Boiling H20 freezes

[chillerman2006]

Here's a link to a video of water in an Vacuum chamber boiling then freezing

http://www.youtube.com/watch?v=Par-jcV2tPc

[simon@parker]

is this what happens when you pull a vacume to quickly ? as i remember being told something like this but i seem to have a gap in my memory as to who and when

[chillerman2006]

is this what happens when you pull a vacume to quickly ? as i remember being told something like this but i seem to have a gap in my memory as to who and when

Yeah, thats it mate

Its the reason behind a triple vac

When you pull a vacuum it will vapourise water untill it has used up the available heat/energy & then the water just freezes

[Peter_1]

Mmmm, nice video Chillerman, where did you filmed this or get it?

[chillerman2006]

Mmmm, nice video Chillerman, where did you filmed this or get it?

Had it so long now mate - can't remember where it came from :eek:

[Peter_1]

Well, in fact, I made this video ;-) And it is not in an environmental chamber but in a vacuum chamber. There are some pictures of this chamber on RE

[chillerman2006]

Well, in fact, I made this video ;-) And it is not in an environmental chamber but in a vacuum chamber. There are some pictures of this chamber on RE

OOH ! I hope your not gonna have me for copyright, Boss :eek:

Good job I did not try to tell you porkies (lies) :D

[Magoo]

Hi
every apprentice should veiw this video.

[desA]

Amazing. Thanks to the OP & Peter... If you have more such useful videos, I'd love to see them.

[newbie]

I'm a 2nd year apprentice and i think that was a brilliant video...but if water freezes during the vac will that not just leave ice/water/moisture in the pipe?

[Peter_1]

I'm a 2nd year apprentice and i think that was a brilliant video...but if water freezes during the vac will that not just leave ice/water/moisture in the pipe?

You are right and not right. This bottle was placed in vacuum chamber where the vacuum process is going very, very fast with huge pumps. Imagine the pumps stored in a place as big as a small house for a chamber of +/- 2 x2 m (space filled with pumps stacked and with the chamber is +/- 10 x 15 m) Then the achived vacuum is something we only can dream of..they'"re working on a molecular level of vacuum, UHV (ultra High Vacuum). UHV is in the range of 10 (-79) Pa or 140 (-9) torr. Some systems uses additional molecular vacuum pumps to speed up the process. Price: < 25,000 €/pump and there are sometimes 8 pumps on a chamber.http://t0.gstatic.com/images?q=tbn:ANd9GcQqyhn54VqiOwQ9QXLLUXoZFxOcMKlTcXO_bP0-r-BrxBm5apun
The vacuum process is going that fast that the needed energy to vaporize isn't going fast enough through the plastic of the bottle with freezing as a result. The energy is faster removed then it is added.
What we better had done was continuing the process and we should have seen sublimation of the ice. But the operator of this machine can't afford long standstills of his machine.

We almost bought one 2 years ago at Philips Brussels where we should have use it to freezedry documents after water damages of inventories. This is a very nice application of this chambers.

[r.bartlett]

http://www.youtube.com/watch?gl=GB&hl=en-GB&v=tlQ5gpbgilo

[chillerman2006]

RB - do we get an explanation then

[r.bartlett]

RB - do we get an explanation then

No can do as I wasn't there...

[chillerman2006]

Well not 100% & running the risk here of becoming Peter's signature

We have 3 gaseous base elements here 2 in the water and 1 with the introduction of nitrogen

along with any refrigerant that may or may not be present

Whilst pulling a vacuum oil is also often removed

The frozen substance is a mixture of H20+N (or maybe refrigerant) + oil

caused by pulling a vacuum too quickly & the hygroscopic feature of the oil in use

I have been informed that using the larger vac pumps on smaller systems is an issue

No experience of this though as I do not normally work on them

do not have mr o'brien 's email to hand or that copy of service engineer

can anyone confirm ?

[newbie]

@Peter_1....so eventually the vacuum would evaporate the ice?

[r.bartlett]

Well not 100% & running the risk here of becoming Peter's signature

We have 3 gaseous base elements here 2 in the water and 1 with the introduction of nitrogen

along with any refrigerant that may or may not be present

Whilst pulling a vacuum oil is also often removed

The frozen substance is a mixture of H20+N (or maybe refrigerant) + oil

caused by pulling a vacuum too quickly & the hygroscopic feature of the oil in use

I have been informed that using the larger vac pumps on smaller systems is an issue

No experience of this though as I do not normally work on them

do not have mr o'brien 's email to hand or that copy of service engineer

can anyone confirm ?

http://hvac-talk.com/vbb/showthread.php?t=378742

[chillerman2006]

http://hvac-talk.com/vbb/showthread.php?t=378742

cheers, I'll have a butchers after dinner

[chillerman2006]

hey

can not log in to that site + do not wish to join

i am expecting the old argument of nitrogen does not help evac - just pushes out oxy

the answer we need though is exactly what is the substance in the video

better to tell us than post a link no-one can view surely

:rolleyes:

[r.bartlett]

hey ricky

can not log in to that site + do not wish to join

i am expecting the old argument of nitrogen does not help evac - just pushes out oxy

the answer we need though is exactly what is the substance in the video

better to tell us than post a link no-one can view surely

:rolleyes:

As I say I wasn't there as this was well after I left fridgetech so I haven't got a clue..

[chillerman2006]

As I say I wasn't there as this was well after I left fridgetech so I haven't got a clue..

Get out of it - if you worked with Marc you must do, surely

You make me jealous of any training you got there now!

[mad fridgie]

If we look at his fingers, it seems that the only residue is oil. I would suspect that there is refrigerant trapped into a water/oil mix (solid), when heat is added the refrigerant just boils out of the mix (similar to the reason you have a crankcase heater)

[chillerman2006]

Thanks Mad

much appreciated
:D

[monkey spanners]

It also makes a pingy noise as it goes round the bends in the pipework....

[chillerman2006]

It also makes a pingy noise as it goes round the bends in the pipework....

Interesting - I have a cone I use for listening to bearings & now pipework, yeah makes sense

[mikeref]

OOH ! I hope your not gonna have me for copyright, Boss :eek:

Good job I did not try to tell you porkies (lies) :D
Classic!! Honesty is always the best policy;). I've always liked the saying, what goes around, comes around.

[chillerman2006]

Classic!! Honesty is always the best policy;). I've always liked the saying, what goes around, comes around.

Yep, I like to be up front & honest with people

& when I read back through the posts, I think Peter tactfully give me just enough rope to hang myself :D