| Cavitation damage (updated) |
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| Deutsche Militärverteidigung - Bundeswehr | |||
| Συντάχθηκε απο τον/την Χρήστος Μπούμπουλης (Christos Boumpoulis) | |||
| Κυριακή, 26 Νοέμβριος 2017 19:39 | |||
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Ultrasonic Signal Generator Circuit – Beijing Ultrasonic
www.youtube.com/watch?v=A9JdQN5e5G8
Ultrasonic soldering
https://www.youtube.com/watch?v=sI_xtZLuvIo video ultrasonic soldering System
www.youtube.com/watch?v=ZvJ5355jKz4 Cavitation damage
Cavitation is, in many cases, an undesirable occurrence. In devices such as propellers and pumps, cavitation causes a great deal of noise, damage to components, vibrations, and a loss of efficiency. Cavitation has also become a concern in the renewable energy sector as it may occur on the blade surface of tidal stream turbines.
When the cavitation bubbles collapse, they force energetic liquid into very small volumes, thereby creating spots of high temperature and emitting shock waves, the latter of which are a source of noise. The noise created by cavitation is a particular problem for military submarines, as it increases the chances of being detected by passive sonar.
Although the collapse of a small cavity is a relatively low-energy event, highly localized collapses can erode metals, such as steel, over time. The pitting caused by the collapse of cavities produces great wear on components and can dramatically shorten a propeller or pump's lifetime.
After a surface is initially affected by cavitation, it tends to erode at an accelerating pace. The cavitation pits increase the turbulence of the fluid flow and create crevices that act as nucleation sites for additional cavitation bubbles. The pits also increase the components' surface area and leave behind residual stresses. This makes the surface more prone to stress corrosion.
Ultrasonic cleaning is a process that uses ultrasound (usually from 20–400 kHz) and an appropriate cleaning solvent (sometimes ordinary tap water) to clean items. The ultrasound can be used with just water, but use of a solvent appropriate for the item to be cleaned and the type of soiling present enhances the effect. Cleaning normally lasts between three and six minutes, but can also exceed 20 minutes, depending on the object to be cleaned.
Ultrasonic cleaners are used to clean many different types of objects, including jewelry, lenses and other optical parts, watches, dental and surgical instruments, tools, coins, fountain pens, golf clubs, fishing reels, window blinds, firearms, car fuel injectors, musical instruments, gramophone records, industrial parts and electronic equipment. They are used in many jewelry workshops, watchmakers' establishments, and electronic repair workshops.
Brain shrinkage seen on MRI imaging may actually occur up to 10 years before Alzheimer’s disease is diagnosed, finds a new study in Neurology.
“This measure is potentially an important imaging marker of early changes in the brain associated with Alzheimer’s disease that could help predict who might develop the dementia associated with this disease and possibly even how long it would be before dementia develops,” says study researcher Bradford Dickerson, MD, a neurologist at Harvard Medical School in Boston, in a news release. “These are preliminary results that are not ready to be applied outside of research studies right now, but we are optimistic that this marker will be useful in the future.”
About 5.4 million people in the U.S. have Alzheimer’s disease, a progressive brain disease that leads to a decline in memory and other cognitive abilities. It is the most common form of dementia, according to the Alzheimer’s Association.
There is no single test that can diagnose Alzheimer’s, but an early diagnosis could lead to more therapeutic opportunities.
A couple of, a 20 KHz 100W 110/220v ultrasonic Generator Circuit with a 20KHz 100W ultrasonic cleaning transducer can be found in the market worth 66 USD.
Above, there is raw technical information for further research.
Christos Boumpoulis
economist
P.S.: Those, who may cook alive, healthy, sane, honest and legitimate civilians, exclusively, for political reasons and under the illegitimate cover-up of enlisted charlatans, are, according to my opinion, nothing else but nearly-men and quasi zombies.
Note: The photo was found here, https://cdn2.bjultrasonic.com/wp-content/uploads/2012/12/25KHz-100W-110V-Ultrasonic-Generator-PCB-Circuit.jpg.
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| Τελευταία Ενημέρωση στις Τετάρτη, 29 Νοέμβριος 2017 18:02 |
