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Old 08-11-2009, 09:27 PM   #9 (permalink)
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Originally Posted by some_other_dave View Post
It's been used for torpedoes for quite a while... I thought the main point was to cut down on surface drag by making sure that most of the length of the torpedo is not in contact with the water?

At a somewhat higher speed, the same thing occurs in air. I can't find the formula to confirm speed, but it's based on the density of the fluid medium through which one is traveling.

Water is one of the easiest mediums to test it in, due to it's extreme density compared to other fluids, and the fact that it's clear as well.

IIRC, the speed at which cavitation is achieved is inversely proportionate to the density of the fluid (which seems obvious), i.e. the fluid is less dense, the speed is higher. I believe I recall reading something at one point which mentioned that necessary speed is related to the square of the density of the fluid medium, but that may be a cross-memory from another technical paper.
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