Study And Prediction Of Heat Transfer Performance Of Thermal Textile Considering The Skin Tissue

The clothing with special purposes and functions can not only protect the staffs in bad environment to a great extent,but also provide health care,medical and so on.In order to shorten the research and development cycle of functional clothing,and to make a more accurate evaluation of its thermal performance,more and more researchers have simulated the heat transfer process of functional clothing by the finite element method.On the basis of that,this paper have published two skin tissue laminated structure models that included blood vessels.Considering the interaction of functional clothing,air and skin tissue,a combined heat conduction finite element model of clothing air skin tissue is established.The ANSYS software is used to simulate the steady heat transfer of the joint model.The distribution of temperature field in the skin tissue have been analyzed under the condition of electric heating clothing,thermal protective clothing,aerogel based cold protective clothing and outdoor jacket,so as to provide reference for the design optimization of functional clothing.Firstly,referring to the real situation of human skin tissue,two skin tissue geometric models with different vascular structures are established by using ANSYS in this paper.The rationality of skin tissue layered model with vascular structure is also verified.Secondly,through the simulation of the skin tissue rich in large blood vessels,it is found that the temperature of the tissue around the blood vessels is significantly higher than that of other parts,which shows that the influence of blood perfusion heat production of large blood vessels on the temperature field of biological tissue can not be ignored.Therefore,the distribution of blood vessels in human skin tissue should be considered fully in the simulation of functional clothing.The results show that the initial temperature of blood has a larger effect on the temperature distribution of skin tissue,which the temperature of body is higher than that of limbs.On this basis,the clothing air skin joint model has been established further.The temperature distribution of the combined model is simulated in detail under various conditions,and the thermal performance of four different functional clothing has been analyzed and evaluated.The results shows that: the higher the power of electric vest,the higher the temperature of skin tissue,and the better the thermal effect.From the view of human physiology,local temperature plays an important role in the overall thermal comfort,so more attention should be paid to the local temperature analysis when we are evaluating the thermal comfort of electric heating clothing.In five typical conditions with high temperature,the thermal protective clothing shows good heat insulation effect,and the surface temperature of skin tissue is suitable for human.Both overall heat preservation effect and the local thermal effect of aerogel based cold protective clothing are better than those of the suit in that condition.The skin temperature of the limbs is lower than that of the trunk,so the thermal protection of the limbs should be enhanced in the future optimization design.