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The purpose of this paper is to investigate thermal comfort performances of socks produced from cotton and regenerated cellulosic fiber yarns by thermal resistance (by a newly designed foot thermal manikin), moisture management tester (MMT) parameters and permeability (air and water vapor) tests.

Single jersey fabrics and socks were knitted from 30 Ne yarns produced from cotton, different regenerated cellulosic fibers (viscose, modal, bamboo, micromodal, Tencel®, Tencel LF®) and their blends. Thermal resistances of the socks were compared by a newly developed thermal foot manikin in a more realistic way than measurements in fabric form. Besides air and water vapor permeability, moisture management parameters of the fabrics were tested to differentiate performances of cellulosic fibers.

Results show that air permeability, liquid absorption and transfer parameters measured by MMT are generally identical and better for regenerated cellulosic fabrics than cotton. Micromodal and Tencel® have better performances for liquid transfer and overall moisture management capacities are superior for bamboo and Tencel LF®. Thermal resistances of the socks are minimum for Tencel LF® having a cross-linked structure and maximum for viscose socks.

It is thought that thermal resistance measured in socks form is more realistic than fabric measurements and results of this study that can be valid for all knitted garments. Moreover, comprehensive material plan of the study is valuable for getting reliable results for regenerated cellulosic fibers that have small differences in cases of thermal resistance and liquid transfer.

The purpose of this paper is to provide footwear designers, manikin builders and thermo‐physiological modellers with sweat distribution information for the human foot.

Independent research from two laboratories, using different techniques, is brought together to describe sweat production of the foot. In total, 32 individuals were studied. One laboratory used running at two intensities in males and females, and measured sweat with absorbents placed inside the shoe. The other used ventilated sweat capsules on a passive, nude foot, with sweating evaluated during passive heating and incremental exercise to fatigue.

Results from both laboratories are in agreement. Males secreted more than twice the volume of sweat produced by the females (p<0.01) at the same relative work rate. Both genders demonstrated a non‐uniform sweat distribution, though this was less variable in females. Highest local sweat rates were observed from the medial ankles (p<0.01). The dorsal foot sweated substantially more than the plantar (sole) areas (p<0.01). Sweating on the plantar side of the foot was uniform. Wearing shoes limited the increase in sweat production with increasing load, while the sweat rate of uncovered feet kept increasing with work and thermal load.

The observed variation in sweat rate across the foot shows that footwear design should follow the body mapping principle. Fabrics and materials with different properties can be used to improve comfort if applied to different foot surfaces. The data also demonstrate that foot models, whether physical (manikins) or mathematical, need to incorporate the observed variation across the foot to provide realistic simulation/testing of footwear.

The purpose of this paper is to examine differences between thermal insulation calculated by a global and a serial method using a thermal manikin, in comparison with human trials.

A total of 150 single garments and 38 clothing ensembles were assessed using the manikin; 26 seasonal clothing ensembles were selected for human trials.

The results showed that total insulation of single garments was 16 percent higher in the serial method than in the global method. The difference was higher in garments with smaller covering area per unit garment mass (e.g. winter garments). For seasonal clothing ensembles, the serial values were 39.2 percent (0.18 clo) for spring/fall wear, 62.6 percent (0.15 clo) for summer wear and for winter wear 64.8 percent (0.69 clo) greater than the global values. The clothing insulation by the global method was systemically lower in all 26 seasonal ensembles than values by human trials, which suggests that the values by the global calculation can be more accurately corrected with human testing data.

The paper shows that values by the serial calculation were lower in spring/fall and summer ensembles but greater in winter garments than values collated by human trials. It suggests that the serial values had a lower validity when compared with thermal insulation values collated from human trials.

The paper aims to investigate thermal comfort properties, such as heat and moisture transmission through male business clothing systems, by using a sweating thermal manikin Coppelius that simulates heat and moisture production in a similar way to the human body and measures the influence of clothing on heat exchange in different environmental and sweating conditions.

Ten different combination of male business clothing systems were measured using the sweating manikin, under three environmental conditions (10°C/50 per cent RH, 25°C/50 per cent RH and −5°C), and at 0 and 50 gm⁻² h⁻¹ sweating levels, in order to evaluate the influence of environmental and sweating conditions on thermal comfort properties of clothing systems.

The results show how business clothing systems influence on the dry and evaporative heat loss between the manikin surface and environment in different environmental and sweating conditions.

When using sweating thermal manikin Coppelius, water vapour transmission (WVT) through and water condensation on the clothing can be determined simultaneously with the thermal insulation (I_t) of clothing system. Measured thermal comfort properties of clothing systems evaluated with a sweating thermal manikin can provide valuable information for the clothing industry by manufacturing/designing new clothing systems.

In this investigation, the heat and moisture transmission properties of male business clothing systems were measured in different environmental and sweating conditions. In the past few years, clothing materials containing microencapsulated phase‐change materials (PCMs) have appeared in outdoor garments, particularly sportswear; therefore, we decided to investigate the thermal comfort properties of different standard male business apparel, as well as male business clothing that contain PCMs used as liner and outerwear material.

The purpose of this paper is to study the combined effects of moisture and radiation on thermal protective performance of protective clothing exposed to low level radiation.

Using a sweating manikin, the effect of radiation and moisture on heat and moisture transfer was initially analyzed under the dry manikin with sweating rate of 100 g/(m2h) exposed to 2.5 kW/m2, and then studied at 200 and 300 g/(m2h) exposed to 2 and 3 kW/m2, respectively. Finally, the combined effects of thermal radiation and moisture were predicted by fitting the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity.

The results show that the heat loss and the wet skin surface temperature are affected by the combined effects of moisture and radiation, with two distinctly different trends. Heat loss from the manikin is increasing with the sweating rate, and decreasing with thermal radiation intensity. However, the wet skin surface temperature has an opposite situation.

Two filling equations are given to present the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity. With these two equations, the heat loss and the wet skin surface temperature when exposed to radiation can be predicted by only measuring the mean radiant and ambient temperatures and controlling the sweating rate.

The purpose of this paper is to develop artificial neural networks (ANNs) allowing us to simulate the local thermal insulation of clothing protecting against cold on a basis of the characteristics of materials and design solutions used.

For this purpose, laboratory tests of thermal insulation of clothing protecting against cold as well as thermal resistance of textile systems used in the clothing were performed. These tests were conducted with a use of thermal manikin and so-called skin model, respectively. On a basis of results gathered, 12 ANNs were developed that correspond to each thermal manikin’s segment besides hands and feet which are not covered by protective clothing.

In order to obtain high level of simulations, optimization measures for the developed ANNs were introduced. Finally, conducted validation indicated a very high correlation (above 0.95) between theoretical and experimental results, as well as a low error of the simulations (max 8 percent).

The literature reports addressing the problem of modeling thermal insulation of clothing focus mainly on the impact of the degree of fit and the velocity of air movement on thermal insulation properties, whereas reports dedicated to modeling the impact of the construction of clothing protecting against cold as well as of diverse material systems used within one design of clothing on its thermal insulation are scarce.

The purpose of this study is to determine the effect of ventilation openings and fire intensity on heat transfer and fluid flow within the microclimate between 3D human body and clothing.

On account of interaction effects of fire and ventilation openings on heat transfer process, a 3D transient computational fluid dynamics model considering the real shape of human body and clothing was developed. The model was validated by comparing heat flux history and distribution with experimental results. Heat transfer modes and fluid flow were investigated under three levels of fire intensity for the microclimate with ventilation openings and closures.

Temperature distribution on skin surface with open microclimate was heavily depended on the heat transfer through ventilation openings. Higher temperature for the clothing with confined microclimate was affected by the position and direction of flames injection. The presence of openings contributed to the greater velocity at forearms, shanks and around neck, which enhanced the convective heat transfer within microclimate. Thermal radiation was the dominant heat transfer mode within the microclimate for garment with closures. On the contrary, convective heat transfer within microclimate for clothing with openings cannot be neglected.

The findings provided fundamental supports for the ease and pattern design of the improved thermal protective systems, so as to realize the optimal thermal insulation of the microclimate on the garment level in the future.

The outcomes broaden the insights of results obtained from the mesoscale models. Different high skin temperature distribution and heat transfer modes caused by thermal environment and clothing structure provide basis for advanced thermal protective clothing design.

The purpose of this study is to determine the temperature ratings of infant bedding.

Mathematical models were developed for predicting temperature ratings of infant bedding for all age groups based on the thermal balance equation. These models were validated by the published physiological data and the baby manikin tests. The air temperature was compared with the predicted temperature rating, and the skin temperature of infant or baby manikin was used to explain the validation results.

The models had higher prediction accuracy, especially for the infant bedding with uniformly distributed thermal insulation. The results showed that an increase of 1 clo in thermal insulation caused a decrease of 4.2–6.0 °C in temperature rating. The slope of the model reduced with the increasing month-age, indicating that an older infant had a lower temperature rating than a younger infant.

Suggestions were given for caregivers that younger infants ought to be covered with more bedding than adults; however, older infants were expected to require less bedding.

The outcomes provided scientific guidelines on the selection of bedding for infants at a particular room temperature to ensure the health and safety of infants.

This study examined the wear comfort and thermal insulation properties of Al₂O₃/graphite particle-imbedded sheath/core and dispersed fabrics via a thermal manikin experiment.

Al₂O₃/graphite sheath/core and dispersed polyethylene terephthalate (PET) yarn (POY 120d/24f) were spun using a pilot melt bi-component conjugated spinning machine, which was texturized as 75d/24f on the belt-type texturing machine. The woven fabric specimens were made using nylon 70d/34f in the warp with three types of weft yarn: Al₂O₃/graphite sheath/core, dispersed and regular PET yarns. Thermal insulation properties were measured and compared in terms of the heat retention rate (I) by KES-F7 apparatus and the maximum surface temperature by light heat emission equipment, as verified by the emissivity of various fabric specimens by far-infrared ray experiment. In addition, this study examined the thermal insulation (Clo value) characteristics of the clothes made of Al₂O₃/graphite sheath/core and dispersed fabrics using a thermal manikin apparatus, which were compared with the properties of regular PET clothing.

The thermal insulation of the dispersed fabric was superior to that of the sheath/core fabric, which was tentatively attributed to the higher emissivity of the dispersed yarn with Al₂O₃/graphite particles distributed over the whole yarn cross-section than that from the core of the sheath/core yarn. This result for the clothing measured using a thermal manikin was consistent with the higher heat retention rate (I) and the maximum surface temperature of the dispersed fabric than that of the sheath/core fabric. In addition, the thermal insulation of the dispersed and sheath/core fabrics was superior to that of the regular PET fabric, which revealed that the Al₂O₃/graphite particles imbedded in the dispersed and sheath/core yarns exerted a greater effect on the heat storage and release characteristics compared to that of the TiO₂ particles in regular PET yarn. The Clo values of the dispersed and sheath/core fabrics under the light-on condition were much higher than those under the light-off condition, and furthermore, the difference of the Clo value between the sheath/core and regular PET fabrics under light-on condition was approximately 1.7 times greater than that under the light-off condition. These results revealed that the far-infrared rays emitted from the Al₂O₃/graphite particles imbedded in the sheath/core and dispersed yarns enhance the heat storage and release characteristics from the fabric under the light-on condition, i.e. under the sunlight.

The previously examined thermal wear comfort properties of the various inorganic particle-imbedded fabrics were measured with the fabric state, not clothing, which could not provide objective data related to the actual wearing performance of clothing.

The aim of this work was to validate the Wilson and Laing theoretical mathematical model for estimating the intrinsic “dry” thermal resistance of upper‐bedding, and compare the two‐dimensional models commonly used to estimate the “dry” thermal resistance of bedding in use, with the actual intrinsic “dry” thermal resistance measured using an infant thermal manikin. The Wilson and Laing model was the only model used adequately to estimate the intrinsic “dry” thermal used resistance of materials arranged over the infant thermal manikin. Estimation of intrinsic “dry” thermal resistance of bedding during use is not adequate using two‐dimensional models. Further investigation into the relationship between thermal resistance, conditions of use, and SIDS using the Wilson and Laing model is recommended.