Jintu Fan

Heat and moisture transfer with sorption and condensation in porous clothing assemblies and numerical simulation

Abstract A dynamic model of heat and moisture transfer with sorption and condensation in porous clothing assemblies is presented in this paper. The model considers for the first time the effect of water content in the porous fibrous batting on the effective thermal conductivity as well as radiative heat transfer, which is a very important mode of heat transfer when there is a great difference in the boundary temperatures. The distributions of temperature, moisture concentration and liquid water content in the porous media for different material parameters and boundary conditions were numerically computed and compared. The presented numerical results showed that the condensation zone expends towards its boundaries with time.

Clothing appearance and fit : science and technology

Perception of body appearance and its relation to clothing Subjective assessment of clothing appearance Subjective assessment of clothing fit Objective evaluation of clothing appearance Objective evaluation of clothing fit Fabric properties related to clothing appearance and fit Garment drape 3D body scanning Human anthropometrics and sizing systems Garment design for individual fit.

Modeling heat and moisture transfer through fibrous insulation with phase change and mobile condensates

Abstract This paper reports on a transient model of coupled heat and moisture transfer through fibrous insulation, which for the first time takes into account of evaporation and mobile condensates. The model successfully explained the experimental observations of Farnworth [Tex. Res. J. 56 (1986) 653], and the numerical results of the model were found to be in good agreement with the experimental results of a drying test. Based on this model, numerical simulation was carried out to better understand the effect of various material and environmental parameters on the heat and moisture transfer. It was found that the initial water content and thickness of the fibrous insulation together with the environmental temperature are the three most important factors influencing the heat flux.

Visual perception of male body attractiveness

Based on 69 scanned Chinese male subjects and 25 Caucasian male subjects, the present study showed that the volume height index (VHI) is the most important visual cue to male body attractiveness of young Chinese viewers among the many body parameters examined in the study. VHI alone can explain ca. 73% of the variance of male body attractiveness ratings. The effect of VHI can be fitted with two half bell–shaped exponential curves with an optimal VHI at 17.6 l m–2 and 18.0 l m–2 for female raters and male raters, respectively. In addition to VHI, other body parameters or ratios can have small, but significant effects on male body attractiveness. Body proportions associated with fitness will enhance male body attractiveness. It was also found that there is an optimal waist–to–hip ratio (WHR) at 0.8 and deviations from this optimal WHR reduce male body attractiveness.

Effect of Garment Fit on Thermal Insulation and Evaporative Resistance

This paper reports on an experimental investigation of the effects of garment fit on clothing thermal insulation and moisture vapor resistance, both of which increase with the thickness of the air gap between the garment and the body when the air gap is small. The rate of increase gradually decreases as the air gap becomes thicker, and is much less than the theoretically ideal still air due to natural and forced convection. When the air gap exceeds a certain value, thermal insulation and vapor resistance may decrease with increases in the air gap. Thermal insulation and moisture vapor resistance reach a maximum at a certain air gap thickness depending on fabric properties, wind conditions, and garment fit. Tighter fitting garments are preferable to keep the body warm in windy conditions.

Predicting Garment Drape with a Fuzzy-Neural Network

This paper proposes to use a fuzzy-neural network system to predict and display the drape image of garments made of different fabrics and styles. The new approach is used to develop a prototype drape prediction system to predict the drape of a ladys dress style made from different fabrics. The advantages and disadvantages of the new approach, compared with conventional ones, are discussed.

Fractal analysis of effective thermal conductivity for three-phase (unsaturated) porous media

A fractal analysis of effective thermal conductivity for unsaturated fractal porous media is presented based on the thermal-electrical analogy and statistical self-similarity of porous media. Here, we derive a dimensionless expression of effective thermal conductivity without any empirical constant. The effects of the parameters of fractal porous media on the dimensionless effective thermal conductivity are discussed. From this study, it is shown that, when the thermal conductivity of solid phase and wet phase are greater than that of the gas phase (viz., ks∕kg>1, kw∕kg>1), the dimensionless effective thermal conductivity of unsaturated fractal porous media decreases with decreasing degree of saturation (Sw) and increasing fractal dimension for pore area (Df), fractal dimension for tortuosity (Dt), and porosity (ϕ); when the thermal conductivities of solid phase and wet phase are lower than that of the gas phase (viz., ks∕kg<1, kw∕kg<1), the trends were just opposite. Our model was validated by comparing ...

Engineering apparel fabrics and garments

Handle and making-up performance of fabrics and garments Wrinkling of fabrics and garments Pilling of fabrics and garments Bagging of fabrics and garments Fabric and garment drape Appearance issues in garment processing Durability of fabrics and garments Physiological comfort of fabrics and garments Psychological comfort of fabrics and garments Flammability of fabrics and garments Waterproofing and breathability of fabrics and garments Ultraviolet protection of fabrics and garments Laundry performance of fabrics and garments Application of artificial intelligence in fabric and garment engineering.

Optimal Design of Porous Structures for the Fastest Liquid Absorption

Porous materials engineered for rapid liquid absorption are useful in many applications, including oil recovery, spacecraft life-support systems, moisture management fabrics, medical wound dressings, and microfluidic devices. Dynamic absorption in capillary tubes and porous media is driven by the capillary pressure, which is inversely proportional to the pore size. On the other hand, the permeability of porous materials scales with the square of the pore size. The dynamic competition between these two superimposed mechanisms for liquid absorption through a heterogeneous porous structure may lead to an overall minimum absorption time. In this work, we explore liquid absorption in two different heterogeneous porous structures [three-dimensional (3D) circular tubes and porous layers], which are composed of two sections with variations in radius/porosity and height. The absorption time to fill the voids of porous constructs is expressed as a function of radius/porosity and height of local sections, and the absorption process does not follow the classic Washburns law. Under given height and void volume, these two-section structures with a negative gradient of radius/porosity against the absorption direction are shown to have faster absorption rates than control samples with uniform radius/porosity. In particular, optimal structural parameters, including radius/porosity and height, are found that account for the minimum absorption time. The liquid absorption in the optimized porous structure is up to 38% faster than in a control sample. The results obtained can be used a priori for the design of porous structures with excellent liquid management property in various fields.

Effect of clothing pressure on the tightness sensation of girdles

Girdles should be designed to beautify the lower body part of a woman without creating any discomfort and detrimental physiological effects. This paper reports on an experimental investigation into the relationship between the subjective tightness sensation and the clothing pressure of girdles. The subjective tightness sensation is a measure of the effectiveness of girdles, since too loose means the girdle is not effective in shaping the body and too tight means it is not comfortable and may have detrimental physiological effects. Based on this experimental investigation, the effect of clothing pressure on the tightness sensation is better understood and the optimum pressure distribution of girdles, which is an important criterion for product development and evaluation of girdles, is proposed.