Modified Rheological Model for Analysis of Compression of Nonwoven Fabrics

Abstract

A new rheological model is presented that describes the compressional behavior of non woven fabrics. In this model, a nonwoven is considered an elastic/viscoplastic material called a Bingham material. To reflect the plastic deformation, the Saint-Venant element of the specific characteristic is introduced. This element reflects the dissipation of energy due to the friction, which depends on the level of reconstruction of the structure of the nonwoven material under compression. The model is verified experimentally with nineteen different nonwovens. A comparative analysis of the compression curves determined theoretically and experimen tally indicates a high level of correlation between both data sets.

Effective thermal conductivity and thermal contact resistance of gas diffusion layers in proton exchange membrane fuel cells. Part 2: Hysteresis effect under cyclic compressive load

“…When the cyclic compression is repeated, the hysteresis effect becomes smaller, and the deformation reaches a steady-state. The variation in hysteresis may be a result of the viscoelastic behavior of the GDL fibers [16][17][18][19][20]. The difference between the unloaded and fresh samples is 4.5% for the first cycle.…”

“…Also, it does not explain the non-recoverable strain during compression and the mechanical hysteresis during compression-release cycling. Recent studies [15][16][17][18][19][20] have focused on accounting for the fiber slippage and the hysteresis observed during compression-release cycling. The cycling induces energy dissipation as a result of viscous damping or frictional losses.…”

“…The cycling induces energy dissipation as a result of viscous damping or frictional losses. An approach taken to model the hysteresis behavior of fibrous media is to consider the structure as a combination of series and parallel springs, dashpots, and Coulomb frictional element [15,16]. Dunlop [15] used such a model to perform simulation that yield a hysteresis loop with a shape similar to the experimental data, but no model verification was performed.…”

Static lateral compression of hemp/filament hybrid yarn knitted fabrics

“…However, textile scientists have been working for over the 50 years on modeling the compression and recovery behavior of fibrous assembly [3,[14][15][16][17][18][19]. Many of these researches have been aimed at improving the model proposed by van Wyk [20].…”

Predicting the behavior of nonwoven geotextile materials made of polyester and polypropylene fibers

“…Anisotropic structure of needled nonwoven materials 10 contributes to various, sometimes hardly explicable, behaviors of nonwoven textiles during stretching. 11 The properties of geotextile materials could be predicted using empiric models, 1 finite model theory and composite material theory, 12 using computer prediction models of nonwoven textile stretching 13 and also using mechanical models, 14–16 whereby the geotextile behavior is described by differential equations. In this way, every type of real material deformation is simulated with a simple model or this simulation is presented by complex models formed by a combination of simple models.…”