Water Vapour Temperature/ Chart

[Refrigerologist]

Does anyone have a water vapour/temperature relationship graph for vacuum conditions? I did have one given to me by Business Edge when I attended the Gas Handling Course, but of course I never photo copied the original and have lost it.

[Brian_UK]

Found something, may not be what you need really but it's a start.

http://www.unesco.org/webworld/ramp/html/r8707e/r8707e06.htm

I did have some tables on my pooter somewhere but can't find them yet, I'll keep looking.

[SteinarN]

Does anyone have a water vapour/temperature relationship graph for vacuum conditions? I did have one given to me by Business Edge when I attended the Gas Handling Course, but of course I never photo copied the original and have lost it.

Here are your chart :)
The chart is without numbers on most of the lines, but if you download the free program you can easily find the correct numbers and write them in the chart.

An excelent free program:
http://www.chemicalogic.com/steamtab/companion/default.htm

[nike123]

Try Kirkothemers

I tried in Google!;)

http://tinyurl.com/2rsxg6

[Tesla]

Try Kirkothemers

[Refrigerologist]

Thanks guys for your help.

SteinarN the SteamTab from Chemicallogic is perfect. I am not worried about enthalpy etc. I just wanted to use the pressure temperature relationship to shorten the first and second vaccing times on a triple vac as there is no need to pull down to 500microns on the first or second vac if the ambient is high enough.

[SteinarN]

I had been looking for a log P-h chart for water for several years. I found it only recently along with Steam Tab. I have calculated a steam engine with it.

40 bar abs pressure, 400C outlet, double expansion, reheat to 300C, expansion to 0,2 bar abs, (-0,8 bar rel) 65C with a condenser, and pump up to 40 bar again into the boiler. It give an efficiency of 28% at an isentropic engine efficiency of 0,85. Boiler efficiency not taken into account.

Will be a challenging project to take on!

[nike123]

SteinarN, you have all that in Coolpack as refrigerant R718.
This is example:
http://farm3.static.flickr.com/2200/2341569464_82358a0086_o_d.jpg

http://farm3.static.flickr.com/2092/2340753221_e09a487155_d.jpg

[SteinarN]

I wasnt aware of that program up until a month ago.
Yes, all the data is there, but the log P-h diagram lack the superheated and supercritical area. Not usable to create a steam engine cycle.

Edit: And you just destroyed the layout of this thread with those way to wide screenshots.:D

Edit 2: But you are right, better saturation tables, in fact not possible at all to print a table from Steam Tab.

Edit 3: Do not take notice of the first edit.

[nike123]

How about now!
http://farm3.static.flickr.com/2179/2341700312_f14f875df7_o_d.jpg

[SteinarN]

Uhhh, I havent been fiddling enough with the program yet. :o I just figured it out.

But you destroyed the layout once again!

[nike123]

Uhhh, I havent been fiddling enough with the program yet. :o I just figured it out.

But you destroyed the layout once again!

Try Firefox, ful screen and big monitor!:D

[US Iceman]

Large monitors are a blessing when your eye sight starts to go!:o But they do strange things to screens sometimes.:D

[Refrigerologist]

Thanks Nike, I had forgotten about Coolpack I have that loaded on my old laptop, so I will take a look. As I said I am not looking to do anything complex, just trying to cut down my vaacing times!!

[nike123]

Thanks Nike, I had forgotten about Coolpack I have that loaded on my old laptop, so I will take a look. As I said I am not looking to do anything complex, just trying to cut down my vaacing times!!

Some experts says (I read that on some articles on web, before), if you reach 500 microns and it stays stable below 700 after that for an hour (i think 1 hour but I need to check this), that job is done. And, that triple evacuation is not necessary any more, with use of electronic vacuum gauge, because, now we have mean to see end result of our actions.
By them, triple evacuation is heritage of times when we did not have electronic micron gauge and, waist of time and money, if you have result as above. To me, that make sense.