Potential of miller timing with synthetic diesel fuels on a single cylinder heavy-duty engine

2021 ◽  
pp. 146808742110436
Author(s):  
Simon Pöllmann ◽  
Martin Härtl ◽  
Georg Wachtmeister
Keyword(s):  
Nitrogen Oxides ◽  
Diesel Fuel ◽  
High Performance ◽  
Internal Combustion Engines ◽  
Soot Formation ◽  
Cetane Number ◽  
Boost Pressure ◽  
Heavy Duty ◽  
Simultaneous Application ◽  
Single Cylinder

Upcoming emission limits such as Euro VII will make it necessary to further reduce the NOx emission level of internal combustion engines while stricter CO2 limits demand lower fuel consumption. Early closing of the intake valves (Miller timing) leads to reduced combustion temperatures due to lower effective compression ratio, and therefore lower formation and emission of nitrogen oxides. Miller timing is frequently used in gasoline engines, while in Diesel engines it competes with exhaust gas recirculation (EGR). When both measures are applied simultaneously, this may lead to increased emission of soot using standard Diesel fuel, as combustion temperature and oxygen content of the charge become too low. This work shows the investigation of different intake valve timings on an externally supercharged single-cylinder heavy-duty Diesel engine, stationary operated with hydrogenated vegetable oil (HVO), oxymethylene ether (OME), and standard Diesel fuel (DF). The synthetic fuels have a higher cetane number than DF, which supports ignition at lower temperatures. Moreover, OME has a soot-free combustion, which allows an extension of the operating limits without increased emissions. The results show that especially with Miller timing a high-performance turbocharging system is crucial, since higher boost pressure is required to compensate for the filling losses due to the earlier intake closing. The application of a high EGR rate is limited in this case, leading to a trade-off between Miller timing and EGR. All fuels show a reduction in nitrogen oxides of up to 40% with an improved efficiency of more than 3% at a typical road-load point. Measures to reduce ignition delay were found to be necessary, especially for DF. For OME, increased soot formation does not occur when combining Miller timing with low rail pressure, reduced boost pressure or EGR, which promotes simultaneous application of the measures resulting in minimized emissions of nitrogen oxides.

scholarly journals Performance Evaluation of Single Cylinder Diesel Engine Using Tyre Pyrolysis Oil (TPO) Blends

2019 ◽  
Vol 7 (2) ◽  
pp. 46-51
Author(s):  
P M Bhatt
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Internal Combustion Engines ◽  
Petroleum Products ◽  
Permissible Limit ◽  
Pyrolysis Oil ◽  
Single Cylinder ◽  
Performance And Emission ◽  
Partial Load ◽  
Alternate Fuels

Increasing industrialization and motorization led to a significant rise in demand of petroleum products. As these are the non-renewable resources, it will be troublesome to predict the availability of these resources in the future, resulting in uncertainty in its supply and price and is impacting growing economies like India importing 80% of the total demand of the petroleum products. Many attempts have been made by different researchers to find out alternate fuels for Internal Combustion engines. Many alternate fuels like Biodiesel, LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas) and Alcohol are being used nowadays by different vehicles. In this context pyrolysis of scrap tyres can be used effectively to produce oil, thereby solving the problem of waste tyre disposal. In the present study, Experimental investigations were carried out to evaluate the performance and emission characteristics of a single cylinder diesel engine fueled by TPO10, TPO15, and TPO20 at a crank angle 280 before TDC (Top Dead Centre) and injection pressure of 180 bar keeping the blend quality by controlling the density and viscosity of tyre pyrolysis oil within permissible limit of euro IV diesel requirement. The performance and emission results were analyzed and compared with that of diesel fuel operation. The results of investigations indicate that the brake thermal efficiency of the TPO - DF blend decreases by 4 to 8%. CO emissions are slightly higher but within permissible limit of euro IV emission standards. HC emissions are higher by about 40 to 60% at partial load whereas smoke opacity is lower by about 14% to 22% as compared to diesel fuel.

Formation of Nitrogen Dioxide and Formaldehyde in a Medium Duty Diesel Engine With Oxygenated Fuels

2020 ◽  
Author(s):  
Denis Notheis ◽  
Uwe Wagner ◽  
Amin Velji ◽  
Thomas Koch
Keyword(s):  
Diesel Engine ◽  
Nitrogen Oxides ◽  
Nitrogen Dioxide ◽  
Diesel Fuel ◽  
Oxygen Radicals ◽  
Injection Timing ◽  
Boost Pressure ◽  
Fuel Ratio ◽  
Oxygenated Fuels ◽  
Operating Points

Abstract For modern Diesel aftertreatment systems the ratio of nitrogen dioxide (NO2) to nitrogen oxides emissions (NOx) is of great importance for the conversion of total NOx especially at low loads and low engine out exhaust temperatures. As known from previous studies the relative air-fuel ratio and so the increase of oxygen has a major impact on the in-cylinder formation of NO2. As the focus lies mainly on increasing the relative air-fuel ratio by increasing the boost pressure the influence of bounded oxygen in oxygenated fuels is not yet fully understood and is therefore in the focus of this papers. Bounded oxygen offers the potential to release oxygen radicals, which can increase NO2 formation from nitrogen monoxide (NO) at higher pressures according to the principle of Le Chatelier. At low pressures, however, released oxygen radicals can also lead to a reduction of NO2. Additionally, concerning the in-cylinder formation of NO2, the formation of formaldehyde (HCHO) is focused in this investigation, too. Especially for the oxygenated fuel like OME3–5 which can be interpreted as a compound of formaldehyde molecules the HCHO emission might increase. Although HCHO has not yet been regulated for vehicles, its carcinogenic properties require its reduction as far as possible. In this paper, investigations are presented which were carried out on a single-cylinder Diesel engine with different oxygenated fuels such as oxymethylene ether compounds (OME3–5) and 2-ethoxyethyl ether (2-EEE) and blends of these components with conventional Diesel fuel. The relevant exhaust gas components were measured using different analysis method for high accuracy and mutual validation. To analyze the effects of the fuel composition on nitrogen dioxide and formaldehyde formation the fuels are compared with pure Diesel fuel operation. Several operating points were investigated together while varying engine parameters such as relative air-fuel ratio, EGR rate, injection timing and injection pressure in a one-factor-time parameter study. Additionally, at a low load operating point a Design of Experiments (DoE) study was done to see the statistical impact and the main influencing parameters of the formation of NO2 and HCHO. Furthermore, other typical Diesel emissions like particulates, carbon monoxide and the total nitrogen oxides are investigated and compared. The investigations show an inconsistent behavior at different operating points for NO2. In most operating points a decrease of NO2 is visible, which was attributed to a decrease of the total NOx emission. Especially at higher relative air-fuel ratios and so high charge pressures the potential of oxygenated fuels to increase the NO2 to NOx ratio becomes apparent. Due to the very low particulates emissions which can be achieved with OME3–5 fuel, no restriction on low relative air/fuel ratios and higher EGR rates regarding the particulate emissions (smoke limit) exists. The HCHO emissions show different behavior in these restriction zones. At partial load, high EGR rates and low relative air-fuel ratios, HCHO emissions increase. In contrast, when the load is increased and the stoichiometric conditions are reached, the HCHO emissions decrease.

Low NOx and Low Smoke Operation of a Diesel Engine Using Gasolinelike Fuels

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
Gautam Kalghatgi ◽  
Leif Hildingsson ◽  
Bengt Johansson
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Compression Ratio ◽  
Diesel Fuel ◽  
Ignition Delay ◽  
Cetane Number ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Single Cylinder ◽  
Intake Pressure

Much of the technology in advanced diesel engines, such as high injection pressures, is aimed at overcoming the short ignition delay of conventional diesel fuels to promote premixed combustion in order to reduce NOx and smoke. Previous work in a 2 l single-cylinder diesel engine with a compression ratio of 14 has demonstrated that gasoline fuel, because of its high ignition delay, is very beneficial for premixed compression-ignition compared with a conventional diesel fuel. We have now done similar studies in a smaller—0.537 l—single-cylinder diesel engine with a compression ratio of 15.8. The engine was run on three fuels of very different auto-ignition quality—a typical European diesel fuel with a cetane number (CN) of 56, a typical European gasoline of 95 RON and 85 MON with an estimated CN of 16 and another gasoline of 84 RON and 78 MON (estimated CN of 21). The previous results with gasoline were obtained only at 1200 rpm—here we compare the fuels also at 2000 rpm and 3000 rpm. At 1200 rpm, at low loads (∼4 bars indicated mean effective pressure (IMEP)) when smoke is negligible, NOx levels below 0.4 g/kWh can be easily attained with gasoline without using exhaust gas recirculation (EGR), while this is not possible with the 56 CN European diesel. At these loads, the maximum pressure-rise rate is also significantly lower for gasoline. At 2000 rpm, with 2 bars absolute intake pressure, NOx can be reduced below 0.4 g/kW h with negligible smoke (FSN<0.1) with gasoline between 10 bars and 12 bars IMEP using sufficient EGR, while this is not possible with the diesel fuel. At 3000 rpm, with the intake pressure at 2.4 bars absolute, NOx of 0.4 g/kW h with negligible smoke was attainable with gasoline at 13 bars IMEP. Hydrocarbon and CO emissions are higher for gasoline and will require after-treatment. High peak heat release rates can be alleviated using multiple injections. Large amounts of gasoline, unlike diesel, can be injected very early in the cycle without causing heat release during the compression stroke and this enables the heat release profile to be shaped.

scholarly journals The Effects of Biodiesel on NOx Emissions for Automotive Transport

2022 ◽  
Vol 24 (1) ◽  
pp. B59-B66
Author(s):  
Ruslana Kolodnytska ◽  
Oleksandr Kravchenko ◽  
Juraj Gerlici ◽  
Kateryna Kravchenko
Keyword(s):  
Carbon Dioxide ◽  
Nitrogen Oxides ◽  
Diesel Fuel ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Flame Temperature ◽  
Internal Combustion ◽  
Nox Formation ◽  
Automotive Engine ◽  
The Impact

Automobiles with internal combustion engine using diesel fuel have large harmful emissions of nitrogen oxides and soot, which affect the health of the population and especially children and carbon dioxide, which is dangerous for the planet as a whole. Biodiesel is used in Europe as an additive to diesel fuel to reduce soot emissions (including carcinogens), as well as to improve the balance of carbon dioxide on the planet. Using the biodiesel in internal combustion engines tends to show higher nitrogen oxides emissions compared to diesel. In this paper, the impact of flame temperature, ignition delay and density on NOx formation of biodiesel and its component for both stationary engine and automotive engine were analysed. Emissions of nitrogen oxides increase with increasing load. In no-load modes, biodiesel shows lower emissions of nitrogen oxides than diesel.

Performance, Combustion Characteristics and Emission Tests of Single Cylinder Engine Running on Fusel Oil - Diesel Blended (F20) Fuel

2017 ◽  
Vol 9 (3) ◽  
Author(s):  
O.I. Award ◽  
R. Mamata ◽  
M.M. Noor ◽  
T.K. Ibrahim ◽  
I.M. Yusri
Keyword(s):  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Cetane Number ◽  
Compression Ignition ◽  
Heating Value ◽  
Fusel Oil ◽  
Single Cylinder ◽  
Research Areas ◽  
Compression Ignition Engines ◽  
Cylinder Compression

Alcohols produced from a renewable source are amongst the important alternative fuels for internal combustion engines. Investigations on alternative fuels for compression ignition engines regarded as one of the major research areas. This paper details an experimental examination of the performance and emissions in single cylinder compression ignition engines operating with fusel oil F20 and pure diesel F0 at five engine speeds and 50% engine load. The test results indicated that the engine power and torque slightly decrease with the F20 at low speeds compared with pure diesel. Further, the in-cylinder pressure was decreased at all engine speed for F20 in comparison with pure diesel. The volumetric efficiency and fuel consumption were increased for F20 due the low heating value of fusel oil. The results showed that CO2 and CO emissions were increased because of the water content, low heating value and low cetane number for fusel oil. The maximum reduction in NOx emissions was 18% for F20 at 1500 rpm.

Low NOx and Low Smoke Operation of a Diesel Engine Using Gasoline-Like Fuels

2009 ◽  
Author(s):  
Gautam Kalghatgi ◽  
Leif Hildingsson ◽  
Bengt Johansson
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Compression Ratio ◽  
Diesel Fuel ◽  
Ignition Delay ◽  
Cetane Number ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Single Cylinder ◽  
Intake Pressure

Much of the technology in advanced diesel engines, such as high injection pressures, is aimed at overcoming the short ignition delay of conventional diesel fuels to promote premixed combustion in order to reduce NOx and smoke. Previous work in a 2 litre single cylinder diesel engine with a compression ratio of 14 has demonstrated that gasoline fuel, because of its high ignition delay, is very beneficial for premixed compression ignition compared to a conventional diesel fuel. We have now done similar studies in a smaller — 0.537 litre — single cylinder diesel engine with a compression ratio of 15.8. The engine was run on three fuels of very different auto-ignition quality — a typical European diesel fuel with a cetane number (CN) of 56, a typical European gasoline of 95 RON and 85 MON with an estimated CN of 16 and another gasoline of 84 RON and 78 MON (estimated CN of 21). The previous results with gasoline were obtained only at 1200 rpm — here we compare the fuels also at 2000 rpm and 3000 rpm. At 1200 rpm, at low loads (∼4 bar IMEP) when smoke is negligible, NOx levels below 0.4 g/kWh can be easily attained with gasoline without using EGR while this is not possible with the 56 CN European diesel. At these loads, the maximum pressure rise rate is also significantly lower for gasoline. At 2000 rpm, with 2 bar absolute intake pressure, NOx can be reduced below 0.4 g/kWh with negligible smoke (FSN <0.1) with gasoline between 10 and 12 bar IMEP using sufficient EGR while this is not possible with the diesel fuel. At 3000 rpm, with the intake pressure at 2.4 bar absolute, NOx of 0.4 g/KWh with negligible smoke was attainable with gasoline at 13 bar IMEP. Hydrocarbon and CO emissions are higher for gasoline and will require after-treatment. High peak heat release rates can be alleviated using multiple injections. Large amounts of gasoline, unlike diesel, can be injected very early in the cycle without causing heat release during the compression stroke and this enables the heat release profile to be shaped.

Low Temperature Gasoline Combustion With Diesel Micro-Pilot Injection in a Six-Cylinder Heavy Duty Engine

2012 ◽  
Author(s):  
Florian Bach ◽  
Clemens Hampe ◽  
Uwe Wagner ◽  
Ulrich Spicher ◽  
Christina Sauer
Keyword(s):  
Low Temperature ◽  
Diesel Fuel ◽  
Operating Conditions ◽  
Dual Fuel ◽  
Pilot Injection ◽  
Heavy Duty ◽  
Engine Operation ◽  
Equal Distribution ◽  
Single Cylinder ◽  
Soot Emissions

This paper describes the operation of a heavy duty six-cylinder engine in a dual fuel, Low Temperature Combustion (LTC) mode with very low engine-out NOx und soot emissions according to the US EPA Tier IV final emission limits in the corresponding C1 test cycle. This operation mode makes use of a short pilot injection of diesel fuel, which is injected directly into the cylinder, to ignite a highly diluted, premixed gasoline air mixture. Multicylinder engine operation could be demonstrated over the entire engine operating map with loads of up to 2 MPa BMEP. Expensive aftertreatment systems for NOx and soot emissions are not required. This paper also discusses the challenges involved with the implementation of this combustion system on a multicylinder engine. When transferring the dual fuel LTC from a single cylinder research engine to a multicylinder engine, the design of some engine components, e.g. the camshaft and the piston, were changed. The intake manifold is modified with port fuel injectors for ideal gasoline mixture preparation and equal distribution to all cylinders. To avoid cylinder imbalances, it is possible to control the injected masses of gasoline and diesel fuel for the pilot injection on a per-cylinder basis. Achieving high dilution for ignition delay via EGR and boosted intake pressure to avoid high pressure rise rates and knocking presents challenges for the two-stage turbocharger design. Additionally, high EGR rates and EGR cooling for increased loads are addressed. Finally, experiments to determine the significant control parameters for the combustion process are performed on the engine. In the course of these investigations, dual fuel LTC could be transferred from a single cylinder research engine to a multicylinder engine; previously obtained single-cylinder operating conditions could be achieved even at high loads.

scholarly journals Prospective types of alternative fuels for internal combustion engines

2019 ◽  
pp. 97-106
Author(s):  
S. F. Levko ◽  
B. V. Dolishnii ◽  
В. М. Melnyk
Keyword(s):  
Diesel Fuel ◽  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Cetane Number ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Exhaust Gases ◽  
Alcohol Industry ◽  
Fuel Mixtures ◽  
Fusel Oils

Currently, the disposal and recycling of the alcohol industry products creates a number of difficulties due to the lack of well-established recycling lines in Ukraine. Since 1998, eight enterprises of the state-owned concern Ukrspirt have been converted to produce high-octane oxygen-containing additives (CFCs) for ethanol-based fuels to organize the processing of waste from the alcohol industry. During this time, they produced 28.2 thousand tonnes of CALs, but CALA enterprises face great difficulties in selling their products, as they are new and expensive. The influence of fusel oil additives on commodity fuels on the main physical and technical indicators of the obtained alternative fuels is considered in the paper. According to the results of studies of octane number, we have established the optimal compositions of fuel mixtures of fusel oils with gasoline A-80 can contain up to 10% of the latter. For mixtures of fusel oils with diesel fuel by cetane number, their optimum content in diesel fuel is from 4 to 10% by volume. But, according to the trends of the development of diesel engines, the compression ratio increases, which allows the use of diesel fuel with higher cetane number, and therefore it is possible to raise the content of fusel oils in diesel fuel to 12%. According to the results of studies of the environmental performance of the ZIL-130 engine when fusel oils are added to commercial gasoline in an amount of 2 to 10% vol. the CO content in ICE exhaust gases decreases by 9.3%, fuel consumption increases by 6.5%, hydrocarbons by 10.2% and nitrogen oxide by 16.9%. As a result of increasing the content of fusel oils in diesel from 0 to 6%, there is an increase in mass flow rate of fuel to 6.1%, an increase in the concentration of hydrocarbons to 10% and nitrogen oxides by 1.9% in the exhaust gases of the engine D21A1. Thus, as we see today, along with traditional fuels for internal combustion engines, it is possible to use their alternative substitutes quite efficiently both in their pure form and in mixtures with them. There are all prerequisites for this in Ukraine and the region, the only question is the financing of these projects.

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