A two dimensional finite element model is proposed to predict the effective thermal conductivity of rock sample. The heterogeneity of rock is taking into account in the numerical model at mesoscopic level by employ the statistical method. Finite element models simulated a steadystate thermal conductivity measurement device performing measurements on numerical samples with varying heterogeneity. The results obtained by numerical model agree well with that of theoretical serial and parallel model, and seems more accurate to predict effective thermal conductivity of the disordered structure. The simulations of different heterogeneity samples show the relationship between effective thermal conductivity and heterogeneity. For specimens with same geometry and heterogeneity, although the distribution of thermal parameters in each sample are different because of random distribution, numerical results show that they are almost the same effective thermal conductivity. The results also indicate that different heterogeneity of the specimen will get different effective thermal conductivity, more homogeneous of the sample, smaller difference with the input thermal conductivity. The heat flux vector of relatively heterogeneous sample is more disordered than that of homogeneous one. It deems that the microfractures in rock have the resistance effect on heat conduction. All of the results reveal that the proposed numerical model efficiently predicting the effective thermal conductivity of the heterogeneity rock.
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