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SECTION II – OPERATION
PRINCIPLES OF ULTRASONIC DISRUPTION
The ultrasonic electronic generator transforms AC line power to a 20 KHz signal that
drives a piezoelectric converter/transducer. This electrical signal is converted by the
transducer to a mechanical vibration due to the characteristics of the internal
piezoelectric crystals.
The vibration is amplified and transmitted down the length of the horn/probe where the
tip longitudinally expands and contracts. The distance the tip travels is dependent on
the amplitude selected by the user. As you increase the amplitude setting the sonication
intensity will increase within your sample.
In liquid, the rapid vibration of the tip causes cavitation, the formation and violent
collapse of microscopic bubbles. The collapse of thousands of cavitation bubbles
releases tremendous energy in the cavitation field. The erosion and shock effect of the
collapse of the cavitation bubble is the primary mechanism of fluid processing.
Please consult with a product specialist for assistance with selecting a probe for your
application.
Relationship of Amplitude and Wattage
Sonication power is measured in watts. Amplitude is a measurement of the excursion of
the tip of the probe (probe is also known as a horn).
Some ultrasonic processors have a wattage display. During operation, the wattage
displayed is the energy required to drive the radiating face of a probe, at that specific
amplitude setting against a specific load, at that particular moment. For example, the
unit experiences a higher load when processing viscous samples then when compared
to aqueous samples.
The speed /cruise control on an automobile, can, to a certain extent, be compared to an
Ultrasonic Processor. The speed/cruise control is designed to ensure that the vehicle
maintains a constant rate of travel. As the terrain elevations change, so do the power
requirements. The cruise control senses these requirements, and automatically adjusts
the amount of power delivered by the engine in order to compensate for these ever
changing conditions. The greater the terrain rate of incline and greater the resistance to
the movement of the vehicle, the greater the amount of power that will be delivered by
the engine to overcome that resistance and maintain a constant speed.
The ultrasonic processor was designed to deliver constant amplitude, to your liquid
sample, regardless of these changes in load (much like the vehicle's cruise control
described above). As a liquid is processed, the load on the probe will vary due to
changes in the liquid sample (i.e. viscosity, concentration, temperature, etc.). As the
resistance to the movement of the probe increases (increased load on the probe),
additional power will be delivered by the power supply to ensure that the excursion at the
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