Contents
Contributor contact details xi
Introduction xiv
Part I Textile structure and moisture transport
1 Characterizing the structure and geometry of fibrous materials 3
N. PAN and Z. SUN, University of California, USA
1.1 Geometrical characterization of single fibers 3
1.2 Basic parameters for porous media 4
1.3 Characterization of fibrous materials 6
1.4 Mathematical descriptions of the anisotropy of a fibrous material 11
1.5 Pore distribution in a fibrous material 14
1.6 Tortuosity distributions in a fibrous material 17
1.7 Structural analysis of fibrous materials with special fiber orientations 19
1.8 Determination of the fiber orientation 33
1.9 The packing problem 37
1.10 References 38
2 Understanding the three-dimensional structure of fibrous materials using stereology 42
D. LUKAS and J. CHALOUPEK, Technical University of Liberec,
Czech Republic
2.1 Introduction 42
2.2 Basic stereological principles 54
2.3 Stereology of a two-dimensional fibrous mass 64
2.4 Stereology of a three-dimensional fibrous mass 82
2.5 Sources of further information and advice 98
2.6 References 98
3 Essentials of psychrometry and capillary hydrostatics 102
N. PAN and Z. SUN, University of California, USA
3.1 Introduction 102
3.2 Essentials of psychrometry 103
3.3 Moisture in a medium and the moisture sorption isotherm 106
3.4 Wettability of different material types 115
3.5 Mathematical description of moisture sorption isotherms 119
3.6 References 132
4 Surface tension, wetting and wicking 136
W. ZHONG, University of Manitoba, Canada
4.1 Introduction 136
4.2 Wetting and wicking 136
4.3 Adhesive forces and interactions across interfaces 138
4.4 Surface tension, curvature, roughness and their effects on wetting phenomena 143
4.5 Summary 152
4.6 References 153
5 Wetting phenomena in fibrous materials 156
R. S. RENGASAMY, Indian Institute of Technology, India
5.1 Introduction 156
5.2 Surface tension 156
5.3 Curvature effect of surfaces 158
5.4 Capillarity 160
5.5 Surface roughness of solids 167
5.6 Hysteresis effects 176
5.7 Meniscus 178
5.8 Instability of liquid flow 180
5.9 Morphological transitions of liquid bodies in parallel fiber bundles 183
5.10 Sources of further information and advice 184
5.11 References 184
6 Interactions between liquid and fibrous materials 188
N. PAN and Z. SUN, University of California, USA
6.1 Introduction 188
6.2 Fundamentals 188
6.3 Complete wetting of curved surfaces 193
6.4 Liquid spreading dynamics on a solid surface 195
6.5 Rayleigh instability 199
6.6 Lucas–Washburn theory and wetting of fibrous media 203
6.7 Understanding wetting and liquid spreading 214
6.8 References 219
Part II Heat–moisture interactions in textile materials
7 Thermal conduction and moisture diffusion in fibrous materials 225
Z. SUN and N. PAN, University of California, USA
7.1 Introduction 225
7.2 Thermal conduction analysis 226
7.3 Effective thermal conductivity for fibrous materials 233
7.4 Prediction of ETC by thermal resistance networks 237
7.5 Structure of plain weave woven fabric composites and the corresponding unit cell 241
7.6 Prediction of ETC by the volume averaging method 249
7.7 The homogenization method 259
7.8 Moisture diffusion 262
7.9 Sensory contact thermal conduction of porous materials 265
7.10 Future research 266
7.11 References 266
8 Convection and ventilation in fabric layers 271
N. GHADDAR, American University of Beirut, Lebanon;
K. GHALI, Beirut Arab University, Lebanon; and
B. JONES, Kansas State University, USA.
8.1 Introduction 271
8.2 Estimation of ventilation rates 275
8.3 Heat and moisture transport modelling in clothing by ventilation 283
8.4 Heat and moisture transport results of the periodic ventilation model 298
8.5 Extension of model to real limb motion 301
8.6 Nomenclature 302
8.7 References 305
9 Multiphase flow through porous media 308
P. GIBSON, U.S. Army Soldier Systems Center, USA
9.1 Introduction 308
9.2 Mass and energy transport equations 308
9.3 Total thermal energy equation 328
9.4 Thermodynamic relations 336
9.5 Mass transport in the gas phase 338
9.6 Gas phase convective transport 340
9.7 Liquid phase convective transport 341
9.8 Summary of modified transport equations 344
9.9 Comparison with previously derived equations 347
9.10 Conclusions 351
9.11 Nomenclature 352
9.12 References 355
10 The cellular automata lattice gas approach for fluid flows in porous media 357
D. LUKAS and L. OCHERETNA, Technical University of Liberec,
Czech Republic
10.1 Introduction 357
10.2 Discrete molecular dynamics 364
10.3 Typical lattice gas automata 378
10.4 Computer simulation of fluid flows through porous materials 381
10.5 Sources of further information and advice 395
10.6 References 399
11 Phase change in fabrics 402
K. GHALI, Beirut Arab University, Lebanon; N. GHADDAR,
American University of Beirut, Lebanon; and B. JONES,
Kansas State University, USA
11.1 Introduction 402
11.2 Modelling condensation/evaporation in thin clothing layers 407
11.3 Modelling condensation/evaporation in a fibrous medium 411
11.4 Effect of fabric physical properties on the condensation/ evaporation process 416
11.5 Modelling heating and moisture transfer in PCM fabrics 418
11.6 Conclusions 420
11.7 Nomenclature 421
11.8 References 422
12 Heat–moisture interactions and phase change in fibrous material 424
B. JONES, Kansas State University, USA; K. GHALI, Beirut Arab
University, Lebanon; and N. GHADDAR, American University of
Beirut, Lebanon
12.1 Introduction 424
12.2 Moisture regain and equilibrium relationships 426
12.3 Sorption and condensation 427
12.4 Mass and heat transport processes 428
12.5 Modeling of coupled heat and moisture transport 431
12.6 Consequences of interactions between heat and moisture 434
12.7 References 436
Part III Textile–body interactions and modelling issues
13 Heat and moisture transfer in fibrous clothing insulation 439
Y.B. LI and J. FAN, The Hong Kong Polytechnic University,
Hong Kong
13.1 Introduction 439
13.2 Experimental investigations 439
13.3 Theoretical models 448
13.4 Numerical simulation 456
13.5 Conclusions 463
13.6 Nomenclature 465
13.7 References 466
14 Computer simulation of moisture transport in fibrous materials 469
D. LUKAS, E. KOSTAKOVA and A. SARKAR, Technical University of
Liberec, Czech Republic
14.1 Introduction 470
14.2 Auto-models 478
14.3 Computer simulation 509
14.4 Sources of further information and advice 536
14.5 References 538
15 Computational modeling of clothing performance 542
P. GIBSON, U.S. Army Soldier Systems Center, USA; J. BARRY and
R. HILL, Creare Inc, USA; P. BRASSER, TNO Prins Maurits Laboratory,
The Netherlands; and M. SOBERA and C. KLEIJN, Delft University of
Technology, The Netherlands
15.1 Introduction 542
15.2 Material modeling 543
15.3 Material modeling example 545
15.4 Modeling of fabric-covered cylinders 546
15.5 Full-body modeling 554
15.6 Conclusions 558
15.7 References 558
16 The skin’s role in human thermoregulation and comfort 560
E. ARENS and H. ZHANG, University of California, Berkeley, USA
16.1 Introduction 560
16.2 Body–environment exchange 561
16.3 Skin 564
16.4 Heat exchange at the skin surface 578
16.5 Moisture exchange at the skin surface 584
16.6 Typical skin temperatures 585
16.7 Sensation and comfort 589
16.8 Modeling human thermal regulation and comfort 596
16.9 References 597
Index 603