Light Weight Pistons for Friction Optimized Spark Ignition Engines

2014 ◽  
Author(s):  
Dieter Gabriel ◽  
Jochen Adelmann ◽  
Thomas Hettich ◽  
Andreas Hammen
Keyword(s):  
Co2 Emissions ◽  
Spark Ignition ◽  
Design Concept ◽  
Design Approach ◽  
Light Weight ◽  
Spark Ignition Engines ◽  
Gasoline Engines ◽  
Highly Efficient ◽  
Low Co2

This article describes the development of MAHLE piston technology with the goal of meeting increasing requirements of advanced, highly efficient gasoline engines. The new EVOLITE® lightweight piston from MAHLE is a continuation of the development of its predecessor, the EVOTEC® 2, and is based on the EVOTEC® design concept. This concept differs from the design approach of previous decades in that the piston geometry has inverted asymmetry on the thrust and antithrust side. A narrow thrust side is combined with a wide, elastic antithrust side for skirt guidance. The light, robust EVOTEC® 2 piston is available with ring carrier or cooling gallery - Figure 1. The EVOLITE® concept represents further refinement of the EVOTEC® design concept by increasing asymmetry further. By geometrically optimizing the box wall connection between the skirt and crown, the lifetime has been increased by up to 8 times in comparison with the EVOTEC® 2, depending on stress location, while the weight has been reduced by up to 5%. Friction, which is critical for low CO2 emissions, is also reduced with this new piston type.

Numerical study of auto-ignition propagation modes in toluene reference fuel–air mixtures: Toward a better understanding of abnormal combustion in spark-ignition engines

2018 ◽  
Vol 20 (7) ◽  
pp. 734-745 ◽  
Author(s):  
Anthony Robert ◽  
Jean-Marc Zaccardi ◽  
Cécilia Dul ◽  
Ahmed Guerouani ◽  
Jordan Rudloff
Keyword(s):  
Numerical Study ◽  
Hot Spot ◽  
Lawrence Livermore National Laboratory ◽  
National Laboratory ◽  
Spark Ignition ◽  
Propagation Mode ◽  
Spark Ignition Engines ◽  
Gasoline Engines ◽  
Auto Ignition ◽  
Thermodynamic Conditions

Two main abnormal combustions are observed in spark-ignition engines: knock and low-speed pre-ignition. Controlling these abnormal processes requires understanding how auto-ignition is triggered at the “hot spot” but also how it propagates inside the combustion chamber. The original theory regarding the auto-ignition propagation modes was defined by Zeldovich and developed by Bradley who highlighted different modes by considering various hot spot characteristics and thermodynamic conditions around the hot spot. Two dimensionless parameters ( ε, ξ) were then defined to classify these modes and a so-called detonation peninsula was obtained for H2–CO–air mixtures. Similar simulations as those performed by Bradley et al. are undertaken to check the relevancy of the original detonation peninsula when considering realistic fuels used in modern gasoline engines. First, chemical kinetics calculations in homogeneous reactor are performed to determine the auto-ignition delay time τi, and the excitation time τe of E10–air mixtures in various conditions. These calculations are performed for a Research Octane Number (RON 95) toluene reference fuel surrogate with 42.8% isooctane, 13.7% n-heptane, 43.5% toluene, and using the Lawrence Livermore National Laboratory (LLNL) kinetic mechanism considering 1388 species and 5935 reactions. Results point out that H2–CO–air mixtures are much more reactive than E10–air mixtures featuring much lower excitation times τe. The resulting maximal hot spot reactivity ε is thus limited which also restrains the use of the detonation peninsula for the analysis of practical occurrences of auto-ignition in gasoline engines. The tabulated ( τi, τe) values are then used to perform one-dimensional Large Eddy Simulations (LES) of auto-ignition propagation considering different hot spots and thermodynamic conditions around them. The detailed analysis of the coupling conditions between the reaction and pressure waves shows thus that the different propagation modes can appear with gasoline, and that the original detonation peninsula can be reproduced, confirming for the first time that the propagation mode can be well defined by the two non-dimensional parameters for more realistic fuels.

Lightweight Design Concept for a Vehicle with Low CO2 Emissions

ATZ worldwide ◽  
2013 ◽  
Vol 115 (9) ◽  
pp. 50-55
Author(s):  
Wolfgang Fritz ◽  
Dietmar Hofer ◽  
Bruno Götzinger
Keyword(s):  
Co2 Emissions ◽  
Lightweight Design ◽  
Design Concept ◽  
Low Co2

Octane-on-Demand as an Enabler for Highly Efficient Spark Ignition Engines and Greenhouse Gas Emissions Improvement

2015 ◽  
Author(s):  
Junseok Chang ◽  
Yoann Viollet ◽  
Abdullah Alzubail ◽  
Amir Faizal Naidu Abdul-Manan ◽  
Abdullah Al Arfaj
Keyword(s):  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Spark Ignition ◽  
Spark Ignition Engines ◽  
Gas Emissions ◽  
On Demand ◽  
Highly Efficient

Lightweight vehicle Design Concept with Low CO2 Emissions

2014 ◽  
Vol 3 (2) ◽  
pp. 24-29
Author(s):  
Wolfgang Fritz ◽  
Dietmar Hofer ◽  
Bruno Götzinger
Keyword(s):  
Co2 Emissions ◽  
Design Concept ◽  
Vehicle Design ◽  
Low Co2

scholarly journals General Correlations of Iso-octane Turbulent Burning Velocities Relevant to Spark Ignition Engines

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1848
Author(s):  
Minh Tien Nguyen ◽  
Dewei Yu ◽  
Chunyen Chen ◽  
Shenqyang (Steven) Shy
Keyword(s):  
Burning Velocity ◽  
Lewis Number ◽  
Spark Ignition ◽  
Spark Ignition Engines ◽  
Laminar Burning Velocity ◽  
Gasoline Engines ◽  
Turbulent Premixed Flame ◽  
Spherical Flames ◽  
Scaling Parameters ◽  
Self Similar

A better understanding of turbulent premixed flame propagation is the key for improving the efficiency of fuel consumption and reducing the emissions of spark ignition gasoline engines. In this study, we measure turbulent burning velocities (ST) of pre-vaporized iso-octane/air mixtures over wide ranges of the equivalence ratio (φ = 0.9–1.25, Le ≈ 2.94–0.93), the root-mean-square (r.m.s.) turbulent fluctuating velocity (u′ = 0–4.2 m/s), pressure p = 1–5 atm at T = 358 K and p = 0.5–3 atm at T = 373 K, where Le is the effective Lewis number. Results show that at any fixed p, T and u′, Le < 1 flames propagate faster than Le > 1 flames, of which the normalized iso-octane ST/SL data versus u′/SL are very scattering, where SL is the laminar burning velocity. But when the effect of Le is properly considered in some scaling parameters used in previous correlations, these large scattering iso-octane ST/SL data can be collapsed onto single curves by several modified general correlations, regardless of different φ, Le, T, p, and u′, showing self-similar propagation of turbulent spherical flames. The uncertainty analysis of these modified general correlations is also discussed.

scholarly journals Sustainability Investigation of Vehicles’ CO2 Emission in Hungary

2021 ◽  
Vol 13 (15) ◽  
pp. 8237
Author(s):  
István Árpád ◽  
Judit T. Kiss ◽  
Gábor Bellér ◽  
Dénes Kocsis
Keyword(s):  
Energy Efficiency ◽  
Co2 Emissions ◽  
Energy Supply ◽  
Internal Combustion Engines ◽  
Combustion Engines ◽  
The European Union ◽  
New Approach ◽  
Technology System ◽  
Low Co2

The regulation of vehicular CO2 emissions determines the permissible emissions of vehicles in units of g CO2/km. However, these values only partially provide adequate information because they characterize only the vehicle but not the emission of the associated energy supply technology system. The energy needed for the motion of vehicles is generated in several ways by the energy industry, depending on how the vehicles are driven. These methods of energy generation consist of different series of energy source conversions, where the last technological step is the vehicle itself, and the result is the motion. In addition, sustainability characterization of vehicles cannot be determined by the vehicle’s CO2 emissions alone because it is a more complex notion. The new approach investigates the entire energy technology system associated with the generation of motion, which of course includes the vehicle. The total CO2 emissions and the resulting energy efficiency have been determined. For this, it was necessary to systematize (collect) the energy supply technology lines of the vehicles. The emission results are not given in g CO2/km but in g CO2/J, which is defined in the paper. This new method is complementary to the European Union regulative one, but it allows more complex evaluations of sustainability. The calculations were performed based on Hungarian data. Finally, using the resulting energy efficiency values, the emission results were evaluated by constructing a sustainability matrix similar to the risk matrix. If only the vehicle is investigated, low CO2 emissions can be achieved with vehicles using internal combustion engines. However, taking into consideration present technologies, in terms of sustainability, the spread of electric-only vehicles using renewable energies can result in improvement in the future. This proposal was supported by the combined analysis of the energy-specific CO2 emissions and the energy efficiency of vehicles with different power-driven systems.

scholarly journals Ethanol/Gasoline Blends as Alternative Fuel in Last Generation Spark-Ignition Engines: A Review on CO and HC Engine Out Emissions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4034
Author(s):  
Paolo Iodice ◽  
Massimo Cardone
Keyword(s):  
Physicochemical Properties ◽  
Alternative Fuels ◽  
Experimental Studies ◽  
Alternative Fuel ◽  
Exhaust Emissions ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
The Impact

Among the alternative fuels existing for spark-ignition engines, ethanol is considered worldwide as an important renewable fuel when mixed with pure gasoline because of its favorable physicochemical properties. An in-depth and updated investigation on the issue of CO and HC engine out emissions related to use of ethanol/gasoline fuels in spark-ignition engines is therefore necessary. Starting from our experimental studies on engine out emissions of a last generation spark-ignition engine fueled with ethanol/gasoline fuels, the aim of this new investigation is to offer a complete literature review on the present state of ethanol combustion in last generation spark-ignition engines under real working conditions to clarify the possible change in CO and HC emissions. In the first section of this paper, a comparison between physicochemical properties of ethanol and gasoline is examined to assess the practicability of using ethanol as an alternative fuel for spark-ignition engines and to investigate the effect on engine out emissions and combustion efficiency. In the next section, this article focuses on the impact of ethanol/gasoline fuels on CO and HC formation. Many studies related to combustion characteristics and exhaust emissions in spark-ignition engines fueled with ethanol/gasoline fuels are thus discussed in detail. Most of these experimental investigations conclude that the addition of ethanol with gasoline fuel mixtures can really decrease the CO and HC exhaust emissions of last generation spark-ignition engines in several operating conditions.

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