Water droplets

Water injection in thermal engines and the famous "pantone engine". General informations. Press clippings and videos. Understanding and scientific explanations on the injection of water into engines: ideas for assemblies, studies, physico-chemical analyzes.
Other
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Water droplets




by Other » 03/11/09, 20:18

Hello


I just read this in article for icing on airplanes

the question that I ask myself on reading this document, is it possible that droplets of a certain size remain in droplets above 100C?


http://www.msc-smc.ec.gc.ca/education/a ... r_12_f.cfm

The droplets remaining in the liquid state at temperatures below the freezing point are said to be supercooled. While cooling, they do not systematically freeze at 0º C. There is however a limit to their cooling without there being freezing, a limit depending mainly on the size of droplets.

The larger ones freeze at temperatures slightly below the freezing point, while the smaller ones can remain liquid down to -40º C. Below this temperature, they are rare.

An supercooled droplet freezes at the slightest shock, that is to say the moment it touches the device. The latent heat it gives off immediately increases its temperature. If the temperature of the droplet was not too cold at the start, it will increase until it reaches 0º C.
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Alain G
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by Alain G » 04/11/09, 00:56

Hi Andrew!

I know that the water of a moving river can descend a few degrees below the freezing point, it freezes when it is no longer in motion.

Now above 100C, it may be possible for a few degrees because atmospheric pressure plays a role on the point of freezing and boiling, less pressure and it freezes and boils at lower temperature.

In height at lower pressure it freezes at a lower point and hitting the edge of the wing the pressure increases and the water freezes, at least that is theoretically what can happen.
:D
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Stepping behind sometimes can strengthen friendship.
Criticism is good if added to some compliments.
Alain
Other
Pantone engine Researcher
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by Other » 04/11/09, 02:59

Hello


while the smallest can remain liquid down to -40º C. Below this temperature, they are rare.


An supercooled droplet freezes at the slightest shock,


I was trying to understand something that I experienced several years ago with a 100% Pantone montage that works with a mixture of alcohol and water.
at a certain speed the inlet of the gel reactor at the level of the small carburetor of reduced model and the inlet of the rod becomes cold.
I wondered, if the noise, like sand rubbing in the reactor, was it not very small droplets of ice?
and that's when the system was working at its best
I think I haven't finished learning about the water droplets
and their behavior at different temperatures ..
Mico droplets and liquid water do not have the same properties at all.



Andre
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Alain G
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by Alain G » 04/11/09, 03:29

Good evening André

It is true that the humidity contained in the air, even at -20C remains in the form of vapor or micro droplet.

For freezing at the inlet of the reactor it is created due to the vacuum just like a refrigerant in a refrigerator, on vacuum packaging machines fitted with vacuum pumps sometimes I detect leaks by simply touching them by testing the pipes or other parts to feel a cooler part, moreover if I put water in these machines and maintain the vacuum, the water little sometimes formed a frima on the surface but for that I must have water containing a lot oxygen so that the boiling is as high as possible.

Unfortunately I have not experienced the pantone but the noise could it not come from the shock wave such as on a nozzle outlet of a jet engine.

:D
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Stepping behind sometimes can strengthen friendship.

Criticism is good if added to some compliments.

Alain

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