Assessment of Thermal Comfort in a Car Cabin Under Sun Radiation Exposure

Abstract

The number of vehicles in Malaysia increases rapidly and these cars are usually parked at open or un-shaded parking areas due to limited roof parking facilities. Most of the car users need a few minutes to cool down the car cabin temperature because of the sun radiation exposure. The increase of car cabin temperature results in a degradation of the material and the interior quality of the car cabin and is also connected to the danger of heat strokes of passengers. Therefore, the objective of this study is to identify the temperature and relative humidity of the car cabin when it was exposed to hot and sunny days for the case of tropical climate. The data was collected in five different modes. It was observed for three days in order to reduce uncertainty. The results show that the car cabin temperature could be exceed to 60% from the ambient temperature when it was exposed to the sun within two hours and the relative humidity decreased from 25 to 54%.