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

In the automobile industry, the mechanical losses resulting from friction are largely responsible for various kinds of surface damage, such as the scuffing occurring in some mechanical assemblies. These scuffing processes seem to be due to a local loss of lubrication between certain mechanical elements of the same assembly, leading to a sharp increase in the friction, which can lead to a surfac...

Pressure and performance requirements of axial piston pumps and the proportion of churning losses in axial piston pumps increase significantly with increasing speed. To investigate the primary distribution of churning losses in axial piston pumps at various ranges of speed, a test rig was set up in which other friction losses can be eliminated, thus making it possible to investigate the net chu...

The piston performance affects the performance of the Motorcycle. In order to forecast the piston performance effectively, the performance forecast model based on BP neural network is presented. According to the characteristics of piston performance, the training samples are made up of the orthogonal experimental data, which are utilized to ensure higher generalization of BP neural network. And...

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, ...

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...

A novel scuffing methodology was developed utilising variable specimen geometry to replicate numerically modelled top compression ring contact pressures (4–62 MPa) from a 12.8-litre heavy duty diesel engine as function of stroke position. Scuffing grade 250 cast iron induced by reciprocating sliding (TE77) against drip lubricated (PAO4) 52100 rectangular operating at 15 Hz and 311 N normal load...