Tom Eppes, associate professor of electrical
and computer engineering, Ivana Milanovic,
professor of mechanical engineering, and Mike
DePanfilo, graduate student in the College of Engineering,
Technology, and Architecture (CETA), presented a paper at the May
2012 Euro-American Conference sponsored by the International
Journal of Arts & Sciences (IJSA) 2012 in Provence,
France. The conference brings together international academics to
present research in the fields of social sciences, humanities,
education and technology.
The paper, "Resonance Modes in an Acoustic Guitar," describes the results of a finite element analysis of the eigen-modes of a Collings guitar, a well-known design developed and custom manufactured by Jim Collings. The paper describes a method to predict resonance patterns based on its physical shape and wood composition. Discrete modes, known as eigen-frequencies, denote where the amplitude responses of the acoustic chamber are the largest. Each mode represents a solution to an equation classically described as Helmholtz resonance. A 3-dimensional model was constructed using COMSOL Multiphysics for the geometry size/shape, a spruce soundboard and mahogany side/back walls. The analysis focuses on the lower end of the dynamic range from 200Hz to 1,000Hz in which surface deformation, both total and normal to the surface, are examined. In addition, node and anti-node structures in the area where the bridge attaches to the top plate are explored.