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...

A new engine block with optical access has been designed and manufactured capable of running up to 3000 r/min the same specification as unmodified engine. The window allowed full length liner over a width 25 mm investigate lubricant flow cavitation at contact point between rings cylinder-liner. In addition, it good into combustion chamber allow charged flow, spray visualisation measurements usi...

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 ...