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Updated: Dec 24, 2025

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Stochastic heat engine using an active particle
Aradhana Kumari1, P S Pal2, Arnab Saha3
1Department of Physics, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India.
Abstract:
The topic of microscopic heat engine has undergone intensive research in recent years. Microscopic heat engines can exploit thermal as well as active fluctuations to extract thermodynamic work. We investigate the properties of a microscopic Stirling's engine that uses an active (self-propelling) particle as a working substance, in contact with two thermal baths. It is shown that the presence of activity leads to an enhanced performance of the engine. The efficiency can be improved by increasing the activity strength for all cycle time, including the nonquasistatic regime. We verify that the analytical results agree very well with our simulations. The variation of efficiency with the temperature difference between the two thermal baths has also been explored. The optimum region of operation of the engine has been deduced, by using its efficient power (product of efficiency and power) as a quantifier. Finally, a simple model is provided that emulates the behavior of a flywheel driven by this engine.
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