A finite volume diffusion limited aggregation model for predicting the effective thermal conductivity of frost
Abstract The present work is aimed at advancing a computational model for predicting the thermal conductivity of frost formed under different working conditions and, therefore, spanning a wide range of frost morphologies. The frost growth was modeled by means of the fractal theory, particularly the diffusion limited aggregation approach which forms heterogeneous porous media that emulate the morphology of the frost layer. The density of the frosted medium was determined straightforwardly by the principle of mass conservation, whereas the effective thermal conductivity was calculated from the inverse solution of the heat diffusion problem using the finite volume method. It was found that the model predictions for the thermal conductivity were able to represent the experimental data obtained in house within the 15% thresholds. A sensitivity analysis of key operating conditions that affect the frost morphology is also reported.