Performance Simulation And Experimental Study Of A New Type Of Human Body Air Conditioning Clothing Based On Thermoelectric Refrigeration

With the increasingly serious phenomenon of global warming,the average daily temperature in summer has increased year by year in many countries and regions.Taking South China as an example,the summer time is generally prolonged,and during this period,it is characterized by high temperature,high humidity,no wind or low wind speed.When the human body works or exercises in this environment,the heat can not be effectively discharged,resulting in increased heat storage and rising body temperature.In serious cases,there will be symptoms such as loss of appetite,inability to concentrate and even heatstroke.Aiming at the outdoor environment in South China in summer,based on the advantages of thermoelectric refrigeration,such as on demand,convenient operation,adjustable and controllable,firstly,based on the principle of thermoelectric refrigeration,the influencing factors of refrigeration effect are analyzed,the type selection design and operation strategy design of semiconductor cooler are carried out,and a new thermoelectric human air conditioning suit is developed.Then,the theoretical heat transfer model of the semiconductor cooler and the human body heat transfer model of the air-conditioning suit are established to predict the heat transfer of the semiconductor cooler with forced convection design and the heat transfer of the local air-conditioning suit.Finally,20 subjects were tested under the environmental temperature of30 ? and the exercise intensity of 2.6met to study the physiological and subjective thermal response differences brought by the air-conditioning clothing to the human body,and finally the conclusion of the use effect of thermoelectric air-conditioning clothing was obtained:(1)Experimental results: compared with those without air-conditioned clothing under the same conditions,wearing air-conditioned clothing will make a significant difference in the average skin temperature and back temperature of the human body,and wearing air-conditioned clothing can reduce the average skin temperature and back temperature of the human body,in which the average skin temperature can be reduced by 7.6% at the highest and the back temperature can be reduced by 6.2% at the highest;The individual results of the subjects showed that the thermoelectric air-conditioning suit had a significant cooling effect on 85% of the subjects in the experiment;At the same time,after wearing air-conditioned clothes,the average thermal sensation vote decreased by 5?12%.It shows that the air-conditioning suit can improve the subjective thermal evaluation level of human body during daily activities in summer.(2)Based on the experimental results,the linear regression equations of human skin temperature,TSV and TCV are established.It is found that the slope of the curve when the air-conditioned clothes are not worn is greater than that when the air-conditioned clothes are worn.It shows that the thermoelectric air-conditioned clothes developed in this paper can effectively reduce the thermal reaction discomfort caused by the rise of skin temperature during exercise,so as to improve the comfort during the overall exercise process.(3)The numerical simulation evaluation system for such local cooling equipment as thermoelectric air-conditioning suit is established,which is in good agreement with the experimental results,and can provide reference for the design of similar equipment in the future.