Modeling ultrasonic transducer in homogeneous and non-homogeneous media using DPSM method

Persistent Link:
http://hdl.handle.net/10150/280583
Title:
Modeling ultrasonic transducer in homogeneous and non-homogeneous media using DPSM method
Author:
Alnuaimi, Nasser Abdullah
Issue Date:
2004
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Modeling ultrasonic transducers is an important aspect of research in nondestructive evaluation and testing. In most nondestructive evaluation applications, the ultrasonic transducers are traditionally modeled as: (1) point sources generating spherical wave fronts (2) line sources generating cylindrical wave fronts, or (3) planar surfaces generating plane wave fronts. In reality, the transducer front face has finite dimensions; it is neither point source nor planar source because the ultrasound that emits from a piezoelectric transducer does not originate from a point or an infinite plane, but instead originates from the finite surface of the piezoelectric element with flat or curved front face. Analytically modeling the fields radiated by ultrasonic transducers is a very difficult task because of the large number of possible transducer types, sizes and configurations that are used in practice. In this study, a semi analytical technique the Distributed Point Source Method (DPSM) is adapted to model ultrasonic transducers. The DPSM discretizes the transducer surface into a finite number of elemental surfaces. As a result, the complexity associated with the discretization of the three-dimensional problem geometry as done in the finite element technique is reduced. In the DPSM technique, the fundamental governing equations for elastic wave propagation in a fluid and in a solid are solved. For this reason, the DPSM technique is called a semi-analytical technique. In this research, computer codes for computing the ultrasonic field in a three dimensional inhomogeneous medium in front of a transducer of finite dimension have been written in MatLab. Two different cases are considered in this study, nonhomogeneous fluid and fluid-solid interface. Both normal and inclined incidence cases are investigated. This investigation shows that DPSM is an efficient technique for modeling ultrasonic transducers in nonhomogeneous media.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Engineering, Civil.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Civil Engineering and Engineering Mechanics
Degree Grantor:
University of Arizona
Advisor:
Kundu, Tribikram

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleModeling ultrasonic transducer in homogeneous and non-homogeneous media using DPSM methoden_US
dc.creatorAlnuaimi, Nasser Abdullahen_US
dc.contributor.authorAlnuaimi, Nasser Abdullahen_US
dc.date.issued2004en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractModeling ultrasonic transducers is an important aspect of research in nondestructive evaluation and testing. In most nondestructive evaluation applications, the ultrasonic transducers are traditionally modeled as: (1) point sources generating spherical wave fronts (2) line sources generating cylindrical wave fronts, or (3) planar surfaces generating plane wave fronts. In reality, the transducer front face has finite dimensions; it is neither point source nor planar source because the ultrasound that emits from a piezoelectric transducer does not originate from a point or an infinite plane, but instead originates from the finite surface of the piezoelectric element with flat or curved front face. Analytically modeling the fields radiated by ultrasonic transducers is a very difficult task because of the large number of possible transducer types, sizes and configurations that are used in practice. In this study, a semi analytical technique the Distributed Point Source Method (DPSM) is adapted to model ultrasonic transducers. The DPSM discretizes the transducer surface into a finite number of elemental surfaces. As a result, the complexity associated with the discretization of the three-dimensional problem geometry as done in the finite element technique is reduced. In the DPSM technique, the fundamental governing equations for elastic wave propagation in a fluid and in a solid are solved. For this reason, the DPSM technique is called a semi-analytical technique. In this research, computer codes for computing the ultrasonic field in a three dimensional inhomogeneous medium in front of a transducer of finite dimension have been written in MatLab. Two different cases are considered in this study, nonhomogeneous fluid and fluid-solid interface. Both normal and inclined incidence cases are investigated. This investigation shows that DPSM is an efficient technique for modeling ultrasonic transducers in nonhomogeneous media.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectEngineering, Civil.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineCivil Engineering and Engineering Mechanicsen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorKundu, Tribikramen_US
dc.identifier.proquest3145036en_US
dc.identifier.bibrecord.b47211039en_US
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