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采用有限单元法,模拟了换热表面污垢随机孔隙的微尺度空间结构,并通过ANSYS中的APDL参数化语言赋值材料参数和单元属性.基于多孔介质在传热过程中能量守恒定律和傅里叶导热定律,提出一种计算换热表面污垢等效导热系数的方法.应用稳态平板法求解污垢内部的耦合导热,并证明通过稳态平板法求解污垢微观模型等效导热系数具有较高的可行性.探索了在不同孔隙率和不同孔隙尺寸的情况下,污垢微观孔隙结构对污垢等效导热系数的影响.结果表明,污垢模型的等效导热系数随孔隙率的增加而线性减小,随孔隙尺寸的增加而线性增加.为换热器设计和清洗带来方便,同时为进一步深入研究复杂的换热表面污垢传热传质过程开辟了新思路,使计算结果更符合实际情况.“,”Micro-scale random pore spatial structure of heat exchange surface fouling was simulated by using the finite element method,and then material parameters and cell properties were assigned by APDL parametric language of ANSYS.Based on the energy conservation law and the Fourier heat transfer law of porous media,a method for calculating the equivalent thermal conductivity,of heat transfer surface was proposed.The coupled heat conduction of fouling was studied by the application of steady-state plate method,and it is proved that the effective thermal conductivity of fouling micro model is feasible by the method of steady-state plate.Furthermore,the influence of micro-scale pore on the effective thermal conductivity of fouling was analyzed under various conditions of porosity and pore size.The results showed that the effective thermal conductivity of fouling linear decreases with the increase of the porosity,and linear increases with the increase of the pore size.The analysis method brings convenience for design and cleaning of heat exchangers,at the same time,it opens up a new way for the further study of heat surface fouling in complex heat transfer process,make the calculation results are more accordant with practical circumstances.