A web-based aerosol calculator for research and education

 

Author

Scot T. Martin — Harvard University

Category

Infrastructure & Outreach

Description

This poster introduces a web-based computational tool for the practical implementation in research and education of several popular examples of aerosol calculations. The user of the AerosolCalculator begins by discretizing a lognormal distribution into a group of size bins. The user selects particle chemistry among the possibilities of ammonium sulfate, sodium chloride, sulfuric acid, and polystyrene latex. The user can then view the distribution in number, surface, volume, or mass space with respect to volume-equivalent diameter. Alternatively, the user can view the distributions with respect to aerodynamic (e.g., to simulate an aerodynamic particle sizer) or vacuum-aerodynamic diameter (e.g., to simulate an aerosol mass spectrometer). The user can apply a Boltzmann charge distribution and then view distributions with respect to mobility diameter or particle electric mobility. The user can pass the particles through a differential mobility analyzer to filter for particles of selected mobility (including diffusing and nondiffusing transfer functions). The user can simulate CCN activation at a particular supersaturation. The user can choose to apply deliquescence, efflorescence, and hygroscopic growth (with Kelvin effect) to the size distributions. The particle size distributions at each stage of the simulation can be downloaded in Excel format. Online tutorials accompany the simulations. Careful records are kept of the data sources of the physical and chemical properties of the particles. At present, the AerosolCalculator is of research-quality value to scientists working on CCN activation and HTDMA hygroscopic growth.