Analysis Of Protective Effects Of PCM Distribution On PCM Thermal Controlling Performance

The effect of heat protection is always the key point in the study of high temperature protective garment.This paper evaluates the PCM waistcoat’s performance of heat protection,air permeability and moisture-penetrability in an imitative high temperature environment.The influence laws of PCM distribution gap,phase-transition temperature and environment temperature on heat protection and thermal-wet comfort of PCM protective garment were discussed in this research.There is a comprehensive comparative analysis to reach the best option.and subjective experiments were conducted to provide a reference for the application of protective garments.(1)This section tested the upward temperature trends in 3 different PCM(20℃,28℃,34℃) and distribution.7 protective waistcoats with different PCM distribution gap were chosen to get the maximum gap that has effective thermal protection.We can get the valid protection time according to the interval layer temperature changes, and get the extreme value of effective protective gap distribution through a linear fitting between interval distribution and protective time.Then comparing the temperature change of the gap and PCM to find out the influence.In the end,analyzing the distribution of PCM gap,environment temperature and the influence of phase change temperature on thermal protection effect via comparing the different combination conditions of protective time.(2)The influence laws of PCM distribution gap on air permeability and moisture-penetrability performance were discussed in this paper.And explore the value range of PCM distribution gap has significant effects on air permeability.(3)Conducted the permeability test of PCM under different distribution gap by using the automatic air permeability instrument, got the fitting clearance and the law of permeability rate equations, then concluded the interval value range which the ventilation rate increased significantly.In a similar way,got the value range of the moisture transmission greatly increase by using the fabric moisture permeability tester.(4)In the end,take the best combination of real experiments for validation based on thepreceding results,and get subjective evaluation of PCM thermal controlling waistcoat.