Multi-Zone Dynamic Modeling of Thermal Behavior in Vehicle’s Cabin for Comfort and Energy Saving 2019-01-5060

In the present work, the mathematical modeling of heat transfer in a vehicle’s cabin is investigated. The vehicle’s cabin temperature is one of the most important factors in accidents. Thus, it is not surprising that HVAC has a direct impact on the performance of occupants inside the cabin and especially the driver. Therefore, it is important to create a good thermal environment to provide thermal comfort for the driver and passengers. The focus of the current work is on mathematical modeling and analysis of the comfort conditions of the cabin. It is already hypothesized in this study that the gas behavior is ideal and the air properties inside the cabin depend on HVAC module air flow and controlled/uncontrolled leakage; the air in the cabin is appropriately mixed and no mechanical work is generated within the control volume. Effective thermal loads on the vehicle’s cabin are considered, including radiation, ventilation, ambient air, metabolic state, engine, exhaust, infiltration, and HVAC system, and changes in the temperature and relative humidity of the air of the cabin over time is reported, while the HVAC system is operating. Comparing the two modes of permanent and frequent intermittent infiltration of the ambient air into the cabin, it is observed that the amount of power consumed by the HVAC system is increased between 4% to 40% depending on the number of window opening per hour and infiltration of the air into the cabin. The best and the most appropriate time-cycle interruption of HVAC system in temperatures ranging from 19 °C to 26 °C in two modes of infiltration and non-filtration of the outdoor air into the cabin is obtained at 12 s. The position of temperature sensors inside the cabin is also studied and its effect on temperature uniformity is compared in three different modes.