Acoustic engineering


This page is related to the Acoustics part of the Vibrations and acoustics MECA-H-411 BRUFACE course. For the Vibrations part, please visit Arnaud Deraemaeker’s page.




  • Textbook in French
  • Textbook in English + an alternative text presenting the material covered during the first three lectures (September 20, October 4 and 11).
  • A set of videos in English presenting most of the book’s content.
  • This public directory contains the slides used during each lecture as well as all material of the ACTRAN exercise sessions.
  • ACTRAN is a software used during the exercise sessions and for the project.
    • ACTRAN must be installed on your own Windows or Linux computer before October 28.
    • ACTRAN is also available on the desktops of the UB4 PC rooms.


Lectures (9×2 = 18h) :

  • Room S.R42.4.502 (Solbosch Campus, Solvay Building, 4th floor, room 502)
  • 20.09, 04.10, 11.10, 18.10, 25.10, 08.11, 16.11, 23.11 (link to the slides: see above)
  • Always from 08:00 to 10:00 (even on October 25th … contrary to what was initially announced)

Exercises = preparation for the project (3×2 = 6 hours):

  • 28.10 (16:00-18:00) – S.UD2.208 – Auditoire DECROLY
  • 10.11 (08:00-10:00), 17.11 (08:00-10:00) – S.UB4.126, S.UB4.130 – Salle Socrate

Project (3 x 4 = 12 hours):

  • To be performed at home, alone or in groups of up to four students, between November 17 and December 20.
  • On December 21st, from 08:00 to 10:00, an optional written control on the outcome of the project will be organized. Students who have a mark of 10 or more may elect not to discuss the project during the oral exam in January or August. Their mark at the written optional control will then be used in calculating the overall mark (40% acoustics, 20% vibrations and 20% project).

Detailed course content

Reference is made to the book (see links to French and English version above). There are videos illustrating / presenting most sections of the book. You obviously only have to study what has been seen during the lectures; this is a minor subset of the book content and is described below.

  1. Acoustic quantities
    • Pressure, velocity, intensity, impedance, admittance:
      everything there is to know is contained in this document.
    • Sound pressure level and sound intensity levels: main reference is chapter 7 of the book
  2. Acoustic phenomena
    1. Plane waves: section 6.5 of the book
    2. Attenuation: section 6.5.4 of the book
    3. Reflection:
      • Normal incidence: section 8.1 of the book
      • Oblique incidence: since I did not present the related theory, I just expect you to know the Descartes law (figure 8.4 in the book)
    4. Resonances:
      • Sections 9.1 and 9.2 of the book
      • You must be able to calculate analytically the resonance frequencies and acoustic modes of a duct with any mix of boundary conditions on the left and right end.
      • You must be able to schematically draw the expected response function (example: figure 9.2) and modal pressure distribution (example: figure 9.3).
      • These skills will be tested on December 21st.
    5. Transfer matrix method:
      • Understand the concept of the transfer matrix method: decomposition of a silencer in simple elements, calculation of the transfer matrix of this element, composition of the transfer matrices.
      • These elements have been studied: simple duct, cross section change, insertion of a resonator in derivation, quarter-wavelength and Helmholtz resonator.
      • Understand the difference between TL and IL (Transmission Loss and Insertion Loss).
      • Be aware that the Transfer Matrix Method is valid up to a maximum frequency where the plane wave hypothesis is no longer valid. No demonstration required.
    6. I will document the other topics as we go.