NOISE, ACOUSTICS and VIBRO-ACOUSTICS
Possible uses for this information will include:
· Providing useful information to self-learners;
· Providing focus for the developers of short courses, text books and other learning material;
· Providing a basis for the production of self-test quizzes and examinations;
· Providing the basis for registers of suitably qualified and experienced persons.
Recommended Competences
CategoryCode Number / STATEMENT OF COMPETENCE / Standard
or
Advanced
and
EQF Level / Resource
Reference
Code
Pre-Requisites
NAVpr1 / Appropriate levels of Maths and Physics.
NAVpr2 / Statements of competence in category DV, FEA, CFD, MPHY and other relevant modules as appropriate to application and level.
Knowledge
When writing a statement of competence in this category, use the verbs .... state, sketch, list, define, or similar.
NAVkn1 / State the speed of sound in air and in sea water and state its general dependence on temperature. / S,6 / NAVref1
NAVkn2 / State the relationship between wavelength and frequency of sound waves in a fluid. / S,6 / NAVref2
NAVkn3 / Describe and explain the use of decibel measures in noise and vibration studies. / S,6 / NAVref3
NAVkn4 / Describe and explain the use of weighting scales such as dB(A) in noise studies. / S,6 / NAVref4
NAVkn5 / List typical noise levels that can be caused by various common sources. / S,6 / NAVref5
NAVkn6 / List the sources of noise relevant to your industry sector and highlight any characteristics. / S,6 / NAVref6
NAVkn7 / Describe the classical source-path-receiver concept in (vibro-)acoustics. / S,6 / NAVref7
NAVkn8 / State the frequency range of sounds typically heard by the human ear. / S,6 / NAVref8
NAVkn9 / State at what noise levels, over what time-spans, damage to human hearing can occur. Explain the term LAeq,T (or LEP,d) / A,7 / NAVref9
NAVkn10 / List the proximate sound absorption or impedance (or inverse: admittance) of various surfaces. / S,6 / NAVref10
NAVkn11 / Describe how the energy of sound waves can be dissipated in typical absorbent materials (surface treatments or bulk materials). / S,7 / NAVref11
NAVkn12 / State the basic governing equations or variational principles for noise and acoustic analyses. / A,7 / NAVref12
NAVkn13 / Explain when, how and why non-linearity may occur in acoustic phenomena. / A,7 / NAVref13
NAVkn14 / State the nodal degrees of freedom typically used in an acoustic analysis. / S,7 / NAVref14
NAVkn15 / Define the terms frequency domain analysis and time domain analysis in (vibro-)acoustics. / S,6 / NAVref15
Comprehension
When writing a statement of competence in this category, use the verbs .... describe, explain, classify, review or similar.
NAVco1 / Describe how sound radiation is typically produced by common mechanical/structural sources. / S,6 / NAVref16
NAVco2 / Explain the term directivity as applied to acoustic sources. / S,6 / NAVref17
NAVco3 / Explain the term radiation efficiency of an acoustic source. / S,7 / NAVref18
NAVco4 / Explain the terms bandwidth, broad-band, narrow-band and tonal (pure tone). / S,6 / NAVref19
NAVco5 / Describe how sound radiation is typically produced due to fluid flow. / A,7 / NAVref20
NAVco6 / Describe how structural vibration can be produced due to acoustic excitation. / S,7 / NAVref21
NAVco7 / Explain the phenomenon of coincidence frequency for sound incident on a transmitting panel. / A,7 / NAVref22
NAVco8 / Explain the phenomenon of acoustic fatigue. / A,7 / NAVref23
NAVco9 / Explain the phenomena of a turbulent boundary layer and random vibro-acoustics. / A,7 / NAVref24
NAVco10 / Describe how sound is typically propagated in a fluid. / S,6 / NAVref25
NAVco11 / Explain the terms sound power and sound intensity. / S,7 / NAVref26
NAVco12 / Explain the terms interference, reflection, scattering, diffraction and refraction in relation to acoustics. / S,6 / NAVref27
NAVco13 / Describe the effects of (mean) fluid flow on sound propagation in a fluid. / S,7 / NAVref28
NAVco14 / Explain what is implied by the term diffuse field in acoustics. / A,7 / NAVref29
NAVco15 / Explain the terms absorption, attenuation, impedance (or inverse: admittance) and anechoic (synonym ‘perfectly-matched layer’). / S,6 / NAVref30
NAVco16 / Describe how sound is absorbed in a typical acoustic treatment. / S,7 / NAVref31
NAVco17 / Explain the terms transmission loss and insertion loss. / A,7 / NAVref32
NAVco18 / Explain what is meant by panel contribution in the analysis of radiated sound power and/or sound pressure at a specified location. / A,7 / NAVref33
NAVco19 / Explain the principles and uses of a transfer path analysis in a vibro-acoustic analysis. / A,7 / NAVref34
NAVco20 / Explain the key features of the finite element method as applied to numerical simulations of acoustics. / S,7 / NAVref35
NAVco21 / Explain the key features of the boundary element method as applied to numerical simulations of acoustics. / S,7 / NAVref36
NAVco22 / Explain the terms interior, exterior, closed and open as applied to acoustic domains and their numerical simulation, with particular reference to the use of finite element and boundary element methods. / S,7 / NAVref37
NAVco23 / Describe how any issues relating to infinite boundaries (free field) can be handled in numerical simulations of acoustics. / S,7 / NAVref38
NAVco24 / Explain how absorbent boundaries and bulk absorbing materials can be included in finite element and boundary element models of acoustics. / A,7 / NAVref39
NAVco25 / Explain how any fluid-structure interaction can be handled in numerical simulations of acoustics. / A,7 / NAVref40
NAVco26 / Explain the issues of mesh density, upper frequency limit and sources of error and inaccuracy in finite element and boundary element modelling of acoustics; in BEM, explain irregular frequencies (or non-uniqueness). / S,7 / NAVref41
NAVco27 / Contrast the requirements for acoustic and structural discretizations in vibro-acoustic modelling. / A,7 / NAVref42
NAVco28 / Explain the key features of statistical energy analysis as it relates to numerical simulations of acoustics. Discuss its limitations and compare and contrast finite element and boundary element approaches. / A,7 / NAVref43
NAVco29 / Explain the key features of geometrical acoustics (ray/beam tracing and similar methods) as applied to numerical simulations of acoustics. Discuss its limitations and compare and contrast finite element and boundary element approaches. / A,7 / NAVref44
Application
When writing a statement of competence in this category, use the verbs .... employ, demonstrate, conduct, use, apply, solve, utilise or similar.
NAVap1 / Employ available software tools to carry out noise and acoustic studies. / S,6 / NAVref45
NAVap2 / Use pre-processing tools to prepare models for noise, acoustics and vibro-acoustic studies. Demonstrate understanding of the validation of model geometry by applying mesh-checking tools. Demonstrate understanding of the validation of boundary conditions and/or structure-acoustic coupling using graphical/tabular pre-processing tools. / S,6 / NAVref46
NAVap3 / Utilise post-processing facilities and graphics to convey results effectively. / S,7 / NAVref47
NAVap4 / Demonstrate understanding of how (vibro-)acoustic analysis software can be interfaced/integrated with other software for product design, structural analysis, multi-body dynamic analysis and/or fluid dynamics analysis. / S,7 / NAVref48
Analysis
When writing a statement of competence in this category, use the verbs .... analyse, calculate, determine, appraise or similar.
NAVan1 / Analyse the results from noise and acoustic studies and draw conclusions. / S,7 / NAVref49
NAVan2 / Determine whether the results from a noise and acoustic study are valid. / A,7 / NAVref50
NAVan3 / Calculate the effects of design changes on the results of a noise and (vibro-)acoustic study and analyse their benefits/optimality. / A,7 / NAVref51
Synthesis
When writing a statement of competence in this category, use the verbs .... construct, plan, formulate, prepare or similar.
NAVsy1 / Plan effective analysis strategies for noise and acoustic studies. / A,7 / NAVref52
NAVsy2 / Formulate a series of simple benchmarks in support of a noise and acoustic study related to your industry and applications. / A,7 / NAVref53
Evaluation
When writing a statement of competence in this category, use the verbs .... assess, justify, select, evaluate or similar.
NAVev1 / Provide effective specialist advice on noise and acoustics simulation to colleagues. / A,7 / NAVref54
NAVev2 / Assess appropriate hardware and software solutions to meet the needs of planned noise and acoustic studies. / A,7 / NAVref55
NAVev3 / Select suitable idealisations for noise and acoustic studies. / A,7 / NAVref56
NAVev4 / Justify the appropriateness of model boundaries in noise and acoustics studies. / A,7 / NAVref57
NAVev5 / Justify the appropriateness of acoustic source models in noise and acoustics studies. / A,7 / NAVref58
NAVev6 / Assess whether structural / acoustic coupling is significant in any simulation. / A,7 / NAVref59
REFERENCES:
Remarks: (1) The primary reference given is Handbook of Noise and Vibration Control, Crocker, Malcolm J (ed), John Wiley & Sons, 2007, ISBN 978-0-471-39599-7 (electronic ISBN 978-1-61583-474-7). For brevity, this is shortened to Handbook of N&V in what follows, without the full reference.
(2) The Handbook of N&V and another reference, Harris’ Shock and Vibration Handbook, are large, encyclopaedic volumes, but as well as paper copies they are also available as online e-books, in the ‘Knovel’ and ‘books24x7’ systems respectively, which may be accessible through university or other library services and also through subscription services such as the Institution of Mechanical Engineers (UK) ‘members virtual library’. The page references for Handbook of Noise & Vibration relate to both paper and online versions, since the online version is a series of PDF images of the paper version.
NAVref1 Handbook of N&V, Chapter 2, p.20
How To Get Started in Acoustics Analysis, Section 5, p.25, Tyrell, R J, NAFEMS, 1998
NAVref2 Handbook of N&V, Chapter 2, p.21
NAVref3 Handbook of N&V, Chapter 1, p.11-12
NAVref4 Handbook of N&V, Chapter 1, p.14-15
NAVref5 Handbook of N&V, Chapter 1, p.11-12
Harris’ Shock and Vibration Handbook, Chapter 29, part III, Table 29.4, Harris, Cyril M,andPiersol, Allan G, McGraw-Hill, 2002, ISBN 978-0071370813
Noise at work: Guidance for employers on the Control of Noise at Work Regulations 2005, INDG362 (rev1), revised 10/05, p.2, Health & Safety Executive (UK), 2005 (leaflet: available online/downloadable or on paper from publisher)
NAVref6 Handbook of N&V, Part VII, p.829ff (machinery), Part VIII, p.1011ff (transport), Part IX, p.1149ff (transport interiors)
Industrial Noise Control and Acoustics, Chapter 5, Barron, R F, Marcel-Dekker, 2003, ISBN 0-8247-0701-X
NAVref7 Handbook of N&V, Chapter 55, p.668-669
NAVref8 Handbook of N&V, Chapter 1, p.14
Master Handbook of Acoustics, 4th Ed, Chapter 3, pp50-53, Everest, F A, McGraw-Hill, 2001
NAVref9 Handbook of N&V, Chapter 21, p.290; Chapter 23, p.304ff; Chapter 28, p.337
The Control of Noise at Work Regulations 2005: Guidance on Regulations, L108 2nd Edition, pp.10-17, pp.34-35, pp.87-95, Health & Safety Executive (UK), 2005, ISBN 978 0 7176 6164 4 (page numbers refer to online downloadable PDF edition)
NAVref10 Handbook of N&V, Chapter 57, p.708; Chapter 103, p.1244
NAVref11 Foundations of engineering acoustics, Chapter 7, p.140ff, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
NAVref12 Handbook of N&V, Chapter 2, p.21-22; Chapter 3, p.46
NAVref13 Handbook of N&V, Chapter 10, p.159-160
Harris’ Shock and Vibration Handbook, Chapter 29, part III, Harris, Cyril M,andPiersol, Allan G, McGraw-Hill, 2002, ISBN 978-0071370813
Springer Handbook of Acoustics, Chapter 8, p.257ff, Rossing, Thomas D (ed), Springer, 2007, ISBN 978-0-387-30446-5 (online e-book 978-0-387-30425-0)
NAVref14 Handbook of N&V, Chapter 7, p.102, Chapter 8, p.117
NAVref15 How To Get Started in Acoustics Analysis, Section 3, Tyrell, R J, NAFEMS, 1998
NAVref16 Handbook of N&V, Chapter 1, p.9, Chapter 6, p.79ff
NAVref17 Handbook of N&V, Chapter 2, p.27-28
How To Get Started in Acoustics Analysis, p.36, Tyrell, R J, NAFEMS, 1998
NAVref18 Handbook of N&V, Chapter 3, p.47
NAVref19 How To Get Started in Acoustics Analysis, p.12-13, Tyrell, R J, NAFEMS, 1998
Handbook of N&V, Chapter 1, p.13-14
NAVref20 Handbook of N&V, Chapter 9, p.128ff
NAVref21 Handbook of N&V, Chapter 6, p.94-97
NAVref22 Handbook of N&V, Chapter 6, p.95
NAVref23 Harris’ Shock and Vibration Handbook, Chapter 29, part III, Harris, Cyril M,andPiersol, Allan G, McGraw-Hill, 2002, ISBN 978-0071370813
NAVref24 Harris’ Shock and Vibration Handbook, Chapter 29, part III, Harris, Cyril M,andPiersol, Allan G, McGraw-Hill, 2002, ISBN 978-0071370813
NAVref25 Handbook of N&V, Chapter 2, p.19-20
NAVref26 Handbook of N&V, Chapter 2, p.23-24, Chapter 44, p.526ff
Foundations of engineering acoustics, Chapter 5, p.74, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
NAVref27 Foundations of engineering acoustics, Chapter 12, p.352, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
NAVref28 Handbook of N&V, Chapter 7, p.110-111; Chapter 9, p.129
NAVref29 Handbook of N&V, Chapter 103, p.1243
Foundations of engineering acoustics, Chapter 9.11, p.256ff, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
NAVref30 Handbook of N&V, Chapter 57, p.708
NAVref31 Foundations of engineering acoustics, Chapter 7, p.140ff, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
NAVref32 Foundations of engineering acoustics, Chapter 8.6, p.201, Fahy, F, Elsevier Academic Press, 2001, ISBN 978-0122476655
How To Get Started in Acoustics Analysis, p.29ff, Tyrell, R J, NAFEMS, 1998
NAVref33 Handbook of N&V, Chapter 8, p.122-123
How To Get Started in Acoustics Analysis, Section 6, Tyrell, R J, NAFEMS, 1998
Proceedings of the 2nd MSC Worldwide Automotive Conference, pp.1-14, “Panel contribution analysis by using acoustic reciprocity”, Yi Jong-Cheol, Macneal-Schwendler Corporation, Dearborn, MI, October 2000.
International Journal of Automotive Technology, Volume 10, Number 1, pp.79-85, “Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis”, Han, X, Guo, Y-J, Yu, H-D, and Zhu, P, Korean Society of Automotive Engineers, 2009, DOI 10.1007/s12239-009-0010-8
NAVref34 Handbook of N&V, Chapter 55, p.678-688
NAVref35 Handbook of N&V, Chapter 7, p.101ff
NAVref36 Handbook of N&V, Chapter 8, p.116ff
NAVref37 Handbook of N&V, Chapter 8, p.116-117
NAVref38 Handbook of N&V, Chapter 7, p.109-110; Chapter 8
NAVref39 Propagation of sound in porous media: modelling sound absorbing materials, p.343ff, Allard, J-F and Atalla, Nouredine, John Wiley and Sons, 2nd ed. 2009, ISBN 978-0470746615