Development and Testing of the Universal Aerosol Conditioner

• Author / Creator

  Chen, Kerry

• A general-purpose aerosol conditioning device called the Universal Aerosol Conditioner has been designed and tested. The device can condition the aerosol in multiple ways. It can dilute the aerosol with particle-free air, dilute only the gas-phase component of the aerosol without diluting the particle concentration, dilute all components of the aerosol, or denude the aerosol by removing material from the particle phase. The UAC can also humidify or dehumidify an aerosol by either using vapour or dry air respectively. The UAC accomplishes these processes by bringing the aerosol into contact with sheath air and allowing enough time for the gas-phase of the aerosol to diffuse into the sheath flow. Both flows are kept in the laminar regime and are controlled. A theoretical model was derived to assess the theoretical performance of the UAC and was numerically solved. From the model it was determined that two parameters dictated the rate of diffusion between the two flows: the Péclet number and the ratio of sheath-to-aerosol flow rate. A prototype was designed, built, and experimentally validated. The prototype was used to measure the particle penetration efficiency and the gas dilution factor at various particle sizes and flow conditions. The results showed that at low aerosol and sheath flow combinations, the prototype behaved closely to the theoretical model but diverged from the theory once the sheath flows were increased due to mixing between the two flows.

• Subjects / Keywords

  • peclet
  • diffusion
  • particles
  • conditioning
  • numerical solution
  • penetration
  • dilution
  • aerosol

• Graduation date

  Spring 2019

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-s1f5-sy68

• License

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