Research on the transport and deposition of nanoparticles in a rotating curved pipe

Abstract

A finite-volume code and the SIMPLE scheme are used to study the transport and deposition of nanoparticles in a rotating curved pipe for different angular velocities, Dean numbers, and Schmidt numbers. The results show that when the Schmidt number is small, the nanoparticle distributions are mostly determined by the axial velocity. When the Schmidt number is many orders of magnitude larger than 1, the secondary flow will dominate the nanoparticle distribution. When the pipe corotates, the distribution of nanoparticle mass fraction is similar to that for the stationary case. There is a "hot spot" deposition region near the outside edge of bend. When the pipe counter-rotates, the Coriolis force pushes the region with high value of nanoparticle mass fraction toward inside edge of the bend. The hot spot deposition region appears inside the edge. The particle deposition over the whole edge of the bend becomes uniform as the Dean number increases. The corotation of pipe makes the particle deposition efficiency a reduction, while high counter-rotation of pipe only slightly affects the deposition efficiency. When two kinds of secondary flows are coexisting, the relative deposition efficiency is larger than that for the stationary case.

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