بررسي رفتار حرارتي منسوجات بي بافت پوشش داده شده با پودرهاي سراميكي

چكيده انگليسي :

Investigation into thermal behavior of ceramic coated nonwovens Mahbube Pashaei m pashaei@tx iut ac ir Date of Submission 2013 20 01 Department of textile Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Mohammad Ghane m ghane@cc iut ac ir Abstract Concerns for energy conservation have contributed to the need for thermal insulation materials High energy cost has resulted in the use various textile structures to be used as energy saving products due to their insulating properties to be selected as suitable insulating materials Nonwoven fabrics are generally the preferred material for thermal insulation applications Thermal insulating ability of porous materials such as textiles is governed by their internal pores Thermal properties of fabrics are affected by thermal conductivity of constituent fibers fabric bulk density porosity and structure In this project the effect of needled fabric structural parameters on heat transfer properties and the effect of additional coating of the fabric with ceramic powder on thermal insulating ability of the treated fabrics were investigated Structure of the experimental samples was varied by production parameters such as punch density and depth of needle penetration Needled samples using punch densities of 90 110 120 135 150 per cm and depth of needle penetration of 10 13 15 17 19 mm were prepared Samples were made using 17dtex 90 mm long commercially available melt spun polypropylene fibers The thermal conductivity of the samples was measured using a guarded hot plate device In order to measure the sample cold side temperature an infrared thermometer was used A heat flux sensor was also used to measure the heat flux through samples It was found that coating of the samples with ceramic powder tended to improved nonwoven samples thermal insulation properties In order to improve nonwoven thermal insulation three types of ceramic powders i e silica SiO2 alumina Al2O3 and silicon carbide SiC and two type of binders in form of latex and wax were used to bond the powder to the fibers Prepared coating material was added to the samples using painting brush Samples were coated on one side or both sides Thermal conductivity of single and multi layered coated samples was measured using guarded hot plate apparatus Results were evaluated by SPSS software Results showed that thermal conductivity decreases with increase in the thickness and porosity of nonwovens Thermal conductivity also increased with increase in punch density and depth of needle penetration during needling operation The thermal conductivity of samples was determined theoretically and the results were compared with those obtained experimentally Acceptable correlations between theoretical and practical results were observed In comparison to one sided treated samples the two sided treated samples exhibited superior thermal insulation ability I was found that silicon carbide imparts higher insulating ability than the other ceramic powder As far as binders are concerned it was concluded that samples treated using latex binder performed better thermal insulation properties than wax treated samples In case of multi layered samples Results showed that compounded sample using coated samples treated on two sides and one side by silicon carbide and latex exhibited the highest thermal insulation The compounded multi layered nonwoven could reduce temperature from 60 C on the hot plate to 35 C on the nonwoven cold side Keywords Nonwoven Thermal conductivity Guarded Hot plate device Ceramic powderPDF created with pdfFactory trial version www pdffactory com

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بررسي رفتار حرارتي منسوجات بي بافت پوشش داده شده با پودرهاي سراميكي

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