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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 paper is to investigate the effect of air and vapor permeability of jacket materials on ventilation, heat and moisture transfer.

Clothing ventilation (V), thermal insulation (I) and vapor resistance (R _e ) of three jackets made of different materials (normal textile, PVC and “breathable” membrane coated textile), worn on an articulated thermal manikin in a controlled climate chamber, were measured under various conditions, respectively. The various conditions of microenvironment ventilation were created by making the manikin stand and walk, combined with three wind speeds of <0.2, 0.4 and 2.0 m/s, respectively.

In the condition without any forced convection, the air permeability makes no big difference to dry and evaporative heat transfer among the jackets, while the vapor permeability plays a big role in the evaporative heat loss. In the condition with forced convection, the dry heat diffusion is strongly coupled to the evaporative heat transfer in air and vapor permeable textile material.

The effects of ventilation on heat and moisture transfer varies because of different ways of ventilation arising: penetration through the fabric is proven to be the most effective way in vapor transfer although it does not seem as helpful for dry heat diffusion.

The achievements in this paper deepens the understanding of the process of the dry and evaporative heat transfer through clothing, provides clothing designer guidance to choose proper materials for a garment, especially work clothing.

This study aims to investigate the heat transfer mechanism of the uniforms used by people working in hot, humid and windy environments. Furthermore, the effectiveness of an opening structure added to the armpit of the uniforms in improving thermal comfort was comparatively examined.

A set of uniforms was tested with the opening at the armpit alternatively zipped or unzipped. Thermal manikin and human tests were performed in a climatic chamber simulating the specific environmental conditions, including wind speeds at four levels (0.15, 0.5, 2, 4 m/s) and relative humidities at two levels (50 and 85%). Static and dynamic thermal insulations of clothing (I_T) were examined by the thermal manikin tests. The human bodies' thermal responses, including heart rates (HR), eardrum temperatures (T_e), skin temperatures (T_sk) and subjective perceptions, were given by the human tests.

Special mechanisms of heat transfer in the specific uniforms used in tropical monsoon climates were revealed. Reductions on I_T were caused by the movement of the human body and the environmental wind, and the empirical equations would underestimate this reduction. The opening at the armpit was able to prompt more heat transfer under dynamic condition, with reducing the I_T by 11.8%, lowering the mean T_sk by 0.92°C, and significantly improving the subjective perceptions (p < 0.05). The heat exhaustion was alleviated with lowering the T_e by 0.32°C.

This study managed to improve the thermal performance of uniforms for workers under unforgiving conditions. The evaluation and design methods introduced by this study provided practical guidance for similar products with strict dress codes and cost control requirements based on the findings from thorough product tests and analysis.

The aim of the present study is to investigate the effect of fabric weave structure on air permeability and its relation with the garment ventilation.

For this purpose, five groups of cotton/polyester shirting fabrics with plain, T2/1, T2/2, T3/1 and T3/3 weave structures were studied. In order to evaluate ventilation, the garment samples were prepared in different sizes, so that the thickness of the air gap formed between the garment and the body simulator varies by zero, 1.5, 1.2 and 2.9 cm. The effect of wind and its speed (1, 2 and 3 m/s) on clothing ventilation has also been evaluated.

The results indicated that the rise of wind speed and air gap thickness, due to the increased convective heat transfer, would diminish the air gap temperature of clothing and improves its ventilation. In addition, the fabric weave pattern influences the air ability to pass through the fabric, thus affecting the ventilation capability of the garment.

Garments made of fabrics with higher structural firmness, such as the plain, not only have lower air permeability, but also has weaker ventilation capability.

Maintaining air circulation between the wearer and garment layer is crucial for activating heat and moisture transfer from the body. If an air gap is trapped, air circulation may become ineffective and the ventilation of the garment is, thus, hindered. To maintain and extend the air gap, this study aims to propose a design method that involves placing spacer blocks underneath the garment to prevent the fabric from clinging directly to the skin.

To study the application of this design method, a series of T-shirts were produced and tested using a thermal manikin in standing and walking postures. All the T-shirts were made of fabric ostensibly manufactured to have high air permeability. Porous mesh fabric was used to construct the vented panels on the T-shirts. The test was conducted in a chamber with controlled temperature, relative humidity and wind velocity. Total thermal insulation (R_t) and moisture vapour resistance (R_et) were measured.

The test results showed that extension of the air gap between wearer and fabric provided higher ventilation to the wearer if the vented panels were also present on the T-shirts. Different placements of the vented panels on the T-shirts also affected the heat and moisture transfer from the thermal manikin.

Due to limited resources, the evaluation of total thermal insulation and moisture vapour resistance was based on the testing result from a thermal manikin instead of any subjective wearer trial.

This research can contribute to the clothing designer who is developing function wear for a better ventilation.

This research can contribute to the clothing designer who is developing function wear for a better ventilation.

This study aimed to further develop a new design concept in T-shirt design by improving the construction of the spacer blocks. Fabric with higher air and water vapour permeability was used to determine to what extent this design method is applicable to higher performance on heat and moisture transfer.

In previous studies, enlarging the air gap between fabric and the skin through the placement of spacer blocks has been proven to improve air ventilation, particularly when the pumping effect is activated during movement. These studies evaluated only the total thermal insulation (R_t) and moisture vapour resistance (R_et) by using a fabric thermal manikin. The purpose of this paper is to report the experience, perceived comfort level, and ventilation effect of two designed T-shirts in a wearer trial.

An athletic T-shirt (Vented Design) was designed by attaching spacer blocks to the underside of the fabric to enlarge the air gap. Eight subjects participated in the wearer trial, which comprised 30 min treadmill running, followed by 10 min of rest. At different points during the 40 min test period, subjects rated their body coolness, skin dryness, and overall comfort of the designed T-shirt. The testing was repeated with participants wearing the same T-shirt but without spacer blocks, which served as a control garment. The mean skin temperature of each subject was also measured to support survey findings.

The data were evaluated using independent t-tests. The T-shirt with spacer blocks provided higher ventilation than the control T-shirt after 10 min of running. Research limitations – because of limited resources, only eight subjects were recruited to this study. In addition, more T-shirt designs should be tested in the future to elucidate how T-shirt design affects ventilation performance.

This study investigated a T-shirt design wherein the air gap between the skin surface and fabric was increased. The results of the wearer trial showed that this design could be adopted as a design brief for further design development of related clothing. This study has implications for clothing designers developing functional clothing with improved ventilation.

The purpose of this paper is to explore the effects of wind direction and ease allowance on thermal comfort in sportswear.

The effects of wind direction (front, side, back and calm (no wind) 1.5 m/s) and seven magnitudes of ease allowance on sportswear thermal insulation and surface temperature were investigated. An 11 zones’ thermal manikin was used to acquire the static thermal insulation. Surface temperature was captured by a thermal imager.

The results showed that the wind was a significant effect on thermal performance, however, wind direction effect was only significant in the segment covered with multilayer fabric, such as the abdomen and hip (p=0.034). Although the ease allowance influenced the overall thermal insulation obviously, the difference between seven sizes suits was not significant. Nevertheless, the ease allowance affected the surface temperature of chest and back significantly (p=0.023, 0.007). Correlation between thermal insulation and surface temperature was negative, and correlation level was degraded when affected by wind factor.

Sportswear’s fabric and style did not discussed as effect factors. It would be taken into accounted in the future research.

Wind direction impact thermal comfort in multilayer regions significantly. It is a reference to improve sportswear’s comfort design.

The purpose of this paper is to determine the effect of flash fire exposure on the mechanical properties of single-layer thermal protective clothing.

The full-scale flame manikin tests were performed to simulate flash fire exposure. Two typical fire-resistant fabrics were investigated. The manikin was divided into seven body parts and the specimens meeting the requirements of tensile and tear strength standards were sampled. Fabric thickness, mass per unit area, tensile strength and tear strength were measured and analyzed.

The results revealed the significant influence of heat flux on both of tensile and tear strength. However, the regression analysis indicated the low R² of the liner models. When the tensile and tear strength retention were reorganized based on the body parts, both of the multiple linear regression models for tensile and tear strength showed higher R² than the one-variable linear regressions. Furthermore, the R² of the multiple linear regression model for tear strength retention was remarkably higher than that of the tensile strength.

The findings suggested that greater attention should be paid to the local part of human body and more factors such as the air gap should be considered in the future thermal aging of firefighters’ clothing studies.

The outcomes provided useful information to evaluate the mechanical properties of thermal protective clothing and predict its service life.

Clothing fit, including garment ease and drape, impacts the volume of air between clothing layers and the body, directly affecting the amount of heat that can be transferred through a multi-layer clothing system. As most acute firefighting fatalities are caused by overexertion and heat strain, the purpose of this research was to determine the impact of ease allowances on air gaps in structural firefighting turnout suits and their subsequent effect on total heat loss (THL) when worn on a three-dimensional form.

Four turnout suits with chest ease allowances of 6″, 8″, 10″ and 12″ were evaluated using an ANDI dynamic sweating thermal manikin. The average predicted manikin THL of each ensemble was calculated from the thermal and evaporative resistance measurements. A three-dimensional (3D) body scanner was utilized to calculate the distance and volume of clothing air gaps between the base layer and each turnout suit.

Results demonstrate that reductions in upper body ease measurements trend towards statistically significant increases in THL, to a point, with fit limitations being reached before benefits can be significantly realized. An increase in standard chest ease measurements significantly decreased heat loss, even when forced convection from movement was considered.

This is the first article of its kind to explore the relationship between garment ease and predicted manikin THL, especially for fire service protective clothing. Findings indicate a valid recommendation for turnout gear designers and manufacturers to optimize clothing fit to improve breathability and potentially reduce incidents of heat strain in the fire service.

The purpose of this paper is to investigate the influence and relationship of segment area and opening area in segmented protective pad in comparison to non-segmented pad to the energy absorption and performance attributes relevant to thermophysiological wear comfort.

The compressive stress-strain curves were obtained using Instron Tester and were used to analyse the energy absorption of the pads and the segmented pad assemblies. The dry thermal resistance and evaporative resistance of the non-segmented and segmented protective pads were obtained using MTNW Sweating Guarded Hot Plate.

The compression test results and performance attributes relevant to thermophysiological wear comfort test result demonstrated that the area segment and opening area of segmented pad influenced their energy absorption value, dry thermal resistance value and evaporative resistance value (permeability index value).

The results are expected to be useful for design and engineering of hip impact protective garments. Hip impact protective pads are used to prevent hip fractures in elderly people as a result of fall.