Calculation method for determining the heat loss of the air environment when opening the passenger vehicle cabin doors

Abstract

BACKGROUND: The microclimate in the bus cabin is of great importance in terms of both safety and comfort. The main parameters of the microclimate are temperature, humidity, dustiness and gassiness of the air, air exchange, the temperature of the elements of the interior surfaces and thermal radiation. AIMS: The article presents the results of calculating the heat loss in the air environment of the bus cabin using a mathematical model and experimental method. METHODS: The influence of different features of vehicle interior and exterior topology on the heat losses through the doors was estimated. The estimation of heat losses was performed using the ANSYS Fluent software package. The final result is to obtain the heat loss characteristics as a time-domain function. A field experiment was carried out to verify the obtained results. RESULTS: A set of numerical values and graphic characteristics giving an idea of the heat losses through the open doors of the bus cabin are presented. CONCLUSIONS: Due to the developed calculation method of determining the heat losses of the air environment, numerical values and graphical characteristics of the amount and intensity of time-dependent heat losses were obtained. The obtained results were verified experimentally. The study showed that the simulation in ANSYS Fluent and the field experiment have a discrepancy due to high values of the time constant of temperature sensors. In order to obtain the most accurate results, it is necessary to carry out the experiment with a time interval greater than the time constant.