Structural Design Of Far-infrared Radiation Heating Fabric And Simulation Analysis Of Dynamic Electro-thermal Conversion Process

The cold weather causes great inconvenience and even trouble to people in the winter,especially for those working in low temperature environment,the elderly,the weak and sick.The problem of warming in winter is urgently needed to be solved.With the gradual improvement of modern technology and living standards,people’s quality of life is getting higher,and all kinds of heating and daily necessities are increasingly emerging.Traditional electric heating products have some disadvantages such as unstable heating,uneven heating,high energy consumption,and potential safety hazard.Therefore,the exploitation of heating fabrics with rapid heating and uniform heat generation to address the warmth problem in the cold winter has become a research hotspot for researchers.The far-infrared radiation heating fabrics are applied to human body garments,which not only provides extra heat,but also reduces the thickness or weight of winter garments such as heavy down jackets,and enhances the flexibility and convenience of human activities.It can also be used to prepare thermal insulation materials and health care products with broad and bright prospects.In order to effectively improve the electrothermal conversion efficiency of electric heating products,we need to understand the theory of electrothermal conversion process,and the flow of current in the fabric,as well as the distribution of temperature in the fabric.However,the electrothermal conversion process is difficult to be observed directly by testing.Therefore,we need to model and numerically simulate the fabric,understand the flow of electricity in the fabric and the generation and distribution of the heat,and analyze the dynamic electrothermal conversion process of the fabric,so as to effectively improve the electrothermal conversion efficiency.In this paper,carbon nanofibrous membranes were prepared by PAN polymer using electrospinning technology.The far-infrared radiation heating fabrics were constructed with combined carbon nanofibrous membranes and polyester fabrics.We mainly investigated the doping ratio of far-infrared particles and the influence of external voltage on the performance of far-infrared radiation heating fabric.Finally,it was found that 20%SiO₂/15%Tourmaline@CNFs exhibited the best performance among different samples with different formulations.Specifically,the far-infrared radiation heating fabric prepared therefrom could be rapidly heated by 20-30°C within30s.And the composite fabric integrated with a carpet can rapidly heat up to 40°C in1min at 26V.It can be expected that the far-infrared radiation heating fabric can be widely applied in the fields of individual warmth,physical therapy,biomedical treatment and wearable flexible electronics,which has very bright development prospect.In order to further explore the dynamic electrothermal conversion process of far-infrared radiation heating fabrics,the mathematical modeling and visual simulation analysis were carried out by using COMSOL Multiphysics software.The effects of the resistivity parameters of the carbon nanofibrous membranes and different voltages applied on the electrothermal conversion process of the far infrared radiation heating fabric were simulated.By observing the surface temperature,current density and isothermal surface,the simulation results are basically the same compared with the experimental data,indicating that the results of the simulation study are reliable and in close agreement with the practical experimental data.This study shows that the far-infrared radiation heating fabrics have the advantages of rapid heating,stable heat generation,and have broad development value and application prospects.