Particulate Matter Emissions From Late Injection High EGR Low Temperature Diesel Combustion

2011 ◽  
Author(s):  
Brandon T. Tompkins ◽  
Hoseok Song ◽  
Timothy J. Jacobs
Keyword(s):  
Particulate Matter ◽  
Low Temperature ◽  
Direct Injection ◽  
Injection Timing ◽  
Low Temperature Combustion ◽  
No Formation ◽  
Fuel Flow ◽  
Particulate Matter Emissions ◽  
Temperature Combustion ◽  
Gas Recirculation

Low temperature combustion (LTC) is an advanced mode of combustion that has attained much attention due to ever increasing emission standards. LTC simultaneously reduces soot and nitric oxide (NO) emissions by having combustion take place at, for example bulk gas temperatures below 1200K (as observed in this study) so that soot and NO formation is substantially reduced. Soot is typically considered a building block for particulate matter (PM); both PM and NO are heavily regulated emissions by government agencies due to their potential effects on human and environmental health. Although LTC is believed to substantially reduce soot, it is not clear what is the end effect on PM. Because PM is composed of other agents, such as condensed liquid and solid hydrocarbons, there could potentially be non-negligible emission of PM from LTC combustion. This study will compare the gravimetric-based PM data from 3 different modes of combustion in a direct injection diesel engine; specifically: conventional combustion, combustion with high exhaust gas recirculation (EGR) at conventional injection timing, and combustion with high EGR and late injection timing (all other control parameters are the same, including fuel flow rate and engine speed). The objective of this study is to quantify PM emissions of LTC and assess potential differences relative to the soot concentration (the latter as assessed by a smokemeter). PM is gravimetrically measured using a mini-dilution tunnel. Further, chemical analysis of the collected PM is analyzed by an independent laboratory to develop an understanding of the constituent species composing conventional and LTC PM. PM results show that there are differences among the three modes of combustion. The PM differs in appearance as well as composition, and due to the change in appearance FSN may not correlate with PM when running LTC modes of combustion.

An Enabling Study of Low Temperature Combustion With Ethanol in a Diesel Engine

2013 ◽  
Vol 135 (4) ◽  
Author(s):  
Tongyang Gao ◽  
Prasad Divekar ◽  
Usman Asad ◽  
Xiaoye Han ◽  
Graham T. Reader ◽  
...  
Keyword(s):  
Low Temperature ◽  
Direct Injection ◽  
Empirical Work ◽  
Low Temperature Combustion ◽  
Engine Emissions ◽  
Engine Efficiency ◽  
Temperature Combustion ◽  
Charge Cooling ◽  
Gas Recirculation ◽  
Low Nitrogen

Previous research indicates that the low temperature combustion (LTC) is capable of producing ultra-low nitrogen oxides (NOx) and soot emissions. The LTC in diesel engines can be enabled by the use of heavy exhaust gas recirculation (EGR) at moderate engine loads. However, when operating at higher engine loads, elevated demands of both intake boost and EGR levels to ensure ultra-low emissions make engine controllability a challenging task. In this work, a multifuel combustion strategy is implemented to improve the emission performance and engine controllability at higher engine loads. The port fueling of ethanol is ignited by the direct injection of diesel fuel. The ethanol impacts on the engine emissions, ignition delay, heat-release shaping, and cylinder-charge cooling have been empirically analyzed with the sweeps of different ethanol-to-diesel ratios. Zero-dimensional phenomenological engine cycle simulations have been conducted to supplement the empirical work. The multifuel combustion of ethanol and diesel produces lower emissions of NOx and soot while maintaining the engine efficiency. The experimental setup and study cases are described, and the potential for the application of an ethanol-to-diesel multifuel system at higher loads has been proposed and discussed.

An Enabling Study of Low Temperature Combustion With Ethanol in a Diesel Engine

2012 ◽  
Author(s):  
Tongyang Gao ◽  
Prasad Divekar ◽  
Usman Asad ◽  
Xiaoye Han ◽  
Graham T. Reader ◽  
...  
Keyword(s):  
Low Temperature ◽  
Direct Injection ◽  
Empirical Work ◽  
Fuel Combustion ◽  
Low Temperature Combustion ◽  
Engine Emissions ◽  
Temperature Combustion ◽  
Charge Cooling ◽  
Set Up ◽  
Gas Recirculation

Previous research indicates that the low temperature combustion (LTC) is capable of producing ultra-low nitrogen oxides (NOx) and soot emissions. The LTC in diesel engines can be enabled by the heavy use of exhaust gas recirculation (EGR) at moderate engine loads. However, when operating at higher engine loads, elevated demands of both intake boost and EGR levels to ensure ultra-low emissions make engine controllability a challenging task. In this work, a multi-fuel combustion strategy is implemented to improve the emission performance and engine controllability at higher engine loads. The port fueling of ethanol is ignited by the direct injection of diesel fuel. The ethanol impacts on the engine emissions, ignition delay, heat-release shaping and cylinder-charge cooling have been empirically analyzed with the sweeps of different ethanol-to-diesel ratios. Zero-dimensional phenomenological engine cycle simulations have been conducted to supplement the empirical work. The multi-fuel combustion of ethanol and diesel produces lower emissions of NOx and soot while maintaining the engine efficiency. The experimental set-up and study cases are described and the potential for the application of ethanol-to-diesel multi-fuel system at higher loads has been proposed and discussed.

scholarly journals Simultaneous particulate matter and nitrogen oxide emission reduction through enhanced charge homogenization in diesel engines

2018 ◽  
Vol 22 (5) ◽  
pp. 2039-2052 ◽  
Author(s):  
Urban Zvar-Baskovic ◽  
Rok Vihar ◽  
Samuel Rodman-Opresnik ◽  
Tomaz Katrasnik
Keyword(s):  
Particulate Matter ◽  
Low Temperature ◽  
Diesel Fuel ◽  
Minor Effect ◽  
Exhaust Gas ◽  
Low Temperature Combustion ◽  
Engine Control ◽  
Pyrolysis Oil ◽  
Trade Off ◽  
Temperature Combustion

In the presented study, low temperature combustion was established with a direct injection of diesel fuel being a representative of high reactivity fuels and tire pyrolysis oil being a representative of low reactivity fuels. Tire pyrolysis oil was tested as a potential waste derived fuel for low temperature combustion, as it features diesel-like physical properties and lower cetane number compared to diesel fuel. The goal of this study was determination of suitable injection strategies and exhaust gas re-circulation rates to explore potentials of both fuels in reducing emissions in low temperature combustion modes. It was demonstrated that relatively small changes in the engine control strategy possess the potential to significantly improve NOx/particulate matter trade-off with minor effect on engine efficiency. In addition, low temperature combustion was for the first time successfully demonstrated with tire pyrolysis oil fuel, however, it was shown that lower re-activity of the fuel is by itself not sufficient to improve NOx /soot trade-off compared to the diesel fuel as entire spectra of fuel properties play an important role in improving NOx /soot trade-off. This study thus establishes relations between different engine control strategies, intake manifold pressure and exhaust gas recirculation rate on engine thermodynamic parameters and engine-out emissions while utilizing innovative waste derived fuel that have not yet been analysed in similar combustion concepts.

Comparison of Filter Smoke Number and Elemental Carbon Mass From Partially Premixed Low Temperature Combustion in a Direct-Injection Diesel Engine

2011 ◽  
Vol 133 (10) ◽  
Author(s):  
William F. Northrop ◽  
Stanislav V. Bohac ◽  
Jo-Yu Chin ◽  
Dennis N. Assanis
Keyword(s):  
Diesel Engine ◽  
Low Temperature ◽  
Elemental Carbon ◽  
Direct Injection ◽  
Low Temperature Combustion ◽  
Soot Mass ◽  
Temperature Combustion ◽  
Carbon Mass ◽  
Partially Premixed ◽  
Premixed Low Temperature Combustion

Partially premixed low temperature combustion (LTC) is an established advanced engine strategy that enables the simultaneous reduction of soot and NOx emissions in diesel engines. Measuring extremely low levels of soot emissions achievable with LTC modes using a filter smoke meter requires large sample volumes and repeated measurements to achieve the desired data precision and accuracy. Even taking such measures, doubt exists as to whether filter smoke number (FSN) accurately represents the actual smoke emissions emitted from such low soot conditions. The use of alternative fuels such as biodiesel also compounds efforts to accurately report soot emissions since the reflectivity of high levels of organic matter found on the particulate matter collected may result in erroneous readings from the optical detector. Using FSN, it is desired to report mass emissions of soot using empirical correlations derived for use with petroleum diesel fuels and conventional modes of combustion. The work presented in this paper compares the experimental results of well known formulas for calculating the mass of soot using FSN and the elemental carbon mass using thermal optical analysis (TOA) over a range of operating conditions and fuels from a four-cylinder direct-injection passenger car diesel engine. The data show that the mass of soot emitted by the engine can be accurately predicted with the smoke meter method utilizing a 3000 ml sample volume over a range of FSN from 0.02 to 1.5. Soot mass exhaust concentration calculated from FSN using the best of the literature expressions and that from TOA taken over all conditions correlated linearly with a slope of 0.99 and R2 value of 0.94. A primary implication of the work is that the level of confidence in reporting the soot mass based on FSN for low soot formation regimes such as LTC is improved for both petroleum diesel and biodiesel fuels.

Sign in / Sign up

Export Citation Format

Share Document