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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.

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.

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.

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.

In this paper, a study on the design and development of functional shoe linings that are thermally comfortable is presented. The comfort of foot wear, in this case, trekking boots, that is perceived by the user greatly depends on the ability of the boot to maintain the foot surface in an equilibrium state in terms of thermo-physiological comfort (Schols et al., 2004). This is related to the capacity of removing the moisture that results from transpiration away from the foot surface. With these premises in mind, a study on the development of new lining constructions using different raw materials has been conducted.

As far as methodology is concerned, this study involves two different stages. The first stage includes an objective evaluation of the thermal comfort of the boots. This stage involves several tasks, including the conception and development of the fabrics to be used in the inner layer of the boots and the development of a thermo-physiological model of the human foot, in order to simulate the temperature and moisture behavior in the developed fabrics. The second stage consists of a subjective evaluation of thermal comfort using prototypes of the developed boots. A subjective evaluation assessment was done through a questionnaire, in which the study subjects are able to indicate where they experience thermal discomfort in the foot, as well as a laboratory physical task used to simulate the “real” use of the boots.

The purpose of this paper is to integrate a thermophysiological human body model into a CFD simulation to predict the dry and latent body heat loss, the clothing, skin and core temperature, skin wettedness and periphery blood flow distribution. The integration of the model allows to generate more realistic boundary conditions for the CFD simulation and allows to predict the room distribution of temperature and humidity originating from the occupants.

A two-dimensional thermophysiological body model is integrated into a CFD simulation to predict the interaction between the human body and room environment. Parameters varied were clothing insulation and metabolic activity and supply air temperature. The body dry and latent heat loss, skin wettedness, skin and core temperatures were predicted together with the room air temperature and humidity.

Clothing and metabolic activity were found to have different level of impact on the dry and latent heat loss. Heat loss was more strongly affected by changes in the metabolic rate than in the clothing insulation. Latent heat loss was found to exhibit much larger variations compared to dry heat loss due to the high latent heat potential of water.

Unlike similar studies featuring naked human body, clothing characteristics like sensible resistance and vapor permeability were accommodated into the present study. A method to ensure numerical stability of the integrated simulation was developed and implemented to produce robust and reliable simulation performance.

In cities with high density, heat is often trapped between buildings which increases the frequency and intensity of heat events. Researchers have focused on developing strategies to mitigate the negative impacts of heat in cities. Adopting green infrastructure and cooling pavements are some of the many ways to promote thermal comfort against heat. The purpose of this study is to improve microclimate conditions and thermal comfort levels in high-density living conditions in Seoul, South Korea.

This study compares six design alternatives of an apartment complex with different paving and planting systems. It also examines the thermal outcome of the alternatives under normal and extreme heat conditions to suggest strategies to secure acceptable thermal comfort levels for the inhabitants. Each alternative is analyzed using ENVI-met, a software program that simulates microclimate conditions and thermal comfort features based on relationships among buildings, vegetation and pavements.

The results indicate that grass paving was more effective than stone paving in lowering air temperature and improving thermal comfort at the near-surface level. Coniferous trees were found to be more effective than broadleaf trees in reducing temperature. Thermal comfort levels were most improved when coniferous trees were planted in paired settings.

Landscape elements show promise for the improvement of thermal conditions because it is much easier to redesign landscape elements, such as paving or planting, than to change fixed urban elements like buildings and roads. The results identified the potential of landscape design for improving microclimate and thermal comfort in urban residential complexes.

The results contribute to the literature by examining the effect of tree species and layout on thermal comfort levels, which has been rarely investigated in previous studies.

The water evaporation rate (WER) is not only crucial for fabric drying, but also an important parameter affecting cooling from a body wearing sweat wetted clothing. The purpose of this paper is to predict the WERs of wet textile materials in a pre-defined environment.

The maximum water evaporation rate (WER_max) from a saturated surface in a pre-defined environment was first predicted based on the Lewis relationship between the evaporative and the convective heat transfer in this paper. The prediction results were validated by the comparisons with experimental measurements in various environments obtained in this paper and reported in the literature.

Experiment results show that the ratios of WERs to WER_max are lower than 100 percent but higher than 50 percent, which confirmed that the prediction of WER_max is reliable. The temperature decrease of the wet material surface due to evaporation was considered to account for the difference between measured WERs and the WERmax, and the WER variation among materials. The lower ratios of WERs to WER_max in the higher wind condition were speculated to be due to the greater temperature decrease caused by the increased evaporation.

It provides a reliable way to obtain both WER_max and WER (WER_max multiplied by a proper ratio), which can be useful in clothing physiological modeling to predict clothing comfort.

This study contributes to the understanding of the evaporation process of textile materials.

First, the contributions of spatial characteristics to microclimate were analyzed. And the results from mobile measurements were compared to those from fixed measurements to examine accuracy of mobile method. Air temperature and physiologically equivalent temperature (PET) profiles were plotted to explore the impacts of the spatial characteristics of that urban square and local street.

This research investigates the effects of urban canyons and landscape on air temperature and outdoor thermal comfort in an open square in Seoul, Korea, a city of diverse thermal environments. Mobile field measurements were carried out to obtain local meteorological data based on higher spatial resolution.

On a day in October under clear sky, air temperature and PET differences of up to 1.77 °C and 9.6 °C were observed at 2 p.m. and 3 p.m., respectively. These were mainly from the impact of shading effects caused by surrounding obstacles. The current layout and volume of vegetation in the square seemed not effective for reducing air temperature and improving thermal comfort, which needs further study.

The authors tested a way to investigate time delay when using mobile measurements by correcting measured local data using adjacent meteorological observatory data. The findings of and limitations on mobile station-based field measurement and analysis are discussed herein.

The purpose of this paper is to investigate the thermo-physiological comfort of male business garments made of common textiles, as well as business clothing that contains phase change materials (PCMs) as a lining or outerwear material. In view of the fact that people wear business clothing throughout the whole day in different environmental conditions, this study investigate the effect of PCMs incorporated in male business clothing systems on the thermo-physiological comfort of the wearer under different cold environmental conditions.

The influence of particular business garments on the thermo-physiological comfort of the wearer during different physical activities and cold environmental temperatures was determined experimentally with the help of study participants, as a change of two physiological parameters: mean skin temperature and heart rate. A questionnaire and an assessment scale were also used in order to evaluate the wearer’s subjective feeling of comfort. In this investigation, all tests with study participants were performed under artificially created environmental conditions in a climate chamber at different cold environmental temperatures ranging from 10°C to −5°C with increments of 5°C, and different physical activities that simulate as closely as possible real life activities such as sitting and walking.

The results of the performed research work show that PCMs provide a small temporary thermal effect that is reflected in small increases or decreases in mean skin temperature during changes in activity. Furthermore, it was concluded that the small effect of PCMs in business clothing systems on the thermo-physiological comfort of the wearer in a cold environment, which is shown as a change of mean skin temperature when subjects walk on a treadmill and subsequently move to a sitting position, should not be ignored in a cold environment where low skin temperatures were measured.

The results of this study demonstrate that the physiological parameters of thermo-physiological comfort, in combination with subjective evaluation, provide valuable information for textile and clothing manufactures as well as scientists and engineers involved in the design and development of new products with thermal comfort as a quality criterion.

The investigation shows that different environmental conditions, activity levels and thermal properties of clothing systems have a considerable impact on the physiological parameters of the subjects and subjective assessment of thermal comfort in a cold environment, and that PCMs incorporated in business clothing systems provide a small temporary thermal effect that is reflected in small increases or decreases in mean skin temperature during changes in activity, such as when subjects walk on a treadmill and subsequently move to a sitting position.

The purpose of this paper is to evaluate the thermo‐physiological comfort of a knitted polyester (PES) fabric which contains activated carbon particles in the back‐side.

According to the manufacturer's intention, the activated carbon particles, added in the PES extrusion process, give permanent attributes to the garment, such as odour resistance, UV protection and evaporative cooling. These features should make the modified PES ideal for sportswear. Standard fabric characteristics (morphology, mass per unit area, thickness) have been evaluated for two similar fabrics, the one containing the modified PES yarn and the other one made of conventional PES yarn. The investigated thermo‐physiological properties were air permeability (AP), water vapour resistance (R_et ), thermal resistance (R_ct ), thermal conductivity and diffusion, drying rate, vertical wicking, horizontal liquid diffusion area and buffering capacity. They have been measured in controlled thermal and humidity conditions in a climatic chamber.

The modified fabric is more hydrophilic than the conventional one, thanks to the carbon particles sorption ability. Thus, the liquid management of the modified PES fabric was found to be better. On the other hand, liquid desorption was slow and the drying time was longer. Moreover, the dry heat and the vapour transfer were found slightly worse for the modified PES, probably due to the lower AP.

The paper shows a comprehensive fabric characterization of a functionalized fabric, highlighting the positive and negative effects of activated carbon particles on the liquid, vapour and heat management.

The purpose of this paper is to consider the thermal‐physiological comfort performances of a sport shirt made of a polyester (PES) fabric with incorporated activated carbon. After having characterized the modified PES fabric in Part I, the results of a wear trial campaign are shown and discussed in this work.

The wear trials have been carried out under a controlled physical activity. A short‐and‐intense effort and an intermittent effort of milder intensity were carried out twice by each volunteer: once wearing a shirt made of the modified PES fabric and the other one wearing an analogous shirt made of a conventional PES fabric.

When sweating was moderate, the modified PES shirt was judged as more comfortable on the average. As the effort became harder, the modified PES fabric turned out to be less comfortable than the conventional one. In the final recovery stage, the conventional PES was still more comfortable than the modified PES. This behaviour was justified according to the findings of Part I: at the beginning, the prevailing effect was the adsorbing ability of carbon particles that buffer sweat impulses, giving the user a pleasant dry sensation. Then, when sweating became intense, the lower evaporative cooling of the modified PES fabric became the key factor governing the physiological comfort of the garment. This is confirmed by a slightly higher skin temperature measured during the modified PES fabric trials. Finally, a post‐exercise chill sensation was felt with the modified PES fabric, due to a longer drying time.

The paper presents a comprehensive study of the thermo‐physiological comfort of a fabric containing activated carbon particles.

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.