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Carnot efficiency is reachable in an irreversible process.

Jae Sung Lee1, Hyunggyu Park2

  • 1School of Physics and Quantum Universe Center, Korea Institute for Advanced Study, Seoul, 02455, Korea. jslee@kias.re.kr.

Scientific Reports
|September 8, 2017
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Summary
This summary is machine-generated.

This study demonstrates that Carnot efficiency is achievable in irreversible processes using the Feynman-Smoluchowski ratchet (FSR). Surprisingly, increasing irreversibility can enhance heat engine efficiency.

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Area of Science:

  • Thermodynamics
  • Statistical Mechanics
  • Non-equilibrium Physics

Background:

  • Conventional thermodynamic belief posits Carnot efficiency is limited to reversible processes.
  • No theorem prohibits Carnot efficiency in irreversible processes.
  • The Feynman-Smoluchowski ratchet (FSR) is a model system for studying heat engines.

Purpose of the Study:

  • To investigate if Carnot efficiency can be reached in an irreversible process.
  • To explore the role of irreversibility in heat engine efficiency.
  • To determine if the Feynman-Smoluchowski ratchet (FSR) can operate at Carnot efficiency.

Main Methods:

  • Theoretical analysis of the Feynman-Smoluchowski ratchet (FSR).
  • Investigation of entropy production in the FSR model.
  • Thermodynamic analysis of heat engine efficiency under irreversible conditions.

Main Results:

  • Carnot efficiency is achievable in an irreversible process via the FSR.
  • Increasing irreversibility can enhance the FSR's efficiency.
  • The FSR can indeed operate at Carnot efficiency, challenging prior assumptions.

Conclusions:

  • The Carnot efficiency is not strictly limited to reversible processes.
  • Irreversible processes can be harnessed to design efficient heat engines.
  • This work provides new insights into the operation of the Feynman-Smoluchowski ratchet and non-equilibrium thermodynamics.