Air flow dynamics in the cabin of a low-entry city bus

Abstract

The paper investigates the dynamics of air flows in the cabin of a low-entry city bus to improve passenger comfort and energy efficiency. The modeling was performed by CFD analysis in Ansys Fluent using the Mercedes-Benz Citaro Hybrid cabin model. Under winter conditions (flow inlet temperature – 27 °C, bus body walls – 0 °C), the maximum flow velocity reached 3.69 m/s in the doorway area, while insufficient ventilation was found in the front and rear parts of the cabin (velocity <0.8 m/s). It is recommended to introduce multi-flow ventilation with optimization of air supply angles by diffusers, as well as additional flows in the floor area to heat passengers' feet in winter (temperature < 290 K). The results obtained allow us to formulate effective solutions to improve the cabin microclimate and reduce discomfort zones.