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...

By theoretically analyzing dynamic behavior of the crankshaft, the rolling piston and the blade inrolling-piston rotary compressors, constraint forces and sliding speed at each pair of movable machine elements were obtained, and unbalanced inertia forces and compressor vibrations were evaluated. It was concluded that theoretical results have a goodagreement with experimental ones. Moreover, it ...

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...

This paper presents the numerical simulation and experimental investigation on impact factors on premature failure of the self-lubricated piston rings in oil-free compressor. In this paper, the finite element method (FEM) was applied to study the non-uniform pressure distributions between the piston rings and the friction process between the self-lubricating piston rings and the cylinder wall, ...

Free-piston diesel engines are characterized by freely moving pistons without any crankshaft or camshaft connected to the pistons. This allows a compact and efficient engine design, but requires automatic control of the piston motion. This paper present a dynamic mathematical model of a free-piston diesel engine, and a control oriented dynamic analysis leading to a piston motion control structu...

Free-piston engines are under investigation by a number of research groups worldwide, as an alternative to conventional technology in applications such as electric and hydraulic power generation. The piston dynamics of the freepiston engine differ significantly from those of conventional engines, and this may influence in-cylinder gas motion, combustion and emissions formation. Due to the compl...

write: A pump has been constructed as a possible solution to a problem posed by one of us (D.W.)-namely, to produce a device which would wash out the bladder after prostatectomy vwithout breaking the closed drainage system (which could result ia an infection) and which could be used by relatively unskilled staff. The pump with its associated valves is composed of only two parts-a piston and a c...

Due to the inherent nature of combustion in the Cylinder of a Conventional Internal combustion engine, stress variation as well as a certain temperature distribution sets up in the entire piston. Analysis of piston is required because of its shape and it is subjected to both structural and thermal loads. In the present study, piston of a two stroke spark ignition internal combustion engine havi...

Piston ring sealing is of great importance in oil-free reciprocating compressors for high pressure application. Pressure distribution and frictional heat on piston rings have been investigated with the aim of finding the key factors influencing the life time of piston rings. A mathematical model simulating the unsteady flow within the gaps of piston rings was established to present the pressure...

The purpose of this paper is to examine the piston stress distribution using several thicknesses of the coating materials to achieve higher gasoline engine performance. First of all, finite element structure analysis is used to uncoated petrol piston made of aluminum alloy. Then, steel and cast iron piston materials are conducted and compared with the aluminum piston. After that, investigation ...