Improving the tribological behavior of internal combustion engines via the addition of nanoparticles to engine oils

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Mohamed Kamal Ahmed Ali ◽  
Hou Xianjun
Keyword(s):  
Internal Combustion Engines ◽  
Tribological Behavior ◽  
Internal Combustion ◽  
Valve Train ◽  
Combustion Engines ◽  
Power Losses ◽  
Oil Consumption ◽  
Engine Oils ◽  
Engine Efficiency ◽  
Sliding Surfaces

AbstractThe friction between two sliding surfaces is probably one of the oldest problems in mechanics. Frictional losses in any I.C. engine vary between 17% and 19% of the total indicated horse power. The performance of internal combustion engines in terms of frictional power loss, fuel consumption, oil consumption, and harmful exhaust emissions is closely related to the friction force and wear between moving parts of the engine such as piston assembly, valve train, and bearings. To solve this problem, most modern research in the area of Nanotribology (Nanolubricants) aims to improve surface properties, reduce frictional power losses, increase engine efficiency, and reduce consumed fuel and cost of maintenance. Nanolubricants contain different nanoparticles such as Cu, CuO, TiO

Piston ring–liner lubrication and tribological performance evaluation: A review

2017 ◽  
Vol 232 (2) ◽  
pp. 193-209 ◽  
Author(s):  
Cristiana Delprete ◽  
Abbas Razavykia
Keyword(s):  
Internal Combustion Engines ◽  
Piston Ring ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Power Losses ◽  
Oil Consumption ◽  
Major Power ◽  
Power Sources ◽  
Engine Efficiency

Internal combustion engines are at present used as the major power sources for transportation and power generator. Improvement of the internal combustion engine efficiency is expected due to strict environmental standards and energy costs. Any reduction in oil consumption, friction power losses and emissions results in improving engines’ performance and durability. Automotive industries have intense passion to increase engines’ efficiency to meet the fuel economy and emission standards. Many studies have been conducted to develop reliable approaches and models to understand the lubrication mechanisms and calculate power losses. This review paper summarizes the synthesis of the main technical aspects considered during modeling of piston ring–liner lubrication and friction losses investigations. The literature review highlights the effects of piston ring dynamics, components geometry, lubricant rheology, surface topography and adopted approaches, on frictional losses contributed by the piston ring-pack.

Nonlinear Transient Response of a High Speed Driven Valve System and Stresses in Valve Springs for Internal Combustion Engines

1989 ◽  
Vol 111 (3) ◽  
pp. 264-271 ◽  
Author(s):  
K. Nagaya
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Three Dimensional ◽  
Beam Theory ◽  
Internal Combustion ◽  
Valve Train ◽  
Combination Method ◽  
Combustion Engines ◽  
Valve System ◽  
Cam Profile

This paper presents a method for solving the dynamic response problems of a driven valve system and the stress problem of valve springs for internal combustion engines. In this system there is hysteresis behavior in the spring constants during the rotation of the cam shaft. To treat this nonlinearity, the rigidity of each section is assumed to be one of a partly linear spring. For the valve trains, the cam profile is complex in general. To treat a general cam profile, this paper applies a combination method of the Fourier expansion, the Laplace transform and the analytical connection methods, and gives a response of valve trains. This paper also presents a theoretical result for the stresses in the valve spring due to the motion of the valve train based on the three dimensional curved beam theory.

Performance study of the hypocycloid gear mechanism for internal combustion engine applications

2019 ◽  
pp. 146808741989358 ◽  
Author(s):  
Mostafa A ElBahloul ◽  
ELsayed S Aziz ◽  
Constantin Chassapis
Keyword(s):  
Internal Combustion Engine ◽  
Thermodynamic Model ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Otto Cycle ◽  
Engine Efficiency ◽  
Gear Mechanism ◽  
Crank Mechanism

Fuel conversion efficiency is one of the main concerns in the field of internal combustion engine systems. Although the Otto cycle delivers the maximum efficiency possible in theory, the kinematics of the slider–crank mechanism of the conventional internal combustion engines makes it difficult to reach this level of efficiency in practice. This study proposes using the unique hypocycloid gear mechanism instead of the conventional slider–crank mechanism for the internal combustion engines to increase engine efficiency and minimize frictional power losses. The hypocycloid gear mechanism engine’s kinematics provides the means for the piston-rod assembly to reciprocate in a straight-line motion along the cylinder axis besides achieving a nonlinear rate of piston movement. As a result, this characteristic allows for a true constant-volume combustion, which in turn would lead to higher work output. An in-cylinder gas volume change model of the hypocycloid gear mechanism engine was developed and incorporated into the thermodynamic model for the internal combustion engine cycle. The thermodynamic model of the hypocycloid gear mechanism engine was developed and simulated using MATLAB/Simulink software. A comparison between the conventional engine and the hypocycloid gear mechanism engine in terms of engine performance characteristics showed the enhancements achieved using hypocycloid gear mechanism for internal combustion engine applications. The hypocycloid gear mechanism engine analysis results indicated higher engine efficiency approaching that of the Otto cycle.

Experimental Investigation of Oil Accumulation in Second Land of Internal Combustion Engines

2005 ◽  
Vol 127 (1) ◽  
pp. 206-212
Author(s):  
T. Icoz ◽  
Z. Dursunkaya
Keyword(s):  
Film Thickness ◽  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Engine Oil ◽  
Combustion Engines ◽  
Oil Consumption ◽  
Oil Accumulation ◽  
Oil Film ◽  
Piston Cylinder ◽  
Total Oil

Blowback of engine oil suspended in combustion gases, when the gas flows from the piston second land back into the combustion chamber, is believed to contribute to oil consumption and hydrocarbon emissions in internal combustion engines. Oil accumulation in the region between top and second compression rings is a factor that influences this phenomenon. The effects of individual parameters, such as oil film thickness and viscosity, however, have still not been understood. The present study was aimed at constructing an experimental setup to study the effect of oil film thickness on oil accumulation in the second land of internal combustion engines. Due to the inherent difficulties of experimentation on production engines, a modeled piston-cylinder assembly was constructed. Total oil accumulation in the modeled second land after a single piston stroke was measured and compared to oil consumption in operating engines.

A New Methodology for Calculating and Modelling Non-Linear Springs in the Valve Train of Internal Combustion Engines

2011 ◽  
Author(s):  
Gaetano Sequenzia ◽  
Salvatore Oliveri ◽  
Michele Calabretta ◽  
Gabriele Fatuzzo ◽  
Michele Cali
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Valve Train ◽  
Combustion Engines ◽  
Non Linear

scholarly journals Theoretical Performance Comparison between Inline, Offset and Twin Crankshaft Internal Combustion Engines

2008 ◽  
Vol 3 (1) ◽  
pp. 17
Author(s):  
Taj Elssir Hassan ◽  
Abdelfattah Bilal ◽  
Maisara Mohy Eldin Gasim
Keyword(s):  
Internal Combustion Engines ◽  
Thrust Force ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Performance Comparison ◽  
Combustion Engines ◽  
Engine Efficiency ◽  
Output Torque ◽  
Computational Work ◽  
Cylinder Bore

The twin crankshaft engine is anew configuration of internal combustion engine that introduced to solve the engine liner wear problems, increase the engine efficiency and it has other advantages over conventional engines. In this research, a computational work was carried out to compare the performance of three l engine configurations, namely, the conventional (inline) engine, the offset crankshaft engine and the twin crankshaft engine, of the same cylinder bore, speed, crank arm, piston mass and heat addition. The performance measured was the side thrust force that causes liner wear and the output torque. Results showed that the twin crankshaft engine is superior in terms of torque which means it has larger efficiency than the other configurations.

Applying Thermodynamics in Search of Superior Engine Efficiency

2005 ◽  
Vol 127 (3) ◽  
pp. 670-675 ◽  
Author(s):  
Charles A. Amann
Keyword(s):  
Thermal Efficiency ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Heat Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Closed Cycle ◽  
Engine Efficiency ◽  
Operating Cycles ◽  
Thermodynamic Processes

Historically, a succession of thermodynamic processes has been used to idealize the operating cycles of internal combustion engines. In this study, the 256 possible combinations of four reversible processes—isentropic, isothermal, isochoric, and isobaric—are surveyed in search of cycles promising superior thermal efficiency. Regenerative cycles are excluded. The established concept of the air-standard cycle, which mimics the internal combustion engine as a closed-cycle heat engine, is used to narrow the field systematically. The approach relies primarily on graphical interpretation of approximate temperature-entropy diagrams and is qualitative only. In addition to identifying the cycles offering the greatest efficiency potential, the compromise between thermal efficiency and mean effective pressure is addressed.

Sign in / Sign up

Export Citation Format

Share Document