Influence of the compression ratio on the performance and emissions of a mini HCCI engine fuelled with diethyl ether
Författare
Summary, in English
In this paper, an investigation has been carried out concerning the effects of the compression ratio on the performance and emissions of a mini, Vd me 4.11 [cmu3], HCCI engine fueled with diethyl ether. Because of its high reactivity, autoignition of the mixture was achieved only using compression energy. The compression ratio was changed by altering the squish distance: 0.25, 0.50, 0.75, 1.00 and 1.25 [mm]. For each compression ratio, three sets of measurements were performed: 3000, 7000 and 12000 [rpm]. The study showed that diethyl ether was only slightly affected by quenching problems when the squish distance was 0.25 and 0.50 [mm] at 7000 [rpm]. It was also demonstrated that the performance improved when decreasing the compression ratio to an optimum point and subsequently dropped to zero when the highest spacer, 1.25 [mm], was used. Due to a very low combustion and thermodynamic efficiencies, the specific emissions of CO and HC were one order of magnitude higher than for a normal car/truck engine, whereas NOx emissions were comparable to those of a conventional diesel engine. Finally, the study rendered it possible to understand how much an HCCI engine fueled with diethyl ether could be scaled down since it was shown that this fuel was not very sensitive to quenching, with a squish distance of 0.25 [mm].
Avdelning/ar
Publiceringsår
2007
Språk
Engelska
Publikation/Tidskrift/Serie
SAE Technical Paper Series
Länkar
Dokumenttyp
Konferensbidrag
Förlag
Society of Automotive Engineers
Ämne
- Other Mechanical Engineering
Nyckelord
- power supply
- HCCI
- engine
- mini engine
- combustion
Conference name
SAE Powertrain & Fluid Systems Conference and Exhibition, 2007
Conference date
2007-10-29 - 2007-10-31
Conference place
Chicago, United States
Status
Published
Projekt
- VIMPA
ISBN/ISSN/Övrigt
- ISSN: 0148-7191
- SAE Technical Paper 2007-01-4075