Sage Journals: Discover world-class research

Abstract

Radiation heat transfer within the fabric used in fire protective clothing is one of the critical factors affecting thermal protective performance under simulated fire. In the present article, a fractal analysis of effective thermal conductivity for flame-resistant fabric is presented based on the thermal-electrical analogy and statistical self-similarity of yarns within fabric. The thermal radiation influence is considered in the fractal model. Structural models of yarn and plain woven fabric are derived based on the fractal characteristics of macropores (gaps or channels) between the yarns and micropores inside the yarns. The fractal effective thermal conductivity model can be expressed as a function of the pore structure (fractal dimension) and architectural parameters of the woven fabric. It was found that the calculated results corresponded well with the experimental data within an average of. 4.9% at mean tested temperature of 200°C. This confirms the good behavior of the model and the validity of results. Thermal conductivity values increased for fabric under high temperature as mean test temperatures are increased due to the nonlinear nature of radiation heat transfer.

Keywords

fire protective clothing fractal woven fabrics thermal conductivity.

Get full access to this article

View all access options for this article.

References

Hirschler, M.M. (1997). Analysis of Thermal Performance of Two Fabrics Intended for Use as Protective Clothing, Fire and Materials, 21: 115-121.

Zhu, F.L. and Zhang, W.Y. (2009). Modeling Heat Transfer for Heat-resistant Fabrics Considering Pyrolysis Effect Under an External Heat Flux, Journal of Fire Sciences, 27(1): 81-96.

Mohammadi, M. and Lee, P.B. (2003). Determining Radiative Heat Transfer Through Heterogeneous Multilayer Nonwoven Materials , Textile Research Journal, 73(10): 896-900.

Goo, N.S. and Woo, K. (2003). Measurement and Prediction of Effective Thermal Conductivity for Woven Fabric Composites , International Journal of Modern Physics B, 8-9: 1808-1813.

Calmidi, V.V. and Mahajan, R.L. (1999). The Effective Thermal Conductivity of High Porosity Fibrous Meta Foams, Journal of Heat Transfer - Transactions of the ASME, 121: 466-471.

Mowrer, F.W. (2005). An Analysis of Effective Thermal Properties of Thermally Thick Materials, Fire Safety Journal, 40: 395-410.

Staggs, J.E.J. (2002). Estimating the Thermal Conductivity of Chars and Porous Residues Using Thermal Resistor Networks , Fire Safety Journal, 37: 107-119.

Zhao, S.Y. , Zhang, B.M. and Du, S.Y. ( 2009). An Inverse Analysis to Determine Conductive and Radiative Properties of a Fibrous Medium, Journal of Quantitative Spectroscopy & Radiative Transfer, 110: 1111-1123.

Yamashita, Y. , Yamada, H. and Miyake, H. (2008). Effective Thermal Conductivity of Plain Weave Fabric and Its Composite Material Made from High Strength Fibers , Journal of Textile Engineering , 4: 111-119.

10.

Yu, B.M. and Lee, L.J. ( 2000). A Simplified In-plane Permeability Model for Textile Fabrics, Polymer Composites , 5: 660-685.

11.

Mandelbrot, B.B. ( 1983). The Fractal Geometry of Nature, Freeman , San Francisco.

12.

Pitchumani, R. and Yao, S.C. (1991). Correlation of Thermal Conductivities of Unidirectional Fibrous Composites Using Local Fractal Techniques , Journal of Heat Transfer - Transactions of the ASME, 113: 788-796.

13.

Yu, B. and Cheng, P. ( 2002). Fractal Models for the Effective Thermal Conductivity of Bidispersed Porous Media, AIAA Journal of Thermophysics and Heat Transfer, 16: 22-29.

14.

Wang, B.X. , Zhou, L.P. and Peng, X.F. ( 2003). A Fractal Model for Predicting the Effective Thermal Conductivity of Liquid with Suspension of Nanoparticles, International Journal of Heat and Mass Transfer, 46: 2665-2672.

15.

Gao, J. and Pan, N. (2009). Explanation of the Fractal Characteristics of Goose Down Configurations, Textile Research Journal, 79: 1142-1147.

16.

Gao, X.S. , Tong, Y. , Zhang , Y. and Hong, J.Q. (2000). The Fractal Structure of Natural Fibers and the Development of Fiber with Fractal Structure, China Synthetic Fiber Industry, 23: 35-38.

17.

Neves, J. , Neves, M. and Janssens, K. ( 1994). Fractal Geometry-A New Tool for Textile Design Development Applications in Printing, International Journal of Clothing Science and Techology, 6(1): 28-36.

18.

Yu, B.M. and Lee, J. (2002). A Fractal In-plane Permeability Model for Fabrics, Polymer Composites , 2: 201-221.

19.

Wheatcraft, S.W. and Tyler, S.W. (1988). An Explanation of Scale-Dependent Dispersivity in Heterogeneous Aquifers Using Concepts of Fractal Geometry , Water Resources Research, 24: 566-578.

20.

Stanley, H.E. (1985). Fractal Concepts for Disordered System: The Interplay of Physics and Geometry, In: Pynn, R. and Skjeltorp, A. (eds.), Scaling Phenomena in Disordered Systems, NATO ASI Series B , Vol. 133, pp. 85-97, Plenum Press, New York.

21.

Cenens, C. and Van, B.K.P. ( 2001). On the Development of A Novel Image Analysis Technique to Distinguish Between Flocs and Filaments in Activated Sludge Images, Water Science Technology, 46(1-2): 381-387.

22.

He, G.L. , Zhao, Z.C. , Ming, P.W. , Abuliti, A. and Yin , C.Y. (2005). A Fractal Model for Predicting Permeability and Liquid Water Relative Permeability in the Gas Diffusion Layer of PEMFCs, Journal of Power Sources , 163: 846-852.

23.

Yu, B.M. and Li, J.H. ( 2001). Some Fractal Characters of Porous Media, Fractals, 9(3): 365-372.

24.

Chen, Y.P. and Shi, M.H. ( 1999). Determination of Effective Thermal Conductivity for Real Porous Media Using Fractal Theory, Journal of Thermal Science , 2: 102-107.

25.

Cao, H.J. , Qian, K. and Li , H.S. (2009). Quantitative Expression of Yarn Cross Section Pore Structure, Journal of TianJin Polytechnic University, 28(3): 37-40.

26.

Viskantan, R. (1965). Heat Transfer by Simultaneous Conduction and Radiation in an Absorbing Medium, Journal of Heat Transfer-Transactions of the ASME, 2: 63-72.

27.

Aduda, B.O. ( 1996). Effective Thermal Conductivity of Loose Particulate System , Journal of Materials Science , 31: 6441-6448.

28.

ASTM C 518. (1998). Standard Test Method for Steady State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus, American Society for Testing and Materials, Philadelphia.

29.

Nield, D.A. (1991). Estimation of the Stagnant Thermal Conductivity of Saturated Porous Media, International Journal of Heat and Mass Transfer, 34: 1575-1576.

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.01 MB

Fractal Analysis of Effective Thermal Conductivity for Woven Fabrics used in Fire Fighters’ Protective Clothing

Abstract

Keywords

Get full access to this article

References

Supplementary Material