Related Experiment Video
Updated: May 21, 2025

Modeling and Experimental Analysis of the Single-Shaft Coaxial Motor-Pump Assembly in Electrohydrostatic Actuators
Published on: June 13, 2022
Power-efficiency constraint for chemical motors
1Graduate School of China Academy of Engineering Physics, Beijing 100193, China.
Abstract:
Chemical gradients provide the primordial energy for biological functions by driving the mechanical movement of microscopic engines. Their thermodynamic properties remain elusive, especially concerning the dynamic change in energy demand in biological systems. In this article, we derive a constraint relation between the output power and the conversion efficiency for a chemically fueled steady-state rotary motor analogous to the F_{0} motor of ATPase. We find that the efficiency at maximum power is half of the maximum quasistatic efficiency. These findings shall aid in the understanding of natural chemical engines and inspire the manual design and control of chemically fueled microscale engines.
Related Concept Videos
Electro-mechanical Systems
A key component of the DC motor is the armature, a rotating circuit positioned within a magnetic field. As an electric current passes through the...
Mechanical Efficiency of Real Machines
However, in reality, no machine can be truly ideal, and all of them experience some...
Back EMF
Force On A Current Loop In A Magnetic Field
Conservation of Energy in Control Volume
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
Power Expended by a Constant Force

