Numerical Simulation Study On The Influence Of Structural Parameters On The Thermal Insulation Properties Of Glass Fiber Fabrics

To design a new kind of thermal protection fabric,experimental method is usually used to determine the structural parameters of the fabric.However,the experimental method requires a large number of samples,the experimental cycle is long.In particular situation,some experiments need to be carried out under high temperature conditions,experimental conditions is difficult to control,the operation process has a certain risk,increasing development costs.With the development of computer technology,the heat transfer numerical simulation method is used to optimize the fabric structure parameters,with advantages of fast,safe and environmentally friendly and low cost.It can quickly find the critical value of fabric structure parameters,which provides important theoretical basis for designing,optimizing and applying glass fiber fabric in thermal protection field.In this paper,a three-dimensional geometric model of glass fiber woven fabric was established.The heat transfer boundary condition was defined according to the specific environment.Heat load was applied to the fabric and the heat transfer process in the fabric is solved by the Fourier law,the Newton cooling equation and the law of conservation of energy,the distribution of the temperature field in the fabric under transient 'conditions is obtained,the heat transfer numerical model in the fabric is established.To verify the fabric heat transfer model,the experimental method was used.Then the effects of the structural parameters of the glass fiber fabric on their heat transfer performance are obtained by using the heat transfer numerical model.The results are shown below:(1)In the case of the same warp and weft density of the fabric and yarn fineness,the results show that thermal insulation properties of the samples is in the order as follows:plain weave<2/1 twill<2/2 twill<2/3 twill<3/3 twill fabric.(2)With the same yarn density and weave pattern and yarn fineness,increasing the warp density from 110 ends/10 cm to 160 ends/10cm,the temperature on fabric surface rises slowly,which leads to a significant decrease in heat transfer performance.When the density of the fabric is 160 ends/l0cm,the temperature of the glass fiber fabric is the slowest and the heat insulation property of the fabric is the best.But when the warp density continues to increase to a certain level(160 ends/10 cm),the thermal insulation property shows a decreasing trend with an increase in warp density,the heat insulation property of the fabric is decreasing.(3)When the fabric density and weft density and weave pattern were held constant,with the yarn linear density increased from 129 tex to 280 tex,the insulation properties of the glass fiber fabric increases,and then decreases with the fabric yarn linear density greater than 280 tex.(4)The optimum value of the structural parameters of the glass fiber fabric are:the fabric is 3/3 twill,the warp density is 160 ends/10 cm,the linear density of the yarn is 280tex.