Numerical simulation of droplets re-entrainment in baffle demister

Abstract

In this study, a Eulerian Wall Film (EWF) model and a discrete phase model (DPM) are applied to simulate the phenomenon of droplet re-entrainment in a baffle demister. The primary objective was to design a new hook plate and evaluate its influence on the performance. The results show that the phenomenon of droplet re-entrainment occurs owing to the separation and stripping of the liquid film at the corner of the demister. Moreover, the liquid film strips at the areas where the local velocity is quite high near the wall of the demister. With the installation of the hook, the removal efficiency increased from 68.4% to 87.2% at 3 m/s inlet velocity. When the inlet velocity was increased to 6 m/s, the removal efficiency reached 96.7%, indicating that the existence of the hook plate further improved the efficiency of the demister, whereas the pressure loss of the system also increased.

Keywords:

• Demister
• Eulerian Wall Film
• DPM
• droplet re-entrainment

Additional information

Funding

The authors gratefully acknowledge the financial support provided by the Key Research and Development Program of Zhejiang Province [No. 2019C03117].