Characterization of the Exhaust Flow through the Diesel Oxidation Catalyst

• Author / Creator

  Symko, Giffin S

• The result of adding an insulation ring to the interior of the Diesel oxidation catalyst on pressure drop and light-off characteristics is investigated by injecting a ceramic material into the channels of the monolith forming a circular ring. The steady state pressure drop is recorded as a function of the mass flow rate while the transient temperature response is recorded as a function of time. The experimental results are compared with a numerical model created using ANSYS Fluent. The experimental results show no statistical difference in pressure drop with the addition of an insulation ring as the pulsations in the exhaust flow, created by the engine, results in uncertainty larger than the expected difference in pressure drop. The numerical model shows an increase in pressure drop that corresponds to the decrease in flow area which results in an increase in viscous resistance through the remaining channels of the monolith. The experimental results indicate that the addition of an insulation ring increases the heat capacity of the DOC requiring more energy and time to reach steady state. However, the numerical model indicates that the increase in time to reach steady state is due to the slow rate of heating of the insulation ring, while the rate of heating of the monolith is increased, with the exception of a small area directly adjacent to the insulation ring. The experimental results show no statistical difference in pressure drop while the numerical model indicates an increase in pressure drop with the addition of an insulation ring. The light-off characteristics of the DOC with the addition of an insulation ring may be improved as the rate of heating is increased across the monolith, with the exception of directly adjacent to the insulation ring. Whether the decrease in the rate of heating adjacent to the insulation ring offsets the benefits of the increase for the remainder of the monolith needs to be further explored.

• Subjects / Keywords

  • Diesel Oxidation Catalyst
  • Light-Off
  • Viscous Resistance
  • Pressure Drop

• Graduation date

  Spring 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3H98ZV1X

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.