Thermal Comfort Evaluation Of The Chinese Elderly

Old people are more vulnerable to thermal-related comforts and health issues because of their weakening abilities to perceive and adapt to ambient thermal environment.As a consequence,health and even life may be at risk.It calls for building a healthy and comfortable indoor environment for the elderly,thus it's essential to accurately evaluate thermal comfort of the older people.The thermal comfort model,as an effective means,should be expanded to consider the needs of the elderly and other special groups.The first step of the thermal comfort model is a thermoregulation model for the prediction of body temperatures.Therefore,a standard thermoregulation model was developed based on published findings on the Chinese elderly.Considering the huge individual differences among older individuals,the standard model was individualized with four parameters(height,weight,sex and age).Both the standard and individualized models were validated with experimental data.For the standard model,the difference of the mean skin temperature between predictions and measurement ranged from 0.16 ~oC to0.57 ~oC,and most of local skin temperatures were in the range of the measurement,and the accuracy of the model was 85%to 90%.Adopting individual characteristics in the model notably improved the predictions of the most skin temperatures,and the prediction-measurement discrepancies of the most local skin temperatures were less than 1 ~oC.The result of further validations with published experimental data indicated predictions were also in good agreement with measurement.Furthermore,possible applications of the model were explored.The difference in skin temperature between the thorax and foot could be used to roughly estimate whether Chinese old people are comfortable,and the newly established model can predict it precisely.According to our research,for the uniform indoor environment and the natural ventilation indoor environment,the skin temperature differences between the thorax and foot of the Chinese elderly were generally between 1.7 to 2.6 ~oC and 1.0 to 1.5~oC when indoor temperature in the summer near the thermal neutral temperature range.