Modeling an efficient Brownian heat engine
arXiv:0801.4599 · doi:10.1140/epjb/e2008-00308-5
Abstract
We discuss the effect of subdividing the ratchet potential on the performance of a tiny Brownian heat engine that is modeled as a Brownian particle hopping in a viscous medium in a sawtooth potential (with or without load) assisted by alternately placed hot and cold heat baths along its path. We show that the velocity, the efficiency and the coefficient of performance of the refrigerator maximize when the sawtooth potential is subdivided into series of smaller connected barrier series. When the engine operates quasistatically, we analytically show that the efficiency of the engine can not approach the Carnot efficiency and, the coefficient of performance of the refrigerator is always less than the Carnot refrigerator due to the irreversible heat flow via the kinetic energy.
8 pages and 14 figures
References in corpus (10)
- Brownian motors: noisy transport far from equilibrium
- Brownian motors
- Brownian motors: current fluctuations and rectification efficiency
- Inattainability of Carnot efficiency in the Brownian heat engine
- Tight coupling in thermal Brownian motors
- Heat Flow and Efficiency in a Microscopic Engine
- Forcing inertial Brownian motors: efficiency and negative differential mobility
- Energetics of a simple microscopic heat engine
- Exploring the operation of a tiny heat engine
- Optimal barrier subdivision for Kramers' escape rate
Cited by in corpus (4)
- Stochastic thermodynamics, fluctuation theorems, and molecular machines
- Optimal potentials for temperature ratchets
- Thermally activated barrier crossing and stochastic resonance of a flexible polymer chain in a piecewise linear bistable potential
- Stochastic energetics of a Brownian motor and refrigerator driven by non-uniform temperature