A new simple algorithm of analytical inversion is proposed for the determination of aerosol particle size spectrum from diffusion battery penetrations. It is simpler and more transparent than analytical approaches published previously. The idea of the analytical solution is based on the operation principle of diffusion battery, which separates particles by their diffusivity into several classes. The size spectrum of particles in each class is approximated by a single-mode distribution, and the total size distribution is the sum of spectra from these classes. For this purpose, simple analytical formulas are derived to calculate the mean diameter of particles in each class from the diffusion battery penetrations. The advantage of the analytical approach is that it gives a one-to-one correspondence between the penetrations and the resulting spectrum without the necessity of complex mathematical processing, in contrast to the traditionally used numerical methods of solution of the inverse problem. However, experimental errors from the fluctuations of aerosol concentration can make the measured penetrations incompatible with any spectrum. Therefore, a smoothing procedure is proposed, which transforms incompatible penetrations into compatible ones within corridor of experimental errors.
|Журнал||Measurement: Journal of the International Measurement Confederation|
|Состояние||Опубликовано - ноя 2020|