2026-09-22T03:33:50Zhttps://bura.brunel.ac.uk/oai/request

oai:bura.brunel.ac.uk:2438/66182014-11-01T13:05:38Zcom_2438_23com_2438_58com_2438_8627com_2438_8620col_2438_3672col_2438_8629col_2438_235

Lawrie, JB Warren, Daniel 2012-09-12T14:05:28Z 2012-09-12T14:05:28Z 1999 http://bura.brunel.ac.uk/handle/2438/6618 This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Eigen-mode matching techniques offer a versatile approach for solving acoustic scattering problems in ducts. However, until recently, these techniques have been restricted to problems in which the boundary conditions contain at most one derivative, that is, Neumann, Dirichlet or Robin's conditions. Here a method is developed to solve scattering problems in ducts that are discontinuous in height and have at least one surface described by a high order boundary condition. Attention is focussed on the membrane condition, but the method can be extended to elastic plates and other higher order conditions. An original orthogonality condition is derived and used to solve two problems. Limiting cases of the results are compared with some special cases solveable by standard Fourier techniques and (for the case of no height discontinuity) the Wiener-Hopf technique. Submitted by Lesh Gowreesunker (lesh.gowreesunker@brunel.ac.uk) on 2012-09-12T14:05:12Z No. of bitstreams: 1 Fulltext.pdf: 5971084 bytes, checksum: cadb4f4ade679cf5f4c8edd4f3a88f23 (MD5) Approved for entry into archive by Lesh Gowreesunker(lesh.gowreesunker@brunel.ac.uk) on 2012-09-12T14:05:28Z (GMT) No. of bitstreams: 1 Fulltext.pdf: 5971084 bytes, checksum: cadb4f4ade679cf5f4c8edd4f3a88f23 (MD5) Made available in DSpace on 2012-09-12T14:05:28Z (GMT). No. of bitstreams: 1 Fulltext.pdf: 5971084 bytes, checksum: cadb4f4ade679cf5f4c8edd4f3a88f23 (MD5) This study is funded by the Brunel University Department of Mathematical Sciences en Brunel University, School of Information Systems, Computing and Mathematics School of Information Systems, Computing and Mathematics http://bura.brunel.ac.uk/bitstream/2438/6618/1/FulltextThesis.pdf The scattering of sound waves in two-dimensional ducts with discontinuities in height and material property Thesis