Ads
related to: ultrasonic cavitation prediction
Search results
Results From The WOW.Com Content Network
The cavitation number (Ca) can be used to predict hydrodynamic cavitation.It has a similar structure as the Euler number, but a different meaning and use: . The cavitation number expresses the relationship between the difference of a local absolute pressure from the vapor pressure and the kinetic energy per volume, and is used to characterize the potential of the flow to cavitate.
Ultrasonic cavitation inception will occur when the acceleration of the ultrasound source is enough to produce the needed pressure drop. This pressure drop depends on the value of the acceleration and the size of the affected volume by the pressure wave. The dimensionless number that predicts ultrasonic cavitation is the Garcia-Atance number.
Because cavitation can only occur in liquids, chemical reactions are not seen in the ultrasonic irradiation of solids or solid–gas systems. For example, in chemical kinetics , it has been observed that ultrasound can greatly enhance chemical reactivity in a number of systems by as much as a million-fold; [ 15 ] effectively acting to activate ...
An ultrasonic examination. Ultrasound is sound with frequencies greater than 20 kilohertz. [1] This frequency is the approximate upper audible limit of human hearing in healthy young adults. The physical principles of acoustic waves apply to any frequency range, including ultrasound.
Cavitation: Ultrasound of high enough intensity causes water to boil, creating cavitation. This physically annihilates living organizsm and the supporting biofilm. One concern is to the potential effect on the hull. Cavitation [3] can be predicted mathematically through the calculation of acoustic pressure.
Prediction of symptoms of cavitation: Image title: An analysis which indicates some of the basic problems in cavitation and which may permit the prediction of cavitation characteristics of hydraulic equipment is presented. Some experimental results are discussed and are compared with the results of the analysis.
Sonication can be used for the production of nanoparticles, such as nanoemulsions, [5] nanocrystals, liposomes and wax emulsions, as well as for wastewater purification, degassing, extraction of seaweed polysaccharides [1] and plant oil, extraction of anthocyanins and antioxidants, [6] production of biofuels, crude oil desulphurization, cell disruption, polymer and epoxy processing, adhesive ...
MI is a unitless number that can be used as an index of cavitation bio-effects; a higher MI value indicates greater exposure. Levels below 0.3 are generally considered to have no detectable effects. Currently the FDA stipulates that diagnostic ultrasound scanners cannot exceed a mechanical index of 1.9. [3]