Investigation on the total and local thermal insulation of the bedding system: Effects of filling materials, weights and body postures

Abstract

Thermal-insulating property of a bedding system plays a key role in affecting the sleeping thermal comfort of human body. This paper examined the impact of filling materials on the total thermal insulation of bedding system using a thermal manikin. Both the total and local thermal insulation of six down bedding systems and under four body sleeping postures were also analyzed. Besides, empirical equations for predicting the total thermal insulation of the bedding systems were developed. It was found that the total thermal insulation of bedding system with down filling was significantly higher than those of silk and wool fillings. Moreover, the total thermal insulation of the bedding system increased nonlinearly with the increasing filling weights for the sleeping postures except the supine sleeping with arms outside the quilt, which shows no thermal insulation increase above the filling weight of 600 g. The total thermal insulation measured in crouching sleeping posture was the largest, and that in supine sleeping with arms outside was the lowest, and no difference was detected between the supine sleeping and sideways sleeping postures for the different filling weights. Besides, the local thermal insulation of the bedding system is affected by the sleeping postures, quilts' filling weights and their interaction effect. This study provides solid guidelines for designing or selecting the bedding systems, and also contributes to enriching the bedding system's total and local thermal insulation database.