Measurement of friction and noise from piston assembly of a single-cylinder motorbike engine at realistic speeds

2017 ◽  
Vol 232 (13) ◽  
pp. 1715-1735 ◽  
Author(s):  
Anastasios Zavos ◽  
Pantelis G Nikolakopoulos
Keyword(s):  
Strain Gauge ◽  
Piston Ring ◽  
Calibration Procedure ◽  
Operating Conditions ◽  
Power Stroke ◽  
Cylinder Wall ◽  
Single Cylinder ◽  
Noise Data ◽  
Cylinder Bore ◽  
Piston Assembly

This paper presents a thorough experimental study of piston assembly friction and noise in a single-cylinder motorbike engine operating at low speeds. The friction of the piston ring pack is evaluated using a foil strain gauge with minimal cylinder modification on the thrust side. The technique involves transmitting deformations through the cylinder bore and recording reflections from the lubricated interface as the piston assembly passes. Under these conditions, the piston side forces and the thermal deformations on the output side of the strain gauge sensor are critical. Therefore, the proposed methodology is designed under controlled operating conditions. The overall deformation of the piston assembly is analysed to measure the primary reflection due to friction between the piston assembly and the cylinder wall. Simultaneously, the piston assembly noise is recorded on the thrust side of the engine block using a microphone. Taking measured noise data into account, possible piston slap events resulting from varied engine speeds are taken into account using continuous wavelet signal analysis. The calibration procedure for both tests is also illustrated. The measured friction results show that the strain gauge technique is a challenging work in providing realistic results to enhance current technology. For low engine speeds, a higher contribution is noted by boundary friction at the top dead centre reversal, extending to the position of maximum combustion pressure in the power stroke. Furthermore, the main contribution of the piston slap is estimated at the thrust side when the piston assembly passes at the beginning of the combustion stroke. These results can also be attributed as data to validate piston ring models in terms of friction and piston slap.

A Spectrographic Sampling Method for Quick Assessment of Cylinder and Piston Ring Wear

1968 ◽  
Vol 90 (1) ◽  
pp. 43-48
Author(s):  
H. U. Wisniowski ◽  
D. R. Jackson
Keyword(s):  
Rapid Method ◽  
Sampling Method ◽  
Piston Ring ◽  
Cylinder Liner ◽  
Small Sample ◽  
Operating Conditions ◽  
Small Hole ◽  
Cylinder Wall ◽  
Lubricating Oils ◽  
Wear Rates

A simple, inexpensive, and rapid method of assessing cylinder and piston ring wear was developed. A small sample of the oil which lubricates the cylinder wall and piston rings was drawn off through a small hole in the cylinder wall. The sample was then analyzed spectrographically. Changes in wear resulting from changes in cylinder liner materials, fuels, lubricating oils, and other operating conditions were investigated. The method was found useful especially in cases of drastic differences in the wear rates. Selected examples of these studies are reported.

Numerical Investigation of the Effects of Axial Cylinder Bore Profiles on Piston Ring Radial Dynamics

2003 ◽  
Vol 125 (4) ◽  
pp. 1081-1089 ◽  
Author(s):  
Y. Piao ◽  
S. D. Gulwadi
Keyword(s):  
High Speed ◽  
Piston Ring ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Operating Conditions ◽  
Engine Oil ◽  
Oil Consumption ◽  
Ring Pack ◽  
Cylinder Bore

The role of cylinder bore shapes in engine performance has been the subject of several studies in recent years. In particular, the influence of bore distortion on oil consumption under high speed conditions has generated significant interest. In this paper, the effect of an axial bore profile on radial dynamics of a ring is investigated. Radial ring motions within grooves due to the axial bore profile can generate significant inertial effects and also have an impact on ring end-gap sizes and lubrication conditions at the ring-liner interfaces. The magnitude of such effects is dependent on the ring-pack configuration, engine operating conditions (speed and load) and axial bore profile details. These issues are investigated in this study due to their implication on engine oil consumption, friction and blow-by. The authors have developed an analytical expression to account for the effects of radial ring inertia due to an axial bore profile for implementation in a piston ring-pack simulation tool RINGPAK. Simulation results from a gasoline engine study are presented to illustrate the effects of engine speeds, ring tensions, and characteristics of axial bore profiles on ring radial dynamics and ring-liner lubrication. Relevant qualitative comparisons are made to experimental measurements available in the literature.

An Investigation of the Sources of Blowby in Single-Cylinder Supercharged Diesel Engines

1978 ◽  
Vol 192 (1) ◽  
pp. 39-48 ◽  
Author(s):  
B. Bull ◽  
M. A. Voisey
Keyword(s):  
Carbon Dioxide ◽  
Diesel Engines ◽  
Piston Ring ◽  
Carbon Dioxide Concentration ◽  
Operating Conditions ◽  
Exhaust Valve ◽  
Simple Method ◽  
Single Cylinder ◽  
Carbon Dioxide Concentrations ◽  
Wide Range

Measurements of carbon dioxide concentrations in the exhaust and in the crankcase of two different types of single-cylinder, supercharged diesel engines have been used to determine the amount of exhaust gas reaching the crankcase as piston ring blowby and as leakage through the exhaust valve stem-to-guide clearance. Over a wide range of operating conditions in both engines the carbon dioxide concentration was found to be more dependent on engine fuelling rate per hour than on fuel input per stroke. It was established that blowby through the exhaust valve guide was a major contributor to crankcase contamination. A simple method has been devised, requiring only minor modifications to the engine, that permits the blowby through the piston ring pack and the exhaust valve guides to be determined separately in turbocharged production engines.

Lubricant Degradation Studies Using a Single Cylinder Research Engine

2005 ◽  
Author(s):  
P. M. Lee ◽  
M. Priest ◽  
M. S. Stark ◽  
J. J. Wilkinson ◽  
J. R. Lindsay Smith ◽  
...  
Keyword(s):  
Fuel Consumption ◽  
Tribological Performance ◽  
Operating Conditions ◽  
Engine Oil ◽  
Oil Degradation ◽  
Lubricant Degradation ◽  
Reduce Fuel Consumption ◽  
Single Cylinder ◽  
Degradation Studies ◽  
Piston Assembly

With increasing pressure on engine oil manufacturers to extend oil drain intervals and reduce fuel consumption, whilst changing the composition of fully formulated oils to meet new CEC, ILSAC and OEM specifications, there is ever increasing need to understand the effect of oil degradation on the operating conditions and tribological performance of engines. This poster presents mechanical changes made to a single cylinder research engine to enable the study of lubricant degradation, its transport and how this links to piston assembly tribology. A summary of the research undertaken using these changes and a sample of results obtained to date are also presented.

Adaptronic Form Honing – Manufacturing Methods for Compensating Cylinder Bore Distortions

2014 ◽  
Vol 907 ◽  
pp. 489-499
Author(s):  
Reimund Neugebauer ◽  
Carsten Hochmuth ◽  
René Schneider
Keyword(s):  
Piston Ring ◽  
Combustion Engine ◽  
Surface Profile ◽  
Operating Conditions ◽  
Friction Reduction ◽  
Free Form ◽  
Shape Accuracy ◽  
Manufacturing Method ◽  
Tribological System ◽  
Cylinder Bore

Cylinder bore finishing requirements are defined by quality features such as roundness and cylindricity as well as by the manifestation of the surface profile. Honing is a proven manufacturing method s to achieve this. Undesirable distortions of the cylinder shape occur under operating conditions in a reciprocating internal combustion engine. These negatively affect the tribological system of piston, piston ring, and cylinder bore. As a result, efficiency deteriorates and oil consumption rises. The cylinder crank cases are finished in a defined tensioned state to compensate for distortions. This results in a highly complex manufacturing process and is only suited for compensating static distortions. Further increasing machining requirements resulting from strategies such as lightweight construction, downsizing, and friction reduction are pushing conventional honing methods to their technological limits.Adaptronic form honing constitutes a production engineering approach to manufacturing a free form in the cylinder bore. The objective is to keep inverse distortion geometries in store as macro shapes. These will then represent ideal cylinder shapes under the influence of distortion mechanisms in a defined engine operating range. Tool and process development and the analysis of machining results with respect to productivity, shape accuracy, and surface topography are presented and viewed as potential options for optimizing the tribological system of piston, piston ring, and cylinder bore. Other options such as shortening the process chain will be derived.

Numerical Investigation of the Effects of Axial Cylinder Bore Profiles on Piston Ring Radial Dynamics

2002 ◽  
Author(s):  
Y. Piao ◽  
S. D. Gulwadi
Keyword(s):  
High Speed ◽  
Piston Ring ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Operating Conditions ◽  
Engine Oil ◽  
Oil Consumption ◽  
Ring Pack ◽  
Cylinder Bore

The role of cylinder bore shapes in engine performance has been the subject of several studies in recent years. In particular, the influence of bore distortion on oil consumption under high speed conditions has generated significant interest. In this paper, the effect of an axial bore profile on radial dynamics of a ring is investigated. Radial ring motions within grooves due to the axial bore profile can generate significant inertial effects and also have an impact on ring end-gap sizes and lubrication conditions at the ring-liner interfaces. The magnitude of such effects is dependent on the ring-pack configuration, engine operating conditions (speed and load) and axial bore profile details. These issues are investigated in this study due to their implication on engine oil consumption, friction and blow-by. The authors have developed an analytical expression to account for the effects of radial ring inertia due to an axial bore profile for implementation in a piston ring–pack simulation tool RINGPAK. Simulation results from a gasoline engine study are presented to illustrate the effects of engine speeds, ring tensions and characteristics of axial bore profiles on ring radial dynamics and ring-liner lubrication. Relevant qualitative comparisons are made to experimental measurements available in the literature.

A Study on a Rotational Force Acting on the Piston Ring of a Gasoline Engine

2019 ◽  
Author(s):  
Kenta Tomizawa ◽  
Akemi Ito
Keyword(s):  
Piston Ring ◽  
Gasoline Engine ◽  
Periodic Wave ◽  
Operating Conditions ◽  
Wave Form ◽  
Oil Consumption ◽  
Rotational Force ◽  
Oil Transport ◽  
Ring Rotation ◽  
Cylinder Bore

Abstract Oil consumption of an engine causes particulate matter, poisoning catalysts and sometimes abnormal combustion like pre-ignition. One of the factors of oil consumption is oil transport via a piston ring-gap. Coincident of ring-gaps at a same position may cause an increase in oil consumption. In this research, the effect of coincident the ring gaps on oil consumption was measured using with/without the a stopper pin for the ring rotation by sulfur tracer method. A lot of spikes was found in the wave form of sulfur concentrate for the rings without the stopper pin, and higher value of oil consumption was simultaneously measured. Then the force which caused ring rotation (hereafter ‘rotational force’) was measured by a newly developed method. A cantilever was installed in the ring gap, and the strain gauges were pasted on the cantilever. Therefore, the rotational force was measured as the bending stress of the cantilever. It was found that the rotational force showed a periodic wave form against the crank angle. Furthermore, it was also found that the amplitude of the rotational force was strong affected by the engine operating conditions. The rotational force was also affected by the gap position. It was assumed that not only the piston lateral motion but also the cylinder bore shape affected the rotational force. The mechanism of generating the rotational force is the future subject.

scholarly journals The compression ring profile influence on hydrodynamic performance of the lubricant in diesel engine

2020 ◽  
Vol 12 (6) ◽  
pp. 168781402093084
Author(s):  
Brahim Menacer ◽  
Mostefa Bouchetara
Keyword(s):  
Diesel Engine ◽  
Film Thickness ◽  
Piston Ring ◽  
Hydrodynamic Lubrication ◽  
Operating Conditions ◽  
Hydrodynamic Performance ◽  
Cylinder Wall ◽  
Power Losses ◽  
Oil Film ◽  
Compression Ring

For different operating conditions of an internal combustion engine, the piston–ring–liner compartment represents one of the largest sources of friction and power losses. The aim of this article is to evaluate the effect of the compression ring profile on the main tribological performance of the lubricant in a four-stroke diesel engine. A one-dimensional analysis was developed for the hydrodynamic lubrication between the compression piston ring and the cylinder wall. A numerical method was applied to analyze the influence of different ring geometrical designs during the working cycle on oil film thickness, frictional force, and power losses. Our predicted results were validated with the Takiguchi data of a previous study, and they have shown a good agreement. The results in the current analysis demonstrated that the ring geometry profile, the engine speed, and load have a remarkable effect on oil film thickness, friction force, and friction power losses between the top ring and cylinder liner. Therefore, it would help in reducing friction as well as making a contribution to the improvement of engine performance such as torque, efficiency, and fuel consumption.

On the lubrication characteristics of piston ring under different engine operation conditions

2019 ◽  
Vol 72 (1) ◽  
pp. 101-108
Author(s):  
Jun Sun ◽  
Xiao Zhang ◽  
Jianxiong Zhu ◽  
Yaming Gao ◽  
Hu Wang ◽  
...  
Keyword(s):  
Piston Ring ◽  
Cylinder Liner ◽  
Operating Conditions ◽  
Lubricating Oil ◽  
Cylinder Wall ◽  
Engine Operation ◽  
Operating Condition ◽  
Content Type ◽  
Lubrication Characteristics ◽  
Stroke Engine

Purpose Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always operate in rated operating condition, and its operating condition changes frequently in actual use. In addition, the lubrication status of piston ring is generally assumed as the flooded lubrication or a certain form of poor lubrication in most of the lubrication analysis. Design/methodology/approach In this paper, based on the equations about the flow rate of lubricating oil and the variation of control volume, the flow model of lubricating oil in the piston ring-cylinder liner conjunction is established. The lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done, in which the lubricating oil at the inlet of piston ring is considered as the lubricating oil attached on the relevant location of cylinder wall after the piston ring moves over at the previous stroke. Findings There is remarkable difference for the lubrication characteristics of the piston ring under different engine operating conditions. The worst lubrication status of piston ring may not take place under engine rated operating condition. Originality/value In this paper, based on the measured engine cylinder pressure, the lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done in which the lubricating oil supply condition at the inlet of piston ring is considered. The results of this paper are helpful for the design and research of engine piston ring-cylinder liner conjunction.

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