Thermal and water vapor transmission through porous warp knitted 3D spacer fabrics for car upholstery applications

This paper deals with water vapor transmission and thermal properties of various warp knitted spacer fabrics. In this work, thermal and water vapor permeability of different spacer fabrics have been evaluated by varying the structure, areal density, thickness, type of raw materials, etc. The air permeability and water vapor transmission of the fabrics were measured using the Textest FX-3300 air permeability tester and PERMETEST. The thermal behavior of fabrics was evaluated by Alambeta instrument. Analysis of Variance (ANOVA) was performed using new statistical software in order to compare the influence of different fabric parameters on thermo-physiological behavior of samples. This study established that the raw materials, type of spacer yarn, density, thickness, and tightness of surface layer have significant influence on thermal conductivity in spacer fabrics. The parameters which mainly influence the water vapor permeability of these fabrics are porosity, density, and thickness. The empirical model for thermal conductivity calculation shows very high accuracy when compared with experimental results. The statistical model for spacer fabrics also predicts the thermo-physiological properties with very high accuracy. These findings are important requirements for further designing of spacer fabrics for car seats and back supports.