Brechtel, Fredrick J.

DOE OSTI2019

Aerosol ionizer

A system and method comprising an ion production chamber having an ultra-violet light source disposed towards said chamber, a coated quartz plate between the chamber and the UV source whose coating absorbs incident UV light and ejects electrons into the chamber through the photoelectric effect, a harvest gas disposed to flow through the chamber from an inlet to an outlet, and a jet operable to introduce a sample into the harvest gas flow. In some embodiments the system includes using helium as the harvest gas. Certain embodiments include introducing a sample perpendicular to the harvest gas flow and using multiple sample introduction jets to increase mixing efficiency. In some embodiments the harvest gas and particle sample jet are one and the same. The charge sample may be coupled to a MEMS-based electrometer.

Brechtel, Fredrick J.↗

DOE OSTI2019

Compact Cloud Condensation Nucleus Counter for Unmanned Aerial Systems (UAS) and Long-Term Monitoring Applications (Final Report)

Brechtel Manufacturing Incorporated (BMI) is developing a compact, modular suite of new aerosol measurement technologies optimized for use on Unmanned Aerial Vehicles (UAVs) and other applications where space, weight, power and cost are significant barriers to deployment. The project is focused on a cloud condensation nucleus counter that exposes sampled particles to a simulated cloud environment and counts how many of the particles grow to micron-sized droplets. The new development helps address the need for reduced uncertainties in climate model sensitivities to ambient aerosol properties by promoting the capability to perform aerosol measurements more often, in more locations, and at reduced cost. Applications of the new technology include long-term measurements of the aerosol effects on cloud radiation, microphysical and precipitation processes, weather prediction and modelling studies, and weather modification studies.

47 OTHER INSTRUMENTATION↗

DOE OSTI2018

Aerosol ionizer

A system and method comprising an ion production chamber having an ultra-violet light source disposed towards said chamber, a coated quartz plate between the chamber and the UV source whose coating absorbs incident UV light and ejects electrons into the chamber through the photoelectric effect, a harvest gas disposed to flow through the chamber from an inlet to an outlet, and a jet operable to introduce a sample into the harvest gas flow. In some embodiments the system includes using helium as the harvest gas. Certain embodiments include introducing a sample perpendicular to the harvest gas flow and using multiple sample introduction jets to increase mixing efficiency. In some embodiments the harvest gas and particle sample jet are one and the same. The charge sample may be coupled to a MEMS-based electrometer.

36 MATERIALS SCIENCE↗

DOE OSTI2017

Compact Nanoparticle Size Distribution Measurement System for Unmanned Aerial Systems (UAS)

Brechtel Manufacturing Incorporated (BMI) is developing a compact, nanoparticle sizer optimized for use on Unmanned Aerial Vehicles (UAVs) and other applications where space, weight, power and cost are significant barriers to deployment. The instrument will allow observations of size-resolved aerosol number concentration (0.005 < D p < 0.3 μm, D p is particle diameter). The new development helps address the need for reduced uncertainties in atmospheric radiative transfer and weather prediction model sensitivities to ambient aerosol properties by promoting the capability to perform aerosol measurements more often, in more locations, and at reduced cost. Applications of the new technology include vertical atmospheric profiling with UAVs, balloons and other mobile platforms to constrain weather forecast models, long-term air quality measurements, aerosol health effects studies, and routine monitoring of ambient aerosol properties in urban air sheds.

47 OTHER INSTRUMENTATION↗