Investigating solid particle deposition and concentration distribution near ventilation bend walls with different materials

This paper investigates the microparticle deposition and distribution in 90° ventilation duct bends by employing the Eulerian approach with Reynolds stress turbulent model and a Lagrangian trajectory method with particle-wall model. Scanning Electron Microscope (SEM) method is used to image and analyze the particle accumulations on different locations of walls in ventilation ducts. Particle concentration distribution in ventilation duct bends with three different wall materials are analyzed and discussed numerically. It is found that the maximum particle number concentrations for surface of lowest capture velocity could be 1.72-8.97 times near the bend walls to the surface of the highest one, while the accumulation of particles on bend walls is much higher for the latter surface. The present study could contribute to the understanding and application of different wall materials on contaminant particle motion in ventilation ducts.