Quote:
Originally posted by bigben2k
Otherwise, the expansion of water over the temperature range that's typical, would amount to a maximum of 5 drops of water, which most systems should be able to handle.
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. . . yeah.
English or metric drops, Ben?
Sigh.
Anyway, the deal with liquids is that they do expand very little with temperature. If they are kept perfectly sealed, then yes, they will create some impressive pressure - fluids don't like to be compressed. But, as you say, only a little bit of breather room - a small hole in a reservoir, or even a totally sealed system with ~10 cc's of air somewhere for the water to compress - will keep pressure in the system from getting high enough to burst anything.
This is, of course, barring extreme cases where there is a pump failure and one particular part of the system heats up enough to either melt or burst the tubing near a waterblock.
In a totally sealed system such as an in-line system with no air in a reservoir or trap of some sort, it's at least possible that the shift in temperature from ambient to operating, which could be as much as 20 degees C, which would translate to an increase in volume of 0.6% at constant pressure or an increase of pressure of 2000 psi at constant volume.
The flexibility of the tubing in the system will probably account for most of the volume change and prevent a pressure increase anywhere near that high, but the fact remains that
if water is highly constrained, like in a system with very inflexible tubing and no airspace, water
can burst a WC system just by being heated a few degrees.
Fluids do not like being compressed. Give your precious fluids room, and you can maintain purity of essence.
This has been a public service announcement.
Alchemy
Cite: NIST Webbook
http://webbook.nist.gov/cgi/fluid.cg...85&Action=Page