Cavitation devices

Sivakumar and Pandit [13] reported the use of hydrodynamic cavitation for decolorization of dye effluent stream. It has been observed that for same flow area, plate with larger number of small diameter holes gives higher extent of color removal as compared to the plate with smaller number of larger diameter holes. The observed results have been explained on the basis of frequency of turbulence for the two cases. The hydrodynamic cavitation reactor using multiple hole orifice plates has been found to give cavitational yields, which are two times higher than the best acoustic cavitation device (Dual frequency flow cell with capacity of 1.5 L). 

Two cavitational devices manufactured by Five Star Technologies were used for synthesis and were the models CaviMax (a single-orifice processor, operating at a constant flow rate and variable pressures) and the CaviPro 300... 

CaviMax and CaviPro processors, 23-26 cavitational devices, 23-24 characterization of Reynolds and throat cavitation numbers, 25-27 classical approach, 18 copper-modified zinc oxide with crystallographic strain, 38-39 crystallographic strain by hydrodynamic cavitation, 34-39 engineered synthesis, 18-19 equipment for hydrodynamic cavitation, 21-22... 

Pressure at the pulsing device and the conditions for cavitation and water hammer may be estimated by the methods of Wilhams and Little [Trans. Jnst. Chem. Eng. (London), 32, 174 (1954)] provided the pressure-drop characteristics of the tower internals are known. Jealous and Johnson (loc. cit) have had good success in computing the power required for pulsing. Since power requirement alternates, the use of a flywheel on the pulse mechanism to act as an energy reservoir is suggested as a means of reducing power requirements. Alterna-... 

Cavitation in pipe systems is possible wherever there are changes in section or flow direction such as expansions, bends and branches. However, serious erosion problems are normally only associated with components within which flow is severely constricted and consequently accelerated. If pumps are excluded then, in most systems, this situation applies to devices used... 

Since 1945 an increasing understanding of the phenomenon of cavitation has developed coupled with significant developments in electronic circuitry and transducer design (i. e. devices which convert electrical to mechanical signals and vice versa). As a result of this there has been a rapid expansion in the application of power ultrasound to chemical processes, a subject which has become known as Sonochemistry . 

There are a large number of industrial processes which employ cavitation as an energy source for the generation of fine emulsions and dispersions. One of the earliest devices which was developed for this purpose was the so-called liquid whistle (see Chapter 7) and this continues to be used widely. Typical examples of the uses of such whistles include the preparation of emulsion bases for soups, sauces or gravies which consist of a premix of water, milk powder, edible oil and fat together with flour or starch... 

The formation of one or more cavities(air spaces or voids) in cast-loaded solid, expl or proplnt c hges is called cavitation (See under Loading of Ammunition). A cavity in a HE chge of a shell may cause premature expln in the gun because of collapse of the chge under the force of acceleration. A cavity in a propint chge may affect its ballistic characteristics(Ref 1). Cavities in loaded ammo may be discovered by x-ray devices such as Betatron(qv)... 

Chow et al. (2004) reported dynamic video images of the influence of ultrasonic cavitation on the sonocrystallization of ice at a microscopic level. The ultrasonic device was used in combination both with an optical... 

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