The Study On Surface Temperature Of Flame Engulfment Test During Cooling Phase

Thermal protective clothing is usually used to protect the workers who work under the hazardsituation, the surface temperature is still stay on a high level after getting rid of the fire exposure,and then this high temperature will transmit to human body through conduction, convection, andradiation. This kind of transmit will lead the body temperature rise and result in skin burning.This study focused on the relationship between clothing surface temperature to thermalprotective performance and body temperature and their influential factors based on flame manikinand thermal energy storage theory. Then, the surface temperature of clothing and body wereanalyzed and an empirical model between clothing and body temperature to time was exploredand optimized.The skin burning area percentage was used to represent the thermal protective performanceof the clothing, the correlation analysis between the percentage to clothing surface temperature,body temperature, and air gap was tested by using SPSS. The results showed the thermalprotective performance had a negative relationship with clothing and body surface temperature.The relationship between clothing surface and body temperature showed that the clothingsurface temperature had a obvious correlation to the initial and maximum temperature of body.But coefficient between clothing surface temperature and the maximum body temperature wasbigger, this meant that the clothing surface temperature had a great influence to the change ofbody temperature after fire exposure.Different factors of clothing, fabrics, body, and setting situation had been controlled to testtheir influence to clothing surface temperature. The result showed that the air gap made animportant role in the testing, the thinner the air gap was, the higher the clothing surfacetemperature was, and this trend would continue to influencing the body temperature. At the sametime, greater burning time and lower density and thickness would increase the clothing surfacetemperature, getting rid of fire burning would decrease the clothing surface temperature.After analyzing the clothing and body temperature, heat dissipation of clothing and bodyshould be happened during the cooling period. The Newton’s cooling law would be used to get the relationship between clothing temperature to time which is:T=Ce-kt+Tamb. The heat dissipation of body could be calculated at the body maximum temperature, heat conduction was firstly tried to study the relationship between clothing surface temperature and body temperature then make an empirical model. After comparing the experimental data, their relationship between body temperature to time empirical model had been optimized as follow: WhenWhen t≥t’In conclusion, the surface temperature of clothing, the thickness of the fabric, the air gap, the body temperature, and thermal protective performance had numerical relationship each other and this relationship showed low clothing temperature, thicker fabric, bigger air gap would result low body temperature and good thermal protective performance.