Simulating the influence of injection timing, premixed ratio, and inlet temperature on natural gas/diesel dual-fuel HCCI combustion in a diesel engine

Energy security concerns and an abundant supply of natural gas in the USA provide the impetus for engine designers to consider alternative gaseous fuels in the existing engines. The dual-fuel natural-gas diesel engine concept is attractive because of the minimal design changes, the ability to preserve a high compression ratio of the baseline diesel, and the lack of range anxiety. However, the increased complexity of a dual-fuel engine poses challenges, including the knock limit at a high load, the combustion instability at a low load, and the transient response of an engine with directly injected diesel fuel and port fuel injection of compressed natural gas upstream of the intake manifold. Predictive simulations of the complete engine system are an invaluable tool for investigations of these conditions and development of dual-fuel control strategies. This paper presents the development of a phenomenological combustion model of a heavy-duty dual-fuel engine, aided by insights from experimental data. Heat release analysis is carried out first, using the cylinder pressure data acquired with both diesel-only and dual-fuel (diesel and natural gas) combustion over a wide operating range. A diesel injection timing correlation based on the injector solenoid valve pulse widths is developed, enabling the diesel fuel start of injection to be detected without extra sensors on the fuel injection cam. The experimental heat release trends are obtained with a hybrid triple-Wiebe function for both diesel-only operation and dual-fuel operation. The ignition delay period of dual-fuel operation is examined and estimated with a predictive correlation using the concept of a pseudo-diesel equivalence ratio. A four-stage combustion mechanism is discussed, and it is shown that a triple-Wiebe function has the ability to represent all stages of dual-fuel combustion. This creates a critical building block for modeling a heavy-duty dual-fuel turbocharged engine system.

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Dual-Fueling of a Prechamber Diesel Engine With Natural Gas

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3239836 ◽

1985 ◽

Vol 107 (4) ◽

pp. 914-921 ◽

Cited By ~ 4

Author(s):

S. Song ◽

P. G. Hill

Keyword(s):

Energy Consumption ◽

Diesel Engine ◽

Natural Gas ◽

Consumption Rate ◽

Dual Fuel ◽

Combustion Mechanism ◽

Injection Timing ◽

Cylinder Pressure ◽

Energy Consumption Rate ◽

Diesel Operation

The feasibility of dual-fuel operation with natural gas in a prechamber diesel engine was studied with special emphasis on fuel consumption and cylinder pressure development. The effects of air restriction, pilot diesel flow rate, and injection timing were also investigated. Near full load the fuel energy consumption rate was close to that of straight diesel operation though at part load (in the absence of air restriction) the fuel energy consumption rate was relatively high. In the absence of injection timing adjustment the maximum power output of dual-fuel operation was severely limited by the maximum cylinder pressure. Retarding the injection timing is effective in reducing the maximum cylinder pressure to a safe level. The analysis of apparent energy release indicates the differences in combustion mechanism between auto-ignition of diesel fuel in straight diesel operation and propagation of flame fronts in dual-fuel operation.

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Investigation of Effect on Environmental Performance of Using LNG as Fuel for Engines in Seaport Tugboats

Journal of Marine Science and Engineering ◽

10.3390/jmse9020123 ◽

2021 ◽

Vol 9 (2) ◽

pp. 123

Author(s):

Sergejus Lebedevas ◽

Lukas Norkevičius ◽

Peilin Zhou

Keyword(s):

Diesel Engine ◽

Natural Gas ◽

Baltic Sea ◽

Impact Assessment ◽

Fuel Consumption ◽

Dual Fuel ◽

Nox Emissions ◽

The Baltic Sea ◽

Emission Analysis ◽

The Baltic

Decarbonization of ship power plants and reduction of harmful emissions has become a priority in the technological development of maritime transport, including ships operating in seaports. Engines fueled by diesel without using secondary emission reduction technologies cannot meet MARPOL 73/78 Tier III regulations. The MEPC.203 (62) EEDI directive of the IMO also stipulates a standard for CO2 emissions. This study presents the results of research on ecological parameters when a CAT 3516C diesel engine is replaced by a dual-fuel (diesel-liquefied natural gas) powered Wartsila 9L20DF engine on an existing seaport tugboat. CO2, SO2 and NOx emission reductions were estimated using data from the actual engine load cycle, the fuel consumption of the KLASCO-3 tugboat, and engine-prototype experimental data. Emission analysis was performed to verify the efficiency of the dual-fuel engine in reducing CO2, SO2 and NOx emissions of seaport tugboats. The study found that replacing a diesel engine with a dual-fuel-powered engine led to a reduction in annual emissions of 10% for CO2, 91% for SO2, and 65% for NOx. Based on today’s fuel price market data an economic impact assessment was conducted based on the estimated annual fuel consumption of the existing KLASCO-3 seaport tugboat when a diesel-powered engine is replaced by a dual-fuel (diesel-natural gas)-powered engine. The study showed that a 33% fuel costs savings can be achieved each year. Based on the approved methodology, an ecological impact assessment was conducted for the entire fleet of tugboats operating in the Baltic Sea ports if the fuel type was changed from diesel to natural gas. The results of the assessment showed that replacing diesel fuel with natural gas achieved 78% environmental impact in terms of NOx emissions according to MARPOL 73/78 Tier III regulations. The research concludes that new-generation engines on the market powered by environmentally friendly fuels such as LNG can modernise a large number of existing seaport tugboats, significantly reducing their emissions in ECA regions such as the Baltic Sea.

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A Numerical Study on the Combustion Process and Emission Characteristics of a Natural Gas-Diesel Dual-Fuel Marine Engine at Full Load

Energies ◽

10.3390/en14051342 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1342

Author(s):

Van Chien Pham ◽

Jae-Hyuk Choi ◽

Beom-Seok Rho ◽

Jun-Soo Kim ◽

Kyunam Park ◽

...

Keyword(s):

Natural Gas ◽

Combustion Process ◽

Simulation Software ◽

Dual Fuel ◽

Injection Timing ◽

Emission Characteristics ◽

Cylinder Pressure ◽

Marine Engine ◽

Full Load ◽

Simulation Results

This paper presents research on the combustion and emission characteristics of a four-stroke Natural gas–Diesel dual-fuel marine engine at full load. The AVL FIRE R2018a (AVL List GmbH, Graz, Austria) simulation software was used to conduct three-dimensional simulations of the combustion process and emission formations inside the engine cylinder in both diesel and dual-fuel mode to analyze the in-cylinder pressure, temperature, and emission characteristics. The simulation results were then compared and showed a good agreement with the measured values reported in the engine’s shop test technical data. The simulation results showed reductions in the in-cylinder pressure and temperature peaks by 1.7% and 6.75%, while NO, soot, CO, and CO2 emissions were reduced up to 96%, 96%, 86%, and 15.9%, respectively, in the dual-fuel mode in comparison with the diesel mode. The results also show better and more uniform combustion at the late stage of the combustions inside the cylinder when operating the engine in the dual-fuel mode. Analyzing the emission characteristics and the engine performance when the injection timing varies shows that, operating the engine in the dual-fuel mode with an injection timing of 12 crank angle degrees before the top dead center is the best solution to reduce emissions while keeping the optimal engine power.

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Effect of pilot injection timing using crude palm oil biodiesel on combustion process on dual fuel engines with compressed natural gas as the main fuel

International Journal of Sustainable Engineering ◽

10.1080/19397038.2021.1943044 ◽

2021 ◽

pp. 1-17

Author(s):

Bambang Sudarmanta ◽

Dori Yuvenda ◽

Ary Bachtiar K.P. ◽

Arif Wahjudi ◽

Ahmad Arbi Trihatmojo

Keyword(s):

Natural Gas ◽

Palm Oil ◽

Combustion Process ◽

Dual Fuel ◽

Injection Timing ◽

Pilot Injection ◽

Crude Palm Oil ◽

Compressed Natural Gas ◽

Dual Fuel Engines ◽

Palm Oil Biodiesel

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Simulation Research on Combustion Process in a Natural Gas-Diesel Dual-Fuel Marine Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.525.227 ◽

2014 ◽

Vol 525 ◽

pp. 227-231 ◽

Cited By ~ 2

Author(s):

Min Xiao ◽

Chun Long Feng

Keyword(s):

Natural Gas ◽

Total Energy ◽

Combustion Process ◽

Power Reduction ◽

Dual Fuel ◽

Injection Timing ◽

Simulation Research ◽

Injection Duration ◽

Medium Speed ◽

The Right

In order to solve the problem of Diesel natural gas dual fuel engine, such as power reduction, low charging efficiency, the conception of diesel engine fueled with pilot-ignited directly-injected liquefied natural gas is put forward. On the basis of this theory, a medium speed diesel of the marine is refitted into dual fuel engine, in order to keep original power, decrease the temperature of combustion and reduce emission. The LNG injection timing, duration of LNG injection and the different ratios the pilot diesel to total energy are studied the method of AVL FIRE software. Conclusions are as follows: When the different ratios pilot diesel to total energy is 0.5%, the engine can not work; Delaying the LNG injection timing, shortening the LNG injection duration and choose the right ratios pilot diesel to total energy can reach the indicated power of original machine, and the NOx emissions level will be greatly reduced.

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Experimental investigation concerning the effect of natural gas percentage on performance and emissions of a DI dual fuel diesel engine

Applied Thermal Engineering ◽

10.1016/s1359-4311(02)00187-4 ◽

2003 ◽

Vol 23 (3) ◽

pp. 353-365 ◽

Cited By ~ 180

Author(s):

R.G Papagiannakis ◽

D.T Hountalas

Keyword(s):

Experimental Investigation ◽

Diesel Engine ◽

Natural Gas ◽

Dual Fuel ◽

Performance And Emissions

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Performance of Dual Fuel Engine Running on Jojoba Oil as Pilot Fuel and CNG or LPG

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 3 ◽

10.1115/ht2007-32016 ◽

2007 ◽

Cited By ~ 2

Author(s):

Mohamed Y. E. Selim ◽

M. S. Radwan ◽

H. E. Saleh

Keyword(s):

Methyl Ester ◽

Natural Gas ◽

Pressure Rise ◽

Combustion Noise ◽

Dual Fuel ◽

Maximum Pressure ◽

Injection Timing ◽

Pressure Rise Rate ◽

Rise Rate ◽

Pilot Fuel

The use of Jojoba Methyl Ester as a pilot fuel was investigated for almost the first time as a way to improve the performance of dual fuel engine running on natural gas or LPG at part load. The dual fuel engine used was Ricardo E6 variable compression diesel engine and it used either compressed natural gas (CNG) or liquefied petroleum gas (LPG) as the main fuel and Jojoba Methyl Ester as a pilot fuel. Diesel fuel was used as a reference fuel for the dual fuel engine results. During the experimental tests, the following have been measured: engine efficiency in terms of specific fuel consumption, brake power output, combustion noise in terms of maximum pressure rise rate and maximum pressure, exhaust emissions in terms of carbon monoxide and hydrocarbons, knocking limits in terms of maximum torque at onset of knocking, and cyclic data of 100 engine cycle in terms of maximum pressure and its pressure rise rate. The tests examined the following engine parameters: gaseous fuel type, engine speed and load, pilot fuel injection timing, pilot fuel mass and compression ratio. Results showed that using the Jojoba fuel with its improved properties has improved the dual fuel engine performance, reduced the combustion noise, extended knocking limits and reduced the cyclic variability of the combustion.

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