We consider a heavy piston in an infinite cylinder surrounded by ideal gases on both sides. The piston moves under elastic collisions with gas atoms. We assume here that the gases always exert equal pressures on the piston, hence the piston remains at the so called mechanical equilibrium. However, the temperatures and densities of the gases may differ across the piston. In that case some earlie...

A wet-plate clutch (Fig. 1) is a mechanical device that transmits torque from its input axis to its output axis by means of friction. The input axis of the clutch is connected to a drum, which is a hollow cylinder with grooves on the inside. A first set of friction plates (clutch plates) with external toothing that can slide in those grooves are pressed against a second set of friction plates (...

In the pneumatically actuated leg control system, precise control of the piston position and the pressure of cylinder chambers is a tricky problem. In this paper, a new control scheme is introduced, in which the gas internal energy of the cylinder’s two chambers is used as the set point for PD controller. The proposed control scheme is essential to control the piston position and the chamber pr...

We revisit the paradigm of an ideal gas under isothermal conditions. A moving piston performs work on an ideal gas in a container that is strongly coupled to a heat reservoir. The thermal coupling is modeled by stochastic scattering at the boundaries. In contrast to recent studies of an adiabatic ideal gas with a piston [R.C. Lua and A.Y. Grosberg, J. Phys. Chem. B 109, 6805 (2005); I. Bena, Eu...

A compressed air energy storage (CAES) system that uses a high pressure, isothermal air compressor/expander (C/E) has no carbon emission and is more efficient than a conventional system that uses fossil fuels. To be successful, the compressor/expander must be efficient and has high power density. However, there is a trade-off between efficiency and power density due to heat transfer. Our previo...

Low spatial frequencies of atmospheric turbulence are specially troublesome to astronomers because the phase distortions they cause have large amplitude. We have begun experiments at the Multiple Mirror Telescope (MMT) to remove these errors with tip, tilt, and piston control of pieces of the wave front defined by the telescope’s six 1.8 m primary mirrors. We show long exposure images taken at ...

In this work, a generalized expression of the photoacoustic ~PA! effect in a multilayer material is derived. This expression takes thermal and optical properties and geometry of a multilayer structure, as well as the thermal contact resistances between layers into consideration. In addition, a composite piston model consisting of a thermal piston and a mechanical piston of the PA effect is deve...

We compare two approaches for a Markovian model in flexible manufacturing systems (FMSs) using Monte Carlo simulation. The model which is a development of Fazlollahtabar and Saidi-Mehrabad (2013), considers two features of automated flexible manufacturing systems equipped with automated guided vehicle (AGV) namely, the reliability of machines and the reliability of AGVs in a multiple AGV jobsho...

We examine a rod piston-rotaxane system, where the positions of several mobile rings on the axle are controlled by an external force acting on one of the rings. This allows us to access the translational entropy of the rings. For a simple rotaxane molecule with an axle that has uniform ring-axle interactions along its length, the molecule behaves like a miniature piston filled with a one-dimens...