AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
A Miniature Ionic Wind Electrostatic Collector for Ultrafine Particles
RAVI SANKAR VADDI, Yifei Guan, Igor Novosselov, University of Washington
Abstract Number: 401 Working Group: Instrumentation and Methods
Abstract Exposure to ultrafine particulate matter can cause significant health issues. Conventional particle monitors and collectors require an external pump for the air flow and are usually heavy, power consuming and difficult to use. We demonstrate a high-efficiency electrostatic collector that uses a needle and tube ionizer to charge the particles and at the same time provides electro-hydrodynamic (EHD) flow for sample aspiration. The charged particles are directed towards the inner surface of the collecting electrode (tube collector) by the electric field between the grounded collecting electrode and the high voltage corona needle.The corona voltage is varied from 3kV-5kV, the collection efficiency of the device is greater than 70% for the range of 20-150 nm corona voltage >4kV. The computational fluid dynamics (CFD) model for EHD flow is used to gain insight into flow patterns and spatial distribution of ion concentrations. The CFD model couples the interactions between fluid mechanics and electrostatics. The model shows excellent agreement with flow sampling rate and flow profiles at the exit of the electrostatic collector. The collection substrate and well-defined collection region allow for analysis of the collected particulate matter using multiple analytical methods.