A model for drag forces in the crevice of pneumatic piston gauges is presented. The model uses an interpolation function for momentum transfer between the piston and the cylinder mediated by the gas flowing in the crevice. The interpolation function bridges the gap between the molecular-flow and viscous-flow regimes, and is then used to develop an expression for the effective area of a piston g...

The component piston in an internal combustion engine plays an important role in transforming the thermal energy developed during the combustion in to mechanical energy. During this process, the piston is subject to heat, and pressures developed in the combustion as well as variations in pressures during various strokes of the engine. Hence, there is a need to study the behavior of the piston t...

OBJECTIVE The aim of this study was to compare the results of application of 2 types of superelastic nitinol prostheses. STUDY DESIGN Temporal bones study with planned data collection. SETTING Tertiary referral center. SUBJECTS AND METHODS Malleostapedotomy was performed in 15 human temporal bones implanting 3 different prostheses: manually crimping polytetrafluoroethylene (MC-PTFE) pisto...

One of the main sources of efficiency loss in heat engines is the inability of a sinusoidally displaced piston engines to approximate the ideal heat volumetric cycles the engines require. While attempts have been made to address this issue in the past, recent developments in Stirling engine technology utilizing rolling diaphragm seals on the cylinders has offered an opportunity to greatly incre...

Tris paper, through analy3is to the specific power of the compressor, indicates that to reduce the power loss caused by friction is an important way to reduce the specific power of the compressor, investigates the realizability employing a single piston ring or a piston ring with small elasticity in the high speed double acting compressor, and raises a standpoint for a high speed double acting ...

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 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...

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 ...