Cabin Comfort Improvement and Heating Energy Reduction under Cold-Condition by Using Radiative Heater

Since the regulations of CO2 emissions have been tightened in each country recently, each automotive manufacturer has responded by bringing competitive technologies that maximize efficiency while promoting vehicle electrification such as xEV. Not only the efficiency, we need to meet or exceed occupant performance and comfort expectations. The climate control system expends a large amount of energy to keep a comfortable environment, having a significant impact on fuel consumption and EV driving range. Therefore, many manufacturers try to save energy and improve occupant comfort quickly by using not only the conventional convective heating by HVAC but also the conductive heating to heat the human body directly such as seat and steering wheel heater. In this study, a radiative heater, which is more efficient than a convective heating to warm anterior thigh and shin where a conductive heating cannot warm, was applied to vehicle. The target performance was defined based on input heating energy to body and thermal sense throughout the experiments. The size and surface temperature of radiative heater were determined by CAE analysis to calculate the amount of input heat to body to meet the required performance. The radiative heater was integrated into the vehicle. Environmental chamber testing at the cold condition was performed to assess the heating and saving energy performance compared to a baseline conventional heating system. The experimental evaluations demonstrated that the heating energy was reduced by 5.3% with keeping same thermal sensation of whole body in steady-state period and improving it in thermal transient period.