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Isothermal Heat Engines Disobey the Second Law of Thermodynamics



 
 
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  #1  
Old March 28th 19, 12:00 PM posted to sci.astro
Pentcho Valev
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Default Isothermal Heat Engines Disobey the Second Law of Thermodynamics

Misleading education:

"A necessary component of a heat engine...is that two temperatures are involved" http://physics.bu.edu/~duffy/py105/Heatengines.html

Actually one-temperature (isothermal) heat engines are commonplace - e.g. pH-sensitive polymers can cyclically do work as they swell or contract. No "two temperatures" involved:

https://pbs.twimg.com/media/Dqasx5_WoAAV6XY.jpg

By adding and removing hydrogen ions (H+) one can cyclically extract work from pH-sensitive polymers:

https://pbs.twimg.com/media/DmP8OHKXcAAerSI.jpg

(This is Fig. 4 on p. 15 he https://www.ncbi.nlm.nih.gov/pmc/art...00645-0017.pdf)

Adding and removing H+, per se, consumes no work if done QUASISTATICALLY. This means that the work lost e.g. in adding is compensated by the work gained in removing, and the net work involved is zero.

In his famous lectures

http://www.feynmanlectures.caltech.edu/I_44.html

Feynman discusses the non-isothermal analog which, at least apparently, doesn't violate the second law:

http://readingpenrose.files.wordpres...and-engine.gif

In the isothermal case the two temperatures are replaced by "adding and removing H+" which, if performed QUASISTATICALLY, consumes no work. So the system just lifts weights for us, at the expense of ambient heat and in violation of the second law of thermodynamics.

Heat engines working under isothermal conditions (no "two temperatures") and able to violate the second law of thermodynamics are commonplace. They are too slow and impuissant to be of any technological importance, and this is one of the reasons why scientists pay them no attention. Yet there seems to be an exception: When water is placed in an electric field, the non-conservative force (pressure) that emerges in the bulk triggers vigorous (by no means impuissant) motion apparently able to convert ambient heat into work quite efficiently:

https://www.youtube.com/watch?v=17UD1goTFhQ

Pentcho Valev
  #2  
Old March 28th 19, 12:53 PM posted to sci.astro
Pentcho Valev
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Posts: 8,078
Default Isothermal Heat Engines Disobey the Second Law of Thermodynamics

Triply distilled water in an electric field undergoes turbulent motion:

https://www.youtube.com/watch?time_c...&v=17UD1goTFhQ

The motion can do work, e.g. by rotating a waterwheel. This work will be done at the expense of

(A) electric energy?

(B) ambient heat?

The correct answer is (B) - the second law of thermodynamics is false.

Note that the water is triply distilled so the current is reduced to minimum - obviously the current cannot be responsible for the work done. Moreover, the motion starts before the bridge is formed - this implies that the motion can only be powered by ambient heat.

Godfathers killed physics in more than one way:

https://pbs.twimg.com/media/DmP7MrTWsAMFHwx.png

Pentcho Valev
  #3  
Old March 28th 19, 09:59 PM posted to sci.astro
Pentcho Valev
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Posts: 8,078
Default Isothermal Heat Engines Disobey the Second Law of Thermodynamics

Water rises and then goes down as the capacitor is switched on and off:

"Physics Demonstration of the Force on a liquid dielectric in an electric field" https://www.youtube.com/watch?v=Cs8nAeJZeWc

"Liquid Dielectric Capacitor" https://www.youtube.com/watch?v=T6KAH1JpdPg

"Rise in level of liquid dielectric in capacitance" https://www.youtube.com/watch?v=uHNmzcYp6JE&t=358s

The systems can do mechanical work - e.g. by regularly lifting floating weights. The work will be done at the expense of ambient heat (clearly not at the expense of electric energy - in the last video this is more than obvious), in violation of the second law of thermodynamics.

Pentcho Valev
 




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