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The purpose of this paper is to analyze the micro-motion of the cylinder block.

Based on the elasto-hydrodynamic lubrication, a numerical model for the cylinder block/valve plate interface is proposed, with consideration of the elastic deformations, the pressure-viscosity effect and asperity contacts. The influence-function method is applied to calculating the actual deformations of the cylinder block and the valve plate. The asperity contact model simplified from Greenwood assumption is introduced into the numerical model. Furthermore, the relationship between the micro-motion and the operating condition, the sealing belt width is discussed, respectively.

The results show an increase in the discharge pressure causes the tilt state and the vibrating motion getting worse, which can be eased by improving the rotational speed, the sealing belt width and the ratio of external and internal sealing belt width.

The proposed research can provide a theoretical reference for the optimizing design of cylinder block/valve plate pair.

The purpose of this study was to develop a new approach using a pulse YAG laser with rational power density and pulse width to texture desired discrete distribution morphology on the cylinder wall.

Variational rules of the effects of these three parameters were found by calculating the oil film on the cylinder/piston ring system. The experiment results were compared between laser texturing cylinders and conventional honing cylinders.

It was found that the coefficient of friction and wear rate of laser texturing cylinders were reduced by 50 and 85.7 per cent, respectively, and the piston ring wear rate was decreased by 50 per cent under full lubrication condition. Under starved lubrication condition, the cylinder liner wear was reduced by 34.3 per cent.

The effectiveness of which was determined by three control parameters: depth-to-diameter ratio, area density and distribution angle of the dimples.

High pressure and high speed of the axial piston pump can improve its power density, but they also deteriorate the thermal-fluid-structure coupling effect of the friction pairs. This paper aims to reveal the coupling mechanism of the pump, for example, valve plate pair, by carrying out research on multi-physics field coupling.

Considering the influences of temperature on material properties and thermal fluid on structure, the thermal-fluid elastic mechanics model is established. A complete set of fast and effective thermal-fluid-structure coupling method is presented, by which the numerical analysis is conducted for the valve plate pair.

According to calculations, it is revealed that the temperature and pressure evolution laws of oil film with time, the pressure distribution law of the fluid, stress and displacement distribution laws of the solid in the valve plate pair. In addition, the forming history of the wedge-shaped oil film and mating clearance change law with rotational speed and outlet pressure in the valve plate pair are presented.

For an axial piston pump operating under high speed, high pressure and wide temperature range, the multi-physics field coupling analysis is an indispensable means and method. This paper provides theoretical evidence for the development of the pump and lays a solid foundation for the research of the same kind of problem.

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.

The aim of the research work presented here is to control the geometric distortions of engine cylinders, which involve both noise and oil consumption. The final goal is then to limit pollution from engines. The simulation deals initially with the cold stamping and crushing operations of a cylinder head gasket; based on using solid finite element models from the Abaqus computer code (version 5.3) for large deformation with plasticity and contact, including friction. In addition, experiments have been carried out to identify the plasticity rule for the materials used in order to simulate the crushing of the cylinder head gasket under a given normal pressure representing the clamping operation. The main difficulty of this work is to correlate the cylinder head gasket behaviour and cylinder distortions with the main function of the gasket, i.e. pressurized gas sealing. The cylinder head gasket is a complex multilayered structure made of three spot welded metal sheets. This assembly has many holes of different shapes. Around the cylinder hole on both outer layers of the gasket, there is a small size embossment to ensure gas sealing between the engine block and cylinder head. This rib is not circular because of the combustion chamber shape.

Fiat is to achieve 80% automation in assembly of its new FIRE 1000 engine in a plant built for it by Comau to turn out 21,000 engines a day.

The robotized cylinder head and engine assembly lines at the Opel car factory in Kaiserslautern, Germany, make it one of the most advanced of its kind in the world. Designed and installed by ABB as a turnkey system, the project has set new standards for logistics, floor‐space requirements, economy and productivity. Zero‐defect production was given the highest priority during planning and realization of the assembly lines. Robot stations, special‐purpose machines and manual workstations have been combined in a way that optimizes the plant configuration and achieves maximum benefit for the plant operators.

An assembly of an internal combustion motor together with its cooling and ventilating equipment all faired within the normal contour of an aeroplane wing in such a way that no projections extend therefrom, comprising a fuselage, a wing, means to form a motor compartment bounded on its upper side by a portion of the upper surface of the wing next to the fuselage, said motor compartment being bounded on its lower side by a portion of the lower surface of the wing, a hatch removably separating said motor compartment from the fuselage, louvers formed in a portion of the lower surface of the wing that also forms the lower wall of said motor compartment, said louvers being arranged to draw air downward out of the compartment when the aero‐plane is in normal horizontal flight, whereby fumes that may escape from the motor may bo drawn away from the fuselage and whereby any movement of air past said hatch may be toward the louvers, an intake connexion for cooling air in the bottom wall of the compartment, a casing extending from said intake opening and extending to and enclosing the combustion‐chamber portion of the motor, said casing also extending from said enclosing portion toward the trailing edge of the wing to an opening in the top surface of the wing, and an exhaust con‐nexion extending from said combustion‐chamber portion of the motor to said opening in the top surface of the wing.

This paper aims to carry out a thermal-hydraulic simulation model for pump and hydraulic system to predict the temperature increasing and pump performance. Based on the model, how to alleviate the temperature is introduced. Besides, the optimization of piston is carried out.

This paper analyzes the heat generation in lubricating interfaces of the pump with energy conversion theory. The heat transfer inside the pump is analyzed with the control volume method. The simulation model is constructed in AMESim because of its operating friendly nature. The experiment is carried out to prove the validity and accuracy of the simulation model.

Temperature has less effect on the mechanical loss of pump. However, it has a great impact on volumetric efficiency. To reduce the temperature on the piston surface, the size of the piston should be optimized.

This paper fulfills a novel thermal-hydraulic model to evaluate the temperature of the pump. Based on the model, the performance of the pump is determined and optimization is carried out.

Many forms of corrosion can be present in the cooling system of a motor‐car, in which a hot coolant, often unsuitable from the point of view of corrosion, flows through a number of parts made of different metals. Attack is aggravated by such conditions as exhaust gas or air leakage into the system. Corrosion can be minimised by the use of effective inhibitors. The first article in this series, ‘Corrosive Wear of Piston Rings and Cylinders,’ appeared in the August issue of CORROSION TECHNOLOGY.