unlined straight ducts [8].Table 13.12 In‐duct attenuation within externally lagged straight ducts [8].Table 13.13 Sound attenuation dB/m of unlined sheet metal ducts at one‐octave...Table 13.14 Predicted attenuation, dB, of a 610 mm × 610 mm unlined, 10 m lon...Table 13.15 Predicted attenuation in decibels of a 610 mm × 610 mm lined, 6 m...Table 13.16 Calculated attenuation values in decibels for 10 m long duct in E...Table 13.17 End reflections, dB, obtained from Figures 13.56 and 13.57.Table 13.18 Attenuation (dB) of unlined mitre bends. Attenuation is given for...Table 13.19 Attenuation in decibels of lined mitre bends [8].Table 13.20 Sound pressure level predictions for breakout noise in Example 13...Table 13.21 Sound pressure level, dB, predicted in Example 13.15.
12 Chapter 14Table 14.1 Comparison of rolling and power train A‐weighted sound pressure le...Table 14.2 A‐weighted sound pressure levels from pass‐by measurements of two ...Table 14.3 Automotive applications [39].
13 Chapter 15Table 15.1 Possible airport actions to abate noise [43].Table 15.2 Data for an aircraft noise event of five seconds.Table 15.3 A‐weighted aircraft noise level events in an airport.
14 Chapter 16Table 16.1 Penalties for aircraft noise applied by ANSI to original Schultz c...Table 16.2 Example of a community noise ordinance.Table 16.3 Data used in Example 16.2.
List of Illustrations
1 Chapter 1Figure 1.1 Examples of different types of signals and their spectral content...Figure 1.2 Time and frequency domain representations of (a) pure tone; (b) c...Figure 1.3 Periodic sound signal.Figure 1.4 Frequency spectrum of the periodic signal of Figure 1.3.Figure 1.5 Random noise signal.Figure 1.6 Time and frequency domain representations of the transient respon...Figure 1.7 Time and frequency domain representations of the transient respon...Figure 1.8 Power spectral density of random noise.Figure 1.9 Different types of filter. Low‐pass, high‐pass, band‐pass, and ba...Figure 1.10 Typical frequency response of a filter of center frequency fC an...Figure 1.11 Comparison between bandwidths of (a) constant percentage and (b)...Figure 1.12 Simplified block diagram of a parallel‐filter real‐time analyzer...Figure 1.13 Conversion from FFT spectra to a constant percentage bandwidth (
2 Chapter 2Figure 2.1 Representation of simple harmonic motion by projection of the rot...Figure 2.2 Simple harmonic motion.Figure 2.3 Simple harmonic motion with initial phase angle ϕ.Figure 2.4 Displacement, velocity, and acceleration.Figure 2.5 Movement of mass on a spring: (a) static deflection due to gravit...Figure 2.6 Movement of damped simple system.Figure 2.7 Motion of a damped mass–spring system, R < (4MK)1/2.Figure 2.8 Forced vibration of damped simple system.Figure 2.9 Dynamic magnification factor (DMF) for a damped simple system.Figure 2.10 Force transmissibility, TF, for a damped simple system.Figure 2.11 Two‐degree‐of‐freedom system.Figure 2.12 Mode shapes for the two‐degree of freedom system shown in Figure...Figure 2.13 Harmonically forced two‐degree‐of‐freedom system.Figure 2.14 Forced response spectra of a damped two‐degree of freedom system...Figure 2.15 Undamped dynamic vibration absorber defined in Example 2.9.Figure 2.16 First four mode shapes of a cantilever beam.Figure 2.17 Velocity level of a fully‐clamped rectangular plate as a functio...Figure 2.18 First six modes of a rectangular plate.Figure 2.19 Computed velocity level of a simply‐supported rectangular plate ...
3 Chapter 3Figure 3.1 Schematic illustration of the sound pressure distribution created...Figure 3.2 Plane waves of arbitrary waveform.Figure 3.3 Simple harmonic plane waves.Figure 3.4 Some typical sound pressure levels, Lp.Figure 3.5 Some typical sound power levels, LW.Figure 3.6 Diagram for combination of two sound pressure levels or two sound...Figure 3.7 Imaginary surface area S for integration.Figure 3.8 Sound intensity In, being measured on (a) segment dS of an imagin...Figure 3.9 Sound intensity probe microphone arrangement commonly used.Figure 3.10 Source above a rigid surface.Figure 3.11 Polar directivity plots for the radial sound intensity in the fa...Figure 3.12 Geometry used in derivation of directivity factor.Figure 3.13 Incident intensity Ii, reflected intensity Ir, and transmitted i...Figure 3.14 Refraction of sound in air with wind speed U(h) increasing with ...Figure 3.15 Refraction of sound in air with normal temperature lapse (temper...Figure 3.16 Refraction of sound in air with temperature inversion.Figure 3.17 Example of monopole. On the monopole surface, velocity of surfac...Figure 3.18 Sound pressure level in an interior sound field.Figure 3.19 Sound absorption coefficient α of typical absorbing materia...