Simulation Of Skin Damage Caused By Fabric Friction In Marathon

Nowadays,China’s marathon campaign is growing rapidly with a spurt in the number of runners.Marathons are open and inclusive with a wide age range of participants and an increasing number of non-professional runners joining the sport.Marathons are long,extreme sports over long distances,and the continuous single reciprocating motion of the participants can cause skin damage.In order to simulate the dynamic friction process between fabric and skin in marathon sports and to investigate the factors influencing skin damage in marathon sports,this paper establishes a finite element model of fabric-skin friction and a regression prediction equation,using thigh skin as the object of study.The research content and results mainly include the following four aspects.(1)Study of skin and fabric structure as well as mechanical and thermal properties.The friction between skin and fabric is a process of thermal coupling,involving relevant mechanical and thermal parameters.In this paper,the Poisson’s ratio,modulus of elasticity,coefficient of thermal conductivity,and specific heat capacity of the fabric were measured,and the cross-sectional contour of the fabric was extracted by curve fitting for abstract extraction.Finally,the coefficient of friction between the fabric and skin was determined,and the skin parameters were determined from the literature.(2)Development of a thermodynamically coupled finite element model to simulate the friction between skin and fabric in marathon sports.When the fabric rubs against the skin in a marathon,the skin is deformed elastically and subjected to large deformation displacements and friction forces,causing discomfort to the runner.As the friction progresses,the surface cells of the skin are gradually worn away and shed,and the skin temperature rises,leading to erythema,which eventually damages the skin.Therefore,based on the ABAQUS finite element software,this paper builds a thermodynamically coupled finite element model of fabric-skin friction based on the measured mechanical and thermal parameters of skin and fabric,as well as the friction behavior in marathon sports,setting up the interaction between fabric and skin and boundary conditions,and calculating the friction force,displacement and skin temperature of the skin.(3)Timing prediction for marathon sports.In order to relieve the computational pressure of the finite element model,the MATLAB curve fitting toolbox was used to construct a regression prediction equation for the data of skin temperature,friction and deformation displacement in marathon,and the LSTM neural network was used for the timing prediction.(4)Analysis of factors influencing skin friction injury in marathon sports.The paired-sample T-test showed that the friction force,deformation displacement,and temperature of the skin changed significantly over time.A two-factor ANOVA revealed significant differences among the six fabrics,and finally a gray correlation analysis revealed that the most important factors causing frictional damage to the skin were thickness,thermal conductivity,and roughness.The finite element model of fabric and skin friction established in this paper can provide ideas for the future mechanical analysis between the garment and the human body,provide reference for the design of the marathon participant’s garment,provide theoretical basis for strengthening the injury protection in the marathon movement,so as to slow down the damage of fabric friction to the skin,and also provide reference for the friction problems arising in the process of daily garment wearing,which has certain theoretical value and social significance.