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Article
Publication date: 8 January 2018

Fanming Meng, Minggang Du, Xianfu Wang, Yuanpei Chen and Qing Zhang

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 14 March 2016

Ridha Mazouzi, Ahmed Kellaci and Abdelkader Karas

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

Abstract

Purpose

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

Design/methodology/pproach

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.

Findings

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.

Originality/value

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.

Details

Industrial Lubrication and Tribology, vol. 68 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 September 2019

Bora Lee, Yonghun Yu and Yong-Joo Cho

This paper aims to provide a reliable and efficient numerical piston–cylinder design method and assess the effect of clearance on the piston-cylinder lubrication.

Abstract

Purpose

This paper aims to provide a reliable and efficient numerical piston–cylinder design method and assess the effect of clearance on the piston-cylinder lubrication.

Design/methodology/approach

Numerical analyses of lubrication characteristics were performed for the piston–cylinder interface. The axial piston was numerically modeled, and the film pressure was calculated using the unsteady two-dimensional Reynolds equation. The behavior of the piston was analyzed by calculating the eccentricity satisfying the force and moment balance.

Findings

The secondary motion of the piston included numerically simulated several cycles until the piston behavior converged, and contact with the inner wall of the cylinder and friction region was estimated. Results showed that the piston–cylinder clearance affected the contact force, length of the contact region and leakage flow rate.

Originality/value

This result improves the understanding of the piston–cylinder lubrication and suggests considerations in terms of lubrication in clearance design.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 May 2018

Zhenpeng He

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

Industrial Lubrication and Tribology, vol. 70 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 2 March 2012

S.H. Mahdavi, S.H. Mansouri and A. Kimiaeifar

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Industrial Lubrication and Tribology, vol. 64 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 13 March 2017

Zhaoju Qin, Chenheng Yuan, Yanpeng Yuan and Yuanyuan Huang

A free-piston engine (FPE) is an unconventional engine that abandons the crank system. This paper aims to focus on a numerical simulation for the lubricating characteristics of…

221

Abstract

Purpose

A free-piston engine (FPE) is an unconventional engine that abandons the crank system. This paper aims to focus on a numerical simulation for the lubricating characteristics of piston rings in a single-piston hydraulic free-piston engine (HFPE).

Design/methodology/approach

A time-based numerical simulation program was built using Matlab to define the piston motion of the new engine. And a lubrication mode of piston rings was built which is based on the gas flow equation, hydrodynamic lubrication equation and the asperity contact equation. The piston motion and the lubrication model are coupled, and then the finite difference method is used to obtain the piston rings lubrication performances of the FPE. Meanwhile, the lubrication characteristics of the new engine were compared with those of a corresponding conventional crankshaft-driven engine.

Findings

The study results indicate that compared with the traditional engine, the expansion stroke of the HFPE is longer, and the compression stroke is shorter. Lubrication oil film of the new engine is thicker than the traditional engine during the initial stage of compression stroke and the final stage of the power stroke. The average friction force and power of the hydraulic free piston engine are slightly lower than those of the traditional engine, but the peak friction power of the FPE is significantly greater than that of the traditional engine. With an increase in load, the friction loss power and friction loss efficiency decrease, and with a decrease in equivalence ratio, the friction power loss reduces, but the friction loss efficiency decreases first and then increases.

Research limitations/implications

In this paper, only qualitative analysis was performed on the tribological difference between conventional crankshaft engine and HFPE, instead of a quantitative one.

Practical implications

This paper contributes to the tribological design method of HFPE.

Social implications

No social implications are available now, as the HFPE is under the development phase. However, the authors are positive that their work will be commercialized in the near future.

Originality/value

The main originality of the paper can be introduced as follows: the lubrication and friction characteristics of the new engine (HFPE) were investigated and revealed, which have not been studied before; the effect of the HFPE’s special piston motion on the tribological characteristics was considered in the lubrication simulation. The results show that compared with the traditional crankshaft engine, the new engine shows a different lubrication performance because of its free piston motion.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 March 2014

Adolfo Senatore and Dragan Aleksendric

This paper aims to propose a literature review of the main physical phenomena considered by previous studies focusing on the modelling and the numerical simulation of frictional…

Abstract

Purpose

This paper aims to propose a literature review of the main physical phenomena considered by previous studies focusing on the modelling and the numerical simulation of frictional behaviour of piston rings, in the first section. In the second section, the more recent technical papers and patents about piston ring pack are briefly discussed. They deal with novel materials, innovative manufacturing methods and modified shape for improving frictional, stability and blow-by behaviours.

Design/methodology/approach

This review paper aims at covering last period technical efforts about engine piston ring pack friction reduction through novel materials and manufacturing methods as well as new surface profiles according to the last outcomes of multiphysics numerical simulation.

Findings

The paper type is “literature review”. The findings of the authors of papers and patents are described.

Originality/value

This review paper proposes a survey of recent papers and patents on piston rings topic.

Details

Industrial Lubrication and Tribology, vol. 66 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 January 2018

Zhenpeng He, Wenqin Gong, Weisong Xie, Guichang Zhang and Zhenyu Hong

Piston ring dynamic problem plays an important role in the lubricant characteristics of a reciprocating engine, which lead to engine wear and the increased consumption of…

Abstract

Purpose

Piston ring dynamic problem plays an important role in the lubricant characteristics of a reciprocating engine, which lead to engine wear and the increased consumption of lubricating oil. A cavitation analysis of the piston ring lubrication with two-dimensional Reynolds equation has rarely been reported owing to the complex working condition. The purpose of this study is to establish a precise model that can provide guidance for the design of the piston ring.

Design/methodology/approach

In this paper, a cavitation model and its effect on the piston ring lubrication was studied in a simulation program based on the mass-conserving theory which is solved by means of the Newton–Raphson method. In this study, some models such as mixed lubrication, asperity contact, blow-by/blow-back flow and cavitation have been coupled with the lubrication model.

Findings

The established model has been compared with the traditional model that deals with cavitation by using the Reynolds boundary condition algorithm. The cavitation zone, pressure distribution and density distribution between the piston ring and the cylinder have also been predicted. Studies of the changing trend for the pressure distribution and the cavitation zone at few typical crank angles have been listed to illustrate the cavitation changing rule. The analysis of the results indicates that the developed simulation model can adequately illustrate the lubrication problem of the piston ring system. All the analyses will provide guidance for the oil film rupture and the reformation process.

Originality/value

A two-dimensional cavitation model based on the mass-conserving theory has been built. The cavitation-forming and -developing process for the piston ring–liner lubrication has been studied. Non-cavitation occurs in the vicinity of top dead center and bottom dead center. The non-cavitation period will be longer in the vicinity of 360° of crank angle. The density distribution in the cavitation zone can be obtained.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 26 September 2019

Gu Xin, Xiao-Ri Liu, Dong-Kang Cheng, Qing-Ping Zheng, Meng-Han Li, Nan-Nan Sun and Chun-Hua Min

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 13 March 2017

Yang Hu, Xianghui Meng, Youbai Xie and Jiazheng Fan

During running-in, the change in the honed cylinder liner surface alters the performance and efficiency of the piston ring-pack system. The present paper, thus, aims to…

Abstract

Purpose

During running-in, the change in the honed cylinder liner surface alters the performance and efficiency of the piston ring-pack system. The present paper, thus, aims to investigate the surface topography and wear and friction evolution of a cylinder liner surface during the running-in tests on a reciprocating ring–liner tribometer under a mixed lubrication regime. After an initial period of rapid wear termed “running-in wear”, a relatively long-term steady-state surface topography can emerge. A numerical model is developed to predict the frictional performance of a piston ring-pack system at the initial and steady-state stages.

Design/methodology/approach

The liner surfaces are produced by slide honing (SH) and plateau honing (PH). The bearing area parameter (Rk family), commonly used in the automotive industry, is used to quantitatively characterize the surface topography change during the running-in process. A wear volume-sensitive surface roughness parameter, Rktot, is used to show the wear evolution.

Findings

The experimental results show that a slide-honed surface leads to reduced wear, and it reduces the costly running-in period compared to the plateau-honed surface. The simulation results show that running-in is a beneficial wear process that leads to a reduced friction mean effective pressure at the steady-state.

Originality/value

To simulate the mixed lubrication performance of a ring–liner system with non-Gaussian roughness, a one-dimensional homogenized mixed lubrication model was established. The real surface topography instead of its statistical properties is taken into account.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of 262