The Impact of RON on SI Engine Thermal Efficiency

Nakata, Kohei; Uchida, Daisuke; Ota, Atsuharu; Utsumi, Shintaro; Kawatake, Katsunori

doi:10.4271/2007-01-2007

Cited by 45 publications

(17 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This enables some of the power density and efficiency losses from spark retard and PE to be reduced. These include cooled EGR, [12,13] cooled EGR with hydrogen addition to improve dilution tolerance [14] and the use of an Atkinson cycle (LIVC) to reduce the effective compression ratio to limit knock [15]. Lean boosted systems have also been evaluated with E85 to improve efficiency [15].…”

Section: Figure 1 Ethanol Production and Targets As Outline By The Ementioning

confidence: 99%

“…These include cooled EGR, [12,13] cooled EGR with hydrogen addition to improve dilution tolerance [14] and the use of an Atkinson cycle (LIVC) to reduce the effective compression ratio to limit knock [15]. Lean boosted systems have also been evaluated with E85 to improve efficiency [15]. The use of a duel fuel system with gasoline Port Fuel Injection (PFI) and DI E85 has demonstrated the ability to leverage E85 for high load efficient operation while providing increased efficiency with gasoline at low loads [4].…”

Section: Figure 1 Ethanol Production and Targets As Outline By The Ementioning

confidence: 99%

See 1 more Smart Citation

Engine Efficiency Improvements Enabled by Ethanol Fuel Blends in a GDi VVA Flex Fuel Engine

Moore¹,

Foster²,

Hoyer³

2011

SAE Technical Paper Series

View full text Add to dashboard Cite

Advances in engine technology including Gasoline Direct injection (GDi), Dual Independent Cam Phasing (DICP), advanced valvetrain and boosting have allowed the simultaneous reductions of fuel consumption and emissions with increased engine power density. The utilization of fuels containing ethanol provides additional improvements in power density and potential for lower emissions due to the high octane rating and evaporative cooling of ethanol in the fuel. In this paper results are presented from a flexible fuel engine capable of operating with blends from E0-E85. The increased geometric compression ratio, (from 9.2 to 11.85) can be reduced to a lower effective compression ratio using advanced valvetrain operating on an Early Intake Valve Closing (EIVC) or Late Intake Valve Closing (LIVC) strategy. DICP with a high authority intake phaser is used to enable compression ratio management. The advanced valvetrain also provides significantly reduced throttling losses by efficient control of intake air and residuals. Increased ethanol blends provide improvements in power density due to knock resistance. Knock resistance also provides a significant potential for reduced NOx since higher dilution without knock is enabled at moderate loads typical of normal driving. E85 also shows significant advantages for particulate emissions that enable broader authority in selection of optimal injection timings for improving efficiency. An increase in the ethanol content improves low end torque providing an addition opportunity for improved fuel economy by using down-speeding for more efficient vehicle operation

show abstract

Section: Figure 1 Ethanol Production and Targets As Outline By The Ementioning

confidence: 99%

Section: Figure 1 Ethanol Production and Targets As Outline By The Ementioning

confidence: 99%

Engine Efficiency Improvements Enabled by Ethanol Fuel Blends in a GDi VVA Flex Fuel Engine

Moore¹,

Foster²,

Hoyer³

2011

SAE Technical Paper Series

View full text Add to dashboard Cite

show abstract

“…Muñoz et al (2005) estimated an improvement of about 3% in an engine's efficiency as its compression ratio increases by one point. Nakata et al (2007) found that, at partial load, the thermal efficiency of a lean boosted engine can be improved from 35% to 39% by increasing the compression ratio from 10 to 13 with 92 RON gasoline, and it can be further improved to 41.9% (i.e., by 7.4%) at a compression ratio of 13 when RON is raised from 92 to 100. However, it is important to note that the improvement might not be realized for highly loaded cycles, such as U.S. driving cycles.…”

Section: Vehicle Efficiency Gainsmentioning

confidence: 89%

“…According to several previous studies, use of 100 RON gasoline with mid-level ethanol in the blend can be leveraged to improve engine efficiency (as defined by fuel consumption for given loads) significantly Hirshfeld et al, 2014;Kalghatgi, 2001;Leone et al, 2014;Mittal and Heywood, 2009;Muñoz et al, 2005;Nakata et al, 2007;Speth et al, 2014;Stein et al, 2012). However, the inclusion of high volumes of ethanol in the gasoline pool represents a redistribution of intermediate gasoline blendstocks to achieve fuel specifications.…”

Section: Ron and Rvp Specificationsmentioning

confidence: 99%

Environmental, Economic, and Scalability Considerations and Trends of Selected Fuel Economy-Enhancing Biomass-Derived Blendstocks

Dunn

Biddy

Jones

et al. 2017

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Twenty-four biomass-derived compounds and mixtures, identified based on their physical properties, which could be blended into fuels to improve spark ignition engine fuel economy, were assessed for their economic, technology readiness, and environmental viability. These bio-blendstocks were modeled to be produced biochemically, thermochemically, or through hybrid processes. To carry out the assessment, 17 metrics were developed for which each bio-blendstock was determined to be favorable, neutral, or unfavorable. Cellulosic ethanol was included as a reference case. Overall economic and, to some extent, environmental viability is driven by projected yields for each of these processes. The metrics used in this analysis methodology highlight the near-term potential to achieve these targeted yield estimates when considering data quality and current technical readiness for these conversion strategies. Key knowledge gaps included the degree of purity needed for use as a bio-blendstock. Less stringent purification requirements for fuels could cut processing costs and environmental impacts. Additionally, more information is needed on the blending behavior of many of these bio-blendstocks with gasoline to support the technology readiness evaluation. Overall, the technology to produce many of these blendstocks from biomass is emerging, and as it matures, these assessments must be revisited. Importantly, considering economic, environmental, and technology readiness factors, in addition to physical properties of blendstocks that could be used to boost engine efficiency and fuel economy, in the early stages of project research and development can help spotlight those most likely to be viable in the near term.

show abstract

“…In engines, one effective way is to improve the engine thermal efficiency. High-compression-ratio engines [1] and lean boosted engines [2] have the potential to achieve high thermal efficiency [3]. Knock, however, does not allow for high thermal efficiency.…”

Section: Introductionmentioning

confidence: 99%

The effect of fuel properties on thermal efficiency of advanced spark-ignition engines

Nakata

Sasaki

Ota

et al. 2011

International Journal of Engine Research

View full text Add to dashboard Cite

Owing to issues of global warming and energy security, improving engine thermal efficiency has become increasingly important today. This paper investigates the impact of high-research-octane-number (RON) fuels on engine thermal efficiency. It is shown that the lean boosted engine has higher potential to increase engine thermal efficiency than naturally aspirated (NA) engines and the combination of lean boosted engine and high-RON fuels gives around 44 per cent engine thermal efficiency. The engine thermal efficiency exceeds a diesel engine's thermal efficiency. Therefore, the combination is expected to be an effective way to reduce CO 2 emissions in the future. In this paper, the high-RON fuels are blended with gasoline components or bio-components. This paper also describes the combustion characteristics of ethanol and butanol. These fuels have good combustion features after the engine has warmed up. However, it is found that butanol gives more severe combustion characteristics under cold conditions.

show abstract

The Impact of RON on SI Engine Thermal Efficiency

Cited by 45 publications

References 6 publications

Engine Efficiency Improvements Enabled by Ethanol Fuel Blends in a GDi VVA Flex Fuel Engine

Engine Efficiency Improvements Enabled by Ethanol Fuel Blends in a GDi VVA Flex Fuel Engine

Environmental, Economic, and Scalability Considerations and Trends of Selected Fuel Economy-Enhancing Biomass-Derived Blendstocks

The effect of fuel properties on thermal efficiency of advanced spark-ignition engines

Contact Info

Product

Resources

About