Paul Kapus

Range extender module

The use of AVLs Pure Range Extender module as a serial hybrid solution is described. The AVL concept is optimised for electric power generation in single-point operation and allows a compactly integrated, cost- and weight-efficient module design. In addition to its use in simplified four-stroke designs the Pure Range Extender can be applied to emission-optimised and fuel consumption-optimised two-stroke and rotary piston engines. Details are given of the reductions in weight and running costs and the increases in range that can be achieved. The development process is discussed and the key specifications of the Pure Range Extender provided in a table. The design of the internal combustion engine and generator-starter are considered in more detail. A feature of the system is its flexible design which will allow its use in a wide variety of vehicles.

The gasoline engine and RDE challenges and prospects

Whereas in the past decade, the CO2 reduction was the major driver for technology development with Gasoline en.gines, especially after the “Dieselgate” an “Extended Emission Compliance” including Real Drive Emissions is taking significant impact on future technology routes. Whereas the RDE legislation initially was targeted primarily towards the Diesel-NOx and the Gasoline-PN emissions, now also the NOx emissions of some Gasoline engine concepts have to be reduced.

Reduction of particulate number emissions through calibration methods

The ever-stricter emission limits for passenger cars are continually posing new challenges for engine development. The European Union with the introduction of Euro 5 has for the first time a gasoline emission standard for particulate mass, with Euro 6 in addition to particulate mass there will be a limit for the particulate number. AVL has investigated the possibilities of reducing internal engine particulate emissions, developed concepts for future emissions and tested the potential for the reduction of particulates by calibration methods.

Laser induced ignition

Nowadays, combustion engines and other combustion processes play an overwhelming and important role in everyday life. As a result, ignition of combustion processes is of great importance, too. Usually, ignition of a combustible material is defined in such a way that an ignition initiates a self-sustained reaction which propagates through the inflammable material even in the case that the ignition source has been removed. In most cases, a well defined ignition location and ignition time is of crucial importance. Spark plugs are well suited for such tasks but suffer from some disadvantages, like erosion of electrodes or restricted positioning possibilities. In some cases, ignition of combustible materials by means of high power laser pulses could be beneficial. High power lasers offer several different possibilities to ignite combustible materials, like thermal ignition, resonant ignition or optical breakdown ignition. Since thermal and resonant ignitions are not well suited on the requirements mentioned previously, only optical breakdown ignition will be discussed further. Optical breakdown of a gas within the focal spot of a high power laser allows a very distinct localization of the ignition spot in a combustible material. Since pulse duration is usually in the range of several nanoseconds, requirements on the ignition time are fulfilled easily, too. Laser peak intensities required for such an optical breakdown are in the range of 1011 W/cm2. The hot plasma which forms during this breakdown initiates the following self-propagating combustion process. It has been shown previously that laser ignition of direct injection engines improves the fuel consumption as well as the exhaust emissions of such engines significantly. The work presented here gives a brief overview on the basics of laser induced ignition. Flame propagation which follows a successful ignition event can be distinguished into two diffrent regimes. Combustion processes within an engine are usually quite slow - the reaction velocity is mainly determined by the heat conductivity of the combustible. Such deflagrations processes show propagation velocities well below the speed of sound. On the other hand, detonations show much higher propagation velocities. In contrast to deflagrations, detonations show propagation velocities higher than the speed of sound within the combustible. The shock front which propagates through a combustible in the case of a detonation is responsible for a considerable pressure gradient moving at supersonic velocity. Basics and possible examples of laser induced ignitions of deflagrations and detonations are given and pros and cons of laser ignition systems are discussed briefly.

Range-Extender-Modul. Wegbereiter fuer elektrische Mobilitaet

Fur eine breite Akzeptanz von Elektrofahrzeugen erscheint ein Range-Extender als serielles Hilfsaggregat fur einzelne langere Fahrstrecken von entscheidender Bedeutung. Der Ansatz von AVL ist auf Batterienachladung im Einpunktbetrieb ausgelegt und ermoglicht ein kompakt integriertes, gewichts- und kostenoptimiertes Modul. Der Verbrennungsmotor des sogenannten Pure-Range-Extenders von AVL kann neben vereinfachten Viertakt-Konzepten auch als, fur die Anwendung optimierter, Zweitakt- beziehungsweise Rotationskolbenmotor ausgefuhrt werden

Mehrwertorientierte Techniken für ottomotorische Antriebssysteme

Eine konsequente Mehrwertorientierung lasst sich beim Ottomotor in verschiedener Weise umsetzen. Beim AVL-CBR-System der dritten Generation wird durch Integration der variablen Ladungsbewegung in die Funktion der Restgassteuerung mittels Phasenschieber und Auslassventilmaskierung der Systemaufwand bei praktisch gleicher Funktionalitat deutlich reduziert. Das verbrauchs- und fahrspasorientierte DGI-tc Aufladekonzept von AVL steigert durch forcierte Nutzung von Synergieeffekten zwischen Direkteinspritzung, Nockenwellen-Phasenschieber und Abgasturboaufladung den Kundennutzen in Form von signifikanter Verbrauchsreduzierung und vergrosertem Fahrspas uberproportional zum Mehraufwand.

Reduzierung der Partikelanzahl durch applikative Massnahmen

Die stetig strenger werdenden Emissionsgrenzwerte fur Pkw stellen immer neue Herausforderungen an die Motorentwicklung. Die Europaische Union fuhrte mit der Gesetzesstufe Euro 5 erstmals Emissionsgrenzwerte fur die Partikelmasse bei Ottomotoren ein, ab Euro 6 soll zusatzlich zur Partikelmasse erstmals auch ein Grenzwert fur die Partikelanzahl folgen. AVL hat die innermotorischen Moglichkeiten der Reduktion von Partikelemissionen untersucht, Strategien fur kunftige Emissionskonzepte entwickelt und auch die mogliche Absenkung der Partikel durch applikative Masnahmen gepruft.

Gasoline engine technologies focused on multiple benefit

Multiple benefit can be obtained in various ways in gasoline engine development through the consequent persual of this as goal. With the AVL-CBR 3 system, for example, the total cost can be significantly reduced by integrating the functionality of variable charge motion directly into the residual gas control by cam phaser. The AVL DGI-tc fuel economy and fun-to-drive concept achieved through uncompromising exploitation of the synergy effects between direct injection, cam phase shifter, turbocharging and exhaust valve masking increases customer benefits disproportionately greater than the increase in cost incurred.

Irregular Combustion Events in RDE Test Situations Diagnostics – Analysis – Improvements

The paper describes a method to identify and analyze pre-ignition (PI) events appearing in engine and vehicle RDE drive cycle tests or similar transient and stationary test schedules. A specific requirement in such long duration drive cycles is the large amount of data to be recorded for each combustion cycle and the data processing during and after a test procedure. Identification of PI events is accomplished with measurement of ignition delay time, i.e. spark discharge timing and the instant when flame growth is detected. PI events show up with negative ignition delay. How this simple concept is implemented in a combustion measurement procedure with many thousand cycles is explained in some detail. Classification of PI events and root cause analysis is then supported with evaluation of the optical signals of the tests. Specific evaluation procedures to accomplish such task have been described in earlier publications.

Partikeloptimale Benzindirekteinspritzung – Eine Voraussetzung für RDE

Zu den Kerngebieten moderner Fahrzeugentwicklung zahlt die Minimierung der Emissionen im kundenrelevanten Alltagsbetrieb. Diese „Real Driving Emissions“ (RDE) stehen auch im Mittelpunkt zukunftiger PKW-Emissionsgesetzgebungsentwicklungen der Europaischen Union. Die Neuerungen mit EU6c ab 2017 bzw. darauffolgende Entwicklungsstufen werden mit hoher Wahrscheinlichkeit Emissionsmessungen auf offentlichen Strasen mittels mobiler Emissionsmesstechnik (PEMS) als neues Teilelement der Typprufung erfordern. Das Ziel bleibt daher, eine besonders hohe Emissionsrobustheit bei der Motor- und Abgasnachbehandlungsentwicklung unter den Anforderungen sich andernder Umwelteinflusse, verschiedener Fahrstile und Streckenbeschaffenheiten in den Vordergrund zu stellen.