ultrasonic cavitation and implosion self presenting

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Fundamentals of Ultrasonic Cavitaton

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Sound . . .Sound . . .Sound Is Vibration Transmitted Through an Elastic Material

UltraSound . . .UltraSound . . .Sound at a Higher Frequency

Sound

UltraSound

Sound is Created by a Source of Vibration

Think of the black line above as the edge view of a metal plate

Sound is Created by a Source of Vibration

Now Imagine an “Ultrasonic Transducer” Attached to the Metal Plate

Ultrasonic Transducer

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Ultrasonic Transducer

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Sound is Created by a Source of Vibration

The Ultrasonic Transducer Vibrates and Transmits Vibration to the Metal Plate

Now Imagine that the Metal Plate is the Bottom of a Vessel or “Tank”

Now Imagine that the Metal Plate is the Bottom of a Vessel or “Tank”

And that the Tank is Filled with Liquid

And that the Tank is Filled with Liquid

Now Let’s Re-Start the Vibration

Now Let’s Re-Start the Vibration

Now Let’s Re-Start the Vibration

Now Let’s Re-Start the Vibration

Now Let’s Re-Start the Vibration

Now Let’s Re-Start the Vibration

As the tank bottom raises, it pushes against the liquid thereby

compressing it. The blue represents an area of “compression”.

The “compression” continues to travel through the liquid away from the source of vibration.

As the tank bottom lowers it “pulls” on the liquid creating an area of negative pressure

or “rarefaction”

Continued vibration generates areas of

compression and rarefaction radiating through the liquid

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Now add a pressure gauge to measure pressure at a given point in the liquid

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As the rarefactions and compressions of the sound waves pass by, the gauge sees alternating negative and positive pressure

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As the rarefactions and compressions of the sound waves pass by, the gauge sees alternating negative and positive pressure

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As the rarefactions and compressions of the sound waves pass by, the gauge sees alternating negative and positive pressure

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A vibrating source transmits sound waves to a liquid.

Sound waves, consisting of areas of rarefaction (negative pressure) and compression (positive pressure), radiate through the liquid away from the source of vibration.

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Imagine now a small defect in the liquid consisting of a bubble or speck of dirt

.

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The a “cavitation bubble” starts to grow around the defect under influence of negative pressure

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Growth of the “cavitation bubble” continues and

accelerates under increasingly negative pressure

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Growth of the “cavitation bubble” continues and

accelerates under increasingly negative pressure

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Growth of the “cavitation bubble” continues and

accelerates under increasingly negative pressure

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Growth of the “cavitation bubble” continues and

accelerates under increasingly negative pressure

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The “cavitation bubble” shrinks under the influence of growing

positive pressure

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The catastrophic collapse of the cavitation bubble under

increasing pressure results in implosion!

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The high energy resulting from the implosion of millions of

cavitation bubbles do the work associated with ultrasonics

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