*4.1. Comparison with Other Aggregation Models*

Figure 3 shows the comparison between the effective conductivity of aggregates containing polydispersed particles, as extracted with the use of the method developed here, and the results of the DLA method. The volume fraction of particles is *f<sup>p</sup>* = 0.1 and the standard deviation of the particle size is *σ* = 0.5*r*0, where *r*<sup>0</sup> is the mean radius of the particles. The aggregates consist of *N* = 42 particles and the thermal conductivity of the particles is considered *kr p* = *kp k f* larger than that that of the base fluid by a factor of 100. The simulation points are the averages of 10 realizations with the same morphological characteristics. In an earlier work by the authors, it was indicated that the mechanism of aggregation does not affect the effective conductivity for monodispersed particles. The same conclusion is drawn here for the case of polydispersed particles. However, the morphological characteristics of the aggregates appear to be significant for the effective thermal conductivity. Similar to the behaviour of aggregates of monodispersed particles, the thermal conductivity decreases with an increase in the fractal dimension.
