Abstract
In Japan, cross-flow fans are installed in almost all commuter trains to circulate the air in a cabin and provide beneficial cooling to passengers, especially during the hot and humid summer seasons. The purpose of this study is to propose a method for predicting the passengers’ thermal comfort in non-steady state thermal environments with airflow from cross-flow fans in commuter trains in summer. The proposed method is composed of two calculation parts: one is a part for calculating sensory temperature based on a human thermoregulation model applicable to non-steady state thermal environments, and the other is a part for calculating the percentage of passengers dissatisfied with the thermal environment based on a statistical model derived from the results of experiments conducted in commuter trains in summer. In the proposed method, in order to evaluate the thermal comfort with a cyclic wind from cross-flow fans, the cyclic wind is converted to a constant wind keeping the total heat loss from the body calculated by human thermoregulation model. We examined the prediction accuracy of the proposed method by applying it to our previous research where fan-off/fan-on conditions and the congestion rates of below 100%, 120% and 180% were performed. As a result, the mean absolute prediction errors of the proposed method in the congestion rates of below 100%, 120% and 180% under fan-off condition were 9.4pt, 8.2pt and 7.3pt, respectively and those under fan-on condition were 4.5pt, 10.0pt and 13.2pt, respectively.
