A 2-D Diesel Particulate Filter Regeneration Model

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A 2-D Diesel Particulate Filter Regeneration
Model
Yu Zhang
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Introduction

• Diesel particulate filter (DPF) collects diesel
  particulate (mainly soot) emissions.
• A soot layer is formed over a porous wall and
  removed by combustion
• (This soot layer removing process is
  referred as regeneration)
• A 2-D time-dependent model for the cross-section
  of a filter channel is formed to get a better
  understanding of the DPF regeneration process

symmetry
Inlet channel
Soot layer
Porous wall
outlet channel
symmetry
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Governing Equations

• Momentum Balances
• Navier-Stokes equation
• ( in open channel)
• Brinkman equation
• (soot layer and porous wall)

• Mass Balance
• Maxwell-Stefan diffusion and convection
• Energy Balance

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Governing Equations

• Chemical reactions
• Reaction rate
• Heat source

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Model Formulation
Plug
Plug
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Solution

• T distribution at 200s and 500s

• P distribution at 0s and 500s

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Solution

• Soot layer thickness distribution

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Validation

• Exhaust back pressure comparison

• Soot layer thickness distribution without
  considering chemical reactions

Literature
Calculated
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Parametric Study
T350K
T400K
T420K
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Conclusion

• Soot layer thickness distribution is non-uniform
  due to the non-uniform temperature distribution
  along the filter channel
• Soot layer thickness is sensitive to the exhaust
  temperature. As exhaust temperature increases,
  the soot layer thickness decreases significantly