Horizontal Combinations

Combustion Kinetics Laboratory

Aerospace and Mechanical Engineering

Professor Hai Wang











Jeremy Cain, Graduate Student




My research focuses on heterogeneous chemical kinetics (i.e., reactions with gases and particles).  Preliminary investigations focused on designing a reactor using computational fluid dynamics to accomplish the following: remove concentration gradient dependencies on uptake, characterize reaction extent for individual particles, and mimic reactions as close to reality as possible with respect to reactant gas concentration and reaction time.  The end result was the Particle-on-Substrate Stagnation Flow Reactor (PS-SFR).  The reactor was proven to yield good results for reactions of two different particles, sea salt (NaCl) and calcium carbonate (CaCO3), with nitric acid (HNO3).  Attention was then turned to the heterogeneous kinetics of soot.  Before beginning to measure reaction rates, the soot particles must be characterized first; in particular, the surface chemistry must be known.  This was done by sampling particles generated on a flat flame burner, depositing them on substrates in a cascade impactor (nano-MOUDI) and using micro-FTIR spectroscopy (a microscope coupled to an IR spectrometer) to analyze the surface-bound chemical functional groups.  In particular, we have observed oxygenated groups (single and double bonded) and aliphatics.  We are currently seeking to understand the presence of aliphatics, as current soot models only include hydrogen bonded to carbon in aromatic form.  A possible consequence of having these non-aromatic groups present on the surface of soot is for the particle to become oxidized, which would increase its ability to act as a cloud condensation nuclei (CCN).