Modeling deposition of particles in vertical square ventilation duct flows

Release time:2024-08-09  Hits:

• Affiliation of Author(s):建筑设备科学与工程学院
• Journal:Building and Environment
• Key Words:中文关键字：粒子；通风管道；计算流体力学；拉格朗日涡旋生存期模型；无因次粒子沉积速度；雷诺-时均纳维斯托克方程，英文关键字：Particles；Ventilation ducts；Computational fluid dy
• Abstract:The presence, flow, and distribution of particle in heating, ventilation, and air-conditioning (HVAC) ducts influence the quality of air in buildings and hence the health of building occupants. To shed a better light on the flow of particles in HVAC ducts this a paper has considered the effects of drag, lift force, gravity, Brownian diffusion, and turbulent diffusion on the dimensionless deposition velocity of particles in smooth vertical ventilation ducts using fully developed and developing velocity profiles. Based on the Reynolds stress transport model (RSM) at two different air velocities, 3.0 m/s and 7.0 m/s, the aforementioned effects were predicted using Reynolds-averaged NaviereStokes (RANS)eLagrangian simulation on square shaped ducts under vertical flows. Preliminary results suggest that the gravity of particles does not directly change the dimensionless deposition velocity in vertical flows. Nevertheless, the gravity of particles contributes to changing the Saffman lift force. It is thus the Saffman lift force that directly changes the dimensionless deposition velocity of particles in vertical flows. In addition, the difference in the dimensionless deposition velocities between fully developed and developing flows is owing to the turbulent diffusion, turbulent intensity, and needless to say, the Saffman lift force under different dimensionless particle relaxation time.
• Note:李安桂
• First Author:李安桂[重名-待确认],gaoran
• Indexed by:Journal paper
• Volume:卷：46
• Issue:期：1
• Page Number:页：245-252
• Translation or Not:no
• Date of Publication:2011-04-01