**ABSTRACT**

The accurate thermal conductivity of fouling plays a very significant role in designing heat exchanger. In this paper, a novel method of calculating the effective thermal conductivity (ETC) of particulate fouling is put forward by using Image-Pro-Plus image processing, the finite element method and ANSYS parametric design language (APDL). First of all, according to the analysis on the particulate fouling samples features, the particulate fouling is considered as porous media with fractal characteristics, whose microscopic network model is established using the finite element method, and each unit body material properties are randomly assigned by APDL. Secondly, ETC of particulate fouling model is calculated by the steady state plate method. And then, the influence of particulate fouling microstructure on ETC is explored. Last, it is also show that the calculation resulting of ETC agrees well with available experimental data and empirical correlation. Moreover, it has been shown that ETC of particulate fouling is closely associated with the porosity and pore size. The method can be used to research on the thermal conductivity of fouling, discuss the influence of microstructure on ETC of fouling, and provide the guidelines for designing of heat exchanger on calculating accurate thermal conductivity of fouling.

**KEYWORDS**

PAPER SUBMITTED: 2019-03-08

PAPER REVISED: 2019-06-05

PAPER ACCEPTED: 2019-06-29

PUBLISHED ONLINE: 2019-08-10

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