Low Temperature Combustion Optimization and Cycle-by-Cycle Variability Through Injection Optimization and Gas-to-Liquid Fuel-Blend Ratio

2013 ◽  
Vol 135 (7) ◽  
Author(s):  
A. D. Michailidis ◽  
R. K. Stobart ◽  
G. P. McTaggart-Cowan
Keyword(s):  
Low Temperature ◽  
Fuel Efficiency ◽  
Cyclic Behavior ◽  
Diesel Combustion ◽  
Low Temperature Combustion ◽  
Cylinder Pressure ◽  
Split Injection ◽  
Blend Ratio ◽  
Temperature Combustion ◽  
The Mean

The advent of common rail technology alongside powerful control systems capable of delivering multiple accurate fuel charges during a single engine cycle has revolutionized the level of control possible in diesel combustion. This technology has opened a new path enabling low-temperature combustion (LTC) to become a viable combustion strategy. The aim of the research work presented within this paper is the understanding of how various engine parameters of LTC optimize the combustion both in terms of emissions and in terms of fuel efficiency. The work continues with an investigation of in-cylinder pressure and IMEP cycle-by-cycle variation. Attention will be given to how repeatability changes throughout the combustion cycle, identifying which parts within the cycle are least likely to follow the mean trend and why. Experiments were conducted on a single-cylinder 510cc boosted diesel engine. LTC was affected over varying rail pressure and combustion phasing. Single and split injection regimes of varying dwell-times were investigated. All injection conditions were phased across several crank-angles to demonstrate the interaction between emissions and efficiency. These tests were then repeated with blends of 30% and 50% gas-to-liquid (GTL)-diesel blends in order to determine whether there is any change in the trends of repeatability and variance with increasing GTL blend ratio. The experiments were evaluated in terms of emissions, fuel efficiency, and cyclic behavior. Specific attention was given to how the NOx–PM trade-off changes through increased injection complexity and increasing GTL blend ratio. The cyclic behavior was analyzed in terms of in-cylinder pressure standard deviation. This gives a behavior profile of the repeatability of in-cylinder pressure in comparison to the mean. Each condition was then compared to the behavior of equivalent injection conditions in conventional diesel combustion. Short-dwell split injection was shown to be beneficial for LTC, while NOx was shown to be reduced by the substitution of GTL in the fuel. In-cylinder pressure cyclic behavior was also shown to be comparable or superior to conventional combustion in every case examined. GTL improved this further, but not in proportion to its blend ratio.

Cost Effective BS-VI Solution - A Combined Low Temperature Combustion and Conventional Diesel Combustion Concepts

2019 ◽  
Author(s):  
Simhachalam Juttu ◽  
Sanjeev Gothekar ◽  
Neelkanth V Marathe ◽  
Nagesh Harishchandra Walke ◽  
Subhanker Dev
Keyword(s):  
Low Temperature ◽  
Cost Effective ◽  
Diesel Combustion ◽  
Low Temperature Combustion ◽  
Temperature Combustion

Soot Emissions of Various Oxygenated Biofuels in Conventional Diesel Combustion and Low-Temperature Combustion Conditions

2012 ◽  
Vol 26 (3) ◽  
pp. 1900-1911 ◽  
Author(s):  
Haifeng Liu ◽  
Xiaojie Bi ◽  
Ming Huo ◽  
Chia-fon F. Lee ◽  
Mingfa Yao
Keyword(s):  
Low Temperature ◽  
Diesel Combustion ◽  
Low Temperature Combustion ◽  
Temperature Combustion ◽  
Soot Emissions

An Experimental Investigation on the Effect of Post-Injection Strategies on Combustion and Emissions in the Low-Temperature Diesel Combustion Regime

2005 ◽  
Vol 129 (1) ◽  
pp. 279-286 ◽  
Author(s):  
Hanho Yun ◽  
Rolf D. Reitz
Keyword(s):  
Low Temperature ◽  
Soot Formation ◽  
Combustion Regime ◽  
Nox Emissions ◽  
Diesel Combustion ◽  
Low Temperature Combustion ◽  
Post Injection ◽  
Temperature Combustion ◽  
Soot Emissions ◽  
Injection Strategies

In order to meet future emissions regulations, new combustion concepts are being developed. Among them, the development of low-temperature diesel combustion systems has received considerable attention. Low NOx emissions are achieved through minimization of peak temperatures during the combustion process. Concurrently, soot formation is inhibited due to a combination of low combustion temperatures and extensive fuel-air premixing. In this study, the effect of late-cycle mixing enhancement by post-injection strategies on combustion and engine-out emissions in the low-temperature (low soot and NOx emissions) combustion regime was experimentally investigated. The baseline operating condition considered for low-temperature combustion was 1500rpm, 3bar IMEP with 50% EGR rate, and extension to high loads was considered by means of post injection. Post-injection strategies gave very favorable emission results in the low-temperature combustion regime at all loads tested in this study. Since post injection leads to late-cycle mixing improvement, further reductions in soot emissions were achieved without deteriorating the NOx emissions. With smaller fuel injected amounts for the second pulse, better soot emissions were found. However, the determination of the dwell between the injections was found to be very important for the emissions.

An Experimental and Numerical Investigation on the Effect of Post Injection Strategies on Combustion and Emissions in the Low-Temperature Diesel Combustion Regime

2005 ◽  
Author(s):  
Hanho Yun ◽  
Yong Sun ◽  
Rolf D. Reitz
Keyword(s):  
Low Temperature ◽  
Soot Formation ◽  
Combustion Regime ◽  
Nox Emissions ◽  
Diesel Combustion ◽  
Low Temperature Combustion ◽  
Post Injection ◽  
Temperature Combustion ◽  
Soot Emissions ◽  
Injection Strategies

In order to meet future emissions regulations, new combustion concepts are being developed. Among them, the development of low-temperature diesel combustion systems has received considerable attention. Low NOx emissions are achieved through minimization of peak temperatures occurring during the combustion process. Concurrently, soot formation is inhibited due to a combination of low combustion temperatures and extensive fuel-air pre-mixing. In this study, the effect of late-cycle mixing enhancement by post injection strategies on combustion and engine-out emissions in the low-temperature combustion regime was investigated experimentally and numerically. The baseline operating condition considered for low-temperature combustion was 1500 rev/min, 3bar IMEP with 50% EGR rate, and extension to high loads was considered by means of post injection. Post injection strategies gave very favorable emission results in the low temperature combustion regime at all loads. With small second fuel injected amounts, better soot emissions were found. However, the determination of the dwell between the injections was found to be very important for the emissions. Since post injection leads to late-cycle mixing improvement, further reductions in soot emissions were achieved without deteriorating the NOx emissions. To explain these results, numerical analysis was also done using the KIVA-CHEMKIN code. The simulations show that optimal combustion requires that the post injection fuel avoid fuel rich regions formed from the main injection.

An Experimental Investigation of Low-Octane Gasoline in Diesel Engines

2011 ◽  
Vol 133 (9) ◽  
Author(s):  
Stephen Ciatti ◽  
Swami Nathan Subramanian
Keyword(s):  
Low Temperature ◽  
Fuel Efficiency ◽  
Nox Emissions ◽  
Low Temperature Combustion ◽  
Compression Ignition ◽  
Oxides Of Nitrogen ◽  
Conventional Combustion ◽  
Compression Ignition Engines ◽  
Temperature Combustion ◽  
Power Densities

Conventional combustion techniques struggle to meet the current emissions norms. In particular, oxides of nitrogen (NOx) and particulate matter (PM) emissions have limited the utilization of diesel fuel in compression ignition engines. Advance combustion concepts have proved the potential to combine fuel efficiency and improved emission performance. Low-temperature combustion (LTC) offers reduced NOx and PM emissions with comparable modern diesel engine efficiencies. The ability of premixed, low-temperature compression ignition to deliver low PM and NOx emissions is dependent on achieving optimal combustion phasing. Diesel operated LTC is limited by early knocking combustion, whereas conventional gasoline operated LTC is limited by misfiring. So the concept of using an unconventional fuel with the properties in between those two boundary fuels has been experimented in this paper. Low-octane (84 RON) gasoline has shown comparable diesel efficiencies with the lowest NOx emissions at reasonable high power densities (NOx emission was 1 g/kW h at 12 bar BMEP and 2750 rpm).

An Experimental Investigation of Low Octane Gasoline in Diesel Engines

2010 ◽  
Author(s):  
Stephen Ciatti ◽  
Swami Nathan Subramanian
Keyword(s):  
Low Temperature ◽  
Fuel Efficiency ◽  
Nox Emissions ◽  
Low Temperature Combustion ◽  
Compression Ignition ◽  
Oxides Of Nitrogen ◽  
Conventional Combustion ◽  
Compression Ignition Engines ◽  
Temperature Combustion ◽  
Power Densities

Conventional combustion techniques struggle to meet the current emissions norms. In particular, oxides of nitrogen (NOx) and particulate matter (PM) emissions have limited the utilization of diesel fuel in compression ignition engines. Advance combustion concepts have proved the potential to combine fuel efficiency and improved emissions performance. Low Temperature Combustion (LTC) offers reduced NOx and PM emissions with comparable modern diesel engine efficiencies. The ability of premixed, low-temperature compression ignition to deliver low PM and NOx emissions is dependent on achieving optimal combustion phasing. Diesel operated LTC is limited by early knocking combustion whereas conventional gasoline operated LTC is limited by misfiring. So the concept of using an unconventional fuel with the properties in between those two boundary fuels has been experimented in this paper. Low octane (84 RON) gasoline has shown comparable diesel efficiencies with lowest NOx emissions at reasonable high power densities (NOx emission were 1 g/kW-hr at 12 bar BMEP and 2750 rpm).

Low Temperature Combustion (LTC) Optimization and Cycle-by-Cycle Variability Through Injection Optimization and Gas-to-Liquid (GTL) Fuel-Blend Ratio

2012 ◽  
Author(s):  
A. D. Michailidis ◽  
R. K. Stobart ◽  
G. P. McTaggart-Cowan
Keyword(s):  
Low Temperature ◽  
Research Work ◽  
Combustion Process ◽  
Low Temperature Combustion ◽  
Compression Ignition ◽  
Fuel Blend ◽  
Blend Ratio ◽  
Temperature Combustion ◽  
Gas To Liquid ◽  
Combustion Cycle

The advent of common rail technology alongside powerful control systems capable of delivering multiple accurate fuel charges during a single engine cycle has revolutionized the level of control possible in diesel combustion. This technology has opened a new path enabling low-temperature combustion (LTC) to become a viable combustion strategy. The aim of the research work presented within this paper is the understanding of how various engine parameters of LTC optimize the combustion both in terms of emissions and in terms of fuel efficiency. The work continues with an investigation of in-cylinder pressure and IMEP cycle-by-cycle variation. Attention will be given to how repeatability changes throughout the combustion cycle, identifying which parts within the cycle are least likely to follow the mean trend and why. Experiments were formulated to include rail pressure, injection settings of single injection and split-injection of varying dwell times. All injection conditions were phased across several crank-angles to demonstrate the interaction between emissions and efficiency. These tests are then repeated with blends of 30% and 50% gas-to-liquid (GTL)-Diesel blends in order to determine whether there is any change in the trends of repeatability and variance with increasing GTL blend ratio. Compression-ignition has been traditionally regarded as sufficiently stable that such investigation is irrelevant. Major improvements have been made, however, both to the understanding of compression-ignition and its control. Re-assessing and investigating how pressure repeatability fluctuates over the combustion cycle, especially in atypical engine conditions will help our understanding of combustion and facilitate a more accurate optimization of the combustion process.

Sign in / Sign up

Export Citation Format

Share Document