Explain "you can't pump steam"
Explain "you can't pump steam"
(OP)
Can someone pls explain why is that steam can't be pumped? I don't see why. I found the so called fourth law of thermodynamics saying so. Thanks.
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Explain "you can't pump steam"
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RE: Explain "you can't pump steam"
When steam is released from the Boiler it will travel a very long distance with out any supplemental boost. This is because there is more steam coming along behind the first release.
You need to study the science of Steam before you go on: http://science.howstuffworks.com/steam-technology....
You also need to stop listing to the Beauregard Gustsafisan's of this world (Look is up).
Sometimes its possible to do all the right things and still get bad results
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
The most common form of pump, the centrifugal pump, works great with liquids, and not so great with gases. Once primed, they can lift water a few feet. ... unless the water flashes to steam or delivers a big bubble of some other gas, then the pumping stops.
(
Centrifugal compressors are topologically similar to centrifugal pumps, but run at much higher speeds, have smaller clearances and better balance, and do pump gas.
)
Mike Halloran
Pembroke Pines, FL, USA
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
MJCronin
Sr. Process Engineer
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Explain "you can't pump steam"
I think it is really semantics, "pumps" terminology is used for liquid or liquid like fluids such as dense phase gases, whereas compressors are used for gases.
The energy in steam is different from gases or liquids as the condensation and superheating nature is used.
I'm not sure BI description is correct - pressure is pressure regardless of fluid type and for any fluid to flow there needs to be a pressure difference between the two points caused by elevation or induced pressure. Gas complicates things by expanding as well but both simply move from a high pressure location to a lower pressure location.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
Your comment above about gas compression etc is related more to the energy stored in a pipeline due to pumps or compressors and I agree with that, but don't think it applies in terms of the question asked.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
Centrifugal pumps will not "pump" gasses; virtually impossible to add energy to gas using centrifugal pump.
Positive displacement pumps are another story however.
A good real-world example would be multiphase pumps (typically of the twin or 3-screw pump variety). They can pump gasses and liquids simultaneously and in separate slugs. Semantics comes into play here because this "pump" is really acting as a compressor when handling gas slugs, and as a true PD pump with liquids.
Don't see how this is much more than a philisophical argument.
RE: Explain "you can't pump steam"
Whereas nothing changes as the result of the discussion, it is obviously totally philosophical, to the philosophers, however the physicist might be willing to argue that point too.
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
Generally, a compressor starting with a vapour saturated in some component, generates a superheated vapour. The mechanical inefficiency of the machine to some degree ensures that. However, that is not to say that trying to compress a condensable vapour which condenses at a temperature much higher than ambient, doesn't have significant issues associated with it- assuming there's an actual reason to try to do it in the first place. Compressors of many designs tend not to like to handle condensate in any quantity, at least not in the long term. The heat transfer that is often required to keep compressors durable in the long term, can tend to generate condensate at least at start-up unless it is managed properly.
RE: Explain "you can't pump steam"
RE: Explain "you can't pump steam"
Mixed refrigerants in LNG plants do something similar; a heavier solvent dissolves the lighter ends under pressure after compression, and the light ends are later released at lower pressure for chilling at the low temp end of the cooling profile.
So to make something like this happen for steam, you'll need to find a suitable solvent for steam ?
RE: Explain "you can't pump steam"
A Swedish submersible pump company used on their pumps a spring loaded discharge port which would close when pumping and open during times there wasn't any water flow - it opens to allow air to be pumped as an aid to motor cooling - it was reasonably effective and backed up by thermal sensor in the windings.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)