Clothing surface temperature

Clothing surface temperature I he actual mean surface temperature of clothing. 

Composite-Based Laminates. Grade CEM-1 are laminates with continuous-filament glass cloth surfaces and a cellulose core, all with a flame-resistant epoxy resin binder. With good punching practice, sheets up to and including 2.4 mm (0.094 in.) in thickness may be punched at temperatures not less than 23°C (73°F). These laminates meet UL94 V-0 when tested in accordance with UL94. 

Another area of research that could be profitably explored is the use of remote sensing instruments to measure surface temperatures of textile assemblies. Infrared thermovision cameras have been used to visualize temperature distributions over clothed and nude persons in order to study the transport of microorganisms by convective heat flow (112). A variety of less expensive radiometers and radiation pyrometers that are used to measure and automatically control the temperature of textiles during drying and texturing (113, llU, 115) could also assess the thermal behavior of apparel and clothing assemblies and thus elucidate their contribution to thermal comfort indoors. 

Discussion The heat transfer, would be much higher if the person were not dressed since the exposed surface temperature would be higher. Thus, an im-. portant function o( the clothes is to serve as a barrier against heat transfer. 

A = 0-159 W/m C) that covers half of the body while the second one is wearing clothes made of i-mm-tliick synthetic fabric (A = 0.13 W/m °C) that covers the body completely. The ambient air is at 30°C, the heat transfer coefficient at the outer surface is 15 W/m °C, and the inner surface temperature of the clothes can be taken to be 32 C. Treating the body of each person as a 25-cm-diameler, 1.7-m-long cylinder, determine the fractions of heat lost from each person by perspiration. 

It is well established that a clothed or unclothed person feels comfortable v/hen the skin temperature is about 33°C. Consider an average man wearing summer clothes whose thermal resistance is 0.6 cto. The man feels very comfortable while standing in a room maintained at 22 C. The air motion in the room is negligible, and the interior surface temperature of the room is about the same as the air temperature. If this man were to stand in that room unclothed, determine the temperature at which the room must be maintained for him to feel thermally comfortable. 

These squares of mortar with the glass cloth over each, are allowed to "cure" undisturbed for no less than seven days at a surface temperature of 70°F (14 days if the surface is at 60°F-the minimum cure temperature permissible). At the end of that period, the 2" wide open strips between the squares are mortared and cloth covered in the same manner, lapping the cloth 2" over the previously placed squares. (For this part of the work, 6" wide strips of glass cloth are used, and the mortar is extended from the 2" wide bare strip, 2" over the tapered edges of the squares.)... 

Perry and Green (P3, p. 10-14) give a convenient table of natural convection plus radiation coefficients (h + h ) from single horizontal oxidized steel pipes as a function of the outside diameter and temperature difference. The coefficients for insulated pipes are about the same as those for a bare pipe (except that lower surface temperatures are involved for the insulated pipes), since the emissivity of cloth insulation wrapping is about that of oxidized steel, approximately 0.8. A more detailed discussion of radiation will be given in Section 4.11. 

A clothed person with a surface temperature of 28°C is standing in a room of20°C. The surface area is about 1.5 m and the emissivity 0.9. Based on Eq. (3.2.34) we find ... 

Eigure 3 shows the winter and summer comfort zones plotted on the coordinates of the ASHRAE psychrometric chart. These zones should provide acceptable conditions for room occupants wearing typical indoor clothing who are at or near sedentary activity. Eigure 3 appHes generally to altitudes from sea level to 2150 m and to the common case for indoor thermal environments where the temperature of the surfaces (/) approximately equals air temperature (/ and the air velocity is less than 0.25 m/s. A wide range of environmental appHcations is covered by ASHRAE Comfort Standard 55 (5). Offices, homes, schools, shops, theaters, and many other appHcations are covered by this specification. 

Figures 4-65, 4-66, and 4-67 show several units of the bag. The bags may be of cotton, wool, synthetic fiber, and glass or asbestos with temperature limits on such use as 180°F, 200°F, 275°F, 650°F respectively, except for unusual rnaterials. (See Table 4-12A and B.) These units are used exclusively on dry solid particles in a gas stream, not being suitable for wet or moist applications. The gases pass through the woven filter cloth, depositing the dust on the surface. At intervals the unit is subject to a de-dust-ing action such as mechanical scraping, shaking or back-flow of clean air or gas to remove the dust from the cloth. The dust settles to the lower section of the unit and is removed. The separation efficiency may be 99%-i-, but is dependent upon the system and nature of the particles. For extremely fine particles a precoat of dry dust similar to that used in some wet filtrations may be required before re-establishing the pi ocess gas-dust flow.

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