Abstract:

Thermal environment in vehicle cabin is essential for occupant’s comfort, driving safety and reducing energy consumption. Focusing on the dynamic characteristics within a vehicle cabin in typical summer climate of South China, the experimental and numerical simulations methods are established. The steady and transition thermal environment parameters inside cabin under the effect of soaking and heating, ventilation and air conditioning(HVAC) system is measured and calculated. The “flow & heat” field of the steady and dynamic state as well as its influencing factors are investigated. The results show that the thermal environment in vehicle cabin is kind of typical “greenhouse effect”; and different positions have big differences in wall temperature caused by radiation intensity discrepancy; On the other hand, the air temperature inside the vehicle is highly non-uniform distribution and stratified evident along height direction owing to natural convection that rises by the temperature discrepancy; in the case where the car runs with the HVAC on, steady state of the air temperature is reached quickly within 10 min, while the wall temperature needs more than 30 min as the descent rate of wall temperature is much smaller than that of air temperature, therefore, it is still obvious non-uniform during the whole cooling period..

Key words: CFD, dynamic characteristics, experiment, thermal environment, thermal comfort