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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 solutions used in clothing on its thermal insulation and clothing size on its thermal insulation properties.

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.

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.

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.

The purpose of this paper is to deal with performance verification of thermal insulation fillings that are used for outer clothes into cold environments. Thermal properties of filling materials (down and three sophisticated fillings) were tested under condition approaching real weather conditions in Middle Europe.

In the paper, modern method of thermal resistance Rct measurement, by Sweating Guarded-Hotplate system, was compared with method of Technical University of Liberec (TUL method). The TUL method shows good results and it is applicable even at ambient temperatures below zero, which fully corresponds to real application of the insulation filling.

Evaluation of fibre battings were carried out even at temperatures below the freezing point, which is important for simulation of actual application of these filling structures. The highest thermal resistance of goose down confirm that natural materials have their irreplaceable position, especially in application into clothes for extreme conditions.

There does not include effect of the humidity change on thermal insulation properties. It will be subject of further research of authors.

The investigation of thermal insulation properties were carried out under conditions approaching real application of tested materials, namely, at low ambient temperature.

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.

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 purpose of this research is using materials to improve the thermal insulation, and reducing the cost. A large amount of energy is consumed by masonary due to cooling and heating. Adding material with certain percentages to the building materials is one of the ways to improve the thermal insulation, and these additives should keep as much as possible the mechanical properties of the building materials. Carbon additives are one of commonly used materials to masonry materials. In spite of the many advantages of using carbon fibers and carbon nano tubes (CNTs) to the cementitious materials, they are very expansive and their thermal conductivity is high.

In this research charcoal (which is a product of burning process) with very low thermal conductivity and cost in the form of micro particles will be used with mortar and compared with short carbon fibers and multiwall carbon nanotubes (MWCNTs) via thermal conductivity, density and compressive strength tests. This research includes also an effort to build a model of building to evaluate the thermal insulation of the materials used in the practical part. The main building design and performance simulation tool in this research is DesignBuilder.

Results showed that adding micro charcoal particles to mortar resulted in improving the thermal insulation and decrease the rate of reduction in the compressive strength compared to other additives, while adding short carbon fibers resulted in improving the thermal insulation and decrease the compressive strength. Adding MWCNT to the mortar had a negative effect on mechanical and physical properties, i.e. compressive strength, density and thermal insulation.

This paper uses DesignBuilder software to design a model of building made from the materials used in the practical part to predict and evaluate the thermal insulation.

The purpose of this paper is to analyse the seersucker fabrics from the point of view of their ability to ensure the thermo-physiological comfort. It was investigated how the kind of the weft yarn and seersucker structure influence the air permeability and thermal insulation properties of the fabrics.

The paper presents the investigations of the typical seersucker fabrics made of the same set of warps and different weft yarns. Fabrics were manufactured on the same loom with two warp beams. Next they were finished by the same way including washing, drying and stabilisation processes. Fabrics were measured in the range of their air permeability using standard test method. Thermal insulation properties of fabrics were measured in dry and wet state by means of Alambeta. Surface topography of the seersucker fabrics was analysed using 3D laser scanning.

On the basis of the obtained results it was stated that due to the puckered structure the seersucker fabrics are characterised by high thermal resistance, several times higher than the thermal resistance of typical flat woven fabrics. The seersucker fabrics are characterised by very low value of the thermal absorptivity in wet state at the level appropriate for typical flat fabrics in dry state. It confirmed that the seersucker fabrics ensure the physiological comfort. Application of the elastomeric yarn in weft caused significant tightening the fabric structure. It resulted in low air permeability, fabric stiffness and unpleasant hand.

As a limitation of the investigation of the seersucker fabrics in wet state we can mention the surface topography of the fabrics. It made wetting the fabrics difficult before measuring. It is necessary to elaborate precise procedure of preparation of seersucker fabrics before their testing in the wet state.

Performed investigations showed that the seersucker fabrics have a big potential to be comfortable. By an appropriate designing of their structure it is possible to achieve very good comfort-related properties even without application of innovative comfort-oriented yarns.

The originality of the paper is based on the fact that the measurement was performed for the seersucker fabrics. The fabrics are characterised by the unique structure which influences their appearance and utility properties. It caused that they are willingly applied in different kinds of clothing. Till now any results of comfort-related properties of such kind of the woven fabrics have not been published.

Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to improve the thermal insulation performance of polyethylene terephthalate (PET), the SiO₂ aerogel/PET composites slices and fibers were prepared, and the effects of the SiO₂ aerogel on the morphology, structure, crystallization property and thermal conductivity of the SiO₂ aerogel/PET composites slices and their fibers were systematically investigated.

The mass ratio of purified terephthalic acid and ethylene glycol was selected as 1:1.5, which was premixed with Sb₂O₃ and the corresponding mass of SiO₂ aerogel, and SiO₂ aerogel/PET composites were prepared by direct esterification and in-situ polymerization. The SiO₂ aerogel/PET composite fibers were prepared by melt-spinning method.

The results showed that the SiO₂ aerogel was uniformly dispersed in the PET matrix. The thermal insulation coefficient of PET was significantly reduced by the addition of SiO₂ aerogel, and the thermal conductivity of the 1.0 Wt.% SiO₂ aerogel/PET composites was reduced by 75.74 mW/(m · K) compared to the pure PET. The thermal conductivity of the 0.8 Wt.% SiO₂ aerogel/PET composite fiber was reduced by 46.06% compared to the pure PET fiber. The crystallinity and flame-retardant coefficient of the SiO₂ aerogel/PET composite fibers showed an increasing trend with the addition of SiO₂ aerogel.

The SiO₂ aerogel/PET composite slices and their fibers have good thermal insulation properties and exhibit good potential for application in the field of thermal insulation, such as warm clothes. In today’s society where the energy crisis is becoming increasingly serious, improving the thermal insulation performance of PET to reduce energy loss will be of great significance to alleviate the energy crisis.

In this study, SiO₂ aerogel/PET composite slices and their fibers were prepared by an in situ polymerization process, which solved the problem of difficult dispersion of nanoparticles in the matrix and the thermal conductivity of PET significantly reduced.

Fabrics’ thermal properties greatly influence human comfort during wear. For this reason, fabrics with optimum thermal properties need to be developed. This paper aims to investigate the effect of weft yarn twist levels on thermal and surface properties of 100 per cent cotton woven fabrics.

Five types of plain woven cotton fabrics were manufactured using weft yarns with 900, 905, 910, 915 and 920 twists/meter (Tpm). The other parameters of the samples as count, thread density and fabric structures were kept constant. Fabric thermal properties were evaluated by measuring its thermal conductivity, thermal resistance, actual insulation, water permeability, air permeability and wicking ability. The fabric compression and surface properties were also evaluated because they contribute to the overall clothing comfort.

The results showed that actual insulation and thermal resistance property decreased with an increase in twists/meter of the weft yarn. However, thermal conductivity does not significantly change while fabric compression reduced with an increase in twist as the surface roughness increased.

Comfort is a fundamental requirement in human daily existence, and it is greatly influenced by clothing, which comes in close contact with the human skin. Fabrics’ thermal properties greatly influence human comfort during wear. For this reason, fabrics with optimum thermal properties need to be developed.

The purpose of this paper is to present a case study of cracks on external thermal insulation composite systems (ETICS) along the thermal insulation joints and the information available on the building pathology catalogue – PATORREB. The aim is to establish the methodology to study the cause of the pathology observed on a building which is located on the interior of Portugal based on in situ probing together with the analysis of hygrothermal and mechanical behaviour.

An in situ analysis was performed to assess the causes. The hygrothermal dynamic behaviour of the wall was analysed with a numerical simulation advanced tool considering the climatic conditions, the characteristics of the thermal insulation plates as well as the support and finishing layer properties. Moreover, a qualitatively analysis of the mechanical behaviour, based on the bonding process, thermal insulation and exterior rendering properties was performed.

It was concluded that the insulation properties – thermal expansion coefficient and stiffness, the thermal expansion coefficient of the exterior rendering, together with adverse climatic conditions were critical for the appearance of cracks along the plate joints, particularly with spot bonding. The expansion and retraction stresses and the restrained movements of the components can result in bending moments, especially when the insulation material has a high stiffness value, which will create the crack on the rendering system.

A combination between a hygrothermal and mechanical analysis of an ETICS pathology concerning the appearance of cracks with a subsequent integration into a building pathology catalogue.

This study aims to assess the efficacy of thermal analysis of concrete slabs by including different insulation materials using ANSYS. Regression equations were proposed to predict the thermal conductivity using concrete density. As these simulation and regression analyses are essential tools in designing the thermal insulation concretes with various densities, they sequentially reduce the associated time, effort and cost.

Two grades of concretes were taken for thermal analysis. They were designed by replacing the natural fine aggregates with thermal insulation aggregates: expanded polystyrene, exfoliated vermiculite and light expanded clay. Density, temperature difference, specific heat capacity, thermal conductivity and time were measured by conducting experiments. This data was used to simulate concrete slabs in ANSYS. Regression analysis was performed to obtain the relation between density and thermal conductivity. Finally, the quality of the predicted regression equations was assessed using root mean square error (RMSE), mean absolute error (MAE), integral absolute error (IAE) and normal efficiency (NE).

ANSYS analysis on concrete slabs accurately estimates the thermal behavior of concrete, with lesser error value ranges between 0.19 and 7.92%. Further, the developed regression equations proved accurate with lower values of RMSE (0.013 to 0.089), MAE (0.009 to 0.088); IAE (0.216 to 5.828%) and higher values of NE (94.16 to 99.97%).

The thermal analysis accurately simulates the experimental transfer of heat across the concrete slab. Obtained regression equations proved helpful while designing the thermal insulation concrete.