CFD simulations to improve the aerosol tangential inlet of a Differential Mobility Analyzer

Differential Mobility Analyzers (DMA) have been studied for decades to classify a wide range of particle sizes. Its correct behavior is determined by the resolution, influenced by Brownian diffusion losses, distortions in the electric and flow field. The design configuration, especially inlets and outlets, can be a reason of these effects, affecting the DMA reliability. One of these configurations is the tangential inlet for polydisperse aerosol, used in the Vienna-type DMA. The use of a tangential inlet reduces the residence time and favored the aerosol flow distribution in the classification chamber. However, in this configuration swirl effects of non-uniform particle behaviors had previously been observed.