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Entropy production in irreversible processes with friction
1Associação Euratom-IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, 1049-001 Lisboa, Portugal. bizarro@ipfn.ist.utl.pt
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 15, 2008
Summary
This study generalizes entropy production to explicitly include friction as an irreversibility source. It clarifies how frictional work contributes to entropy increase alongside heat exchange.
Area of Science:
- Thermodynamics
- Physical Chemistry
- Statistical Mechanics
Background:
- Entropy production is a key concept in understanding irreversible processes.
- Existing models often do not explicitly account for frictional dissipation.
- Friction represents a significant source of irreversibility in many physical systems.
Purpose of the Study:
- To generalize established entropy production expressions.
- To explicitly incorporate friction as a source of irreversibility.
- To provide a clearer interpretation of entropy increase contributions.
Main Methods:
- Mathematical formulation of entropy production.
- Inclusion of frictional work as a heat source.
- Decomposition of entropy increase into heat exchange and dissipated work.
Main Results:
- Generalized entropy production equations incorporating friction.
- Quantification of entropy increase due to both heat transfer and frictional dissipation.
- Distinction between heat exchanged and frictional work lost within the system.
Conclusions:
- Friction is a quantifiable source of irreversibility affecting entropy production.
- The generalized framework reduces ambiguity in interpreting entropy changes.
- This approach offers a more comprehensive understanding of thermodynamic processes involving friction.
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