Predictive tool for frictional performance of piston ring-pack/liner conjunction
DOI:
https://doi.org/10.15282/jmes.13.3.2019.19.0445Keywords:
Piston ring-pack, Lubrication, Engine in-cylinder friction, Reynolds’ equation, Rough surface contact modelAbstract
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.
References
U.S. Energy Information Administration. Retrieved from https://www.eia.gov/outlooks/ieo/pdf/0484(2017).pdf; 10 June, 2019.
Holmberg K, Erdemir A. The impact of tribology on energy use and CO2 emission globally and in combustion engine and electric cars. Tribology International. 2019.
Chong WWF, Ng JH, Rajoo S, Chong CT. Passenger transportation sector gasoline consumption due to friction in Southeast Asian countries. Energy conversion and management. 2018; 158: 346-358.
Wong VW, Tung SC. Overview of automotive engine friction and reduction trends–Effects of surface, material, and lubricant-additive technologies. Friction. 2016; 1: 1-28.
Tung SC, McMillan ML. Automotive tribology overview of current advances and challenges for the future. Tribology International. 2004; 37(7): 517-536.
Morris N, Mohammadpour M, Rahmani R, Rahnejat H. Optimisation of the piston compression ring for improved energy efficiency of high-performance race engines. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. 2017; 231(13): 1806-1817.
Chong WWF, De la Cruz M. Elastoplastic contact of rough surfaces: a line contact model for boundary regime of lubrication. Meccanica. 2014; 49(5) : 1177-1191.
Shahmohamadi H, Mohammadpour M, Rahmani R, Rahnejat H, Garner CP, Howell-Smith S. On the boundary conditions in multi-phase flow through the piston ring-cylinder liner conjunction. Tribology International. 2015; 90 :164-174.
Mufti RA, Priest M. Experimental evaluation of piston-assembly friction under motored and fired conditions in a gasoline engine. Journal of Tribology. 2005; 127(4) : 826-836.
Gore M, Theaker M, Howell-Smith S, Rahnejat H, King PD. Direct measurement of piston friction of internal-combustion engines using the floating-liner principle. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. 2014; 228(3) : 344-354.
Westerfield Z, Totaro P, Kim D, Tian T. An experimental study of piston skirt roughness and profiles on piston friction using the floating liner engines. SAE Technical Paper. 2016; 1043.
Fang C, Meng X, Xie Y, Wen C, Liu R. An improved technique for measuring piston-assembly friction and comparative analysis with numerical simulations: Under motored condition. Mechanical Systems and Signal Processing. 2019; 115: 657-676.
Miltsios GK, Patterson DJ, Papanastasiou TC. Solution of the lubrication problem and calculation of the friction force on the piston rings. Journal of Tribology. 1989; 111(4): 635-641.
Zhao B, Dai XD, Zhang ZN, Xie YB. A new numerical method for piston dynamics and lubrication analysis. Tribology International. 2016;94 :395-408.
Jeng YR. Theoretical analysis of piston-ring lubrication Part I—fully flooded lubrication. Tribology Transactions. 1992;35(4) :696-706.
Rahmani R, Theodossiades S, Rahnejat H, Fitzsimons B. Transient elastohydrodynamic lubrication of rough new or worn piston compression ring conjunction with an out-of-round cylinder bore. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology. 2012; 226(4):284-305.
Chong WWF, Howell-Smith S, Teodorescu M, Vaughan ND. The influence of inter-ring pressures on piston-ring/liner tribological conjunction. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology. 2013; 227(2) :154-167.
Greenwood JA, Williamson JP. Contact of nominally flat surfaces. Proc. R. Soc. Lond. A. 1966; 295(1442) :300-319.
Chong WWF, Teodorescu M, Rahnejat, H. Nanoscale elastoplastic adhesion of wet asperities. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology. 2013; 227(9) : 996-1010.
Teodorescu M, Taraza D, Henein NA, Bryzik W. Simplified elasto-hydrodynamic friction model of the cam-tappet contact. SAE Technical Paper 2003. 2003;01:0985.
Miao X, Huang X. A complete contact model of a fractal rough surface. Wear. 2014; 309(1-2) :146-151.
Etsion I. Improving tribological performance of mechanical components by laser surface texturing. Tribology letters. 2004; 17(4) : 733-737.
Ryk G, Etsion I. Testing piston rings with partial laser surface texturing for friction reduction. Wear. 2006; 261(7-8) : 792-796.
Rahnejat H, Balakrishnan S, King PD, Howell-Smith S. In-cylinder friction reduction using a surface finish optimization technique. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. 2006;220(9) :1309-1318.1
Vlădescu SC, Ciniero A, Tufail K, Gangopadhyay A, Reddyhoff T. Looking into a laser textured piston ring-liner contact. Tribology International. 2017;115 :140-153.
Gu C, Meng X, Xie Y, Yang Y. Effects of surface texturing on ring/liner friction under starved lubrication. Tribology international. 2016;94 : 591-605.
Morris N, Rahmani R, Rahnejat H, King PD, Howell-Smith S. A numerical model to study the role of surface textures at top dead center reversal in the piston ring to cylinder liner contact. Journal of Tribology. 2016;138(2):021703.
Sahid NSM, Rahman MM, Kadirgama K, Maleque MA. Experimental investigation on properties of hybrid nanofluids (TiO2 and ZnO) in water–ethylene glycol mixture. Journal Of Mechanical Engineering And Sciences. 2017;11: 3087-3094.
Sharma S, Tiwari AK, Tiwari S, Prakash R. Viscosity of hybrid nanofluids: Measurement and comparison. Journal Of Mechanical Engineering And Sciences. 2018; 12 : 3614-3623.
Ng YC, Hamdan SH, Chong WWF. Development of a mathematical tool to predict engine in-cylinder friction. Jurnal Tribologi. 2018; 17:29-39.
Alias AA, Kinoshita H, Nishina Y, Fuji M. Dependence of pH level on tribological effect of graphene oxide as an additive in water lubrication. International Journal of Automotive and Mechanical Engineering. 2016;13: 3150.
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