关键词: 有限元仿真, 导热性能, 参数化建模, 导热系数, 蓄热系数

Abstract: With the growing demand for thermal comfort in textiles, there has been a heightened research focus on fabrics with excellent thermal properties. During hot summers, fabrics with excellent thermal properties can efficiently transfer the body's heat to the external environment, offering a comfortable and cool wearing experience. The thermal properties of fabrics are influenced by factors such as fabric structure, fabric tightness, yarn thermal conductivity, fiber content, and fabric post-processing. Studying these influential factors is important for the development of fabrics with excellent thermal properties.
Traditionally, developing fabrics with good thermal properties involved weaving numerous fabric samples and conducting a series of physical tests to analyze the product's thermal properties, which was time-consuming and wasteful of raw materials. Compared to traditional experimental methods, finite element analysis systems can quickly obtain indicators of fabric thermal properties such as thermal conductivity, thermal resistance, thermal effusivity, and CLO value, making fabric design more effective.
In recent years, scientists have utilized finite element software such as ANSYS and ABAQUS to simulate and predict the heat transfer performance of fabrics. This approach offers an effective means of evaluating and optimizing high-quality, low-cost fabrics. However, the CAE module simulation analysis environment has limitations that make it challenging to directly analyze fabric heat transfer performance and process data. Therefore, this study aimed to develop a system for the finite element simulation of fabric heat transfer using the improved technology of ANSYS/APDL 
Firstly, various fabric samples with different fabric structures, yarn materials, and warp and weft yarn combinations were woven. The parameters of the fabric structure were then measured by using microscopic imaging to create a parametric model. A three-dimensional finite element model of the "environment-fabric-skin" system was then created by using finite element software to simulate the heat transfer process and temperature distribution characteristics of the fabric during wear. This model was also utilized for calculating the thermal conductivity coefficient and thermal effusivity of the fabric. Subsequently, the C-THERM TCi thermal conductivity meter was used to measure the thermal conductivity coefficient and thermal effusivity of the fabric samples. The experimental test results were then compared with the simulation results to validate the efficacy of the model. Finally, the impact of fabric structure, fabric tightness, and yarn thermal conductivity on fabric thermal properties was investigated through finite element simulation.
Comparing the experimental test and simulation results, the absolute error of the calculated thermal conductivity coefficient and thermal effusivity from the simulation is within 4% of the experimental test results, validating the effectiveness of the model. Further exploration of the factors influencing fabric thermal properties reveals that under the same conditions, plain weave fabrics exhibit the highest thermal effusivity and thermal conductivity coefficient, followed by twill weave, with satin weave showing the lowest values. Additionally, under the same conditions, the higher the tightness of fabric is, the more its heat conductivity coefficient and effusivity will be. Similarly, as yarn thermal conductivity increases, there will also be an increase in the fabric's thermal conductivity and thermal effusivity. Hopefully, the research findings can shed a light on the parametric modeling of fabrics and the development of fabric heat transfer finite element simulation systems, and offer insights for the subsequent improvement of fabrics with favorable thermal properties.

Key words: finite element simulation, thermal properties, parametric modeling, thermal conductivity coefficient, thermal effusivity