The study of the thermal comfort of the feet when using a specific type of shoe is of paramount i... more The study of the thermal comfort of the feet when using a specific type of shoe is of paramount importance, in particular if the main goal of the study is to attend to the needs of users. The main aim of this study was to propose a test battery for thermal comfort analysis and to apply it to the analysis of trekking boots. Methodologically, the project involves both objective and subjective evaluations. An objective evaluation of the thermal properties of the fabrics used in the boots was developed and applied. In addition, the thermal comfort provided when using the boots was also assessed both subjective and objectively. The evaluation of the thermal comfort during use, which was simulated in a laboratory environment, included the measurement of the temperature and moisture of the feet. The subjective assessment was performed using a questionnaire. From the results obtained, it was possible to define an optimal combination of fabrics to apply to trekking boots by considering the provided thermal insulation, air permeability and wicking. The results also revealed that the subjective perception of thermal comfort appears to be more related to the increase in temperature of the feet than to the moisture retention inside the boot. Although the evaluation of knits used in the boots indicated that a particular combination of fibres was optimal for use in the inner layer, the subjective and objective evaluation of thermal comfort revealed that the evaluation provided by users did not necessarily match the technical assessment data. No correlation was observed between the general comfort and specific thermal comfort assessments. Finally, the identification of thermal discomfort by specific foot areas would be useful in the process of designing and developing boots.
ABSTRACT Bearing in mind that undergraduate students must get involved in research and that local... more ABSTRACT Bearing in mind that undergraduate students must get involved in research and that local industry must be a university partner, the School of Engineering, from University of Minho, has taken the initiative in funding some technical research projects in specifically defined areas (http://www.eng.uminho.pt). In this context, one of the projects founded concerns the development and testing of functional knitting which can be used with success in the lining of a shoe. The study of shoe comfort is of great importance to sport and leisure footwear manufactures, because in these particular situations, moisture disposal over a number of hours is a main problem. Three structures which combine different raw materials (soybean fiber, bamboo fiber, corn fiber, cotton, polypropylene and polyester) have been manufactured by a local textile factory. A group of students mainly from Mechanical and Textile Engineering classes are currently testing these knitting in terms of their water vapor and air permeability and other physical parameters at the laboratory. Tests with a thermal manikin have been used to measure its thermal insulation. A transient model for heat and mass transfer in a fabric has been implemented. From the solution, temperature and vapor density profiles in the fabric thickness can be obtained as well as, the amount of water dissolved in the fabric. This model has been integrated with an existing human thermal comfort model. Thermal comfort surveys are now being made at the Ergonomics Laboratory of the University of Minho with undergraduate Mechanical and Industrial Engineering students, wearing sport shoes manufactured by a local footwear factory, and these results can be compared using statistical analysis, with the experimental and numerical results already obtained.
The study of the thermal comfort of the feet when using a specific type of shoe is of paramount i... more The study of the thermal comfort of the feet when using a specific type of shoe is of paramount importance, in particular if the main goal of the study is to attend to the needs of users. The main aim of this study was to propose a test battery for thermal comfort analysis and to apply it to the analysis of trekking boots. Methodologically, the project involves both objective and subjective evaluations. An objective evaluation of the thermal properties of the fabrics used in the boots was developed and applied. In addition, the thermal comfort provided when using the boots was also assessed both subjective and objectively. The evaluation of the thermal comfort during use, which was simulated in a laboratory environment, included the measurement of the temperature and moisture of the feet. The subjective assessment was performed using a questionnaire. From the results obtained, it was possible to define an optimal combination of fabrics to apply to trekking boots by considering the provided thermal insulation, air permeability and wicking. The results also revealed that the subjective perception of thermal comfort appears to be more related to the increase in temperature of the feet than to the moisture retention inside the boot. Although the evaluation of knits used in the boots indicated that a particular combination of fibres was optimal for use in the inner layer, the subjective and objective evaluation of thermal comfort revealed that the evaluation provided by users did not necessarily match the technical assessment data. No correlation was observed between the general comfort and specific thermal comfort assessments. Finally, the identification of thermal discomfort by specific foot areas would be useful in the process of designing and developing boots.
ABSTRACT Bearing in mind that undergraduate students must get involved in research and that local... more ABSTRACT Bearing in mind that undergraduate students must get involved in research and that local industry must be a university partner, the School of Engineering, from University of Minho, has taken the initiative in funding some technical research projects in specifically defined areas (http://www.eng.uminho.pt). In this context, one of the projects founded concerns the development and testing of functional knitting which can be used with success in the lining of a shoe. The study of shoe comfort is of great importance to sport and leisure footwear manufactures, because in these particular situations, moisture disposal over a number of hours is a main problem. Three structures which combine different raw materials (soybean fiber, bamboo fiber, corn fiber, cotton, polypropylene and polyester) have been manufactured by a local textile factory. A group of students mainly from Mechanical and Textile Engineering classes are currently testing these knitting in terms of their water vapor and air permeability and other physical parameters at the laboratory. Tests with a thermal manikin have been used to measure its thermal insulation. A transient model for heat and mass transfer in a fabric has been implemented. From the solution, temperature and vapor density profiles in the fabric thickness can be obtained as well as, the amount of water dissolved in the fabric. This model has been integrated with an existing human thermal comfort model. Thermal comfort surveys are now being made at the Ergonomics Laboratory of the University of Minho with undergraduate Mechanical and Industrial Engineering students, wearing sport shoes manufactured by a local footwear factory, and these results can be compared using statistical analysis, with the experimental and numerical results already obtained.
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