sonarluminescence
Posted: Thu Jun 04, 2009 6:54 pm
a discussion forum for Polywell fusion
https://talk-polywell.org/bb/
There is a laser experiment - zapping light bulbs with terrawatt pulses to improve efficiency - big laser huh? You can plug it into the wall socket.Skipjack wrote:Now, I dont know what "liquid" this is. It might be one with a very high boiling point (must be a pretty interesting fluid indeed). Yet I am still surprised, that at "tens of thousands of degrees" that this "star" supposedly has, the surrounding fluid does not start to boil?
The issue there is temperature, not heat. Very, Very, Very tiny bit of really, really hot matter.Skipjack wrote:Now, I dont know what "liquid" this is. It might be one with a very high boiling point (must be a pretty interesting fluid indeed). Yet I am still surprised, that at "tens of thousands of degrees" that this "star" supposedly has, the surrounding fluid does not start to boil?
I read about that one. Sounded pretty interesting at the time. I am a sceptic regarding the new laws they made in the EU (basically banning the old lightbulbs in favor of the supposedly better neon bulbs). This law is as always favoring two big companies and will make my chandelier in the living room a lot uglier. Thanks EU. So any development in that regard is welcome.There is a laser experiment - zapping light bulbs with terrawatt pulses to improve efficiency - big laser huh? You can plug it into the wall socket.
I dont quite understand how that answers my question. I have something that is supposedly very hot in a fluid. Unless there is some sort of insulation that heat will somehow radiate, or conduct into the fluid. At tens of thousands of degrees it should not take long for the surrounding fluid to boil, even if this tiny bit of matter is very small. Unless it I did not judge the size correctly. The video was rather sparce with real facts and instead showed some rather meaningless "pretty pictures".The issue there is temperature, not heat. Very, Very, Very tiny bit of really, really hot matter.
From http://en.wikipedia.org/wiki/SonoluminescenceSkipjack wrote:I dont quite understand how that answers my question. I have something that is supposedly very hot in a fluid. Unless there is some sort of insulation that heat will somehow radiate, or conduct into the fluid. At tens of thousands of degrees it should not take long for the surrounding fluid to boil, even if this tiny bit of matter is very small. Unless it I did not judge the size correctly. The video was rather sparce with real facts and instead showed some rather meaningless "pretty pictures".The issue there is temperature, not heat. Very, Very, Very tiny bit of really, really hot matter.
E.g. it would be nice to know what fluid. How big is that bubble, etc.
Sorry Dan, you got that backward. Easy to do. A billion Joules IS a large amount of energy. It is a billion watt seconds. A million kilowatt seconds. 278 kilowatt hours.D Tibbets wrote:Eg: a billion joules sounds like alot of energy, but if it is contained in a laser pulse that lasts for only one nanosecond, it amounts to only one Watt of power.
Usually clean water.Skipjack wrote:Now, I dont know what "liquid" this is. It might be one with a very high boiling point (must be a pretty interesting fluid indeed). Yet I am still surprised, that at "tens of thousands of degrees" that this "star" supposedly has, the surrounding fluid does not start to boil?
Either clean water with low levels of dissolved noble gassses (they make the light significantly brighter) or, in the case of fusion experiments, deuterated acetone. The reason you can see it so well, is that millions of bubbles form and burst in the same spot a second. It looks like a continuous light source. They learned how to do that in the 80's. It is a standing pressure wave. Neat stuff, but I doubt it is a path to fusion. I would, however, be happy to be wrong on that.KitemanSA wrote:Usually clean water.Skipjack wrote:Now, I dont know what "liquid" this is. It might be one with a very high boiling point (must be a pretty interesting fluid indeed). Yet I am still surprised, that at "tens of thousands of degrees" that this "star" supposedly has, the surrounding fluid does not start to boil?
One thing to remember about bubbles oscillating in a liquid due to sonic excitation is that the fluid tends to evaporate into the bubble as it grows, cooling the liquid, and part of the vapor gets injected deep into the liquid as the bubble collapses. This tends to transfer heat that would normally accumulate near the bubble more broadly. And, of course, some of the remaining energy goes to creating the glow. None-the-less, eventually it will heat, perhaps to the point where the oscillation frequency changes and the excitation drops so much that the phenomenon stops.
Obviously, it is still being studied with interest in some quarters.
Err... I hate it when I have to think. Once prodded by Kitemen , I realized that I was indeed reversing the relationship. Oh well, consider what I meant, but ignor what I said...KitemanSA wrote:Sorry Dan, you got that backward. Easy to do. A billion Joules IS a large amount of energy. It is a billion watt seconds. A million kilowatt seconds. 278 kilowatt hours.D Tibbets wrote:Eg: a billion joules sounds like alot of energy, but if it is contained in a laser pulse that lasts for only one nanosecond, it amounts to only one Watt of power.
I think what you met to say was that a billion Watts sounds like a lot of power, but if it lasts for a nano second it is only one Joule.