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The analysis carried out in this study can provide guidance for manufacturers and researchers to design a piston for the development of engines.

Running conditions for pistons have become very severe because of the high combustion pressure and increase in piston temperature in the past 10 years. The precision of the model has a great effect on the power transmission, vibration noise emission. In this paper, the model was established with lubrication and dynamic governing equations, which were solved using finite element method coupled with Runge–Kutta method. A piston of an inline six-cylinder engine was studied, and some structural parameters were used to investigate its effect on the friction loss with lubrication and dynamic motion theory.

Based on the analyses, the effect of the friction load at the oil groove and thermal deformation of piston skirt were added to the model, and some useful information about the friction loss and dynamic characteristics were compared.

All the results will provide guidance for the development of the piston and reduction in the friction loss and wear.

This paper aims to study the effect of piston skirt design parameters on the dynamic characteristics of a piston–cylinder contact.

This paper focuses on an analysis of the piston dynamic response. The oil-film pressure and the structural deformation were approximated, respectively, by finite difference method and finite element method.

The results show that the design parameters such as clearance, offset and the axial location of piston pin have a great influence on the dynamics of the piston and hence on the piston slap phenomenon and the frictional power loss.

All the results mainly focus on the slap noise of the engine and can be used in the piston–liner development at the development of the engine.

This paper aims to investigate the effect of lubricant viscosity model with improver on friction and lubrication of piston skirt-cylinder liner conjunction.

A dynamic calculation model is established for the piston skirt-cylinder liner conjunction of a heavy-duty commercial diesel engine, to explore the effects of two kinds of lube oil viscosity models named after polyalkyle-metacrylate-1 (PAMA1) and styrene-isoprene-copolymer (SICP) improvers on the maximum oil film viscosity, the minimum oil film thickness, the peak oil film pressure, the maximum shear rate, the friction force and the total friction power loss.

The variation trends with the crank angle of the above parameters are not changed with the difference of improvers, while obvious numerical differences are found except the maximum oil film pressure. The minimum oil film thickness and maximum shear rate of PAMA1 are larger than that of SICP, the maximum oil film viscosity of SICP is larger than that of PAMA1, which indicates that the shear-thinning effect of PAMA1 is greater, the maximum friction force on the piston of SICP is larger than that of PAMA1, and the total friction power consumption is also larger, the average friction power consumptions of SICP and PAMA1 are 385.4 and 262.8 W, respectively, with the relative difference of 31.8 per cent.

The influence of different lubricating oil additive models on the lubrication and friction of piston skirt-cylinder liner conjunction is simulated and analyzed.

The purpose of this study is to investigate the effects of the axial piston pin motion on the tribological performances of the piston skirt and cylinder liner vibration for an internal combustion engine (ICE) under different operation conditions.

The dynamic equation for the piston incorporating into axial piston pin motion is derived first. Then, the proposed equation and associated lubrication equations are solved using the Broyden algorithm and difference method, respectively. Moreover, the axial motion of the piston pin and its slap on the cylinder liner are studied under different operation conditions.

The axial piston pin motion leads to an overall increase in the friction power consumption. Increments in the ICE speed and lubricant viscosity can augment the axial pin motion and cylinder liner vibration, especially in the power stroke. The said increments cause the instability of the piston motion in the cylinder. The axial motion of piston pin can be restrained through the eccentricity of the piston pin close to the thrust side of the cylinder liner.

This study conducts detailed discussions of the effect of axial piston pin motion on tribological and dynamic performances for piston skirt-cylinder liner system of an internal combustion engine and gives a helpful reference to analyses and designs of internal combustion engines.

The purpose of this paper is to present, for the first time, a mathematical model for a piston skirt in mixed lubrication with respect to applying a smart fluid in lubrication. In this way, the smart fluid, as a lubricant with controlled variable viscosity, is proposed and applied to minimize the power loss in the interaction between liner and skirt.

Based on signal processing, the relationships between viscosity of lubricant and the friction loss, the hydrodynamic and contact friction force consequently are found, as part of an effective approach to acquire the function of variable viscosity.

It is shown that hydrodynamics and contact friction forces can be controlled and minimized by using the variable viscosity signal with the optimized viscosity signal technique.

In this paper, a mathematical model for a piston skirt in mixed lubrication with respect to applying a smart fluid in lubrication is presented for the first time.

This paper aims to understand the influence of cylinder liner temperature on friction power loss of piston skirts and the synergistic effect of cylinder liner temperature on lubrication and heat transfer between piston skirt and cylinder liner.

A method to calculate the influence of cylinder liner temperature on piston skirt lubrication is proposed. The lubrication is calculated by considering the different temperature distribution of the cylinder liner and corresponding piston temperature calculated by a new multilayer thermal resistance model. This model uses the inner surface temperature of the cylinder liner as the starting point, and the starting temperature corresponding to different positions of the piston is calculated using the time integral average. Besides, the transient heat transfer of mixed lubrication is taken into account. Six temperature distribution schemes of cylinder liner are designed.

Six temperature distributions of cylinder liner are designed, and the maximum friction loss is reduced by 34.4% compared with the original engine. The increase in temperature in the second part of the cylinder liner will lead to an increase in friction power loss. The increase of temperature in the third part of the cylinder liner will lead to a decrease in friction power loss. The influence of temperature change in the third part of the cylinder liner on friction power loss is greater than that in the second part.

The influence of different temperature distribution of cylinder liner on the lubrication and friction of piston skirt cylinder liner connection was simulated.

This is a chapter from Mr. Clark's forthcoming book on “Marine Lubrication”, which we shall publish early next year. This book will be the most comprehensive work on this subject ever published and will deal with all aspects of lubrication of marine machinery.

Two papers were presented at a meeting of the Automobile Division in conjunction with the Lubrication Group of the Institution of Mechanical Engineers in London on 10th February, dealing with the lubrication of small 2‐stroke petrol engines. These were as follows:— “Problems Encountered in the Lubrication of small 2‐Stroke Engines,” by A. Towle, M.Sc., M.I.Mech.E., (Lubrizol International Laboratories), and “Influence of the Lubricating Oil on Some Operating Problems of the 2‐Stroke Gasoline Engine.” by D. W. Golothan, A.M.I.Mech.E. (“Shell” Research Ltd.). We give shortened versions of these papers. The Institution of Mechanical Engineers welcome written communications on these papers, which should reach them at 1 Birdcage Walk, Westminster, London, S.W.1., before 30th April. Those wishing to do this can obtain copies of the complete papers from the Secretary of the Institution. The meetings were held at short notice, but in spite of this about 150 members were present and the ensuing discussion showed the importance and interest in this subject.

THE Mercedes‐Benz Model DB‐601A aero‐engine is a development of the Daimler‐Benz Aktiengesellschaft of Stuttgart, Germany, a firm which lias been engaged in the manufacture of automotive and aero‐engines for over fifty years. During the first World War the Daimler Motorcn Gesellschaft of Stuttgart produced the famous Mercedes aero‐engines iii three 6‐cylindcr types with ratings of 160 horse‐power, 180 horse‐power, and 260 horse‐power. Equally renowned were the 160 horse‐power and 230 horse‐power 6‐cylindcr aero‐engines built by Benz and Company in Mannheim. After the war, and as a result of the economic and financial crisis which brought almost complete stagnation to the automotive industry in Germany during the early twenties, these two companies were practically forced to combine their activities in order to survive. Accordingly in 1926 a merger was consummated between the Daimler and Benz organizations. Thus came into being the firm of Daimler‐Benz A.G. and their product, the Mercedes‐Benz line of automotive vehicles and aircraft power plants.

A computer simulation which as model loads uses program KIVA 3 for combustion engine work process (combustion chamber heat flux, pressure and temperature) computations has been developed. It makes it possible to compute the pressure and temperature distributions and the motion of the charge in the combustion chamber at a particular point in the work cycle. Computer models of the ring seal components were constructed using computer code Parasolid v. 11. The models render to the finest detail the design‐material features of the ring seal components. The Nastran program was used to perform FEM computations for a selected point of engine work (at a crank angle of 10°) at which the maximum averaged temperatures and pressures were found to occur in the combustion chamber. Finally, 3D temperature and pressure distributions for the whole ring seal were obtained. On their basis, inferences can be made about the design‐technological nature of the seal under development.