Break-In Liner Wear and Piston Ring Assembly Friction in a Spark-Ignited Engine

Even though many researchers have measured the piston/ring assembly friction force over the last several decades, accurate measurement of the piston/ring assembly friction force is a still challenging problem. The floating liner method is not widely used, in spite of its accuracy, due to the substantial modifications required to the engine. On the other extreme, bench tests of the piston/ring assembly cannot completely simulate the real firing condition although bench tests are rapid, consistent, and cost effective. In this study, friction forces of the piston/ring assembly were measured using the instantaneous IMEP method and compared with modeling results using Ricardo’s RINGPAK software. In this research, a flexible flat cable was used to connect the connecting rod strain gage signal to the analysis system instead of using a grasshopper linkage. Therefore, the piston/ring assembly friction force was measured with the minimum change to the engine hardware.

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Measurement of Piston and Piston Ring Assembly Friction Force

10.4271/851671 ◽

1985 ◽

Cited By ~ 6

Author(s):

Takaharu Goto ◽

Shun-ichi Aoyama ◽

Shin-ichi Nagumo ◽

Yasuo Nakajima ◽

Michio Onoda

Keyword(s):

Friction Force ◽

Piston Ring ◽

Ring Assembly

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An analytical study of tribological parameters between piston ring and cylinder liner in internal combustion engines

Proceedings of the Institution of Mechanical Engineers Part K Journal of Multi-body Dynamics ◽

10.1177/1464419315605922 ◽

2016 ◽

Vol 230 (4) ◽

pp. 329-349 ◽

Cited By ~ 8

Author(s):

Mohamed Kamal Ahmed Ali ◽

Hou Xianjun ◽

Richard Fiifi Turkson ◽

Muhammad Ezzat

Keyword(s):

Film Thickness ◽

Internal Combustion Engines ◽

Piston Ring ◽

Cylinder Liner ◽

Combustion Engines ◽

Oil Viscosity ◽

Oil Film ◽

Ring Assembly ◽

Ring Dynamics ◽

Tribological Parameters

This paper presents a model to study the effect of piston ring dynamics on basic tribological parameters that affect the performance of internal combustion engines by using dynamics analysis software (AVL Excite Designer). The paramount tribological parameters include friction force, frictional power losses, and oil film thickness of piston ring assembly. The piston and rings assembly is one of the highest mechanically loaded components in engines. Relevant literature reports that the piston ring assembly accounts for 40% to 50% of the frictional losses, making it imperative for the piston ring dynamics to be understood thoroughly. This analytical study of the piston ring dynamics describes the significant correlation between the tribological parameters of piston and rings assembly and the performance of engines. The model was able to predict the effects of engine speed and oil viscosity on asperity and hydrodynamic friction forces, power losses, oil film thickness and lube oil consumption. This model of mixed film lubrication of piston rings is based on the hydrodynamic action described by Reynolds equation and dry contact action as described by the Greenwood–Tripp rough surface asperity contact model. The results in the current analysis demonstrated that engine speed and oil viscosity had a remarkable effect on oil film thickness and hydrodynamic friction between the rings and cylinder liner. Hence, the mixed lubrication model, which unifies the lubricant flow under different ring–liner gaps, is needed via the balance between the hydrodynamic and boundary lubrication modes to obtain minimum friction between rings and liner and to ultimately help in improving the performance of engines.

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FRICTIONAL POWER MINIMIZATION IN PARTIALLY TEXTURED PISTON RING ASSEMBLY

International Journal of Mechanical and Industrial Engineering ◽

10.47893/ijmie.2013.1142 ◽

2013 ◽

pp. 132-136

Author(s):

AARON. M. ASHWIN ◽

AKASH SASHIDHAR

Keyword(s):

Piston Ring ◽

Surface Texturing ◽

Laser Surface Texturing ◽

Total Power ◽

Exhaust Pipe ◽

Power Losses ◽

Automotive Engine ◽

Frictional Losses ◽

Ring Assembly ◽

Brake Power

A significant share i.e. 60% of the total power loss in a modern automotive engine in form of heat, either from the engine surface or the exhaust pipe, of which the friction losses may vary from 18% to 20% and frictional losses are also responsible for about 25% of the fuel consumption. It is noted that almost 80% of the frictional losses are due to the frictional losses in the piston ring assembly (PRA). That leaves less than one quarter of the indicated power in terms of brake power. This paper analyses different methods developed by the automobile industries in order to reduce the friction power losses it may be in form of the development of better lubricants, design and partial laser surface texturing (LST) of the piston rings.

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Theoretical Modeling and Simulation of Piston Ring Assembly of an IC Engine

ASME/STLE 2004 International Joint Tribology Conference, Parts A and B ◽

10.1115/trib2004-64191 ◽

2004 ◽

Cited By ~ 2

Author(s):

Kishore Mistry ◽

D. V. Bhatt ◽

N. R. Sheth

Keyword(s):

Friction Force ◽

Piston Ring ◽

Hydrodynamic Lubrication ◽

Cylinder Liner ◽

Lubrication System ◽

Ic Engine ◽

Frictional Loss ◽

Frictional Losses ◽

Ring Assembly ◽

Ring Geometry

Frictional losses in an IC engine are observed between 17–19% of total induced horsepower. 35–45% frictional losses observed due to piston ring assembly only from the above-referred total frictional loss. Lubrication system is for reducing the frictional losses and under the total hydrodynamic lubrication system, if made it feasible, above referred losses can be reduced considerably. Wear normally observed at TDC and BDC during the power stroke. Experimental set-up is prepared by using used piston-cylinder assembly of an engine. Experiment methodology is adopted based on certain assumption and simulated the entire system with an extra drive system by an electric motor with a provision of various speed availability. Various pockets on cylinder liner of 2mm diameter are located on the periphery of cylinder liner to offer lubrication to the system. Care was taken to control the rate of lubrication flow with the help of control knob. Seven different profiles on piston ring were generated and measured. Friction force is calculated by power consumption measurement under different dynamic condition with a variation of 5-speed, 3- lubricants and different 8- types of piston ring geometry are experimented under different combination and results are tabulated. Graphs are plotted for friction force v/s speed for different lubricants and piston ring profiles. Effect of lubricants (SAE30, 15W40& 2T) and ring geometry are compared.

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