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PSS Dynamics Model

Introduction

The current theory about the plate settlers predicts the failure for a certain sedimentation tank and plate spacing based on a failure mechanism called floc rollup. The floc roll up theory states that a floc hitting the bottom plate will experience a fluid velocity at its edge and a settling velocity. If the fluid velocity is higher than the settling velocity, then the floc will roll up the plate and will exit the plant without being captured.

This theory is based on the following assumptions:

  • The velocity profile at the edge of the particle is linearized,
  • Flocs are following straight lines,
  • Flocs are spheres,
  • There are no floc breakup or collision,
  • The presence of flocs do not affect the velocity profile,
  • The entrance region of a plate settler (where the velocity profile is not fully-developed) is ignored.

The current theory predicts failure by mean of a dimensionnless ratio: the ∏_V
Our firsts experimental results showed that the

Comments about how the code works

Attachments

trajectory9.m ||The main file. Contains the input parameters as well as the velocity-Verlet algorithm

Vfluid.m || Function that computes the velocity profile as a function of the distance inside a tube or plate settler

Re.m || Function that computes the Reynolds number (required for modeling the entrance region)

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