"Gilligan" wrote in message . ..
| http://en.wikipedia.org/wiki/Boiling
|
|
|
| Boiling is the rapid vaporization of a liquid, which typically occurs when a
| liquid is heated to a temperature such that its vapor pressure is above that
| of the surroundings, such as air pressure. Thus, a liquid may also boil when
| the pressure of the surrounding atmosphere is sufficiently reduced, such as
| the use of a vacuum pump or at high altitudes. Boiling occurs in three
| characteristic stages, which are nucleate, transition and film boiling.
| These stages generally take place from low to high surface temperatures,
| respectively.
|
| Nucleate boiling is characterized by the incipience and growth of bubbles on
| a heated surface, which rise from discrete points on a surface, whose
| temperature is only slightly above the liquid’s saturation temperature. In
| general, the number of nucleation sites are increased by an increasing
| surface temperature. An irregular surface of the boiling vessel (i.e.
| increased surface roughness) can create additional nucleation sites, while
| an exceptionally smooth surface (such as glass) lends itself to
| superheating.
|
| When the surface temperature reaches a maximum value, the critical
| superheat, vapor begins to form faster than liquid can reach the surface.
| Thus, the heated surface suddenly becomes covered with a vapor layer.
| Because of the vapor layer’s lower thermal conductivity, this vapor layer
| insulates the surface. This condition of a vapor film insulating the surface
| from the liquid characterizes film boiling.
|
| Transition boiling may be defined as the unstable boiling, which occurs at
| surface temperatures between the maximum attainable in nucleate and the
| minimum attainable in film boiling.
|
|

Good info but mostly obfuscation to keeping from saying. "Oops, I
was wrong.

The facts of the matter that the verb boil means to heat to a temperature
at which a liquid vaporizes. I'm saying there is not enough heating going
on in a cavitating prop to vaporize water. Thus to say it boils is to speak
in error.

The fact of the matter is you used the word boil when you should have
corrected DSK and used vaporized instead. It's a pressure thing and
not a temperature thing,

Paladin


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