Jha, SunilTidbury, G. H.Richards, T. L.2009-10-292009-10-291982-04http://hdl.handle.net/1826/3899The nature of sound in cars is discussed in the light of previous experimental and theoretical work, and the major contributions to interior noise are identified. The acoustic field inside a vibrating structure is analysed theoretically in terms of the acoustic cavity modes and the structural modes, and it is shown that'reduction of structural-acoustic coupling could reduce the response for a wide variety of force inputs. Finite element analyses of prismatic acoustic cavities and two-dimensinal ring structures are described and these are combined in a simple theoretical model of ring-mode excitation of sound. By stiffening selected structural elements, the structural-acoustic coupling, and hence the acoustic response, are reduced.enThesis or dissertation