HEATING AND COOLING TESTS OF URBAN TRANSIT CABIN USING A REAL-SCALE CLIMATIC CHAMBER

초록

Heating and cooling in urban transit cabin is getting more important because the thermal discomfort is one of the main reasons causing passengers complaints. For this reason, many urban transit operators have requested the climatic testing for newly manufactured proto-type train car before the mass production. In this study, results obtained from the climatic testing for an urban transit car manufactured recently. Temperature sensors were installed inside and outside of the tested car prior to the test. The ambient temperature was controlled to the desired temperature of -20 °C for heating test, and 34 °C for cooling test. The change in temperature during the operation of heaters or air-conditioner was monitored. One of the criteria requested by the operators is the uniform temperature distribution inside car during heating or cooling. The maximum allowed temperature difference for the same vertical or horizontal plane was 4 K, but the results showed more than 6 K. The reason for this large temperature difference is the incomplete mixing of air in the HVAC units. Several baffles were applied to obtain the better air mixing in the units, and the results showed that the temperature difference could be lowered up to 2.9 K. Through this climatic test, the problems with the car design could be found, and fixed before the mass production. More detailed results will be presented in this study.