Chamber Study On Thermal Adaptation In Winter In Severe Cold Area

It is long in winter in severe cold area, the heating period is more than six months.Now the room temperatures in many residential and office buildings are high in winter,people have to open windows to reduce indoor temperature to achieve comfort, whichinduces energy waste for heating. In order to determine the appropriate indoor eatingtemperature in severe cold area, traditional radiator heating thermal environment in thearea in a microclimate chamber is simulated. The influences of outdoor climate changeand indoor thermal environment to the human thermal adaptation were studied, in orderto provide theoretical basis for the sustainable designing of health, comfort and energyconservation indoor heating environment.30healthy college students participated in the tests as subjects. Humanphysiological and psychological thermal responses of different winter heating periodswere studied in the microclimate chamber. During the experiment, the subjects woreunified winter clothing with thermal insulation of1.01clo. Environment parameterswere measured, such as air temperature, humidity, air speed, surface temperature, blackball temperature etc. Physiological parameters were measured, such as the subjects’ skintemperature, heart rate, blood pressure and weight and other. At the same time, subjectsfilled in the subjective questionnaires.The results show that the same room temperature, human thermal sensation votesin mid-heating period is higher than the thermal sensation in the initial heating period,the calf is most sensitive to the change of outdoor temperature, the thermal sensation inthe initial heating period is little different from the thermal sensation in the terminalheating period. Wholebody thermal comfort is close to the most uncomfortable part ofhuman body (calf), which follow the “complaint” mode. Skin temperature, bloodpressure and skin wetness have no significant differences in different heating periods.Thermal comfort, skin temperature and heart rate have good linear relationships withthermal sensation votes. Considering thermal comfort and energy saving, the suitableheating temperatures in different heating periods were presented.In neutral environment, physiological adaptation had no significant effect onhuman thermal responses. As winter outdoor air temperature decreased, it will be moreeasy for people to accept cold environment psychologically, people feel warmer withthe same indoor environment. With outdoor air temperature gradually raised, thermalsensation votes almost unchanged with the same indoor environment. It declared thatpeople adapted fast to the reducing of outdoor air temperature, but adapted slowly to therising of outdoor air temperature.The heart rate had significant difference in different heating periods. When outdoortemperature is different, while indoor temperature is same, the subjects’ heart rate in the mid-heating is higher than that in the initial and terminal heating periods. The heart rateincreased as indoor temperature rising. The variations provide evidences forphysiological adaptation to outdoor climate and indoor environment.The stepwise regression method is adopted to get the relationship between localand whole thermal sensation. And a model to predict thermal sensation in radiatorheating environment was established. Considering the uniformity of hermal sensationand the influence of whole thermal sensation, a phased synthesis thermal acceptabilityevaluation model and a thermal acceptability evaluation model with thermal comfortwere proposed.