Gas escape to crankcase: impact of system parameters on sealing behavior of a piston cylinder ring pack

The oil consumption and blow-by gas through piston-cylinder-ring crevices have to be minimized. Meanwhile, the friction losses in the piston ring pack need to be reduced in order to improve fuel economy and engine performance. In these two aspects, study on the optimized design of the piston ring pack has to be carried out. The amounts of oil consumption and blow-by gas are important factors to decide whether an engine is operating under good conditions or not during engine development and engine life cycle. The purpose of this study is to develop a computer program predicting engine oil consumption and blow-by gas by calculating the amount of oil flowing into the combustion chamber and gas flow down to the crankcase through the piston ring pack. Using this program, the condition of an engine can be predicted in advance.

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Models of Cataclysmic Variables from Photometric and Spectroscopic Data

International Astronomical Union Colloquium ◽

10.1017/s0252921100073292 ◽

1979 ◽

Vol 46 ◽

pp. 65-74 ◽

Cited By ~ 1

Author(s):

A.C. Fabian ◽

J.E. Pringle ◽

J.A.J. Whelan ◽

J.A. Bailey

Keyword(s):

Spectroscopic Data ◽

Cataclysmic Variables ◽

System Parameters ◽

Dwarf Nova ◽

Spectroscopic Observations ◽

Photometric And Spectroscopic Observations

Abstract.Recent photometric and spectroscopic observations of the dwarf nova system Z Cha are discussed. Methods for constraining the system parameters are applied and the disc emissivity is deduced as a function of radius. Indications are found that the disc shrinks in size with increasing time after outburst.

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Review for "Laboratory‐scale simulation of industrial neutral electrolytic pickling as a bipolar system—Parameters affecting indirect polarization pickling of annealed stainless steel"

10.1002/eng2.12245/v2/review1 ◽

2020 ◽

Keyword(s):

Stainless Steel ◽

Laboratory Scale ◽

System Parameters ◽

Electrolytic Pickling

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Decision letter for "Laboratory‐scale simulation of industrial neutral electrolytic pickling as a bipolar system—Parameters affecting indirect polarization pickling of annealed stainless steel"

10.1002/eng2.12245/v1/decision1 ◽

2020 ◽

Keyword(s):

Stainless Steel ◽

Laboratory Scale ◽

System Parameters ◽

Electrolytic Pickling

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Some Factors Influencing Metabolism and Distribution of Fibrinogen in Man and Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649225 ◽

1977 ◽

Vol 37 (02) ◽

pp. 243-252

Author(s):

Yi-Hsiang Chen ◽

E. B Reeve

Keyword(s):

Plasma Fibrinogen ◽

Synthesis Rate ◽

Fibrinogen Concentration ◽

Fractional Catabolic Rate ◽

System Parameters ◽

Catabolic Rate ◽

Simultaneous Decrease ◽

Normal Males ◽

Healthy Females ◽

Made In

SummaryTo shed some light on the homeostatic regulation of plasma fibrinogen, metabolic studies were made in healthy females, and in normal, thyroidectomized, and thyroxine-treated rabbits. In females, compared with normal males, plasma fibrinogen concentration, plasma and interstitial fibrinogen decreased consequent to an increased fractional catabolic rate and a normal fibrinogen synthesis rate. The interstitial/plasma fibrinogen ratio remained unchanged. In normal rabbits, with increasing body weight fractional catabolic rate and catabolic rate decreased, while fibrinogen concentration and plasma fibrinogen remained constant owing to a simultaneous decrease in fibrinogen synthesis. In addition, fractional transcapillary transfer rate and transcapillary flux also decreased resulting in a shrinkage of interstitial fibrinogen. Thyroidectomy and thyroxine-injection markedly altered fibrinogen metabolism: thyroid hormone accelerated fibrinogen catabolism but also stimulated synthesis. The net result was an increase in plasma fibrinogen and fibrinogen concentration. The interstitial/plasma fibrinogen ratio decreased in thyroxine-treated, and increased in thyroidectomized animals. This study defines the variations of the fibrinogen system parameters in these physiologic and pathologic conditions, and illustrates some patterns of alterations in fibrinogen metabolism.

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THE ELECTROMAGNETIC FIELDS EFFECT ON CHAOTIC DYNAMICS OF CARDIOVASCULAR SYSTEM PARAMETERS OF WORKERS OF OIL AND GAS INDUSTRY

Human Ecology ◽

10.33396/1728-0869-2017-8-3-7 ◽

2017 ◽

pp. 3-7 ◽

Cited By ~ 5

Author(s):

А. V. Boltaev ◽

G. V. Gazya ◽

А. А. Khadartsev ◽

D. V. Sinenko

Keyword(s):

Cardiovascular System ◽

Electromagnetic Fields ◽

Chaotic Dynamics ◽

Oil And Gas ◽

Oil And Gas Industry ◽

Gas Industry ◽

System Parameters

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Predictive tool for frictional performance of piston ring-pack/liner conjunction

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.13.3.2019.19.0445 ◽

2019 ◽

Vol 13 (3) ◽

pp. 5513-5527

Author(s):

J. W. Tee ◽

S. H. Hamdan ◽

W. W. F. Chong

Keyword(s):

Film Thickness ◽

Mathematical Models ◽

Piston Ring ◽

Published Data ◽

Predictive Tool ◽

Frictional Losses ◽

Fundamental Understanding ◽

Minimum Film Thickness ◽

Piston Ring Pack ◽

Ring Pack

Fundamental understanding of piston ring-pack lubrication is essential in reducing engine friction. This is because a substantial portion of engine frictional losses come from piston-ring assembly. Hence, this study investigates the tribological impact of different piston ring profiles towards engine in-cylinder friction. Mathematical models are derived from Reynolds equation by using Reynolds’ boundary conditions to generate the contact pressure distribution along the complete piston ring-pack/liner conjunction. The predicted minimum film thickness is then used to predict the friction generated between the piston ring-pack and the engine cylinder liner. The engine in-cylinder friction is predicted using Greenwood and Williamson’s rough surface contact model. The model considers both the boundary friction and the viscous friction components. These mathematical models are integrated to simulate the total engine in-cylinder friction originating from the studied piston ring-pack for a complete engine cycle. The predicted minimum film thickness and frictional properties from the current models are shown to correlate reasonably with the published data. Hence, the proposed mathematical approach prepares a simplistic platform in predicting frictional losses of piston ring-pack/liner conjunction, allowing for an improved fundamental understanding of the parasitic losses in an internal combustion engine.

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