Energy harvesting eel

TL;DR: In this article, the authors provide an overview of strategies for powering MEMS via non-regenerative and regenerative power supplies, along with recent advancements, and discuss future trends and applications for piezoelectric energy harvesting technology.

TL;DR: In this article, the optimal AC-DC power generation for a rectified piezoelectric device was investigated under steady-state operation, and the harvested power depends on the input vibration characteristics (frequency and acceleration), the mass of the generator, the electrical load, the natural frequency, the mechanical damping ratio and the electromechanical coupling coefficient.

TL;DR: The latest progress in kinetic energy harvesting for wide applications ranging from implanted devices and wearable electronic devices to mobile electronics and self-powered wireless network nodes is presented.

Abstract: Closed-loop turbulence control is a critical enabler of aerodynamic drag reduction, lift increase, mixing enhancement, and noise reduction. Current and future applications have epic proportion: cars, trucks, trains, airplanes, wind turbines, medical devices, combustion, chemical reactors, just to name a few. Methods to adaptively adjust open-loop parameters are continually improving toward shorter response times. However, control design for in-time response is challenged by strong nonlinearity, high-dimensionality, and time-delays. Recent advances in the field of model identification and system reduction, coupled with advances in control theory (robust, adaptive, and nonlinear) are driving significant progress in adaptive and in-time closed-loop control of fluid turbulence. In this review, we provide an overview of critical theoretical developments, highlighted by compelling experimental success stories. We also point to challenging open problems and propose potentially disruptive technologies of machine learning and compressive sensing.

TL;DR: In this paper, the authors showed that there exist two distinct types of response in a very low mass and damping regime, depending on whether one has a low combined mass-damping parameter (low m*ζ), or a high mass-ding parameter (highm*δ).

TL;DR: In this article, the authors examined the characteristic lengths of the oscillating wakes of bluff bodies and concluded that these are equivalent at high Reynolds number, leading to the conclusion that there are two simultaneous characteristic lengths; the scale of the formation region and the width to which the free shear layers diffuse.

TL;DR: In this paper, a semi-empirical study of the bluff body problem is presented, where interference elements in the wake close behind a cylinder demonstrate the need for considering that region in any complete theory.

TL;DR: In this article, the basic principle of fish propulsion is studied, and the thrust, power required, and energy imparted to the wake are calculated, and propulsive efficiency is also evaluated.