Near-wall Motion of Inertial Particles in Turbulent Channel Flows

• Author / Creator

  Masoud Ebrahimian

• Erosive wear due to particle–wall collision is an important challenge for slurry pipelines and
  solving this challenge requires a detailed understanding of particle motion near the wall. The
  complex phenomenology of the near-wall motion of particles in turbulent flows and the lack
  of a comprehensive theoretical or numerical approach to characterize it, highlight the need
  for experimental studies in this field. The objective of this research is to advance the current
  understanding of the near-wall motion of particles in turbulent flows and to study the effect
  of Reynolds number (Re), particle shape, size, and concentration on their motion using
  experimental methods. The analysis started with the investigation of particle dynamics
  and wall-collision in turbulent flows using Lagrangian particle tracking (LPT) techniques.
  It was found that the viscous forces decelerate near-wall particles in the streamwise direction,
  while the near-wall lift forces pushed the particles away from the wall. The change of Re
  affected the mean acceleration of particles and their collision with the wall. The effect of Re
  on particles' acceleration reduced by increasing the distance from the wall. The analysis also
  showed the effect of particle size and shape on particles’ dynamics and their collision with
  the wall. In addition, investigations showed that increasing the concentration of particles
  reduced their kinetic energy and acceleration in the streamwise direction while it increased
  these two parameters in the wall-normal direction. Finally, the motion of particles in a
  drag-reduced polymer solution was investigated. The results demonstrated the potential of
  polymer additives in reducing erosive wear in slurry pipelines.

• Subjects / Keywords

  • Lagrangian particle tracking
  • Inertial particle motion in turbulent flow
  • Particle–wall collision
  • Turbulent multiphase flow

• Graduation date

  Spring 2020

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-ferc-1t84

• License

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