Design And Evaluation Of Electric-heating Outdoor Clothing For People With Mobility Challenge

For people with mobility challenge,one of the difficulties in outdoor travel and activities in autumn and winter is to keep warm.Compared with traditional clothing,Electric heating clothing can actively heat and providing wearers with different warming options,reducing the risk of frostbite.The design of electric heating outdoor cold protection clothes for them can improve the possibility and convenience of outdoor traveling.However,they both have limited mobility and weakened ability of feeling high temperature,which means they are also susceptible to scalds.Therefore,when designing electric heating clothing for them,it is necessary to give full consideration to both the heating effect and safety.Based on this goal,this paper first discussed the safety range of the heating temperature,and designed an overheat protection device with 45 ? as the overheat warning value.Subsequently,local heating areas were selected including ankles,knees,and lower back.Considering the factors of maximum heating temperature,power limitation and other factors,production plan of the electric heating plate was made.After the production was completed,the heating rate and heating uniformity of the electric heating plate was tested in the bare state to ensure the heating effect and avoid the defects of excessive temperature,the experimental results showed that the electric heating plate heats up faster,and the uniformity of heating was qualified.Then,according to the design principles of the cold-proof clothing,the selection and integration of the electric heating clothing surface accessories were carried out,and the production of the whole clothing was completed.In order to ensure the safety of heating,the heating temperature test of the electric heating suit was carried out again.The temperature of the inner surface of the heating plate of the electric heating suit was tested this time.The experimental results showed that the maximum temperature on the inside was about 45.3 ° C,which was still within the acceptable safety range.After completing the production of electric heating clothing,in order to explore the heat transfer of the electric heating fabric combination under low temperature environment,calculate and predict the temperature distribution of its inner and outer surfaces,a three-dimensional model of the electric heating plate and fabric combination was established by using ABAQUS to calculate and simulate different models under different conditions and obtain the temperature field distribution on the inner and outer surfaces and cross-sections.The simulation results showed that the lower the ambient temperature,the lower the temperature that the electric heater reached when only the ambient temperature was changed;the output power was more,the electric heater The temperature that can be reached higher accordingly,and the power could be selected reasonably according to the wearing environment;with the increase of the thickness of air layer,the temperature of the outer surface became lower and less heat was lost.The increase of thickness of the air layer appropriately could also improve the ability of keeping wearer warm;Considering the compound heat transfer in the air layer,the equivalent thermal conductivity of the air was modified to simulate the convection and other heat transfer in the air layer,the result showed that as the equivalent thermal conductivity of the air increases,the area of heat transfer in the model extended,and the heat transfer between the air was promoted in the horizontal direction.