Articles | Volume 6, issue 11
Atmos. Meas. Tech., 6, 3271–3280, 2013
Atmos. Meas. Tech., 6, 3271–3280, 2013

Research article 28 Nov 2013

Research article | 28 Nov 2013

Characterization of an aerodynamic lens for transmitting particles greater than 1 micrometer in diameter into the Aerodyne aerosol mass spectrometer

L. R. Williams1, L. A. Gonzalez2, J. Peck1, D. Trimborn3, J. McInnis4, M. R. Farrar5, K. D. Moore6, J. T. Jayne1, W. A. Robinson1, D. K. Lewis1,7, T. B. Onasch1, M. R. Canagaratna1, A. Trimborn3, M. T. Timko1,8, G. Magoon1, R. Deng9, D. Tang10, E. de la Rosa Blanco1, A. S. H. Prévôt11, K. A. Smith12, and D. R. Worsnop1 L. R. Williams et al.
  • 1Aerodyne Research, Inc., Billerica, MA, USA
  • 2CoolChip Technologies, Boston, MA, USA
  • 3AeroMegt, Hilden, Germany
  • 4Department of Chemistry, Northwestern University, Evanston, IL, USA
  • 5Cambridge Rindge and Latin High School, Cambridge, MA, USA
  • 6Space Dynamics Laboratory, Utah State University Research Foundation, North Logan, UT, USA
  • 7Department of Chemistry, Connecticut College, New London, CT, USA
  • 8Department of Chemical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
  • 9Institute of Bioengineering and Nanotechnology, Singapore
  • 10Dynamic Engineering Inc., Houston, TX, USA
  • 11Paul Scherrer Institute, Villigen, Switzerland
  • 12Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA

Abstract. We have designed and characterized a new inlet and aerodynamic lens for the Aerodyne aerosol mass spectrometer (AMS) that transmits particles between 80 nm and more than 3 μm in vacuum aerodynamic diameter. The design of the inlet and lens was optimized with computational fluid dynamics (CFD) modeling of particle trajectories. Major changes include a redesigned critical orifice holder and valve assembly, addition of a relaxation chamber behind the critical orifice, and a higher lens operating pressure. The transmission efficiency of the new inlet and lens was characterized experimentally with size-selected particles. Experimental measurements are in good agreement with the calculated transmission efficiency.