A numerical study of particle wall-deposition in a turbulent square duct flow

Particle deposition in turbulent square duct flows

“…In fact, for the largest St=6.43 particles, figure 2 (i), and at all times considered, deposition almost never happened close to the side walls. This finding is in line with that of Winkler et al (2006) who used LES of a duct flow at Re b =5,810 to investigate deposition at St=0. 072-256.32, noting preferential deposition at the wall centre with little in the duct corners.…”

“…For the Re b =10k flow, the largest particles preferentially deposit near the centre of the duct floor at all times, in contrast with the higher Reynolds number flows, and these particles are also never observed to deposit near the side walls. These findings are in line with those of Winkler et al (2006) and Phares and Sharma (2006).…”

“…Huser & Biringen 1993) and large eddy simulations (e.g. Winkler et al 2006). All these investigations have demonstrated that turbulence-driven secondary motions that arise in the plane of the duct cross-section act to transfer fluid momentum from the centre of the duct to its corners.…”

“…In contrast to the body of work on single-phase flows, there exist few studies of particle-laden turbulent flows in ducts. Winkler et al (2006) did, however, apply large eddy simulation (LES), coupled with Lagrangian particle tracking, to study particle deposition in a duct flow, focusing on particles with response times in the range St = 0.072-256.32. also used DNS to study secondary flow effects on particle transport in a duct flow, although the effects of gravity were neglected. Both of these works focused on low Reynolds number turbulent flows (Re τ = 360 and 300, respectively, based on the mean friction velocity and duct width).…”

Attachment Efficiency of Polydisperse Nanoparticles Wall-Deposition

“…Chein and Liao 15) numerically studied particle deposition with diameters of 3, 5, and 10 nm in a finite-length heated channel flow under both molecular diffusion and thermophoretic effects, it is found that, for a finite channel length, higher particle deposition can be obtained for the various inlet temperature and fixed wall temperature cases. Winkler et al 16) studied the deposition of dense solid particles in a downward, fully developed turbulent square duct flow, and it is observed that the deposition rates in a square duct are greater than those in a pipe flow, especially for the low Stokes number particles. Zamankhan et al 17) numerically studied the flow and nanoparticle transport and deposition in a realistic human nasal passage.…”