Hygroscopic Tandem Differential Mobility Analyzer (HTDMA)
Project in collaboration with Univ. Stockholm - closed (2013-2014)

The HTDMA measures the hygroscopicity (water uptake) of aerosols, and it is suitable for any application where information is required on how particles of a selected diameter grow when they are exposed to controlled conditions of relative humidity.

It consists of two Differential Mobility Analyzers sequentially assembled. The first one allows the selection of the size of the dry particle to characterize, and the second one measures the size distribution of the hydrated particle after it has passed through a humidified chamber.  The ratio between the wet and dry diameters is referred to as the particle's growth factor.

The custom-made HTDMA from the Stockholm University was set up in Chacaltaya during 2013 and 2014 for a short campaign, where it unfortunately did not work well due to issues related to the high-altitude.

HTDMA (custom-made at ACES, Univ. Stockholm)