Study On Human Thermal Comfort And Energy Saving With Personal Heating

With the enhancement of people's awareness of energy conservation and the improvement of thermal comfort requirements,personal comfort system has gradually attracted the attention of scholars at home and abroad for r educing energy consumption and improving thermal comfort level.In this paper,human thermal comfort and energy saving with personal heating are studied through experiments.18 subjects took part in a series of experiments at 14?,16? and 18 ? in an artificial environment laboratory.The experiments were divided into control conditions and experimental conditions.The experimental conditions were with Personal heating equipment,namely electric heating cushions and foot-warmers.They were used to heat the buttocks,thighs and foot.Meanwhile,subjective reactions,such as thermal comfort,thermal preference,thermal sensation and thermal acceptability,were analyzed in comparison with the control conditions without heating equipment at the same temperature.The experiment lasted 70 minutes,including the preconditioning period and the experiment period.After the preconditioning,subjects entered the room when the air parameters were stable,and filled in the questionnaire every 10 minutes.The questionnaire divided the human body into upper body,buttocks,thighs,calves and foot.The results show that electric heating cushions and foot-warmers can significantly improve thermal sensation and comfort.With the use of electric heating cushions and foot-warmers,overall thermal sensation gradually increased tended to be neutral and thermal comfort gradually increases.we also find that personal heating expands the acceptable temperature range.more than 80% of the subjects can accept the indoor environment at 14? with personal heating.In addition,the overall-local thermal sensation evaluation model is established by principal component regression method.and the validity of it is verified by the fitting results of the predicted and experimental values of overall thermal sensation.At the same time,we compare it with other models.The results show that with the heating of electric heating cushions and foot-warmers,buttocks,thighs and feet have a great influence on the overall thermal sensation.Although other p arts are not directly heated in non-uniform cold environment,they also affect overall thermal sensation in varying degrees.Finally,we establish a room model and set relevant parameters by EnergyPlus.energy consumption of split air conditioning plus per sonal comfort system in winter design day and heating season are simulated at different temperatures based on experimental conditions.And it is compared with energy consumption of split air conditioning to determine the energy saving potential of electric heating cushions and foot-warmers.Compared with energy consumption of split air conditioning at 20?,when the room temperature is controlled at 14?,personal heating can save energy by 39.6% in winter design day and 42.3% in heating season.Energy saving rate of electric heating cushions and foot-warmers increases as the temperature reduce.and it is about 7% with the decrease of indoor temperature by 1?.In conclusion,personal heating is an effective way to maintain thermal comfort and save energy.the study will provide some reference for comfort and energy saving of personalized comfort system.