evaporator unit is obtained by an anemometer and an infrared thermometer was also used. Already stopped water temperature was obtained through a digital hygrometer term. Initially, we expected more satisfactory results, but during the whole experimental phase we encountered several variables that were not included in the project. Therefore, although the results are somewhat different than expected, the prototype was able to reproduce satisfactorily the behavior of a thermoelectric cooling system in a vehicular air conditioner.