Research on thermal comfort of commercial vehicle and economy of localized air conditioning system with thermoelectric coolers

Abstract

In commercial vehicles, the power consumption of the traditional air conditioning system used to cool an entire cab is high. In most cases, there is only one driver in vehicle, so adjusting the local thermal environment around the driver can reduce much energy waste. In this paper, a localized air conditioning system based on thermoelectric cooling (TEC) devices was constructed, and its performance characteristic were studied to find the optimal operating conditions in practice. The relationship between the refrigeration power and the operating current of the device was studied. A bench test was carried out to evaluate the performance of the device and the accuracy of the simulation. This paper selected a commercial vehicle cab for the application of the TEC system. The thermal comfort of human body in cab and the economy of local air conditioning system was analyzed by the method of computational fluid dynamics. The driver’s thermal comfort was analyzed based on equivalent temperature and thermal comfort deviation. The results show that when the cooling power is 3000 W, the overall thermal comfort deviation of human body under local thermoelectric refrigeration is 7.94% higher than that under traditional refrigeration. When the duty ratio of the centrifugal fan governor is about 40%–60%, the semiconductor cooling device has excellent refrigeration performance and low energy consumption, which can not only ensure the thermal comfort of the driver but also reduce the energy consumption of the air conditioner.