The Study Of Fabric Contact Cold And Warm Feeling And Fiber Thermal Conductivity

Fabric contact warm-cool feeling is the scope of contact comfort,when the fabric and the skin in contact with the moment,the temperature difference between the two will make the skin temperature is increase or decrease,the main form of heat exchange is heat conduction,thermal radiation and natural convection within the fabric of the heat exchange effect form are small and negligible.From a physical sense,the intensity of contact with the strength of cold and warm,it is depending on the fabric and the human body contact with the process of walking away and keep the number of human heat.The temperature of the skin is decreases or increases after the contact of the fabric with the skin,but when the temperature of the skin drops or rises above a certain limit,a feeling of discomfort such as coldness or sultry occurs.Therefore,the fabric contact warm-cold feeling will directly affect people’s consumption concept in different seasons,usually in summer need to contact cool sense of fabric,winter need to touch the warm feeling fabric.In the era of continuous pursuit of fashion and beauty,fabrics of light and functional is particularly important,the purpose of this topic is to explore and develop high thermal conductivity of the fiber.To explore the cold and warm feeling when the skin contact with the fabric,need to discuss the impact of cold and warm feeling of fabric factors.The influences of the thermal conductivity and specific heat capacity of the fabric materials on the contact cold-warm feeling were analyzed from the view of physics.The surface structure,fabric structure,fabric thickness,fabric moisture content and fabric porosity were analyzed from the view of fabric structural parameters.The influence of temperature and humidity of the external environment on the cold-warm feeling of fabric contact was analyzed from the environmental angle.The thermal conductivity of single fiber and fiber aggregate is the basis of research on the heat transfer performance of textiles,and it is of great significance to develop textiles with significant heating and cooling effect and special heat transfer performance.In addition,direct testing of thermal conductivity is a challenging problem in the field of physics testing,because of the large aspect ratio and small diameter(below 100 μm)of a single fiber.Based on the existing testing technology,it is an important problem to explore how to obtain the thermal conductivity and specific heat capacity of conventional fiber through testing.The thermal conductivity of the composites was measured by the TPS method,the thermal conductivity axial and radial directions of the single fibers were obtained by the series-parallel physical model.For different yarns,for example,core-spun yarn,blended yarn,metallized yarn and UHMWPE series fiber,etc.,were tested and analyzed theoretically.The results show that it is feasible to measure the thermal conductivity of the fiber by using this method,and the thermal conductivity of the fiber in the axial direction is obviously larger than that in the radial direction of the fiber,the heat conduction of the fiber has obvious anisotropy.The thermal conductivity of the epoxy-fiber composite was measured by the difference of the thermal conductivity,the volume ratio of the fibers,the equivalent physical model,the heating power of the instrument and the setting of the test time.When the thermal conductivity of the fiber and resin is quite different,the parallel model calculation is more accurate.As the fiber volume fraction increases,the thermal conductivity of the epoxy-fiber sample is increases until equilibrium.Therefore,when the fiber volume ratio exceeds 50%,the results are more accurate.With the increase of heating power and test time,the thermal conductivity of the two-phase composite system was increases.