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Accession Number ADA584662
Title Application of the T-Matrix Method to the Numerical Modeling of a Linear Active Sonar Array.
Publication Date Jun 2013
Media Count 139p
Personal Author E. Ozer
Abstract Classically, the T-matrix method is a procedure to exactly compute the multiple scattering of an incident wave from a cloud of objects, given knowledge of the free-field scattering properties of a single object for an arbitrary incident wave. For acoustic waves, Profs. Baker and Scandrett have extended the T-matrix method to the case in which the radiation sources are also the scatterers, that is, to the case of an array of active transducers. This thesis is the first successful practical demonstration of the T-matrix method applied to an active sonar array for which a finite-element model was employed to compute the scattering properties of a single transducer. For validation, a T-matrix model of a linear array of piezoelectric spherical thin- shell transducers was modeled, for which analytical approximate values of the T- matrix element values are known. Subsequently, a T-matrix model of a linear array of piezoelectric class V flextensional ring-shell transducers was modeled. Beam patterns of the linear array models computed with the T-matrix method are compared with those of an array of point sources, demonstrating that the T-matrix method produces more realistic beam patterns, especially for end fire arrays.
Keywords Finite element analysis
Linear arrays
Matrix theory
Numerical analysis
Sonar arrays

Source Agency Non Paid ADAS
NTIS Subject Category 72B - Algebra, Analysis, Geometry, & Mathematical Logic
Corporate Author Naval Postgraduate School, Monterey, CA.
Document Type Thesis
Title Note Master's thesis.
NTIS Issue Number 1403
Contract Number N/A

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