Do bubbles heat up as they collapse?

1. May 29, 2007

KingNothing

In the video at http://www.spikedhumor.com/articles/108195/Real_Life_Creature_Assassin.html [Broken]

they say something about the "bubbles momentarily reach the temperature of the sun". I dont understand this bit at all, or how this mechanism works.

Last edited by a moderator: May 2, 2017
2. May 30, 2007

FredGarvin

If you're referring to cavitation bubbles, it can increase in temperature quite a bit. Here is a great on-line reference for bubble dynamics and cavitation:

http://caltechbook.library.caltech.edu/1/04/chap3.htm#L1 [Broken]

Here is the TOC of the book:
http://caltechbook.library.caltech.edu/1/04/content.htm [Broken]

This is a highly specialized field of study. I won't pretend to know anything except the very elemental aspects so I can't get into the deep physics of what is going on.

Last edited by a moderator: May 2, 2017
3. May 30, 2007

AlephZero

The surface temperature of the sun is about 5800 degK i.e. about 20 times the ambient surface temperature of the earth, so FredGarvin's factor of "4x10^4 times the ambient temperature" is more than enough to make the initial statement plausible.

4. May 30, 2007

cesiumfrog

Just from first principles:

- as a bubble decreases to zero radius, the internal pressure increases infinitly (http://hyperphysics.phy-astr.gsu.edu/hbase/surten2.html#c2").

- the shrinking of the bubble involves the condensation of gas into the surrounding liquid, which is a heating process (opposite of evaporation).

From this I'm naively (neglecting the atomic scale) tempted to conclude that the bubble remains at a "boiling temperature" that with pressure goes also to infinity as the bubble collapses.

Last edited by a moderator: Apr 22, 2017