Over the past five years, significant progress has been made in the field of urban air mobility (e.g. Uber) and air parcel delivery (e.g. Amazon). Among the challenges that must be overcome before these aerial vehicles can be deployed in our cities, their noise emissions and their impact on public opinion will have to be addressed.

A leader in vertical take-off technology, Bell Textron Canada Ltd. and its innovation team based in Mirabel, QC, are actively pursuing noise mitigation strategies for aircraft propulsion systems. The objective of the project carried out with Optis and its partners was to study the acoustic signature of a shrouded fan under specific operating conditions and to evaluate noise reduction strategies.

This project, partly funded by the SAGE program, was achieved in partnership with Université de Sherbrooke and the Quebec company Mecanum:

Optis’ specific tasks in this project were as follows:

• Project management;
• Numerical prediction of ducted fan performance in various phases of flight using CFD;
• Evaluate tonal and broadband noise signature using OptiSound™;
• Compare numerical noise predictions with experimental data obtained in Université de Sherbrooke’s anechoic chamber;
• Perform sensitivity study of ducted fan noise with respect to design features and operating parameters;
• Provide recommendations on most beneficial noise mitigation strategies.

This project, funded in part by the SAGE program, was carried out in collaboration with the Université de Sherbrooke and the Quebec company Mecanum.