聚氨脂泡沫塑料是一种多孔介质,它的不规则泡孔结构对导热过程有重大的影响.本文利用局部面积分形维数来描述聚氨脂泡沫塑料的泡孔结构,计算了沿发泡方向和垂直发泡方向的局部分形维数,构建了当量元泡.根据截面分形空隙分数,提出了一个计算聚氨脂泡沫塑料导热的简化分形导热模型,导出了多孔泡沫材料分形导热系数的计算公式.模型的预测值与聚氨脂泡沫塑料样品的实测值吻合. Polyurethane foam is a kind of porous media, its irregular cell structure has a great influence on the thermal conduction process.In this paper, the fractal dimension of the area is used to describe the cell structure of polyurethane foam, Direction and vertical foaming directions, the equivalent bubble was constructed.According to the fractal void fraction, a simplified fractal thermal model was proposed to calculate the thermal conductivity of polyurethane foam, and the fractal thermal conductivity of porous foam was derived Calculation formula The predicted value of the model is consistent with the measured value of the polyurethane foam sample.