Phase-change clothing

A student hangs wet clothes outdoors on a winter day when the temperature is — 15°C. After a few hours, the clothes are found to be fairly dry. Describe the phase changes in this drying process. 

Zhu Fanglong. 2011. Additional heat transfer numerical simulation of phase change material layer thermal protective clothing [J]. Journal of applied basic and engineeringscierwes, ll(04) 79-85. 

Evaporation/condensation heat transfer between the body, the clothing and the environment can also occur through the evaporation of hquid water or the condensation of water vapour. This phase change of water is dependent on the latent heat of vaporisation, which is temperature-dependent. 

Pause BH. New heat protective garments with phase change material. In Nelson CN, Henry NW, editors. Performance of protective clothing issues and priorities for the 21st century, vol. 7. West Conshohocken, PA American Society for Testing and Materials 2000. p. 3-13. ASTM STP 1386. 

The PCMs having the most suitable phase change temperature for clothing are organic compounds such as paraffins or linear alkyl hydrocarbon, non-paraffinic materials (e.g., hydrocarbon alcohol, hydrocarbon acid. 

Another example of phase change technology used in protective clothing utilizes evaporative cooling technology. Cooling fibres introduce water-... 

Shim H, McCullough EA and Jones BW (2001), Using phase change materials in clothing. Textile Research Journal, 71(6), pp. 495-520. 

Colvin, D.P., Bryant, Y.G., 1998. Protective clothing containing encapsulated phase change materials. In Proceedings of the 1998 ASME International Mechanical Engineering Congress and Exposition, November 15—20, 1998, Fairfield, NJ, USA, pp. 123—132. 

Name the phase change in each of these events (a) Dew appears on a lawn in the morning, (b) Icicles change into liquid water, (c) Wet clothes dry on a summer day. 

In contrast to the other plastic crystal substance DMP, the HMP did not volatilize from the fabric when it was dried at conventional or elevated temperature to remove excess water. The modified fabrics had heat contents of 87.78-104.5 J/g on heating and 79.42-96.14 J/g on cooling after one to ten thermal cycles. The heat contents of HMP-treated fabrics were 1.7-2.5 times those of untreated fabrics. The fabrics are not suitable for clothing textiles, due to their high phase change temperature. 

Pause B H, Development of new cold protective clothing with phase change material , Int Con Safety and Protective Fabrics, April 29-May 1, 104,1998. 

Fan, J., Cheng, X.Y., 2005. Heat and moisture transfer with sorption and phase change through clothing assembhes. Part II theoretical modeling, simulation, and comparison with experimental results. Text. Res. J. 75 (3), 187-196. 

McCarthy, L.K., Marzo, M., 2011. The application of phase change material in fire fighter protective clothing. Fire. Technol48 (4), 841-864. 

When the temperature of the skin of the human body differs by more than S O C from its ideal temperature, the person feels uncomfortable (Tao, 2001 Manila, 2006). It would be desirable, if at high temperatures the excess heat produced could be stored in the clothing system and then released when the person starts to get cold. Phase change materials (PCMs) that have been used to regulate temperature fluctuations have this function (Han and Hubbell, 1997 Langer, 1990 Sonet al., 1991 Veronese eta/., 1996). 

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