A novel method for calculating effective thermal conductivity of particulate fouling

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 of particulate fouling is put forward by using IMAGE-PRO-PLUS image processing, the finite element method and ANSYS parametric design language. 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 ANSYS parametric design language. Secondly, effective thermal conductivity of particulate fouling model is calculated by the steady-state plate method. Then, the influence of particulate fouling micro-structure on effective thermal conductivity is explored. Last, it is also show that the calculation resulting of effective thermal conductivity agrees well with available experimental data and empirical correlation. Moreover, it has been shown that effective thermal conductivity 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 micro-structure on effective thermal conductivity of fouling, and provide the guidelines for designing of heat exchanger on calculating accurate thermal conductivity of fouling.