Distribution characteristics of supersaturation in pipeline of gravity air dust removal system

The supersaturation level of gravity air dust removal system was explored to provide a basis for system optimization. Firstly, the gravity air dust removal system was simplified and physical and mathematical models were constructed. Secondly, Fluent user-defined scalar(UDS) was used to analyze water vapor phase. The variable heat and mass transfer models were calculated. The influence of factors such as pipe diameter, inlet air temperature, wall hot water temperature, inlet air humidity and hot water adding position on the distribution of supersaturation in the pipe during natural convection was studied. Finally, a three-factor three-level single-response test design was carried out using response surface analysis to determine the degree of influence of pipe diameter, hot water temperature and hot water addition position on supersaturation. The results show that as the pipe diameter increases, the average supersaturation increases firstly and then decreases. The average supersaturation increases with the increase of the temperature difference between air and hot water. The relative humidity of the inlet air has little effect on the degree of supersaturation. Compared with the full coverage of hot water, it is more beneficial to increase the supersaturation level of the pipeline when the hot water is added to the location close to the outlet of the pipeline. The hot water temperature has a much greater impact on the supersaturation than the diameter of the pipeline and the location of hot water. The diameter and the position where the hot water is added have the same effect on the supersaturation. When optimizing the system working condition parameters, the influence of hot water temperature can be emphatically considered and the pipe diameter and hot water adding position can be considered as secondary factors. © 2021, Central South University Press. All right reserved.