A theoretical model is demonstrated that provides a reliable prediction of thermal transmission through nonwoven structures. The validity of the model is confirmed in experiments that measure the thermal conductivity of various nonwoven barrier fabrics. The model is used to characterize the relative contribution of heat transfer mechanisms to the total heat transmission. It also provides a good explanation of the roles played by fiber and fabric variables in determining the thermal insulation of nonwoven barrier materials.
Get full access to this article
View all access options for this article.
References
1.
Aronson, J.R. , et al., Infrared Emittance of Fibrous Materials, Appl. Optics18, 2622 (1979 ).
2.
Bacon, G.E., A Method for Determining the Degree of Orientation of Graphite, J. Appl. Chem. 6(11), 477 ( 1956 ).
3.
Bankvall, C.G. , Heat Transfer in Fibrous Materials, J. Test. Eval. 1, 235 (1973).
4.
Baxter, S., Thermal Conductivity, Proc. Phys. Soc. London58, 105 (1946).
5.
Bomberg, M., and Klarsfeld, S., Semi-Empirical Model of Heat Transfer in Dry Mineral Fiber Insulations, J. Therm. Insul. 6(1), 156 (1983).
6.
Davis, L.B., Jr., and Birkebak, R.C., On the Transfer of Energy in layers of Fur, Biophys. J. 14, 249 ( 1974 ).
7.
Dent, R.W., Donovan, J.G., and Skelton, J., Development of Synthetic Down-Alternatives, AlbanyInternational Research Co., Research Report, U.S. Army Contract No. DAAK60-83-C-0022, 1984.
8.
Farnworth, B. , Comments on "Heat Transfer Characteristics of Nonwoven Insulating Materials," Textile Res. J . 57, 615 (1987).
9.
Farnworth, B. , A Numerical Model of Combined Diffusion of Heat and Water Vapor Through Clothing, Textile Res. J . 56, 653 (1986).
10.
Farnworth, B., Mechanisms of Heat Flow Through Clothing Insulation, Textile Res. J., 53(12), 717 (1983).
11.
Hager, N.E. , Jr., and Steere, R.C., Radiant Heat Transfer in Fibrous Thermal Insulation, J. Appl. Phys. 38, 4663 (1967 ).
12.
Kawabata, S. , Measurement of Anisotropic Thermal Conductivity of Single Fiber, J. Textile Machin. Soc. Jpn . 39(12), 184 (1986).
13.
Kelly, B.T., "The Thermal Conductivity of Physics of Carbon," Marcel Dekker, NY, 1969, pp. 119.
14.
Lamb, G.E.R. , Heat and Water Vapor Transport in Fabrics Under Ventilated Conditions, Textile Res. J . 62, 387(1992).
15.
Lamb, G.E.R., and Yoneda, M., Heat Loss from a Ventilated Clothed Body, Textile Res. J. 60, 378 (1990).
16.
Lamb, G.E.R., and Duffy-Morris, K. , Heat Loss Through Fabrics Under Ventilation With and Without a Phase Transition Additive, Textile Res. J. 60, 261 (1990).
17.
Larkin, B.K., and Churchill, S.W., Heat Transfer by Radiation through Porous Insulations, J. Am. Inst. Chem. Eng. 5,467 (1059).
18.
Larson, R.E., Rust, L.W., Jr., Kydd, A.R., and Gauvin, G.A., Investigations of Heat and Mass Water Vapor and Liquid Movement through Clothing System, Natl. Tech. Info. Serv. Rep., AD691144, 1968.
19.
Li, Y., Holcombe, B.V., and Apcar, F., Moisture Buffering Behavior of Hygroscopic Fabric During Wear, Textile Res. J. 62, 619 (1992).
20.
Maxwell, J.C. , "A Treatise on Electricity and Magnetism," Clarendon Press, Oxford, 1904.
21.
Martin, J.R. , and Lamb, G.E.R., Measurement of Thermal Conductivity of Nonwovens Using a Dynamic Method, Textile Res. J. 57, 721 (1987).
22.
Mckay, N.L. , Timusk, T., and Famworth, B., Determination of Optical Properties of Fibrous Thermal Insulation, J. Appl. Phys. 55, 4064 (1984).
23.
Naka, S., and Kamata, Y., Thermal Conductivity of Wet Fabrics, J. Textile Machin. Soc. Jpn. 23(4),114 (1977).
24.
Pelanne, C.M. , Heat Flow Principles in Thermal Insulations , J. Therm. Insul. 1, 48 ( 1977).
25.
Schneider, A.M., Hoschke, B.N., and Goldsmid , H.J., Heat Transfer. Through Moist Fabrics, Textile Res. J. 62, 61 (1992).
26.
Schuhmeister, J., Versuche uber dasWarmeleitungsvermogen der Baumwolle, Schafwolle u Seide, Ber. K. Akad. Wien. Math.-Naturwiss. Klasse 76.283 (1877).
27.
Speil, S., Low Density Thermal Insulations for Aerospace Applications, Appl. Mater. Res. 3, 238 ( 1964).
28.
Strong, H.M. , Bundy, F.P., and Bovenkerk , H.P., Flat Panel Vacuum Thermal Insulation, J. Appl. Phys. 31, 39( 1960).
29.
Stuart, I.M. , and Holcombe, B.V., Heat Transfer through Fiber Beds by Radiation with Shading and Conduction, Textile Res. J. 54, 149 (1984).
30.
Suzuki, A., and Ohira, M., Study on the Model of the Thermal Conductivity of Wet Fabrics, J. Textile Machin. Soc. Jpn. 30(9), T158 (1977).
31.
Tong, T.W., and Tien, C.L., Analytical Models for Thermal Radiation in Fibrous Insulations, J. Therm. Insul. 4, 27 ( 1980).
32.
Van der Held, E.F.M., The Contribution of Radiation to the Conduction of Heat, II. Boundary Conditions, Appl. Sci. Res. Sect. A.4, 77 (1953).
33.
Verschoor, J.D., and Greebler , P., Heat Transfer by Gas Conduction and Radiation in Fibrous Insulations, Am., Soc. Mech. Eng. 74,961 (1952).
34.
Yoon, H.N., and Buckley, A., Improved Comfort Polyester, Part II: Transport Properties and Thermal Comfort of Polyester / Cotton Blend Fabrics, Textile Res. J . 54, 289( 1984).
