Thermodynamic engine powered by anisotropic fluctuations

Inertialess Gyrating Engines

“…C. Remark on the forced-pendulum abstraction It was noted in [1,2,12] that, in both examples, the resulting dynamical system's behaviour resembles that of the damped pendulum with constant torque [28], i.e., to a system that behaves according to (1) with…”

“…We remark that in the model proposed by [1], the temperature is more generally expressed as a function of both θ and ω. Specifically, the temperature's dependence on the angular position of the engine is delayed by a factor of τ ω, with sin(θ − ωτ ) replacing sin(θ) in (2). However, experimental evidence [1] suggests that τ = 15 × 10 −3 [sec].…”

“…The second example is that of a Brownian gyratorbased engine that was recently introduced in [2]. This consists of the coupling between an electrical system, known as the Brownian gyrator [21], and a mechanical subsystem with an inertial wheel.…”

“…As long as there is enough time-scale separation between the mechanical and the electrical subsystems, as shown in [2], the dynamics of the Brownian gyrating engine obey (1) with…”

“…This model captures the general principle behind a wide range of mechanisms that convert thermal/chemical energy to rotary motion, whether synthetic or natural, from steamengines to biomolecular motors. We focus on two different types of gyrating engines, a low-temperature-differential Stirling engine [1] that draws power from a temperature differential and a Brownian gyrating engine powered by Nyquist-Johnson thermal noise of two resistors kept at different temperature [2]. The salient feature in embodiments of these devices is the inertia needed to average out fluctuations and ensure sustained operation.…”