Acoustic theory

Detonation, Acoustical Theory of Shock Wapes is discussed in the book of Baum Stanyukovich Shekhter (1959), pp 206-08... 

EFFECT OF SURFACE REFLECTION ACOUSTIC THEORY NO CAVITATION PRESSURE... 

We have recently proposed a general acoustic theory for a dilute suspension of particles, which accounts for both of CVP and IVP [16-18]. Experimentally, the total vibration potential (TVP) between two points in the suspension, which is given by the sum of IVP and CVP, is observed. That is. 

If it is accepted that a spinning mode of propagation exists, then an acoustic theory may be applied to predict the spin frequency, the slope of the helical path on the tube wall, and other characteristics of spinning detonations [75]-[76]. For a planar Chapman-Jouguet wave in an infinitely long tube and in a frame of reference in which the burnt gas is at rest, the circumferential velocity of a traveling tangential acoustic wave at the wall... 

Amplification expressions in general are not as simple as equation (51) for two-phase flows in rocket motors [128]. Equilibrium and frozen sound speeds with respect to droplet behavior may be identified (compare Sections 9.1.4.6 and 4.2.6), and a mass-source term may arise in equation (51) in the development of a conservation equation for the acoustic energy in the gas. From the viewpoint of equation (14), the quantity O must include amplification effects that arise from both energy sources and mass sources. Acoustic theories may be derived from the conservation equations of Chapter 11 for the purpose of analyzing acoustic amplification in spray combustion. 

Rosenbaum J. F., Bulk Acoustic Wave Acoustic Theory and Devices (London Artech House Boston, 1988). 

The most well known acoustic theory for heterogeneous systems was developed by Epstein and Carhart (3), and Al-legra and Hawley (10). This theory takes into account the foiu most important mechanisms (viscous, thermal, scattering, and intrinsic) and is termed the ECAH theory. This theory describes attenuation for a monodisperse system of spherical particles and isvalid only for dilute systems. 

Another significant development is associated with the name of Samuel Temkin. He offers in his papers (22, 23) a new approach to acoustic theory. Instead of assuming a model dispersion consisting of spherical particles in a Newtonian liquid, he suggests that the thermodynamic approach be explored as far as possible. This very promising theory operates with notions of particle velocities and temperature fluctuations, and yields some unusual results (22, 23). It has not yet been used, as far as we know, in commercially available instruments. 

It has been determined that acoustic spectra are affected by bubbles. An acoustic theory describing sound propagation through bubbly liquid was developed by Foldy in 1944 (29), and confirmed experimentally in the 1940s and 1950s (30, 31). 

A filter is a mathematically defined system for modifying signals. In signal processing filters are put to many uses as their name might suggest they can filter out some unwanted portion of a signal. In speech synthesis, we are interested in them mainly because of the acoustic theory of speech production, (section 11.1), which states that speech production is a process by which a... 

There are three main techniques which make use of the classical acoustic theory of speech production model ... 

Fant, G. Acoustic Theory of Speech Production. Mouton, 1960. 

Klatt, D. H. Acoustic theory of terminal analog speech synthesis. In Proceedings of the International Conference on Acoustics Speech and Signal Processing 1972 (1972), vol. 1, pp. 131-135. 

The development of the source-filter model and the general acoustic theory of speech production by Fant and others (see Chapter 11) was a key breakthrough step and allowed the development of the type of formant synthesisers described here. The Parametric... 

Some very interesting drag-reduction studies have been performed by Marcus (1979)j coupling gas-solid flow with high-frequency oscillations superimposed on the flow system. A length dependency was found on the phenomenon of drag reduction, pointing to possible analysis by finite amplitude or acoustical theory to the two-phase flow system. 

Unless you are prepared to adopt a highly irrational approach to sound design, you should always give preference to basing your new instruments on well-documented acoustic theories see Howard and Angus (1996) for a good introduction to acoustics. Acoustic musical instruments are a reliable point of departure because the human ear is familiar with them. However, be wary here, because the expression point of departure does not necessarily mean that you should always attempt to imitate these instruments. Bear in mind that software sound synthesis gives you the power to create new instruments and sonorities. 

The use of decibels merely results in a rescaling of the Bode plot AR axis. The decibel unit is employed in electrical communication and acoustic theory and is seldom used today in the process control field. Note that the MATLAB bode routine uses decibels as the default option however, it can be modified to plot AR results, as done in Fig 14.2. In the rest of this chapter, we only derive frequency responses for simple transfer function elements (integrator, first-order, second-order, zeros, time delay). Software should be used for calculating frequency responses of combinations of these elements. 

---