Simulation of thermal comfort of a city bus using the PMV method using CBE Thermal Comfort Tool

Abstract

Today, the topic of vehicle microclimate is very relevant and does not stand still, because many scientists and engineers around the world are working on its improvements. Microclimate systems (heating, air exchange and air conditioning) provide comfortable transportation, so they are important and should be taken into account when designing their vehicle. The work of scientists from both Ukraine and abroad is analyzed in the work. The main research was conducted in the field of improving the heating, air exchange and air conditioning systems of buses, electric buses and trams and suburban trains. The main objectives of this study are to determine the importance of the driver's perception of thermal comfort in the cabin or cab (in the layout, when the driver is separated by a partition from the whole cabin). Also, taking into account metabolic processes in the human body, the theoretical value of metabolic thermal energy by the amount of oxygen consumed was calculated. Using the online program CBE Thermal Comfort Tool, PMV calculations were performed taking into account the main parameters of the microclimate according to ASHRAE standards and some diagrams were presented: psychrometric diagram of operating air temperature, psychrometric diagram of dry bulb temperature, humidity versus dryness diagram. thermometer, diagram of the dependence of air velocity on the operating temperature, diagram of the dependence of the components of heat loss on temperature and diagram of the dependence of heat loss parameters on temperature. Analyzing the regulatory framework of Ukraine on the selected topic, we can conclude that in Ukraine it does not exist as such, and the documents used are produced abroad or outdated. The results of this work can be applied to further research in the future. Based on further practical research conducted on the basis of the above theoretical work, it will be possible to analyze the thermal conditions in the cabin or cab of a particular bus and it will be possible to identify problem "points" for further discussion and further study.

Key words: microclimate, thermal comfort, PMV method, heat absorption, heat production, heat transfer.