AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Drift Tube Ion Mobility Measurements of Sub-10 nm Soot Particles Produced in Flames
DAVID BUCKLEY, Christopher Hogan Jr., University of Minnesota
Abstract Number: 77 Working Group: Combustion
Abstract The sampling of soot nanoparticles formed in flames is often challenging, as without proper dilution particles grow in sampling lines via coagulation, and because most combustion systems produce a time varying aerosol. In this study, we apply a novel drift tube ion mobility spectrometer coupled with a condensation particle counter (DTIMS-CPC) to measure the size distributions of sub 10 nm soot particles formed in a non-premixed methane flame. Unlike differential mobility analyzers (DMAs), a DTIMS samples particles all derived from an identical sample location and at a specific time, hence DTIMS-CPC measurements enable direct examination of temporal variation in soot formation. In addition to size distribution measurements, we apply tandem mobility analysis with a DMA-DTIMS-CPC system to examine to extent of vapor (water, aromatic compounds, and alkanes) uptake by soot particles, and infer vapor binding coefficients as a function of particle size. This work shows the DTIMS-CPC measurement is a viable alternative to DMA measurement for combustion generated nanoparticles, and that DTIMS measurements have advantages over DMAs in examination temporal variation in size distributions.