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Variable compression in SI engines
Technical Paper
2001-24-0050
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Downsizing is an effective way to further improve the efficiency of SI engines. To make most of this concept, the compression ratio has to be adjusted during engine operation. Thus, the efficiency disadvantages during part load can be eliminated. A fuel consumption reduction of up to 30% can be realized compared to naturally aspirated engines of the same power.
After the assessment of several known concepts it turned out that the eccentric crankshaft positioning represents an appropriate solution which meets the requirements of good adjustability, unaltered inertia forces, low power demand of the positioning device and reasonable design effort. The basic challenges posed by the eccentric crankshaft positioning have been tackled, namely the crankshaft bearing and the integration of the newly developed power take-offs which have almost no influence on the base design.
The thermodynamic potential of the downsizing concept should justify the additional design effort and the related cost increase of the assembly.
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Citation
Pischinger, S., Yapici, K., Schwaderlapp, M., and Habermann, K., "Variable compression in SI engines," SAE Technical Paper 2001-24-0050, 2001, https://doi.org/10.4271/2001-24-0050.Also In
References
- Biermann, B. Habermann, K. Wolters P. Möglichkeiten und Grenzen der Hochaufladung am Ottomotor TAE Esslingen 1998
- Drangel, H. Bergsten L. Der neue Saab SVC Motor – Ein Zusammen- spiel zur Verbrauchsreduzierung von variabler Verdichtung, Hochaufladung und Downsizing 9 Aachener Kolloquium Fahrzeug- und Motorentechnik
- Bollig, C. Habermann, K. Marckwardt, H. Yapici K. I. Kurbeltrieb für variable Verdichtung MTZ 58 1997 11
- Habermann, K. Fieweger, K. Rauscher M. Aufladung von Ottomotoren als Maßnahme zur Verbrauchsverbesserung? HdT Tagung „Downsizingkonzepte für Otto- und Dieselfahrzeugmotoren“ München 26./27.06.2000
- Walzer, P. Adamis, P. Heinrich, H. Schumacher V. Variable Steuerzeiten und variable Verdichtung beim Ottomotor MTZ 47 1986 1