Modeling of contaminant particle deposition and rebound in a vertical duct

Particle - wall collision should be important in the simulation of particle deposition. In this paper, contaminant particle deposition and rebound or resuspension in a vertical duct are investigated by employing an algebraic rigid particle wall impact model. Eight particle size groups (0.01, 0.1, 0.5, 1, 5, 10, 60 and 100μm) ranging from 0.01 to 100μm are investigated. Detailed characteristic physical properties and phenomena of particle movement and impact are simulated and analyzed. A comparison between the current particle wall model and conventional trapped model shows that particle wall model is an important factor to affect the particle fate in ventilation duct, especially for larger particles. The deposition behavior exhibits a reverse phenomenon from smaller ones when the inlet velocity changes from low to high. Particle capture fraction vary differently with particle diameter and inlet velocity. Due to the algebraic expression of the particle wall impact model, it is efficient and robust for engineering application, such as HVAC duct.