This module is concerned with the area of acoustics and industrial noise. It is designed to develop and reinforce an understanding of several topics including waves, sound propagation, sound measurement and frequency analysis as well noise creation, measurement and control.
On successful completion of this module the learner should be able to explain certain related words and concepts, perform calculations, solve problems, apply concepts to new problems. They should be able to present, communicate and explain their ideas and solutions by several means such as report writing and presentations.
They should be able to plan and perform experiments, collect data, analyse data, present result
Waves and Vibration
Longitudinal waves, sound waves, production of sound waves. Free field propagation of sound waves, velocity of propagation-temperature dependence. Mathematical representation of plane progressive wave, interference of sound waves, beats, stationary waves and resonance. Reflection, refraction, diffraction of sound and its application to loudspeaker diaphragm.
Sound Measurement
Intensity of sound, specific acoustic impedance, intensity of spherical wave, concept of far field. Sound Intensity Level, Sound Pressure Level, Sound Power Level of Source. Addition and subtraction of sound levels, numerical problems. Weighting networks, phon scale, sones.
Microphones, sound level meters,vibration transducers.
Frequency Analysis, Frequency and Pitch, Musical scales, Percentage bandwidth filters, Sound Spectra using Fast Fourier Transform
· Sound Sources, Directivity of a point source,· Sound field due to point, line, plane sources, · Fans, motors, engines as sources,
Room Acoustics, Sound absorption, Reverberation Time of Room, Equations of Sabine and others, Intensity in reverberant field,· Sound Intensity Level due to combination of direct field and reverberant field,·
Effect of additional absorber Sound Transmission loss of a partition, the mass law, sound insulation.
Noise Measurement · Equivalent Continuous Noise Level; · Noise Dose and it's measurement, Required Equipment; · Health and Safety, National and International Regulations governing noise in the industrial and general environment.
Laboratory · Velocity of sound measurement using ultrasonic source and receiver; · Measurement of Sound Intensity Level in free field, calculation of associated loudness level in phons and sones; · Use of various percentage bandwidth filters to measure sound intensity levels in frequency bands, high-resolution frequency analysis of sound using FFT.
Lectures, tutorials, laboratory activities, demonstrations and brightspace or other approved University virtual learning environments.
This module will be taught through a hybrid of lectures, laboratory practice and online resources.
| Module Content & Assessment | |
|---|---|
| Assessment Breakdown | % |
| Formal Examination | 42 |
| Other Assessment(s) | 58 |