Ergonomic evaluation of thermal comfort for different outlet distribution patterns and ventilation conditions in the pilot protective helmet. (25th May 2023)

• Record Type: Journal Article
• Authors: Zhou, Xiaoli; Nie, Jiachen; Song, Bingqi; Yang, Qin; Xu, Xingxin; Xu, Jing; Zhang, Qing; Ding, Li
• Is Part Of: Applied thermal engineering. Volume 226(2023)
• Publication Date: 2023-05-25
• Subjects: Pilot protective helmet -- Ventilation -- Thermal comfort -- Head skin temperature; BTC Body thermal comfort -- ED Electronic device -- HH Head heating -- HTC Head thermal comfort -- HTS Head thermal sensation -- ODP Outlet distribution pattern -- WBH Whole body heating; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2023.120355
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: CFD and experimental methods were used to study head thermal comfort in pilot helmet. Head skin temperature dropped as the air pressure of ventilation increased. Head skin temperature dropped most under outlet distribution pattern B. Overall consistency was found between CFD and experimental results. Abstract: Ergonomic evaluation of thermal comfort is critical for heat stress alleviation systems in the pilot protective helmet, which is few investigated by existing approaches. In this study, CFD simulation under three ventilation pressure differences (60, 160, 260 Pa) and 4 outlet distribution patterns (ODP) was performed. Participants (n = 10) wearing the pilot protective helmet with a ventilation system were exposed to a constant thermal environment, while head skin temperature, subjective thermal sensation and comfort scales and relative humidity were measured. In simulation, head skin temperature changed oppositely to ventilation air pressure differences and increased due to the electronic module. Mean and maximum head skin temperatures were lower under ODP B and D. In experiments, head skin temperature was significantly lower after ventilation of 4 ODPs, while ODP B served optimal cooling effect. This study adds to the existing literature on head thermal comfort evaluation by extending the testing parameters and improving the testing accuracy.