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

oleh: L. R. Williams, L. A. Gonzalez, J. Peck, D. Trimborn, J. McInnis, M. R. Farrar, K. D. Moore, J. T. Jayne, W. A. Robinson, D. K. Lewis, T. B. Onasch, M. R. Canagaratna, A. Trimborn, M. T. Timko, G. Magoon, R. Deng, D. Tang, E. de la Rosa Blanco, A. S. H. Prévôt, K. A. Smith, D. R. Worsnop

Format: Article
Diterbitkan: Copernicus Publications 2013-11-01

Deskripsi

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.