Effects of Downwash when Measuring Gas Concentration with UAV-Mounted Gas Sensors

<p>"This research concludes that the downwash region of a rotary-wing unmanned aerial vehicle (UAV) does not produce pressure variations substantial enough to cause significant changes in density-based gas concentration measurements. US regulations evaluate gas concentration as a function of gas density, and accurate concentration measurements are critical for protecting health and safety, which means evaluation of actual downwash effects on measured gas concentration is essential.</p> <p>During experimentation, the UAV was fixed to a stand in a sealed chamber filled with NOx (NO and NO₂) of constant concentration. The UAV rotors ran at hovering speeds, and gas concentrations were measured at various locations around the UAV. NOx was chosen due to intended US regulations on surface mine blasting NOx emissions, though the results should be applicable to most emissions of interest that are monitored by a UAV system. All variables other than the presence of downwash were held constant or accounted for, so the only source of concentration variation would have been caused by pressure changes in the downwash region. No significant variations were observed, providing evidence that downwash pressure variations are not substantial enough to alter density-based gas concentration measurements.</p> <p>Numerous researchers have suggested that downwash may affect gas concentration measurements, though no researcher has previously isolated and defined the effect. This dissertation’s findings allow researchers to safely assume this source of previously undefined error is statistically negligible, provided the UAV and gas sampling point are located entirely within the gas cloud and the downwash region has stabilized"--Abstract, p. iii</p>

Name thesis:degree_name

Ph. D. in Explosives Engineering

Grantor

Missouri University of Science and Technology

Author dc:creator

• Brinkman, Jacob Lane

• blasting
• downwash
• gas emissions
• gas monitor
• UAV
• Engineering
• Explosives Engineering
• Mining Engineering

Repository record dc:identifier

https://scholarsmine.mst.edu/doctoral_dissertations/3254

OAI identifier oai:identifier

oai:scholarsmine.mst.edu:doctoral_dissertations-4259