Survival Time of Humans in Extreme Cold Climate: Experimental, Numerical and Parametric Study on Ambient Temperature, Fabric Insulation and Metabolic Heat

Abstract

Prior knowledge of the survival time of a person clothed with an extreme cold-weather clothing would be useful in designing an appropriate fabric ensemble. The survival time may depend on ambient temperature, fabric insulation and metabolic heat and can be evaluated by designing a suitable experiment. To study the effect of different parameters on the survival time of humans, one such experiment is designed in an in-house developed guarded hot plate instrument placed inside a cold chamber capable of maintaining the ambient temperature between 210 K to 310 K. The experiments were performed at three different sub-zero temperatures, three different fabric insulation and selecting three metabolic heats. The transient temperature profiles at different locations of the fabric assembly were measured continuously. Further, a one-dimensional heat transfer model was developed to carry out the numerical simulation. The experimental and numerical transient temperature profiles across the fabric assembly agree well. The correlations developed for theoretically predicted survival times compare well with actual experimental data. The parametric analysis has shown that the ambient temperature is the most influencing parameter affecting the survival time followed by fabric insulation. The metabolic heat does not have a significant effect on survival time.