A Numerical Investigation of Frost Growth on Cold Surfaces Based on the Lattice Boltzmann Method

Jianying Gong,Guojun Li,Jinjuan Sun,Jianqiang Hou,Tieyu Gao

doi:10.3390/en11082077

Abstract

A numerical investigation of frost growth on a cold flat surface was presented based on two-dimensional Lattice Boltzmann model. This model has been validated to have less prediction error by past experiments. According to the results, it is shown that average frost density appears different at an increasing rate at different frosting stages. In addition, cold surface temperature has great influence on frost growth parameters such as frost crystal deposition mass, frost deposition rate, and frost crystal volume fraction. It was found that the frost crystal deposition mass, frost crystal volume, and the deposition rate first increase rapidly, then gradually slow down, finally remaining unchanged while the cold surface temperature decreases. The further away from the cold surface, the more sparser the frost layer structure becomes due to the smaller frost crystal volume fraction.

Highlights

Heat exchangers will be subjected to deposition and progressive growth of frost, when humid air flows through the heat exchangers’ surface where the temperature is less than both zero degrees centigrade and the ambient air dew point temperature
This study presents a two-dimensional LB model to simulate the frost growth on a cold flat surface based on the fractal theory (DLA model)
This paper presented a two-dimensional LB model to simulate frosting process on a cold surface based on the fractal theory (DLA model)

Summary

Introduction

Heat exchangers will be subjected to deposition and progressive growth of frost, when humid air flows through the heat exchangers’ surface where the temperature is less than both zero degrees centigrade and the ambient air dew point temperature. To guarantee normal operation of the heat exchanger, a frosting investigation on a cold surface is necessary. In 1984, a molecules diffusion model was proposed by O’Neal et al [4] In their model, the frost layer was regarded as a porous media and the mass transfer in the frost formation process increases frost thickness and increases frost density simultaneously. The frost layer was regarded as a porous media and the mass transfer in the frost formation process increases frost thickness and increases frost density simultaneously Later, this model was continually simplified and improved by researchers [5,6,7]

Methods

Results

Conclusion