Faculty of Engineering and Applied Science
INSTITUTE OF SOUND AND VIBRATION RESEARCH
BEng Acoustical Engineering
MEng Acoustical Engineering		 Year: 2002-03




Module Specification



Unit/Module Code: Module Title:
IS318 Analytical and Numerical Acoustics


1.Basic Information
 
Department responsible for the module ISVR
Programme BEng Acoustical Engineering
MEng Acoustical Engineering 
Timetable Semester 2
Session 2002-03
Credit Value 10 CAT points (= 100 hours) Level
Pre-requisites Acoustics 1 or Mathematical Methods of Acoustics
Co-requisites None
Module Lecturers Dr CJC Jones
Professor PA Nelson
Contact cjcj@isvr.soton.ac.uk
Formal Contact Hours Lectures and tutorials (4 h/wk) = 20 hours
+ invited industrial speaker = 2 hours
+ computer workshop sessions = 4 hours
Private Study Hours 24 hours assignments
up to 50 hours other (including own study time to complete computer laboratory tasks)
Coursework One assignment 
External Examiner Dr. T. Cox 
Last Approved  
Last Revision 1/9/2002 
Course Web Site  
 
 
2.Description
 
2.1Aims
 
  The aims of this module are to provide a general introduction to analytical and numerical techniques in acoustics.

2.2Objectives (teaching)
 

 
  • To introduce the student to the formal analytical basis for the solution of complex problems in acoustics.
  • To describe numerical techniques available for the solution of problems in acoustics when analytical methods provide no means of solution.
  • To give the student direct experience of the use of computer software which employs numerical methods for the solution of problems.
 
2.3Objectives (planned learning outcomes)
 
 Knowledge and understanding
Having successfully completed the module, you will be able to demonstrate knowledge and understanding of:
  • Basic source models in acoustics, including monopole, dipole and higher order mutlipole sources.
  • Inhomogeneous wave equations and methods for their solution, including Green's function techniques.
  • Integral equation formulations for describing acoustic fields.
  • The basic principles underlying analysis of the generation of sound by unsteady flow.
  • The acoustics of enclosed sound fields at low frequency, including analytical models based on the assumption of light damping.
  • Green's functions for sound propagation in ducts and wave guides.
  • A range of numerical modelling techniques for the solution of the acoustic wave equation based on Finite Element and Boundary Element analysis.
  • The use of these techniques through engineering software packages for applications in duct acoustics, in automotive and other fields.
  • The mathematics of Finite Element and Boundary Element methods which is critical to their correct use in practice.
  • The interpretation of the results of numerical models.
 
 Cognitive (thinking) skills
  Having successfully completed the module, you will be able to:
  • Read, understand and interpret the literature relating to analytical and numerical methods in acoustics.
  • Recognise and select appropriate techniques for the solution of analytical and numerical problems in acoustics.
 
 Practical, subject-specific skills
Having sucessfully completed the module, you will be able to:
  • Use ANSYS and SYSNOISE to solve problems in acoustics to carry out design calculations on simplified model systems.
 
 Key transferable skills
Having successfully completed the module, you will be better able to acquire a working knowledge of new software packages. 
 
2.4Teaching and Learning Activities
 
 Teaching methods include
 
3 lectures a week.

Computing laboratories using proprietary engineering software packages to solve acoustic problems. The typical lab class size is 20. Two lecturers assist the students to work through the exercises provided. Feedback is given by advice and assistance in the laboratory session.

Assistance is given during the computing laboratory sessions.

Students need to work in their own time to complete the laboratory work and are able to go to the lecturers for assistance. 

 
 Learning activities include
 
Working on a formal assignment which is based on an example given in the laboratory, reading a set paper in the literature and then using the software provided to replicate the results. The assignment includes some development of the formulation they have used. Example sheets are provided to students in order to practise their analytical skills and these are backed up with interactive tutorial sessions. Students are encouraged to read supporting texts and a booklist is provided. 
 
2.5Methods of Assessment (summative assessment)
 
 BEng Acoustical Engineering
      Assessment Methods Number % contribution to final mark Comment
      Assignments  1  50  Computer based 
      Exam  1  50  2 h 
 MEng Acoustical Engineering
      Assessment Methods Number % contribution to final mark Comment
      Assignments  1  50  Computer based 
      Exam  1  50  2 h 

 
2.6Feedback to students during module study (formative assessment)
 
  • Tutorial assistance to cover issues raised through example sheets.
  • Computing laboratories provide informal assessment through individual interaction.
  • Previous examination papers with model answers are made available.
     
    2.7Relationship between the teaching, learning and assessment methods
     
    The examination tests students' knowledge of the procedures, techniques and terminology of analytical approaches to acoustical problems. Students have a choice of question in the exam (3 out of 4).

    The assignment tests students' ability to (1) apply the knowledge of mathematical models to carry out numerical modelling; (2) to interpret the results of models.

     
    3.TOPICS COVERED
     
    Multipole Sources
  • The point monopole source
  • The point dipole source; vector dipole strength.
  • Longitudinal and lateral quadrupole sources.
  • Series expansion techniques. The Inhomogeneous Wave Equation and its Solution
  • Conservation equations with distributions of volume and force input.
  • The Green function. Principle of reciprocity.
  • Solution of the inhomogeneous Helmholtz equation.
  • The Kirchoff-Helmholtz integral equation.
  • Implications for the active control of sound and radiation from arbitrary vibrating bodies. Introduction to Aeroacoustics
  • Inhomogeneous wave equation with quadrupole source term; Lighthill's acoustic analogy.
  • Scaling laws for jet noise and flow/surface interaction noise. Enclosed Sound Fields
  • The Green function for a rigid walled enclosure.
  • Eigenfunctions and eigenvalues.
  • Solution to the inhomogeneous Helmholtz equation; Light damping assumption. Sound in Ducts
  • Duct modes.
  • Cut off frequency, phase speed.
  • Green function for an infinite hard walled duct. Introduction to Acoustic Finite Element Analysis
  • Variational formulation for the wave equation.
  • Finite Element discretization and method of computing for 2-dimensional problems.
  • Normal modes of irregular-shaped cavities with acoustically hard walls.
  • Cavities with one pair of parallel walls, axisymmetric cavities, cavities of general shape.
  • Application to practical cavities.
  • Use of commercial software. Analysis of Irregular-Shaped Cavities with Non-Rigid Walls
  • Effect of vibrating surfaces and absorbing materials.
  • Practical applications, including duct acoustics, acoustic radiation.
  • Use of commercial software. Introduction to Boundary Element Methods
  • Boundary Integral form of the reduced wave equation
  • Direct collocation method.
  • Application to cavity acoustics.
  • Application to acoustic radiation. Non-uniqueness problems.
  • Use of commercial software. Indirect Boundary Element Method
  • Formulation in terms of single and double layer potential distributions.
  • Non-uniqueness problems.
  • Applications.


    •  
    4.RESOURCES
     
     Core Texts
      AUTHORS TITLE/EDITION/DATE PUBLISHER UNI. LIB Class Mark E.J. Richards Library
    1.A D PierceAcoustics - An Introduction to its Physical Principles and Applications
    2nd Edition, 1989 (+ solutions)
    1st Edition, 1981

    0883186128

    McGraw-Hill
    0070499616




    QC225PIE
    6 loan


    1 ref

    2.P M Morse
    K U Inguard    		Theoretical Acoustics
    2nd Edition, 1986

    1st Edition, 1968
    Princeton UP 0691024014
    McGraw-Hill
    (no ISBN)


    QC223MOR
    3 loan


    1 ref
    2 loan
    3.P A Nelson
    S J Elliott    		Active Control of Sound,
    1992    		 Academic Press
    0125154259    		QC247NEL
    1 loan1 ref
    1 loan
    4.P Filippi (ed)Theoretical Acoustics and Numerical Techniques
    1st Edition, 1983    		 Springer-Verlag (New York)
    0387817867
    3211817867    		QC223FIL


    2 loan
    5.M L MunjalAcoustics of Ducts and Mufflers
    1st Edition, 1987    		 WIT Press (Southampton)
    1-85312-570-9    		QC233MUN

    1 loan


    1 ref

    6.T W Wu (ed)Boundary Element Acoustics Fundamentals and Computer Codes WIT Press (Southampton)
    1-85312-570-9    		1 loan 1 ref

      Secondary Texts
    None
     
     Other library support
     
    The ISVR's E J Richards Library houses a specialist collection relating to noise and vibration.

     
     
     Staff required
     
    As well as the two lecturers assigned to this course, there is an industrial invited lecturer and another member of academic staff who provides assistance with the computer laboratories. 
     
     Teaching space, layout and equipment required
     
    A lecture room with 30 seats is required for three hours a week. The room should be equpped with overhead projection facilities, and blackboard and/or whiteboard. The occasional use of a data projector is required. 
     
     Laboratory space required
     
    None 
     
     Computer requirements
     
    These are provided by the Department - see above 
     
     Software requirements
     
    ANSYS (via SUCS); SYSNOISE (from LMS via their maintenance contract). 
     
     Off-campus activities
     
    None 
     
     Part-time/distance learning students
     
    No special provision is made 
     
     Other
     
    A list of useful websites is provided