Inversion to obtain aerosol size distributions from measurements with a differential mobility analyzer

摘要: Abstract To measure size distributions of submicrometer aerosols with an electrical differential mobility analyzer (DMA) requires inversion procedure. The Knutson (1976) and the Hoppel (1978) procedures were numerically investigated for case log-normal aerosol distributions. It was found that procedure converges to same result as given by computational range geometric mean diameter ( χ g) 0.025-0.25 μm, standard deviation (σg) 1.1–2.4. error be greater than 10% in certain “forbidden zones” g σg values. For ideal DMA having no lower limit, only one forbidden zone exists, this consisting small boundary intercepts boundaries at = 1.25, 0.025 μ m 1.62, 0.25 . These results also apply actual when distribution particles larger singly charged limit is available a priori. If such information not available, concentration these assumed zero performing inversion. This assumption adds second zone, large values 2.44, 1.50, first remains nearly same.