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![]() "Gilligan" wrote in message . .. | | "Paladin" noneofyourbusiness.www wrote in message | ... | | "Gilligan" wrote in message | . .. | | The propeller does boil the water. It is a scientific fact and I shall | offer | | irrefutable proof: | | | | http://www.brooklyn.cuny.edu/bc/ahp/MBG/MBG4/Joule.html | | | | Quotes: | | | | "In the following years he took to measuring the amount of heat | generated by | | every mechanical process he could think of. He enclosed wooden paddles | | inside an insulated container and used a falling weight to turn a shaft | and | | churn the paddles. Friction caused the water in the container to heat | up, | | and Joule measured the heat change. From this the work done could be | | compared with the amount of heat that had been produced. | | | | By 1843 he was ready to publish. Called the mechanical equivalent of | heat, | | this is value for the amount of work required to produce a unit of heat, | and | | is calculated as 41,800,000 ergs. (One erg is the work done in moving a | one | | gram mass through a one centimeter distance)." | | | | | | | | So, as one can plainly see that in the mid-1800's it was recognized that | the | | churning of propellers heat the water. In the case of the cavitating | | propeller, the slippage is so great that the energy that would normally | go | | into propelling a great ship forward goes, instead, into raising the | caloric | | content of the fluid medium surrounding said propeller causing boiling | and | | cavitation. | | | | Hence, the propeller boils the water, causing cavitation. | | | | My tea kettle has a propeller in it and boils water quite quickly with | no | | application of heat. | | | I'm not denying that mechanical energy applied to water will cause | its temperature to rise but it doesn't cause it to boil in the case | of a yacht's propeller. There isn't enough energy outputted to any | ship's propeller that can cause the ocean around it (and cooling it) to | boil. | No, it isn't the boiling of water that causes cavitation. It is the | lowering | of pressure that causes the water to vaporize. | | The very chart to which you posted a link proves this to be true. | http://encarta.msn.com/media_4615415...for_Water.html | It shows there are a couple ways to skin a cat. Water can | be vaporized by adding heat, or by lowering pressure. A prop might | add a tiny bit of heat but it subtracts great amounts of pressure. | It is the subtraction of pressure that causes cavitation. | | Ready to say UNCLE yet? | | | I can tell I am battling against a person of towering intellect who does not | back down when guided by the light of truth. | | I must give in and say Uncle. | | Who is this man so knowledgeable in the ways of science? | And, it's a rare pleasure to meet a man who's willing to learn and admit his (very rare) mistakes. But, I suppose you're as learned as you are because you're willing to consider alternate views with an open mind as well as a fondness for language as a tool and a standard. (unlike the likes of DSK). I'm willing to bet you're either a libertarian or a staunch Goldwater conservative. One must wonder. Does the faulty use of language produce a liberal or does liberalism result in a faulty use of language... Paladin -- Posted via a free Usenet account from http://www.teranews.com |
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