Thermal comfort analysis of a high-speed train cabin considering the solar radiation effects

Abstract

Due to the fast development of high-speed rail (HSR) around the world, high-speed trains (HSTs) are becoming a strong competitor against airliners in terms of long-distance travel. Compared with airliner cabins, HST cabins have much larger window sizes. When the big windows provide better lighting and view of the scenery, they also have significant effects on the thermal conditions in the cabins due to the solar radiation through them. This study presents a numerical study on the solar radiation on the thermal comfort in a typical HST cabin. The effect of solar radiation was discussed in terms of airflow pattern, temperature distribution and thermal comfort indices. Parametric studies with seven different daytime hours were carried out. The effect of using the roller curtain was also studied. The overall cabin air temperature, especially near passengers, was found to have significantly increased by solar radiation. Passengers sitting next to windows were recorded to have an obvious thermal comfort variation at different hours of the day. To improve the passengers’ comfort and reduce energy consumption during hot weather, the use of a curtain could effectively reduce the solar radiation effect in the cabin environment.

Air Flow Experiments on a Train Carriage—Towards Understanding the Risk of Airborne Transmission

“…Of course, the distribution of the airborne pathogen within the vehicle can depend on the location of the infectious individual. The heating of surfaces by solar radiation can also affect airflow within the vehicle on sunny days [14,15,19]. Furthermore, the movement of people has been shown to have a considerable impact on the mixing of airborne contaminants indoors [20] and is likely to play a significant role in vehicles, particularly during busy periods.…”

“…An understanding of the outdoor air provision in addition to the airflow patterns within public transport vehicles is, therefore, essential in order to effectively mitigate the risk of airborne transmission. The literature on airflow patterns within buses and trains is focused mainly on assessing the thermal comfort of passengers, e.g., [14][15][16][17][18][19]. In [21,22], respiratory droplet transmission within a train carriage is modelled using Reynolds-Averaged Navier-Stokes (RANS) computational fluid dynamics (CFD).…”

Indoor thermal climate after energy efficiency measures of a residential building in a sub-Arctic region: Comparing ANSYS CFX and IDA ICE methods

“…Using CFD software such as the ANSYS CFX to investigate the indoor thermal climate in full 3D environments with PPD has been shown to be possible. 21,22 Using a finite volume method such as in ANSYS CFX, each volume is evaluated separately, representing the local thermal climate. By evaluating all of the finite volumes in a room, asymmetries, such as thermal radiation, can be seen and estimates for whole-body thermal sensations would be possible.…”

Modeling disease transmission in a train carriage using a simple 1D ‐model

“…Similar work has been conducted to evaluate the ventilation in trains. Both thermal comfort [15][16][17][18][19] and aerosol distribution 18 have been studied within railway carriages using CFD. Measurements have been conducted by Shinohara et al 20 to estimate the air-exchange rates and to evaluate the airborne infection risks using CO2 decay methods within a naturally ventilated commuter train.…”