Increasing the Efficiency of the  Internal Combustion Engine  through Extended Expansion

Dumböck, Ortwin; Schutting, Eberhard; Eichlseder, Helmut; Hübner, Walter

doi:10.1007/s38313-018-0108-3

Cited by 3 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…An overexpanded cycle engine with such a complex connecting rods system is not actually used in a vehicle. Yet, research has been made on the subject, we can mention BMW [50] and Honda with the EXlink engine [51], [52]. The major disadvantages are friction losses, inertia of the extra parts and the bigger space needed.…”

Section: Presentation Of the Cyclementioning

confidence: 99%

Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

Perceau

Guibert

Guilain

2021

Applied Thermal Engineering

View full text Add to dashboard Cite

Section: Presentation Of the Cyclementioning

confidence: 99%

Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

Perceau

Guibert

Guilain

2021

Applied Thermal Engineering

View full text Add to dashboard Cite

“…Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) often have the thermal efficiency which exceed 50% [13,14]. Generally, average efficiency of IC engines under the ideal working regime is about 30% in automotive application and around 45% for watercraft [15,16].…”

Section: Introductionmentioning

confidence: 99%

Correlation between Emission and Combustion Characteristics with the Compression Ratio and Fuel Injection Timing in Tribologically Optimized Diesel Engine

2022

Teh. vjesn.

View full text Add to dashboard Cite

Diesel engines are economical thanks to their combustion process characteristics, which is why they have a high noise emission level as well as exhaust emissions of nitrogen oxide and particulate matters. By continuously changing the value of compression ratio, it is possible to control the power and emissions. Implementation of variable compression ratio has many benefits, such as being able to work with different types of fuel. In this way, it is possible to optimize the combustion process for operation with minimum fuel consumption and emission generation, so that diesel engines can be applied to the framework of future hybrid vehicle concepts, and so forth. As far as the crucial objective of the manuscript is concerned, experimental diesel engine investigation was performed on a roller test-bench by using zero-dimensional computer model (specifically AVL IndiCom Indicate Software). Engine indication was executed with the factory compression ratio value and with three lower values. During our examination, the change in the compression ratio value was achieved by changing the volume of a combustion chamber at a piston-bowl. The results of laboratory research on the experimental engine are presented in the paper when discussing a series of specific parameters (characteristics), such as compression ratio, fuel injection timing, engine speed, as well as load influence on combustion process and exhaust emissions.

show abstract

“…Un moteur à détente prolongée de ce type, disposant d'un embiellage complexe, n'est actuellement pas commercialisé dans un véhicule. Des recherches ont été menées sur ce même sujet par les entreprises BMW [12] et Honda, avec son moteur EXlink [13], [14]. Les principaux inconvénients de ces moteurs sont les pertes par friction, l'inertie des pièces ajoutées et l'encombrement du système.…”

Section: Introductionunclassified

Modélisation 0D turbulente d’un moteur essence en vue de sa Millérisation

Perceau¹,

Guibert²,

Guilain³

2020

Entropie

View full text Add to dashboard Cite

Les nouvelles restrictions environnementales poussent les constructeurs automobiles à s'intéresser aux cycles à détente prolongée et à laisser de côté le classique cycle de Beau de Rochas. Le cycle de Miller fait partie de cette famille de cycle et peut s'appliquer simplement aux moteurs à allumage commandé en modifiant le diagramme de fermeture des soupapes d'admission. Le moteur effectue une détente plus importante que la phase de compression effective. La millérisation d'un moteur se fait en augmentant la taille de celui-ci et en fermant les soupapes d'admission en avance. L'instant de fermeture est choisi de manière à suivre la même phase de compression effective que le moteur de référence. Cette démarche est connue sous le nom de « rightsizing ». Ce papier décrit une approche zéro dimensionnelle pour estimer les bénéfices obtenus par la millérisation d'un moteur de référence. Le modèle comprend un sous modèle de transfert thermique, basé sur la corrélation du coefficient de convection de Woschni, ainsi qu'un sous modèle de frottements qui permet de prendre en compte l'effet d'une augmentation de la taille. La fermeture prématurée des soupapes d'admission du cycle de Miller tend à réduire l'intensité des mouvements aérodynamiques internes au cylindre, le niveau de turbulence en fin de compression est donc réduit. Ce phénomène augmente la durée de combustion et affecte le rendement. Un modèle de turbulence K-k-ε est utilisé pour estimer l'intensité de la turbulence en fin de compression. Une relation entre la durée de combustion et la turbulence est proposé. Pour le moteur de référence, les gains obtenus par millérisation permettent l'augmentation d'un point de rendement, correspondant à une amélioration d'efficacité d'environ 3%, valeur très significative pour un rendement. ABSTRACT. New environmental regulations are encouraging automakers to focus on over-expanded cycles and to set aside the classic Otto cycle. The Miller cycle is part of this family of cycles and can be applied to spark ignition engines easily by modifying the intake valve closing event. The engine expands more than the actual compression phase. The millerization of an engine is done by increasing the size of the engine and closing the intake valves in advance. The closing time is chosen to follow the same effective compression phase as the reference engine. This process is known as "rightsizing". This paper describes a zero-dimensional approach to estimate the benefits obtained by millerization of a reference engine. The model includes a heat transfer sub-model, based on the Woschni coefficient, as well as a friction sub-model that allows us to take into account the effect of an increase in size. Premature closure of the intake valves in the Miller cycle tends to reduce the intensity of aerodynamic movements within the cylinder, so the level of turbulence at the end of compression is reduced. This phenomenon increases combustion duration and affects efficiency. A K-k-ε turbulence model is used to estimate the intensity of turbulence at the...

show abstract

Increasing the Efficiency of the Internal Combustion Engine through Extended Expansion

Cited by 3 publications

References 0 publications

Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

Correlation between Emission and Combustion Characteristics with the Compression Ratio and Fuel Injection Timing in Tribologically Optimized Diesel Engine

Modélisation 0D turbulente d’un moteur essence en vue de sa Millérisation

Contact Info

Product

Resources

About