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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Universal Bounds on Fluctuations in Continuous Thermal Machines.
Sushant Saryal1, Matthew Gerry2, Ilia Khait2
1Department of Physics, Indian Institute of Science Education and Research, Pune 411008, India.
Physical Review Letters
|November 19, 2021
Summary
This study establishes fundamental bounds on energy conversion device fluctuations. Output current fluctuations are limited by input current fluctuations, with efficiency-dependent upper and lower bounds.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Condensed Matter Physics
Background:
- Understanding energy conversion efficiency and fluctuations is crucial for device performance.
- Steady-state thermodynamics governs the behavior of energy conversion devices.
Purpose of the Study:
- To derive fundamental bounds on the ratios of fluctuations in steady-state time-reversal energy conversion devices.
- To establish relationships between output and input current fluctuations and their bounds.
Main Methods:
- Analysis in the linear response regime.
- Derivation of fluctuation bounds based on efficiency.
- Application to specific devices like thermoelectric junctions and quantum refrigerators.
Main Results:
- The relative fluctuations of output power are lower bounded by the relative fluctuations of input heat current.
- Upper and lower bounds on the ratio of output to input current fluctuations are determined by the engine's average and Carnot efficiency, respectively.
- Lower bound saturation occurs in the tight-coupling limit.
Conclusions:
- The derived fluctuation bounds are universally applicable to various energy conversion devices and regimes.
- Findings suggest broader applicability of these bounds beyond the linear response regime, supported by numerical simulations.
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