Effect of Ambient Temperature Condition on the Temperature Distribution in Rail Car during the Operation of Heaters

초록

Abnormal change of weather is more frequently observed nowadays due to the climate change on the earth. Because extremely low or high temperature may cause discomfort of passengers, the rail car operators require excessive heating or cooling capacity, resulting in the consumption of more energy. In this study, the heating performance of rail car was studied under various ambient temperature<br>conditions in order to optimize the heating energy consumption and the thermal comfort of passengers. The ambient temperature was varied from -10 °C to +10 °C by using a real-scale environmental chamber for rail car, and the temperature change inside the car was monitored when the heating system was partially or fully turned on. It was found that the average temperature drastically increased upon the<br>operation of heaters, but it was saturated after 8 h. The vertical temperature distribution showed that the temperature was higher when the height from the floor was higher due to the movement of lighter warmed air moved to upward directions. However, the horizontal temperature distribution showed that there was no significant temperature distribution among front, mid, and back section. Based on<br>the obtained results, the needs of air mixing for getting more uniform temperature distribution was suggested in this study.