Performance evaluation of the cost-effective and lightweight Alphasense optical particle counter for use onboard unmanned aerial vehicles

Performance evaluation of the cost-effective and lightweight Alphasense optical particle counter for use onboard unmanned aerial vehicles

Bezantakos, Spyros (Universite du Littoral Cote d'Opal)
Schmidt-Ott, F.F.A. (Universiteit Maastricht)
Biskos, G. (TU Delft Atmospheric Remote Sensing; The Cyprus Institute)

2017-12-22

Air quality monitoring using airborne platforms is rapidly gaining ground as unmanned aerial vehicles (UAVs) are becoming easier, less expensive, and safer to operate on a routine basis. To facilitate measurements of key atmospheric properties, however, efforts are still required in developing/testing miniaturized instruments for use onboard UAVs. Here, we test two commercially available cost-effective/lightweight optical particle counters (OPCs; Alphasense Model N2) capable of measuring the size distributions of airborne particles having diameters from 380 nm to 17 μm. Tests were made against a reference and recently calibrated OPC (Grimm Model 1.109) using monodisperse polystyrene spheres. All instruments were placed in a chamber in which the temperature and pressure varied in the ranges of –5 to 23°C and 0.7 to 1.0 atm, respectively; conditions typically encountered during UAV flights. Agreement in the particle number concentrations measured by the Alphasense and the Grimm OPCs was within 40%, under all experimental conditions used in this work, when particles having sizes >1 μm were employed during the tests. Deviations higher than 50%, however, were observed when the instruments were tested with 1.0- and 0.8-μm polysterene spheres. The particle sizes reported by both Alphasense OPCs were within ± 5% with respect to the nominal polysterene spheres’ size under all operating pressures and temperatures down to 5°C. At lower temperatures, the sizing accuracy of one of the two Alphasense OPCs degraded significantly. While our findings support that the Alphasense OPCs can be used at low temperature/pressure conditions, they should be carefully tested prior the measurements to ensure good performance.

http://resolver.tudelft.nl/uuid:b4da1749-7704-4497-b740-1af6256c29e7

https://doi.org/10.1080/02786826.2017.1412394

0278-6826

Aerosol Science and Technology, 52 (2018) (4), 385-392

Institutional Repository

journal article

© 2017 Spyros Bezantakos, F.F.A. Schmidt-Ott, G. Biskos