对于纤维增强SiO2气凝胶复合隔热材料的等效热导率,以往主要通过提出简化结构之后利用等效电路方法进行理论求解。本文提出一种纤维结构的计算机随机生成方法,生成了不同的纤维气凝胶复合材料等效结构单元;采用三维格子Boltzmann模型求解该等效结构的温度场,并计算了复合材料常温下的等效热导率。本文数值预测结果与理论计算结果及相关实验结果吻合良好,表明本文模型能够有效地预测纤维-气凝胶复合材料的等效热导率。 The equivalent thermal conductivity of fiber-reinforced SiO2 airgel composite insulation materials was mainly solved theoretically by using the equivalent circuit method after the simplified structure was proposed. In this paper, a random computer generated method of fiber structure is proposed to generate different structural units of fibrous airgel composites. The three-dimensional lattice Boltzmann model is used to solve the temperature field of the equivalent structure. Effective thermal conductivity. The numerical results in this paper are in good agreement with the theoretical calculation results and the related experimental results, which shows that the proposed model can effectively predict the equivalent thermal conductivity of the fiber-airgel composites.