This paper investigated the particle deposition in ventilation ducts with convex or concave wall cavity. The results indicates that the models adopted in this paper can accurately predict the characteristics of the air flow and particle deposition. The addition of convex and concave wall cavity are both beneficial for enhancing the particle deposition. Compared with smooth duct, the particle deposition can be strengthened about 2 to 4 orders of magnitude by the addition of convex and concave wall cavity in the turbulent diffusion and eddy diffusion-impaction regimes, whereas in the inertia-moderated regime, it increases comparatively slowly because movements of the large diameter particles are dominated by the inertia force. Thus, adding convex or concave wall cavity to the ducts is more beneficial for enhancing the particle deposition of the particles at small diameters. In addition, the ventilation ducts particle deposition velocity increase in convex wall cavity ducts is relatively larger than in concave wall cavity ducts.
Building Energy ＆ Environment
numerical simulation, ventilation duct, particle, deposition velocity