Isothermal Heat Engines Violate the Second Law of Thermodynamics

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pentch...@gmail.com

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Nov 13, 2021, 7:50:25 AMNov 13
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Misleading education:

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

The truth: One-temperature (isothermal) heat engines are commonplace - e.g. pH-sensitive polymers can do work, at the expense of ambient heat, as they swell or contract. No "two temperatures" involved:

https://www.researchgate.net/profile/Paul-Topham/publication/47426820/figure/fig1/AS:307404580376582@1450302371395/Illustration-of-a-volume-transition-in-a-cross-linked-polybase-network-triggered-by-a-pH.png

By adding and removing hydrogen ions (H+) one can cyclically extract work from pH-sensitive polymers - see Fig. 4 on p. 15 here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1367611/pdf/biophysj00645-0017.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. So lifting weights is the net work in the whole process. The second law of thermodynamics is clearly violated.

See more here: https://twitter.com/pentcho_valev

Pentcho Valev
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