EC2053 ENGINEERING ACOUSTICS

EC2053 ENGINEERING ACOUSTICS L T P C

3 0 0 3

UNIT I ACOUSTICS WAVES 9

Acoustics waves - Linear wave equation – sound in fluids – Harmonic plane waves –

Energy density – Acoustics intensity – Specific acoustic impedance – spherical waves –

Describer scales.

Reflection and Transmission:

oblique incidence – method of images.

Transmission from one fluid to another normal and

UNIT II RADIATION AND RECEPTION OF ACOUSTIC WAVES 9

Radiation from a pulsating sphere – Acoustic reciprocity – continuous line source -

radiation impedance - Fundamental properties of transducers.

Absorption and attenuation of sound

Absorption from viscosity – complex sound speed and absorption – classical absorption

coefficient

UNIT III PIPES RESONATORS AND FILTERS 9

Resonance in pipes - standing wave pattern absorption of sound in pipes – long

wavelength limit – Helmoltz resonator - acoustic impedance - reflection and transmission

of waves in pipe - acoustic filters – low pass, high pass and band pass.

Noise, Signal detection, Hearing and speech

Noise, spectrum level and band level – combing band levels and tones – detecting

signals in noise – detection threshold – the ear – fundamental properties of hearing –

loudness level and loudness – pitch and frequency – voice.

UNIT IV ARCHITECTURAL ACOUSTICS: 9

Sound in endosure – A simple model for the growth of sound in a room – reverberation

time - Sabine, sound absorption materials – measurement of the acoustic output of

sound sources in live rooms – acoustics factor in architectural design.

Environmental Acoustics:

Weighted sound levels speech interference – highway noise – noise induced hearing

loss – noise and architectural design specification and measurement of some isolation

design of portions.

UNIT V TRANSDUCTION 9

Transducer as an electives network – canonical equation for the two simple transducers

transmitters – moving coil loud speaker – loudspeaker cabinets – horn loud speaker,

receivers – condenser – microphone – moving coil electrodynamics microphone

piezoelectric microphone – calibration of receivers.

TOTAL= 45 PERIODS

TEXT BOOK:

1. Lawrence E.Kinsler, Austin, R.Frey, Alan B.Coppens, James V.Sanders,

Fundamentals of Acoustics, 4th edition, Wiley, 2000.

REFERENCE:

1. L.Beranek , “Acoustics” - Tata McGraw-Hill