Experimental investigation of diesel/gasoline dual-fuel premixed compression ignition strategies for high thermal efficiency and high load extension

Abstract

In this study, two different operating strategies of gasoline and diesel dual-fuel premixed compression ignition (PCI) were investigated by using a single cylinder compression ignition engine. Verification of high thermal efficiency potential under the low load condition and the suppression of the maximum in-cylinder pressure rise rate (PRRmax) under the relatively high load condition were considered in this study. Two approaches to implement dual-fuel PCI were considered. The first approach (A-mode PCI) was an early diesel injection with very leaner overall equivalence ratio condition. In this case, a high exhaust gas recirculation (EGR) rate was not needed because lean premixed combustion promised to provide low nitrogen oxides (NOx) and particulate matter (PM) emissions. The second method (B-mode PCI) involved the use of a high EGR rate to moderate dual-fuel combustion with adjusting diesel injection timing. The first operating strategy prolonged the ignition delay via early diesel injection and lean mixture condition; in this manner, a high EGR helped to increase ignition delay. The experimental result showed that the A-mode PCI strategy promised higher gross indicated thermal efficiency (GIE) than that of the B-mode PCI. However, the B-mode PCI strategy provided a lower PRRmax than that of the first case. By applying the A-mode PCI, which was implemented by the early diesel injection with overall lean premixed combustion, a high GIE of 47.8 % could be obtained under low speed and low load condition. In addition, the dual-fuel PCI operating range could be increased using a gross indicated mean effective pressure (gIMEP) of 14 bar at 2000 r/min with a low PRRmax of 7 bar/deg (constraint 10 bar/deg) by applying the B-mode PCI strategy, which split the heat release rate (HRR) peaks to enable smooth combustion.

Keywords

Dual-fuel combustion gross indicated thermal efficiency pressure rise rate;nitrogen oxides (NOx)particulate matter premixed compression ignition

Get full access to this article

View all access options for this article.

References

Heywood

JB.

Internal combustion engine fundamentals. Int. ed. Singapore: McGraw-Hill, 1988.

Inagaki

Fuyuto

Nishikawa

et al . Dual-fuel PCI combustion controlled by in-cylinder stratification of ignitability, SAE paper 2006-01-0028, 2006.

Hasegawa

Yanagihara

HCCI combustion in DI diesel engine. SAE paper 2003-01-0745, 2003.

Klingbeil

Juneja

et al . Premixed diesel combustion analysis in a heavy-duty diesel engine. SAE paper 2003-01-0341, 2003.

Takeda

Keiichi

Emission characteristics of premixed lean diesel combustion with extremely early staged fuel injection. SAE paper 961163, 1996.

Huang

Study of fuel distribution on diesel PCI combustion by development of a new characteristic-time combustion model. SAE paper 2008-01-1605, 2008.

Splitter

Hanson

Kokjohn

et al . Improving engine performance by optimizing fuel reactivity with a dual fuel PCCI strategy. In: Conference on thermo- and fluid dynamic processes in diesel engines, Valencia, Spain, 14–17 September 2010.

Reitz

Duraisamy

Review of high efficiency and clean reactivity controlled compression ignition (RCCI) combustion in internal combustion engines. Prog Energy Combust Sci 2015; 46: 12–71.

Splitter

Reitz

Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines. Fuel 2014; 118: 163–175.

10.

Curran

Hanson

Wagner

Effect of E85 on RCCI performance and emissions on a multi-cylinder light-duty diesel engine. SAE paper 2012-01-0376, 2012.

11.

Splitter

Wissink

Kokjohn

et al . Effect of compression ratio and piston geometry on RCCI load limits and efficiency. SAE paper 2012-01-0383, 2012.

12.

Curran

Hanson

Wagner

et al . Efficiency and emissions mapping of RCCI in a light-duty diesel engine. SAE paper 2013-01-0289, 2013.

13.

Hanson

Reitz

Investigation of combustion phasing control during reactivity controlled compression ignition (RCCI) multi-cylinder engine load transitions. J Eng Gas Turbines Power 2014; 136: 10.091511-1.

14.

Lee

Experimental study on the characteristics of dual-fuel combustion modes and extension of dual-fuel PCI operating range in a CI engine. PhD Thesis, Seoul National University, Republic of Korea, 2016.

15.

Choi

Jung

Chi

et al . Diesel/gasoline dual fuel powered combustion system based on diesel compression ignition triggered ignition control. SAE paper 2013-01-1718, 2013.

16.

Yang

Dec

Dronniou

et al . Partial fuel stratification to control HCCI heat release rates: fuel composition and other factors affecting pre-ignition reactions of two-stage ignition fuels. SAE Int J Engines 2011; 4: 1903–1920.

17.

Asad

Zheng

Exhaust gas recirculation for advanced diesel combustion cycles. Appl Energy 2014; 123: 242–252.

18.

Azimov

Tomita

Kawahara

et al . Premixed mixture ignition in the end-gas region (PREMIER) combustion in a natural gas dual-fuel engine: operating range and exhaust emissions. Int J Engine Res 2011; 12: 1–14.

19.

Herold

Krasselt

Foster

et al . Investigations into the effects of thermal and compositional stratification on HCCI combustion. Part II. Optical engine results. SAE Int J Engines 2009; 2: 1034–1053.

20.

Kokjohn

Reitz

Splitter

et al . Investigation of fuel reactivity stratification for controlling PCI heat-release rates using high-speed chemiluminescence imaging and fuel tracer fluorescence. SAE paper 2012-01-0375, 2012.