改性涂料安全帽降温性能及热舒适的优越性分析

Superiority analysis of cooling performance and thermal comfort of safety helmet with optimized coating

为探究高温户外作业下改性涂料安全帽在我国不同地区的隔热降温效果差异,本文采用Fluent数值仿真技术结合我国4个不同地区(北京、广州、南京、西藏)的太阳辐射特性,对比研究了改性安全帽和普通安全帽的降温性能及热舒适性差异。结果表明:改性安全帽相比普通安全帽可使帽体表面温度降低10℃左右,同时帽内外部温差降低3~4℃,说明改性安全帽能够有效降低太阳辐射得热;对于4个不同地区,改性安全帽相比普通安全帽的帽内温度可降低5~7℃,并且当太阳辐射量大于1 200 W/m^(2)时,改性安全帽的降温性能愈发显著。进一步研究发现,相比佩戴普通安全帽,佩戴改性安全帽可使人体TEQ指数降低7.6%~9.6%,说明佩戴改性安全帽能够扩大作业者可从事体力劳动的工作范围,可提高户外安全帽佩戴者的热舒适性。

In order to investigate the difference of cooling effect of safety helmet with optimized coating in different regions of China under high temperature outdoor environment,combined with the solar radiation characteristics of the selected four regions of China(Beijing,Guangzhou,Nanjing and Tibet),the Fluent software is applied for studying the cooling performance and thermal comfort of the optimized and common safety helmets.The results show that safety helmet with optimized coating can reduce the surface temperature of the cap body by about 10℃ compared with the ordinary safety helmet,while the temperature difference between the inside and outside of the cap is reduced by 3-4℃.This phenomenon indicates that safety helmet with optimized coating can effectively reduce the heat gain from solar radiation.For the four difference regions,the internal temperature of the optimized helmet can be reduced by 5〜7℃ compared with the common safety helmet.Moreover,when the solar radiation is greater than 1200 W/m^(2),the cooling performance of safety helmet with optimized coating is more significant.Furthermore,wearing the modified helmet can reduce the TEQ index of human body by 7.6%〜9.6%compared to that of the ordinary helmet,which can expand the work range that the operator can do in physical work and thus improve the thermal comfort of the helmet wearers.