Many scenarios exist that involve vibrating structures radiating sound into an interior field, including interior aircraft noise, noise in the cabins of automobiles and other vehicles, and transmission between two adjoining rooms. The proposed research focuses on developing three active noise control approaches for minimizing the sound field created by vibrating structures radiating into enclosed sound fields. The three approaches consist of: i) minimizing the acoustic energy density at discrete locations in the acoustic field, ii) minimizing the structural energy density at discrete locations on the vibrating structure, and iii) minimizing the structural power flow at discrete locations on the vibrating structure. The effectiveness of each approach for minimizing the interior acoustic field will be compared and contrasted. Relationships and correlations between the three measured quantities in the control approaches will be developed. A greater understanding of the coupling that exists between the acoustic energy (in the enclosed field) and the structural energy (in the vibrating structure) will also be acquired. This project will advance scientific knowledge through the discovery of new energy-based relationships, control techniques, and measurement techniques. This research has potential for significant societal benefits by enhancing noise control techniques in applications ranging from room acoustics, to an aircraft fuselage, to vehicle cabs. Through this research, future professionals will be trained with strong research skills and broad backgrounds in acoustics and structural dynamics. These two disciplines are often considered separately but this project will couple them in approaching new and innovative ideas. Graduate and undergraduate students will be involved on teams, and will learn to effectively interact with one another. The teams will be supported and encouraged to publish and present their research at technical meetings. A relatively large number of female students have participated in the research group. The PIs will continue to encourage additional female and minority students to become involved. The objective is to continue to teach those involved with the group the importance and strength of having a broad and diverse research group. Numerous K-12 groups visit our facilities each year, and will see and be exposed to this work as a highlight of the research at BYU.
