Cotton Seed FAME Combustion and Emissions Research in a DI Diesel Engine

Author(s):  
Valentin Soloiu ◽  
Jabeous Weaver ◽  
Henry Ochieng ◽  
Marvin Duggan ◽  
Sherwin Davoud ◽  
...  

This study investigates the combustion characteristics of cotton seed fatty acid methyl esters (FAME), with C100 (100% cotton seed biodiesel) and C20 (20% cotton seed biodiesel, 80% ultra-low sulfur diesel #2), in a direct injection diesel engine and compares the results with ultra-low sulfur diesel #2 (ULSD#2). The dynamic viscosity of C100 was found to meet the American Society for Testing and Materials (ASTM) standard. The lower heating value obtained for C100 was 37.7 MJ/kg, compared to 42.7 MJ/kg for ULSD#2. ULSD#2 and C100 displayed ignition delays of 9.6 crank angle degrees (CAD) and 7 CAD representing 1.14 ms and 0.83 ms respectively and a combustion time of 4ms (35 CAD) at 1400 rpm and 8 bar indicated mean effective pressure (IMEP) (100% load). The apparent heat release of the tested fuels at 8 bar IMEP showed both a premixed and diffusion phase and produced maximum values of 122 and 209 J/CAD for C100 and ULSD#2 respectively, with a decreasing trend occurring with increase in percentage of FAME. The 50% mass burnt (CA50) for 100% biodiesel was found to be 3 CAD advanced, compared with ULSD#2. The maximum total heat flux rates showed a value of 3.2 MW/m2 for ULSD#2 at 8 bar IMEP with a 6% increase observed for C100. Mechanical efficiency of ULSD#2 was 83% and presented a 5.35% decrease for C100, while the overall efficiency was 36% for ULSD#2 and 33% for C100 at 8 bar IMEP. The nitrogen oxides (NOx) for C100 presented an 11% decrease compared with ULSD#2. Unburned hydrocarbons value (UHC) for ULSD#2 was 2.8 g/kWh at 8 bar IMEP, and improved by 18% for C100. The carbon monoxide (CO) emissions for C100 decreased by 6% when compared to ULSD#2 at 3 bar IMEP but were relatively constant at 8 bar IMEP, presenting a value of 0.82 g/kWh for both fuels. The carbon dioxide (CO2) emissions for C100 increased by 1% compared with ULSD#2, at 3 bar IMEP. The soot value for ULSD#2 was 1.5 g/kWh and presented a 42% decrease for C100 at 8 bar IMEP. The results suggest a very good performance of cotton seed biodiesel, even at very high content of 100%, especially on the emissions side that showed decreasing values for regulated and non-regulated species.

Author(s):  
Valentin Soloiu ◽  
Martin Muiños ◽  
Tyler Naes ◽  
Spencer Harp ◽  
Marcis Jansons

In this study, the combustion and emissions characteristics of Reactivity Controlled Compression Ignition (RCCI) obtained by direct injection (DI) of S8 and port fuel injection (PFI) of n-butanol were compared with RCCI of ultra-low sulfur diesel #2 (ULSD#2) and PFI of n-butanol at 6 bar indicated mean effective pressure (IMEP) and 1500 rpm. S8 is a synthetic paraffinic kerosene (C6–C18) developed by Syntroleum and is derived from natural gas. S8 is a Fischer-Tropsch fuel that contains a low aromatic percentage (0.5 vol. %) and has a cetane number of 63 versus 47 of ULSD#2. Baselines of DI conventional diesel combustion (CDC), with 100% ULSD#2 and also DI of S8 were conducted. For both RCCI cases, the mass ratio of DI to PFI was set at 1:1. The ignition delay for the ULSD#2 baseline was found to be 10.9 CAD (1.21 ms) and for S8 was shorter at 10.1 CAD (1.12 ms). In RCCI, the premixed charge combustion has been split into two regions of high temperature heat release, an early one BTDC from ignition of ULSD#2 or S8, and a second stage, ATDC from n-butanol combustion. RCCI with n-butanol increased the NOx because the n-butanol contains 21% oxygen, while S8 alone produced 30% less NOx emissions when compared to the ULSD#2 baseline. The RCCI reduced soot by 80–90% (more efficient for S8). However, S8 alone showed a considerable increase in soot emissions compared with ULSD#2. The indicated thermal efficiency was the highest for the ULSD#2 and S8 baseline at 44%. The RCCI strategies showed a decrease in indicated thermal efficiency at 40% ULSD#2-RCCI and 42% and for S8-RCCI, respectively. S8 as a single fuel proved to be a very capable alternative to ULSD#2 in terms of combustion performance nevertheless, exhibited higher soot emissions that have been mitigated with the RCCI strategy without penalty in engine performance.


Author(s):  
Valentin Soloiu ◽  
Jose Moncada ◽  
Tyler Naes ◽  
Martin Muiños ◽  
Spencer Harp

This investigation focused on the combustion and performance of an indirect injection (IDI) diesel engine powered by a non-edible biodiesel blend, Brassica Carinata. This oilseed has become an attractive non-edible feedstock for biodiesel in the United States, given potential agronomical advantages. A small bore, single cylinder IDI engine was run at 2000 rpm and 5.5 bar indicated mean effective pressure (IMEP) using ultra-low sulfur diesel #2 (ULSD#2) and compared with C50, a 50% Carinata biodiesel-ULSD#2 blend (by mass). The apparent heat release for C50 reached a maximum of 22.04 J/deg which was 6.3 % lower and peaked 1.80 CAD before ULSD#2. The radiation and convection heat fluxes had similar maximum values of 0.62 MW/m2 and 1.34 MW/m2, respectively. The brake specific fuel consumption (BSFC) of C50 was 211.05 g/kWh, which was 9% higher than for ULSD#2. The mechanical efficiency was maintained relatively constant at 55% while the indicated thermal efficiency of the engine reached 59%. Both fuels produced similar nitrogen oxide (NOx) emissions with ULSD#2 and C50 producing 2.29 g/kWh and 2.23 g/kWh, respectively. The results indicate that the IDI engine can optimally work with concentrations up to 50% biodiesel.


Author(s):  
Chandrasekharan Jayakumar ◽  
Jagdish Nargunde ◽  
Anubhav Sinha ◽  
Walter Bryzik ◽  
Naeim A. Henein ◽  
...  

Concern about the depletion of petroleum reserves, rising prices of conventional fuels, security of supply and global warming have driven research toward the development of renewable fuels for use in diesel engines. These fuels have different physical and chemical properties that affect the diesel combustion process. This paper compares between the autoignition, combustion, performance and emissions of soybean derived biodiesel, JP-8 and ultra low sulfur diesel (ULSD) in a high speed single-cylinder research diesel engine equipped with a common rail injection system. Tests were conducted at steady state conditions at different injection pressures ranging from 600 bar to 1200 bar. The ‘rate of heat release’ traces are analyzed to determine the effect of fuel properties on the ignition delay, premixed combustion fraction and mixing and diffusion controlled combustion fractions. Biodiesel produced the largest diffusion controlled combustion fraction at all injection pressures compared to ULSD and JP-8. At 600 bar injection pressure, the diffusion controlled combustion fraction for biodiesel was 53% whereas both JP-8 and ULSD produced 39%. In addition, the effect of fuel properties on engine performance, fuel economy, and engine-out emissions is determined. On an average JP-8 produced 3% higher thermal efficiency than ULSD. Special attention is given to the NOx emissions and particulate matter characteristics. On an average biodiesel produced 37% less NOx emissions compared to ULSD and JP-8.


Author(s):  
Shyamsundar Rajaraman ◽  
G. K. Yashwanth ◽  
T. Rajan ◽  
R. Siva Kumaran ◽  
P. Raghu

World at present is confronted with the twin crisis of fossil fuel depletion and environmental pollution. Rapid escalation in prices and hydrocarbon resources depletion has led us to look for alternative fuels, which can satisfy ever increasing demands of energy as well as protect the environment from noxious pollutants. In this direction an attempt has been made to study a biodiesel, namely Moringa Oil Methyl Esters [MOME]. All the experiments were carried out on a 4.4 kW naturally aspirated stationary direct injection diesel engine coupled with a dynamometer to determine the engine performance and emission analysis for MOME. It was observed that there was a reduction in HC, CO and PM emissions along with a substantial increase in NOx. MOME and its blends had slightly lower thermal efficiency than diesel oil.


2019 ◽  
Vol 895 ◽  
pp. 139-143
Author(s):  
A. Anand ◽  
B.S. Nithyananda ◽  
G.V. Naveen Prakash

India is a fastest growing major economy in 2018, with a growth rate of 7.4 per cent GDP. Energy use in developing countries like India has risen more than fourfold over the past three decades and is expected to continue increasing rapidly in the future. Energy is essential for a economical growth of any county. Biofuels derived from renewable resources will become a alternative supplement for the conventional energy sources in meeting the increasing requirements for transportation fuels. In the present paper, effort are made to evaluate the pongamia biodiesel of 20% Blend (PB20) with neat diesel as an alternative fuel for CI engine. The pongamia oil is converted into pongamia methyl esters (Biodiesel) using two step process Esterification and Transesterification. The fuel properties of raw pongamia methyl ester and blend (PB20) are evaluated as per ASTM/BIS standards to check their feasibility as an alternative fuel. The prepared blend is used to run the computerized CRDI diesel engine at different load conditions. From the experimental investigation made, PB20 has a potential to be as an alternative fuel for diesel engine. The performance of PB20 with respect to Brake Thermal Efficiency (BTHE), Mechanical Efficiency, Brake Mean Effective Pressure (BMEP) and Specific Fuel Consumption (SFC) is comparatively low when compared to neat diesel. The P-Ɵ and P-V diagram shows that the combustion of PB20 is as similar to that of neat diesel.


Author(s):  
Valentin Soloiu ◽  
Jose Moncada ◽  
Martin Muiños ◽  
Remi Gaubert ◽  
Johnnie Williams ◽  
...  

Performance of an experimental diesel engine was investigated when fueled with CTL20 (80% ULSD#2 (ultra-low sulfur diesel) blended with 20% Fischer-Tropsch coal-to-liquid (CTL) fuel. CTL fuel was selected given its potential as an alternative fuel that can supplement the ULSD supply. Combustion and emissions were studied in a common rail, supercharged, single cylinder DI engine with 15% exhaust gas recirculation operated at 1500 RPM and 4.5 bar IMEP in reference to a diesel baseline. The injection pressure was varied from 800–1200 bar while injection timing was tested from 15° to 22° CAD BTDC to optimize combustion. Similar in-cylinder pressures and temperatures were observed for both fuels at the same injection pressure and timing; the maximum heat release and in cylinder pressure and temperatures increased with higher rail pressure. CTL20 had a retarded premixed burn peak by 5 to 8 J/CAD compared to diesel at the same injection pressure and timing. This can be related to a delayed ignition of CTL20 which allowed for higher peak premixed combustion. In-cylinder convection and radiation heat fluxes were stable across injection pressures for both fuels around 1.7 MW/m2 and 0.4 MW/m2, respectively. NOx decreased with CTL20 at higher injection pressure while soot was relatively increased at lower injection pressure. CTL20 decreased BSFC by 3–5% compared to ULSD#2 at 800–1200 bar injection. The mechanical efficiency was maintained around 65% for ULSD#2 as well as for CTL20 during operation at all injection pressures. The study suggests that CTL fuel can be used at 20% as a binary mixture in ULSD#2 while sustaining performance in the experimental engine.


Author(s):  
Valentin Soloiu ◽  
Jose Moncada ◽  
Remi Gaubert ◽  
Spencer Harp ◽  
Kyle Flowers ◽  
...  

Jet-A was investigated in RCCI (Reactivity Controlled Compression Ignition) given that the fuel is readily available and has a similar cetane number compared to ultra-low sulfur diesel (ULSD#2). To promote emissions’ control, RCCI was conducted with direct injection (DI) of Jet-A and PFI (port fuel injection) of n-butanol. Combustion and emission characteristics of Jet-A RCCI were investigated for a medium duty DI experimental engine operated at constant boost and 30% EGR rate and compared to ULSD#2 RCCI and single-fuel ULSD#2 operation. DI fuel was injected at 5 CAD ATDC and constant rail pressure of 1500 bar. A 20% pilot by mass was added and investigated at timings from 15 to 5 CAD BTDC for combustion stability. The results showed that the effect of the pilot injection on Jet-A combustion was not as prominent as compared to that of ULSD#2, suggesting a slightly different spray and mixture formation. Ignition delay for Jet-A was 15–20% shorter compared to ULSD#2 in RCCI. When the pilot was set to 5 CAD BTDC, CA50 phased for ULSD#2 RCCI by 3 CAD later when compared to Jet-A RCCI. After TDC, the local pressure maximum for ULSD#2 RCCI decreased by 3 bar, resulting from a 15% difference in peak heat release rate between ULSD#2 and Jet-A in RCCI at the same pilot timing. NOx and soot levels were reduced by a respective maximum of 35% and 80% simultaneously in Jet-A RCCI mode compared to single-fuel ULSD#2, yet, were higher compared to ULSD#2 RCCI. Ringing intensity was maintained at similar levels and energy specific fuel consumption (ESFC) improved by at least 15% for Jet-A compared to ULSD#2 in RCCI. Mechanical efficiencies additionally improved at earlier pilot timing by 2%. In summary, Jet-A RCCI allowed for emissions control and increased fuel efficiencies compared to single fuel ULSD#2, however, injection should be further tweaked in order to reach lower soot levels.


Author(s):  
Valentin Soloiu ◽  
Jabeous Weaver ◽  
Marvin Duggan ◽  
Henry Ochieng ◽  
Brian Vlcek ◽  
...  

This study investigates the combustion characteristics of methyl oleate (oleic FAME) produced from oleic acid. This compound is the main fatty acid component of peanut FAME, a potential renewable biofuel. Methyl oleate has been suggested in our previous work as a reference fuel or surrogate for biodiesel for advanced research (simulation and experiments), or as an enrichment compound to improve biodiesel’s fuel properties. This investigation compares the combustion and emissions characteristics of methyl oleate to peanut FAME and ultra-low sulfur diesel No. 2 (ULSD), in a single-cylinder indirect injection diesel engine intended for use as an auxiliary power unit. The dynamic viscosity of peanut FAME (P100) and Methyl Oleate (O100) was found to be 5.2 cP and 4.3 cP, respectively, at 40°C. It was determined from the ASTM standards for biodiesel that up to 50% FAME could be run in the engine. The lower heating value of P100 and O100 was 36 MJ/kg and 37 MJ/kg respectively, compared to 42.7MJ/kg for ULSD. With a combustion time of 2ms, P50 and O50 have shown similar combustion characteristics with ignition delays of about 1 ms at 2200rpm, 6.2 imep (100% load). The P50, O50, and ULSD heat release, with premixed phase combining with diffusion combustion, produced maximum values of 20.3 J/CAD, 22.7 J/CAD, and 21.9 J/CAD respectively. The heat fluxes were calculated by the Annand model, and a 2% increase in maximum total heat flux was observed for O50 compared with a maximum value of 1.95 MW/m2 for ULSD and P50. The mechanical efficiency of 77% was similar for all tested FAME blends and ULSD. The NOx increased for P20 by 6% compared with ULSD while for P50 it was similar to the ULSD values. The NOx emissions of methyl oleate showed a similar trend with that of ULSD. The soot values were relatively constant for all of the methyl oleate blends and increased by 14% for P50 when comparing both fuels to ULSD. The findings support the use of methyl oleate as a reference or model fuel for combustion modeling, and as a compound for enriching biodiesel.


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