Development of a Compact Instrumentation Package for Characterization of Aerosols, Turbulence and Surface Characteristics in the Arctic from Unmanned Aerial Vehicles

This Small Business Innovation Research Phase I project will support the development of a new, compact instrumentation package for unmanned aerial vehicles (UAVs). The package will include modules to measure aerosol size distributions, cloud condensation nucleus (CCN) concentrations, ambient turbulence and to acquire digital images during UAV flights. The instrument suite will be designed with a single, integrated control system so that any desired combination of instruments might be deployed. A coupled electrical-mobility, aerodynamic and light-scattering-based aerosol number size distribution measurement system will be developed capable of rapid airborne observations over the 0.01 to 10 micrometer diameter range. A turbulent-mixing-based condensation particle counter that has already operated on-board UAVs will serve as the detector for the new mobility-based sizer. A prototype of the mobility classifier will be fabricated and tested against conventional scanning differential mobility sizing systems using NIST traceable calibration particles. A novel light-scattering and Stokes-number-based sizing system will be designed, modeled and prototyped to simultaneously measure multiple particle properties for diameters larger than a few tenths of a micrometer. The large particle sizer development will focus on reducing the sizing uncertainties associated with methods based on light-scattering alone that suffer from multi-valued Mie scattering response. A miniaturized Cloud Condensation Nucleus (CCN) counter design will be developed and optimized using Computational Fluid Dynamics (CFD) modeling. For atmospheric turbulence measurements, gust probe, hot film, and sonic anemometer- based technologies will explored to determine which can be most effectively miniaturized and repackaged to fit the UAV payload. The various techniques will be evaluated with respect to sensitivity to platform attitude and motion. During the Phase II project, a prototype of the miniaturized turbulence system will be built and intercompared with commercially available hot film anemometers deployed within BMIs wind tunnel facility. Imaging technology will be integrated into the microprocessor-based control electronics to allow characterization of land and ocean surfaces during UAV flights. The overall development project will build upon BMIs existing UAV instrument suite development, in particular the deployment of aerosol instruments (particle counter, light absorption and filter-based chemical composition measurements) on- board a Manta UAV over the Arctic during the spring of 2011. The new technology will help mitigate current measurement limitations in applications that include aerosol health effects studies, flux measurements of aerosol species from ocean and land surfaces, studies of rapid aerosol evolution in power-plant plumes, creation of data sets for climate change and urban air shed air quality models, drug development by pharmaceutical firms, and indoor air quality monitoring for green buildings, industry and households.