Aims

The aims of the course are to:

• analyse and solve a range of practical engineering problems associated with acoustics.

Objectives

As specific objectives, by the end of the course students should be able to:

• understand what sound is and how we perceive it
• understand how sound is generated and propagated
• understand the acoustics of a wide range of music and noise production

Content

We will analyse and solve a range of practical engineering problems associated with acoustics. Examples include modelling of noise sources from jets, fans, musical instruments, human voice, kettles, dripping taps, whistling mice, singing flames, etc. We will also study ways to reduce noise either at the source or through acoustic damping. Upon completion of this module, the students would be well placed to pursue academic research in the area of acoustics and related fields or to work in industry (the topics covered in the course is of interest to GE, Rolls-Royce, Airbus, Dyson, Mitsubishi Heavy Industries, automotive companies, music and biomedical industries, and acoustic consultancies).

What is sound and how does it propagate? (5L) (Dr A Agarwal)

• Introduction
• The wave equation
• Some simple 3D wave fields (plane waves, surface waves and spherical waves)
• Sound transmission through different media

Simples sounds sources (2L) (Dr A Agarwal)

• Pulsating sphere
• Oscillating sphere
• Example: loudspeaker with and without a cabinet

General solution to wave eqn (2L) (Dr. A Agarwal)

• Green's function
• Sound from general mass and force sources (examples, Bliz siren and singing telephone wires)

Jet noise (Dr A Agarwal) (1 L)

• Scaling of jet noise. How much does jet noise increase by if we double the jet's velocity?
• What do jets and tuning forks have in common?
• Lighthill's acoustic analogy
• Sound of aircraft jets and handdriers 

Duct acoustics (2 L) (Dr A Agarwal)

• Rectangular ducts (example, sound box)
• Low-frequency sound in ducts
• Circular ducts
• Acoustic liners (Helmholtz resonator, blowing over a beer bottle)

Musical acoustics & everyday things (3L) (Drs A Agarwal)

• String instruments 
• Wind instruments 
• Brass instruments 
• Whistling of steam kettles and Rayleigh's Bird Call
• Acoustics of dripping taps

Vocalisation (0.5 L) (Dr A Agarwal)

• Human speech, singing and overtone singing
• Mice mating calls

Fan noise (1L) (Dr A Agarwal)

• Rotor alone noise
• Rotor-stator interaction noise

Thermoacoustics instability (0.5 L) (Dr A Agarwal)

• Rijke tube experiment (singing flames)

This syllabus contributes to the following areas of the UK-SPEC standard:

Toggle display of UK-SPEC areas.

 
Last modified: 24/05/2022 12:55