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1 – 10 of 952J. Fan and J.H. Keighley
The effects of body motion, clothing design and environmental conditions on the thermal insulation of clothing systems were investigated by using a newly developed fabric manikin…
Abstract
The effects of body motion, clothing design and environmental conditions on the thermal insulation of clothing systems were investigated by using a newly developed fabric manikin. The manikin was covered with four typical clothing systems, and the changes of thermal insulation of these clothing systems and the heat lost from the clothed manikin were examined under various walking speeds (0–1.2 km/hr), wind velocities (0–2.2 m/s), and ambient temperature (—20°C–20°C) inside an environmental chamber. Out of this work, better understanding of the reduction of thermal insulation, owing to the combined effects of body motion and wind, are achieved. Also, the work showed the significant effect of ambient temperature on the effective clothing thermal insulation and the advantage of using aluminium foil in the construction of clothing for use in cold environments. Finally, the work revealed the fact that body motion can have a very significant effect on the clothing thermal insulation even though body activity is low. This explains why people, when they feel cold, like to increase their activity level in order to increase heat production rather than reduce their activity level to reduce the heat lost.
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Radostina A. Angelova, George Pichurov, Iskra Simova, Peter Stankov and Iosu Rodrigo
– The purpose of the paper is to simulate the effect of clothing insulation and activity on the interaction between the human body and the environment.
Abstract
Purpose
The purpose of the paper is to simulate the effect of clothing insulation and activity on the interaction between the human body and the environment.
Design/methodology/approach
A thermo-physiological model, integrated into a Fluent CFD software package is applied. The temperature of the skin surface, clothing surface and heat flux (dry and total heat flux) through layers of clothing with different insulation level are numerically investigated in function of the clothing insulation and the different activities performed indoors.
Findings
The increase of the clothing insulation leads to increase of both skin and clothing temperature. Higher temperature difference ΔT between the room temperature and skin temperature provokes more dynamic change of the skin temperature and decreases the thermal comfort of the person. The increase of the metabolic rate, however, leads to more uniform skin temperature, regardless the temperature difference ΔT. With the increase of the clothing insulation for a constant metabolic rate the total heat flux remains constant, but the dry heat flux decreases, while the evaporative heat flux increases.
Originality/value
The joint influence of clothing insulation and indoor activities on the thermal interaction between the body and the environment is assesses using a thermo-physiological model, integrated in a CFD software package.
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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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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).
Originality/value
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.
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The purpose of this paper is to analyze the impact of design solutions used in clothing on the thermal resistance of the material systems from which the clothing is made, design…
Abstract
Purpose
The purpose of this paper is to analyze the impact of design solutions used in clothing on the thermal resistance of the material systems from which the clothing is made, design solutions used in clothing on its thermal insulation and clothing size on its thermal insulation properties.
Design/methodology/approach
This study involved laboratory tests of clothing protecting against cold and textile systems used in this type of garment using a “skin model” test stand and a thermal manikin.
Findings
Analysis of the results obtained from tests carried out showed that the design solutions used in a garment can model its local and overall insulation. It was found that using a bib in trousers has a dominant influence on the thermal properties of clothing. An important parameter is also the use of a hood, as well as the length of the jacket. No significant effect of other structural solutions, such as jacket fastening, pockets and reflective tapes, on the thermal performance of the clothing set was noted.
Originality/value
Although the reports available in the literature pay a lot of attention to the impact of the design of clothing protecting against cold on its thermal performance, most of the presented research results relate to the aspects of fit, whereas the analyses of the effects of other aspects of garment construction on thermal properties are lacking. Therefore, the analysis of the impact of design solutions used in clothing on its thermal insulation properties is a key original factor of this paper.
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Youngjoo Na and Jisu Kim
Women in Western Europe wore empire style robes which were made with a light and thin fabric revealing their body. To stress the silhouette of their body, they applied oil to it…
Abstract
Purpose
Women in Western Europe wore empire style robes which were made with a light and thin fabric revealing their body. To stress the silhouette of their body, they applied oil to it or sprayed water on the robe so that it would cling to the body, and most women suffered from muslin disease, meaning flu and tuberculosis of the lungs in winter season. The purpose of this paper is to examine the thermal insulation of the robe with spencer jacket in dry and wet environment through thermal manikin experiments.
Design/methodology/approach
Three kinds of spencer jacket were made based on historical evidence and data, and experimental work for thermal insulation was conducted using a thermal manikin. The study measured the total thermal resistance of dress-jacket set: weight of the clothing before and after wetting, thermal insulation of the spencer jackets and set of clothing in dry and wet conditions, electric power consumption of the set of clothing in the wet condition and temperature inside the clothing and surface temperature of the wet set of clothing.
Findings
The thermal insulation of the robe with spencer jacket in the wet condition was in the range of 0.135-0.144 clo, which was about 80 percent lower than the range of values of 0.73-0.79 clo measured in the dry condition. This means that women felt uncomfortable in wetting condition or raining environment even when wearing the robe with a spencer jacket. Thermal insulation of clothing was dependent to the air gap under garment, clothing layers, ventilation through fabric and body part.
Originality/value
In this study, the thermal insulation of an empire style robe with spencer jacket in wet condition was measured using a dry thermal manikin, not with the sweating manikin. The authors measure the electric power consumption according to drying time of the clothing set at the body parts. In order to study the effect of different materials and clothing wetting, comparison experiments were conducted in dry and wet conditions using the rinse cycle of washing machine.
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Ming Fu, Wenguo Weng and Hongyong Yuan
– The purpose of this paper is to measure the thermal insulation of protective clothing with multilayer gaps in low-level heat exposures.
Abstract
Purpose
The purpose of this paper is to measure the thermal insulation of protective clothing with multilayer gaps in low-level heat exposures.
Design/methodology/approach
Nine different combinations of protective clothing systems with multiple air gaps are used to measure the thermal insulation by a self-designed bench-scale test apparatus in different levels of an external thermal radiation of 2-10 kW/m2. The outside and inside surface temperatures of each fabric layer are also measured to calculate the local thermal insulation of each fabric layer and each air gap.
Findings
The results show that the total thermal insulation of protective clothing under thermal radiation is less than that in normal environments, and the exposed thermal radiation will worsen the total thermal insulation of the multilayer fabric systems. Air gap plays a positive role in the total thermal insulation, and thus provides the enhanced thermal protection. It is also suggested that the local resistance of the air gap closer to the external thermal radiation is more easily affected by the thermal radiation, due to the different heat transfer ways in the fabric system and the external thermal radiation.
Originality/value
Effects of air gap on the thermal insulation of protective clothing, and contribution of the local thermal resistance of each fabric layer and each air gap to the total thermal insulation.
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Joo‐Young Lee, Eun‐Sook Ko, Hyo‐Hyun Lee, Jae‐Young Kim and Jeong‐Wha Choi
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.
Abstract
Purpose
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.
Design/methodology/approach
A total of 150 single garments and 38 clothing ensembles were assessed using the manikin; 26 seasonal clothing ensembles were selected for human trials.
Findings
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.
Originality/value
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.
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Youngjoo Na and Jisu Kim
Empire style fashion, Greek-Roman style robe with bare shoulder and chest and short sleeved with long gloves which created a slim silhouette, was worn even in winter season in…
Abstract
Purpose
Empire style fashion, Greek-Roman style robe with bare shoulder and chest and short sleeved with long gloves which created a slim silhouette, was worn even in winter season in Europe, where average temperature is 0-5°C. Most women suffered with catching cold and thousands caught flu and tuberculosis of the lungs, called muslin disease. The purpose of this paper is to find out clothing insulation of the robe by measuring the thermal resistance and to guess how cold they felt in this robe in winter time.
Design/methodology/approach
The authors performed the investigation on original robe shape with based on historical evidence and data, such as drawings, sketches, pattern books and sewing books, and reproduced a representative robe costume and tested its thermal insulation. The fabrics of robe were thin wool, silk and cotton following the literature evidence and preserved costume. Thermal insulation of the robes was measured using thermal manikin with the test method ISO 15831. The authors analyzed the thermal insulation of reconstructed robes with an inner cotton breech as for daily use and tested them wrapped with cashmere shawl on manikin shoulder as for severe cold weather.
Findings
The dress robes had the range of 0.61-0.67 clo regardless of the type of fabric materials, and 0.80-0.81 clo with the cashmere shawl. These values were not enough for women to keep body temperature or comfort in winter time.
Originality/value
This study combined fashion historic theory for costume reproduction with clothing science and technology for thermal insulation. Combination of costume history, construction technology and measurement engineering is the ingenious idea, and the combination of historical and scientific research evidences interdisciplinary originality.
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J. Fan and J.H. Keighley
A theoretical model for the study of the thermal insulation of clothing in windy conditions is presented. In this model, the trunk of a human body is approximated to as an…
Abstract
A theoretical model for the study of the thermal insulation of clothing in windy conditions is presented. In this model, the trunk of a human body is approximated to as an internally temperature‐controlled hollow cylinder. The clothing assembly covering on the cylindrical body consists of two parts, an outer wind resistant fabric and an inner porous fibrous material. The numerical solution derived agrees well with the experimental findings performed on a cylindrical togmeter in a wind tunnel. It appears that air penetration and changes in clothing geometry caused by compression, expansion or fluctuation of the assembly are two essential mechanisms which cause the wind‐induced reduction in thermal insulation. The effects of wind velocity, air permeability of the outer fabric and inner porous fibrous material, are examined and discussed.
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Wiah Wardiningsih and Olga Troynikov
This paper aims to examine the influence of hip protective clothing on ensemble performance attributes related to thermal comfort. It also explores the effect on protective pads…
Abstract
Purpose
This paper aims to examine the influence of hip protective clothing on ensemble performance attributes related to thermal comfort. It also explores the effect on protective pads of various materials and the arrangements of material. The thermal comfort characteristics are thermal insulation and moisture vapour resistance.
Design/methodology/approach
For this research, four ensembles of clothing were used: one ensemble without hip protective clothing and three ensembles with hip protective clothing. A thermal manikin was used to test the thermal insulation and moisture vapour resistance of the ensembles.
Findings
The findings revealed that incorporating hip protective clothing into the clothing ensembles influenced the thermal resistance and moisture vapour resistance of the ensemble. In the “all zones group,” the influence of the hip protective clothing depended on clothing style, with hipster-style clothing producing insignificant changes. In the “hip zones group” and “stomach and hip zones group,” hip protective clothing strongly influenced the thermal comfort attributes of ensembles. Pad material and volume play important roles in these changes in thermal comfort attributes.
Originality/value
These outcomes are useful for the design and engineering of hip protective clothing, where maximizing protection while minimizing thermal and moisture vapour resistance is critical for wear comfort and adherence in warm or hot conditions. The designer should consider that material, volume and thickness of protective pad affect the overall thermal comfort attributes of the hip protective clothing.
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