Thermal comfort improvement

Li, Z. H. 1994. Fundamental studies on ventilation for improving thermal comfort and I.AQ. Ph.D. thesis. University of Illinois. 

A workbench makes use of a local air supply in conjunction with exhaust air to ensure good control of the contaminants generated on a bench process. The local exhaust removes the contaminants, while the local supply air protects the operator and/or the products against airborne contaminants. The local supply air improves the thermal environmental conditions by introducing cool dehumidified air in a hot environment. This ensures that the operator s thermal comfort is maintained in areas of high temperature, where full air conditioning of the entire workspace is nor economically feasible. 

A114Rest is a European-funded project focussing on improving tactile and thermal comfort in rest systems to promote a deeper, more restorative sleep. In the project s framework textile sensors embedded in a mattress were developed to monitor sleeping quality by measuring body movement and room temperature. This section summarises the results on the sensor systems (A114Rest, 2011). 

Manufacturers have developed new nonwoven fabrics for surgical gowns that provide improved liquid barrier protection. However, the technology necessary to make a fabric impervious to liquid penetration may also increase the fabric s resistance to evaporative heat transfer. Consequently, there may be a trade-off between adequate liquid barrier protection (i.e., safety) and thermal comfort in the operating room. 

Chen X, Kunz E. Analysis of 3D woven structure as a device for improving thermal comfort of ballistic vests. Int J Cloth Sci Technol 2005 17(3/4) 215—24. 

D honeycomb weave structure for improved thermal comfort... 

Multifunctional Materials. Multifunctional property improvement by binding of specific polymers to fibers and fibrous products has been extensively investigated and reviewed (81). With poly(ethylene glycol) as the bound polymer, functional and aesthetic property improvements include thermal comfort, liquid absorbency/repellancy, increased wear life, soil release, resistance to static charge, antimicrobial activity, and resiliency. Numerous applications such as sportswear/ski wear, protective clothing for health care workers, durable and nondurable hygienic items, work uniforms, and space suits are being commercialized and evaluated. 

Additional materials in the form of coatings, reinforcements, laminates, or plastic film are often added to improve the performance in barrier resistance, absorbency and nonslippage. These approaches improve the protective performance, but whether they take into consideration the thermal comfort of the wearer is questionable (Song, Cao, Cloud, 2011). 

Alagirusamy, 2010). Clothing is considered as a system that interacts with the body and must support thermoregulation of the body by maintaining its thermal balance (constant body core temperature of 37 °C) and providing a comfortable microclimate next to the skin (Li and Wong, 2006). Prevention of heat stress could lead to improved competitive performance for the athlete, whereas unnecessary heat and moisture next to the skin could have adverse effects on both performance and health. 

The wear comfort of a fiber is determined by its softness, thermal isolation properties, water uptake, and permeability properties. The more or less hydrophobic synthetic fibers are consequently hydrophilized to improve wear comfort. The hydrophilization should increase dampness uptake, improve softness, decrease the tendency to soil, and reduce electrostatic charging. In high-grade finishing, the fibers or weaves are treated for this purpose with ethoxylated fatty alcohols, fatty acids, fatty amides, or with quaternary ammonium or sulfonium derivatives. Alternatively, the fibers can be hydrophilized by grafting with, for example, acrylamide or methacrylic acid. 

Another example of a comfortable garment is made from microencapsulated PCMs, packed into a space between two fabric layers in order to produce a garment with passive, regenerative thermal protection. The garment offers improved comfort due to not only enhanced thermal control but also by enabling the transport of humidity through the PCM layer and away from the body. 

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