Investigation of influence mechanism of temperature-controlled mattress on human thermal comfort in winter

LI Xiaxia;SHEN Liming;GAO Jingshu;Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University;

temperature-controlled mattress;;human-mattress interface temperature;;bed microclimate temperature;;thermal comfort;;sleep quality

In order to investigate the effects of temperature-controlled mattress on the human comfort and sleep quality and to obtain appropriate bed microclimate temperature during sleep,a temperature-controlled mattress with built-in circulating water pipes( WP) and a temperature-controlled mattress with an integral water cushion( WC) were designed and manufactured. The corresponding setting temperatures of the manufactured mattress were 29 ℃ and 32 ℃( hereinafter referred to as WP29,WP32,WC29 and WC32),respectively. A series of sleep experiments were conducted in a real bedroom environment,using the temperature-controlled mattress and a quilt. The target bed microclimate temperature and sleep time were tested and recorded,as well as the subjective thermal response before and after the sleep. The results indicated that WC29 offered lower human-mattress interface temperature and bed microclimate temperature during the sleep,and the thermal sensation remained slightly cool level,which resulted in the lower sleep efficiency. The thermal sensation of WP29 remained thermal neutral level,while those of WP32 and WC32 were slightly warmer level,and the bed microclimate temperature affected by WP32 was the highest. Furthermore,the neutral or slightly warmer bed microclimate offered the better human thermal comfortable and thermal acceptable,resulted in higher sleep efficiency. Moreover,the bed microclimate temperature,thermal sensation and sleep quality affected by WC29 were significantly different from WP29,WP32 and WC32,while that of WP32 was no noticeably different from WC32. There was also significant correlation between overall thermal sensation and sleep parameters,and slightly warm or cool thermal sensation can obviously affect sleep quality. Based on the sleep efficiency,the bed microclimate temperature and overall thermal sensation,it was concluded that the appropriate temperature range of bed microclimate remained 31.45-32.50 ℃,and the satisfaction rate of subjects can be up to 85%. In addition,the temperaturecontrolled mattress with an integral water cushion had obvious effect on the bed microclimate.