@PhDThesis{	  itlic:2006-009,
  author	= {Eddie Wadbro},
  title		= {Topology Optimization for Acoustic Wave Propagation
		  Problems},
  school	= {Department of Information Technology, Uppsala University},
  department	= {Division of Scientific Computing},
  year		= {2006},
  number	= {2006-009},
  type		= {Licentiate thesis},
  month		= oct,
  day		= {13},
  copies-printed= {80},
  pages		= {112},
  abstract	= {The aim of this study is to develop numerical techniques
		  for the analysis and optimization of acoustic horns for
		  time harmonic wave propagation. An acoustic horn may be
		  viewed as an impedance transformer, designed to give an
		  impedance matching between the feeding waveguide and the
		  surrounding air. When modifying the shape of the horn, the
		  quality of this impedance matching changes, as well as the
		  angular distribution of the radiated wave in the far field
		  (the directivity). The dimensions of the horns considered
		  are in the order of the wavelength. In this wavelength
		  region the wave physics is complicated, and it is hard to
		  apply elementary physical reasoning to enhance the
		  performance of the horn. Here, topology optimization is
		  applied to improve the efficiency and to gain control over
		  the directivity of the acoustic horn.}
}