Propeller Cavitation

The propeller reaches 45 rotations per second near the end of the test.

Category:

Science & Technology

Tags:

• Propeller
• Cavitation
• кавитация
• на
• винта
• kavitaciq
• cavitation
• kavitacia

[magnavox50]

Hey what was the prop made out of? and did anyone check to see how much material had been lost from the propeller as a result of the RPM's? just curious!

[metalqga]

The prop is a model of a ship's propeller and the materials used are the same. The guy didn't tell us what the loses are, but next to this test tank there was a big prop with some huge holes in the blades. He told us that the prop with the holes had been used by a fast ferry on underwater wings(we call it a comet) for two years.

[jerzkid87]

losses? you mean to material of the propeller? if so thats fascinating. im studying architecture and have always been interested in naval architecture and the idea of micro losses of materials.

[metalqga]

The effect is called cavitational corrosion. As well as corrosion cavitation causes vibrations and noise, that's why cavitation is to be avoided at all costs. (using normal props; supercavitation props work using the effect of the cavitation).

[luckyD1993]

why are ppl laughing like drunks in the back groud?

[TiHawk]

Another interesting thing about this cavitation tube is, that to be able to see the cavitation effect clearly, the light inside the tube flashes with the same frequency the propeller rotates, so it creates the illusion that the propeller doesn't actually rotate, and the spiral is static. just felt like mentioning it ;)

[billkoumparos]

Propellers work according to Bernoulli's principle thus the pressure at leading edge is very low and hence water is vaporized even at low temperature. it is highly undesirable as it causes loss of efficiency o propeller, vibration, noise and cavitation-corrosion (as the cavities implode the create a continuous variation of pressure and they destroy the metal of the ships hull around the propeller)

[aboriani]

@halo6tee9 ROFL almost pissed myself laughing

[halo6tee9]

at. 0:02 it sounds like Chewbacca is watching it too.

[reddog694uk]

Does this mean that heat is generated within the cavitational vacuum or as a later consequence of it?

[CharlyGK7]

which movie?

[Vicious3027]

pretty good explanation. Tom Clancy is one of my favorite authors, and Hunt for Red October is one of my favorite movies :)

[Yodainacan]

Thanks for explaining this for me, Ingareineinar! I felt pretty stupid for a while. :-D

[ingareinar007]

Hi! Ofcourse the "eggboiling" is just theoretical. But the cavitation makes a unwanted pressure that leads to boiling. And after some time you can see small holes like there has been worms. It eats up the propeller, makes noise normally and gives less thrust normally. As "metalqga" over says, it is called cavitational corrosion. Excuse my poor English.

[Yodainacan]

Ingareinar007, does the propeller actually heat so much because of the cavitation, or is the "cooking an egg" effect because of the pressure differences?