– An adiabatic piston, separating two granular gases prepared in the same macro-scopic state, is found to eventually collapse to one of the sides. This new instability is explained by a simple macroscopic theory which is furthermore in qualitative agreement with hard disk molecular dynamics. The problem of the so-called adiabatic piston was described in 1960 by Callen [1] and has received a lot...

Gas compression in a positive displacement (PD) type piston engine, or piston compressor, has long been modeled as a quasi-static process in which the piston is assumed to move infinitely slow inside a cylinder. The gas compression mechanism is therefore regarded as being governed by the basic thermodynamic principles. Energy transfer is accomplished quasi-statically with a piston reducing the ...

We consider the motion of a test particle in a one-dimensional system of equal-mass point particles. The test particle plays the role of a microscopic "piston" that separates two hard-point gases with different concentrations and arbitrary initial velocity distributions. In the homogeneous case when the gases on either side of the piston are in the same macroscopic state, we compute and analyze...

We study the Casimir force in piston-like geometries semiclassically. The force on the piston is finite and physical, but to leading semiclassical approximation depends strongly on the shape of the surrounding cavity. Whereas this force is attractive for pistons in a parallelepiped with flat cylinder head, for which the semiclassical approximation by periodic orbits is exact, this approximation...

In this paper we study the Casimir force for a piston configuration in R 3 with one dimension being slightly curved and the other two infinite. We work for two different cases with this setup. In the first, the piston is " free to move " along a transverse dimension to the curved one and in the other case the piston " moves " along the curved one. We find that the Casimir force has opposite sig...

The concept of a smart skin embodies the philosophy of a multilayer structure that includes sensing elements, actuation elements and a controller. Such an embedded system has been developed for under water vehicle applications where the objective is the control of both near and far field noise. Acoustic/structural characterization is a necessary part of optimal design, however the simulation mo...

Drug delivery through jet-injection opens the doors to very rapid drug dispersion by eliminating the need for needle sterilization. With this comes the need for a continuous flow of fluids from a large reservoir, currently not available to the single-piston drug delivery systems. A two-piston system in a jet injector enables the use of a cyclic motion of pistons to drive the injected fluids, as...

Mass customization manufacturing (MCM) has been gaining recognition as an industrial revolution in the 21st century. This paper presents innovative approaches in realizing and exercising MCM in theoretical and practical applications. Strategies of generalized production line platform and modularization are explored to support dynamic reconfigurations of MCM. NIST’s XML-based Shop Data informati...

This paper presents a new JDtthematieal model of indicated horsepower of rolling piston compressor. It is not an intergul formula but a genertl mathematical formula made out by authors calculating ia detail on the baee of former integral formula of indicated hor1epower aad parameters such as the ratio of Ieath aad diameter, the ratio of eccentric from implicit function. Ia accordance with this ...

− A new controlled-clearance pressure balance has been developed to improve the hydraulic pressure standard for pressures up to 1 GPa. For several controlledclearance piston-cylinders, characterization experiments based on the Heydemann-Welch model were performed to estimate the effective area of them. The results for the piston-cylinders of different pressure ranges are exemplified in this pap...