By Danielle Fretwell
The Francis College of Engineering, Department of Mechanical Engineering, invites you to attend a master’s thesis defense by John Yirrell on the “Development of a Passive Monitoring Technique for Localization of Anomalous Acoustic Sources on Operational Wind Turbine Blades.”
Candidate Name: John Yirrell
Defense Date: March 31, 2023
Time: 10 to 11:30 a.m.
Location: Ball Hall 302 – in person
This will be an in-person defense with a Zoom option. Those interested in attending virtually should contact the student (John_Yirrell@student.uml.edu) and the committee chair (Murat_Inalpolat@uml.edu) at least 24 hours prior to the defense to request access to the meeting.
- Advisor Murat Inalpolat, Ph.D., Associate Professor, Department of Mechanical Engineering, University of Massachusetts Lowell
- David Willis, Ph.D., Associate Professor, Department of Mechanical Engineering, University of Massachusetts Lowell
- Stephen Johnson, Ph.D., Adjunct Professor, Department of Mechanical Engineering, University of Massachusetts Lowell
Wind energy capacity has increased nearly tenfold in the United States over the last decade, driven by a transition to renewable energy and a reduction in costs for new wind projects. To reduce the need for inspections and unscheduled repairs of turbine blades, a passive, acoustics-based health monitoring system has been proposed which consists of a single, low-cost microphone placed near the base of the tower. This thesis proposes a methodology for the localization of anomalous acoustic features by measuring and interpreting frequency modulations in the acoustic signal as each blade passes above the microphone. To validate this approach, analytical, lab-scale, and full-scale studies were conducted. As a result of these experiments, the limitations and strengths of this approach are documented, and a general frequency modulation algorithm is described for any system geometry.
All interested students and faculty members are invited to attend the online defense via remote access.