Thermal insulation property of spacer fabrics integrated by ceramic powder impregnated fabrics

Abstract

Nowadays, because of limited sources of energy, thermal insulation property is becoming very important for engineers. The main purpose of this work is to investigate thermal insulation property of three-dimensional knitted spacer fabrics integrated by ceramic powder-impregnated fabrics. Ceramic materials are well-known and useful for thermal insulation applications. An apparatus was designed and manufactured for measuring the heat flux through fabrics as well as thermal insulation property. The apparatus consists of a guarded hot plate providing adjustable temperature ranging from 36 to 500℃. In order to measure the fabric cold-side temperature, an infrared thermometer is used. A heat flux sensor is also used to measure the heat flux through samples. To improve thermal property and prevent the air convection through spacer fabric, a three-layered fabric system consisting of a three-dimensional knitted polyester spacer fabric in the middle and integrated by two layers of knitted cotton fabrics impregnated with silica at both sides was constructed. This multilayer construction had a significant effect on increasing the thermal resistance property in comparison to the untreated spacer fabric. A series model was also considered for the thermal resistance of multilayered set. Thermal resistance of each layer was first measured separately and thermal resistance of multilayered set was calculated according to the series model. The total thermal resistance of the set was then measured. The results showed a good agreement with those from series model.