Development and Validation of a Multi-zone Predictive Combustion Model for Large-Bore Dual-Fuel Engines

Dual-fuel engines at part loads inevitably suffer from lower thermal efficiency and higher carbon monoxide and unburned fuel emission. The present work was carried out to investigate the combustion characteristics of a dual-fuel (diesel-gas) engine at part loads, using a single-zone combustion model with detailed chemical kinetics for combustion of natural gas fuel. The authors have developed software in which the pilot fuel is considered as a subsidiary zone and a heat source derived from two superimposedWiebe combustion functions to account for its contribution to ignition of the gaseous fuel and the rest of the total released energy. The chemical kinetics mechanism consists of 112 reactions with 34 species. This quasi-two-zone combustion model is able to establish the development of the combustion process with time and the associated important operating parameters, such as pressure, temperature, heat release rate (HRR), and species concentration. Therefore, this paper describes an attempt to investigate the combustion phenomenon at part loads and using hot exhaust gas recirculation (EGR) to improve the above-mentioned drawbacks and problems. By employing this technique, it is found that lower percentages of EGR and allowance for its thermal and radical effects have a positive influence on performance and emission parameters of dual-fuel engines at part loads. Predicted values show good agreement with corresponding experimental values under special engine operating conditions (quarter-load, 1400 r/min). Implications are discussed in detail.

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Combustion Quasi-Two Zone Predictive Model for Dual Fuel Engines

10.1115/imece1999-0853 ◽

1999 ◽

Author(s):

G. H. Abd Alla ◽

H. A. Soliman ◽

O. A. Badr ◽

M. F. Abd Rabbo

Keyword(s):

Predictive Model ◽

Combustion Process ◽

Chemical Species ◽

Kinetic Scheme ◽

Chemical Kinetic ◽

Operating Conditions ◽

Gaseous Fuel ◽

Combustion Model ◽

Dual Fuel ◽

Dual Fuel Engines

Abstract A quasi-two zone predictive model developed in the present work for the prediction of the combustion processes in dual fuel engines and some of their performance features. Methane is used as the main fuel while employing a small quantity of liquid fuel (pilot) injected through the conventional diesel fuel system. This model emphasizes the effects of chemical kinetics activity of the premixed gaseous fuel on the combustion performance, while the role of the pilot fuel in the ignition and heat release processes is considered. A detailed chemical kinetic scheme consists of 178 elementary reaction steps and 41 chemical species is employed to describe the oxidation of the gaseous fuel from the start of compression to the end of expansion process. The associated formation and concentrations of exhaust emissions are correspondingly established. This combustion model is able to establish the development of the combustion process with time and the associated important operating parameters such as pressure, temperature, rates of energy release and composition. Predicted values for methane operation show good agreement with corresponding previous experimental values over a range of operating conditions mainly associated with high load operation.

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Knock Prediction in Industrial Dual Fuel Engines Using a Two-Zone Combustion Model With Consideration of Chemical Kinetics

ASME 2008 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2008-1630 ◽

2008 ◽

Author(s):

Ahmed Al-Sened ◽

Hesameddin Safari ◽

Mojtaba Keshavarz ◽

Ghasem Javadirad

Keyword(s):

Diesel Fuel ◽

Fuel Injection ◽

Chemical Reactivity ◽

Gaseous Fuel ◽

Combustion Model ◽

Dual Fuel ◽

Injection Timing ◽

Boost Pressure ◽

Fuel Mass ◽

Dual Fuel Engines

Knock is well recognized as a destructive phenomenon to be avoided when running dual fuel engines. Typically, it occurs at high loads and high ambient temperatures and its onset has always been difficult to predict, particularly where multiple fuels are present. In a dual fuel engine, knock can occur from either the diesel or the gaseous fuel and it is recognised that the ratio of diesel fuel mass to gaseous fuel mass is an important index in determining which type of knock is predominant. This paper describes the development of a two-zone predictive model for the onset of knock in a dual fuel engine. Prediction of spark knock onset is the main objective of present work. A 9-step short mechanism with 11 chemical species, developed specifically for modelling dual fuel operation, is used to determine the chemical reactivity of the end-gas zone. The contribution of pilot diesel fuel combustion is taken into account by a heat release model. Chemical equilibrium is assumed for the burned gas zone. Simulation results predict the point of knock-limited BMEP and its dependency on operating parameters such as air intake temperature, boost pressure, start of pilot fuel injection timing and compression ratio. The results were first validated against some published engine analysis data and also some in-house performance prediction data. Secondly, a known dual-fuel development engine was simulated. Finally, the performance of an engine which had been converted from diesel to dual fuel during its service life was modeled but commercial constraints prevent the identification of this engine within this paper. However, good agreement with existing performance data was demonstrated in all these cases.

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Towards Marine Dual Fuel Engines Digital Twins—Integrated Modelling of Thermodynamic Processes and Control System Functions

Journal of Marine Science and Engineering ◽

10.3390/jmse8030200 ◽

2020 ◽

Vol 8 (3) ◽

pp. 200 ◽

Cited By ~ 2

Author(s):

Sokratis Stoumpos ◽

Gerasimos Theotokatos ◽

Christoforos Mavrelos ◽

Evangelos Boulougouris

Keyword(s):

Control System ◽

Combustion Process ◽

Integrated Modelling ◽

Mode Switching ◽

Combustion Model ◽

Dual Fuel ◽

Model Parameters ◽

Engine Operation ◽

Digital Twins ◽

Dual Fuel Engines

This study aims at developing an integrated model that combines detailed engine thermodynamic modelling and the control system functional modelling paving the way towards the development of high-fidelity digital twins. To sufficiently represent the combustion process, a multi-Wiebe function approach was employed, whereas a database for storing the combustion model parameters was developed. The developed model was employed for the systematic investigation of a marine four-stroke dual fuel engine response during demanding transient operation with mode switching and load changes. The derived results were analysed to identify the critical engine components and their effect on the engine operational limitations. The results demonstrate that the developed model can sufficiently represent the engine and its subsystems/components behaviour and effectively capture the engine control system’s functionality. The appropriate turbocharger matching along with the sufficient design of the exhaust gas waste gate valve and fuel control systems are crucial for ensuring the smooth engine operation of dual fuel engines.

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Characteristic Analysis in Combustion Process of Marine Dual Fuel Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.727-728.465 ◽

2015 ◽

Vol 727-728 ◽

pp. 465-468

Author(s):

Ping Qu ◽

Hong Liang Yu ◽

Feng Bo Zhang ◽

Wen Juan Zhao ◽

Feng Li ◽

...

Keyword(s):

Experimental Data ◽

Theoretical Basis ◽

Combustion Process ◽

Combustion Model ◽

Dual Fuel ◽

Characteristic Analysis ◽

Dual Fuel Engines

Currently, the research of marine dual fuel engine is rare, while the combustion process of marine dual fuel engine is no precise conclusion. This paper built a combustion model of dual fuel engine by AVL FIRE software, and compared experimental data to prove the accuracy of the model, analyzed the characteristics in combustion process of marine dual fuel engines, provided a theoretical basis for the further optimize and design of marine dual fuel engine.

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Development and Validation of a Quasi-Dimensional Dual Fuel (Diesel – Natural Gas) Combustion Model

SAE International Journal of Engines ◽

10.4271/2017-01-0517 ◽

2017 ◽

Vol 10 (2) ◽

pp. 483-500 ◽

Cited By ~ 12

Author(s):

Ivan Taritas ◽

Darko Kozarac ◽

Momir Sjeric ◽

Miguel Sierra Aznar ◽

David Vuilleumier ◽

...

Keyword(s):

Natural Gas ◽

Combustion Model ◽

Dual Fuel ◽

Gas Combustion ◽

Natural Gas Combustion ◽

Development And Validation

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CFD Study and Experimental Validation of a Dual Fuel Engine: Effect of Engine Speed

Energies ◽

10.3390/en14144307 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4307

Author(s):

Roberta De Robbio ◽

Maria Cristina Cameretti ◽

Ezio Mancaruso ◽

Raffaele Tuccillo ◽

Bianca Maria Vaglieco

Keyword(s):

Natural Gas ◽

High Performance ◽

Engine Speed ◽

Pollutant Emissions ◽

Dual Fuel ◽

Automotive Market ◽

Light Duty ◽

Viable Solution ◽

Dual Fuel Engines ◽

Gas Ratio

Dual fuel engines induce benefits in terms of pollutant emissions of PM and NOx together with carbon dioxide reduction and being powered by natural gas (mainly methane) characterized by a low C/H ratio. Therefore, using natural gas (NG) in diesel engines can be a viable solution to reevaluate this type of engine and to prevent its disappearance from the automotive market, as it is a well-established technology in both energy and transportation fields. It is characterized by high performance and reliability. Nevertheless, further improvements are needed in terms of the optimization of combustion development, a more efficient oxidation, and a more efficient exploitation of gaseous fuel energy. To this aim, in this work, a CFD numerical methodology is described to simulate the processes that characterize combustion in a light-duty diesel engine in dual fuel mode by analyzing the effects of the changes in engine speed on the interaction between fluid-dynamics and chemistry as well as when the diesel/natural gas ratio changes at constant injected diesel amount. With the aid of experimental data obtained at the engine test bench on an optically accessible research engine, models of a 3D code, i.e., KIVA-3V, were validated. The ability to view images of OH distribution inside the cylinder allowed us to better model the complex combustion phenomenon of two fuels with very different burning characteristics. The numerical results also defined the importance of this free radical that characterizes the areas with the greatest combustion activity.

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