The use of natural gas (NG) in dual-fuel heavy-duty engines has the potential to reduce pollutant and greenhouse gas (GHG) emissions from the transport sector when compared to the conventional diesel engines. However, NG composition and methane slip…
The conversion of existing diesel engines to spark ignition (SI) operation by adding a low-pressure injector in the intake manifold for fuel delivery and replacing the original high-pressure fuel injector with a spark plug to initiate and control the…
The projected increase in the availability of gaseous fuels by growing popularity of household natural gas (NG) filling stations and the increase in the production of gaseous biogas-derived fuels is conducive to an increase in the use of NG fuel.…
There is a need for decarbonization in power generation and transportation. Natural gas can replace conventional petroleum fuels due to its low carbon-to-hydrogen ratio, especially in existing diesel engines. This paper was based on the hypothesis…
Dual-fuel (DF) combustion using natural gas and diesel has received considerable attention in the on- and off-road freight transportation sectors owing to its potential use in achieving better fuel economy and cleaner combustion. To determine the…
A sub-scale and an engineering-scale burner were designed, built, and tested in an effort to develop a single-nozzle burner capable of efficiently atomizing and burning neat, emulsified, and weathered crude oil for spill response and remediation. The…
The combustion of natural gas reduces fuel cost and generates less emissions of carbon dioxide and particulate matter (PM) than diesel and gasoline. Replacing diesel by natural gas in internal combustion engines is of great interest for…
Adding hydrogen to natural gas is a promising way to improve the ignition stability and reduce the greenhouse gas emissions of pilot-ignition direct-injection natural gas engines. Most of the previous studies concerning hydrogen-enriched natural gas…
The characteristics of the ionization current, pressure, and flame schlieren photos during the combustion process of natural gas-hydrogen/CO2 blends were studied using high-speed schlieren data acquisition technology and flame ionization analysis…
Energy fraction of the main (premixed) fuel and pilot injection timing are important in dual-fuel pilot diesel ignition engine. In the present study, natural gas, which is the main premixed fuel, is induced into the engine through the intake port,…
Homogeneous charge compression ignition (HCCI) combustion phasing control is one of the most difficult challenges of operating this new concept of combustion. In this study, a dimethyl ether (DME)/natural gas (NG) blend fuel HCCI engine is simulated…
Natural gas (NG) is attractive for heavy-duty (HD) engines for reasons of cost stability, emissions, and fuel security. NG cannot be reliably compression-ignited, but conventional gasoline ignition systems are not optimized for NG and are challenged…
The aim of this study is to apply the artificial neural network to identify the mathematical model of the combustion of a reactivity-controlled compression ignition (RCCI) engine fueled with natural gas and diesel oil. In this study, a…
Homogeneous Charge Compression Ignition (HCCI) is a promising advanced combustion concept with high thermal efficiency and low exhaust emissions. This work purposes a computationally-efficient, zero-dimensional (0-D) HCCI combustion model that does…
Experimental and numerical studies on the effect of spark ignition engine fueled with different fractions of CNGCO2H2 blend were conducted. The results show that with the increase of CO2 fraction, the effect of vortex on the flame wrinkle is…
A solution to increase the use of natural gas in U.S. is to convert existing diesel engines to natural-gas spark-ignition operation through the addition of a gas injector in the intake manifold and of a spark plug in place of the diesel injector.…
Engines fuelled with Liquefied natural gas (LNG) have been widely used in the heavy-duty vehicles. However, they suffer from poor combustion performance and flame instability under fuel-lean condition. In this work, experiments were performed on a…
Lean-burn natural-gas spark-ignition combustion inside a diesel geometry is characterized by two distinct and successive events: a rapid burning process inside the piston bowl, followed by a much slower burn inside the squish region. This paper used…
The conversion of existing diesel engines to natural-gas spark-ignition operation would reduce the dependence on oil imports, reduce the burden on refining capacity, and increase U.S. energy security. The use of simple combustion models such as the…
This research presents the test results carried out in a diesel engine converted to spark ignition (SI) using gaseous fuels, applying a geometry change of the pistons combustion chamber (GCPCC) to increase the turbulence intensity during the…
Dual-fuel premixed charge compression ignition (DF-PCCI) combustion has been proven to be a viable alternative to conventional diesel combustion in heavy-duty compression ignition engines due to its low nitrogen oxides (NOx) and particulate matter…
The aim of this study is to implement the multi-inputmulti-output optimization of reactivity-controlled compression-ignition combustion in a heavy-duty diesel engine running on natural gas and diesel fuel. A single-cylinder heavy-duty diesel engine…
The dual fuel combustion mode, the use of bi-fueled natural gas and diesel fuel, is an attractive alternative to standard spark ignition or compression ignition combustion modes due to potential benefits of lower CO2 emissions, lower fuel costs and…
The paper evaluates different strategies of dual fuel (DF) operation in search of a solution that enables DF at low load. The strategies that were explored are conventional DF with increased intake temperature, split injection, and reactivity…
In CNG/Diesel reactivity controlled compression ignition (RCCI) engines, because of low reactivity fuel (natural gas) spread of flame in combustion chamber suffers process of combustion and also there is more unburned hydrocarbon emission in this…
The coordinated control of combustion boundary conditions and fuel chemistry is the core academic idea of homogenous charge compression ignition (HCCI) combustion. Realizing controlled combustion is the current development goal of HCCI engine and…
High-pressure direct-injection (HPDI) natural gas engines continue to draw much attention for the highly efficient and clean combustion process compared to traditional diesel engines. However, the real ignition processes of HPDI natural gas engines…
In this work, a comprehensive evaluation was conducted to study the effect of diesel injection strategy on natural gas-diesel dual-fuel combustion using micro genetic algorithm (micro-GA) optimization. Firstly, the effects of different injection…
The effects of hydrogen enrichment in a naturally aspirated spark ignition engine fuelled with compressed natural gas were investigated. A mixer that can control the enrichment fraction and assure homogeneity of hydrogen in CNG was used in the…
In order to reduce the emissions of polluting gases and contribute to the efficient use of energy, natural gas has gained relevance due to its cleaner burning when compared to gasoline and diesel oil. In this work, a zero-dimensional thermodynamic…
In this research, it was investigated the energy fraction and emission characteristics of natural gas/diesel dual-fuel combustion in terms of the combustion index such as combustion duration and mass fraction burned 50% (MFB50) of a 6-L heavy-duty…
Environmental benefits are one of the main motivations encouraging the use of natural gas as fuel for internal combustion engines. In addition to the better impact on pollution, natural gas is available in many areas. In this context, the present…
A singlecylinder marine diesel engine was modified to be operated in reactivity controlled compression ignition (RCCI) combustion mode. The engine fueling system was upgraded to a common rail fuel injection system. Natural gas (NG) was used as port…
Compressed natural gas/Diesel dual-fuel combustion mode, the partial replacement of diesel fuel with cleaner fuel, is one of the most important strategies to achieve clean efficient combustion. Thus, the current work investigated the effect of…
On- and off-road heavy-duty diesel engines modified to spark-ignition natural gas operation can reduce U.S. dependence on imported oil and enhance national energy security. Engine conversion can be achieved through the addition of a gas injector in…
Compressed natural gas (CNG) is a promising alternative fuel for compression ignition (CI) engines under dual-fuel (DF) mode operation. Its application on commercial heavy-duty multicylinder diesel engines is scarcely reported, and its potential…
A genetic algorithm(GA)numerical optimization platform was developed by coupling a micro GA code with a computational fluid dynamics(CFD)code. Based on this optimization platform, natural gas and diesel dualfuels combustion was systematically…
In this research, a reduced chemical kinetic mechanism was coupled in computational fluid dynamics (CFD) model to study the detailed influence mechanism of natural gas (NG) energy fraction on the diesel pilot ignition (DPI) NG engines. Based on the…
In this paper, the ignition delay and laminar combustion characteristics of natural gas were tested in a chemical shock tube and a constant volume combustion reactor, respectively, and simulated with the Gri_3.0, USC_2.0 and NUI_Galway models,…
New ignition delay time (IDT) data for stoichiometric natural gas (NG) blends composed of C1-C5 n-alkanes with methane as the major component were recorded using a high pressure shock tube (HPST) at reflected shock pressures (p5) and temperatures…
The addition of a spark plug in place of the original fuel injector and fumigating natural gas (NG) inside the intake manifold is an economical way to convert heavy-duty diesel engines to NG spark-ignition (SI) operation. The literature shows that,…
Increasingly restrictive limits on Oxides of Nitrogen - NOx levels and desire for low methane emissions from gas engines are driving the change from lean-burn to stoichiometric combustion strategies on heavy-duty on-highway natural gas engines in…
Numerical simulation of flow, mixture formation and combustion in a direct injection natural gas engine was conducted using the large-eddy simulation method. The dynamic thickened flame model coupling with a skeletal methane reaction mechanism was…
In order to investigate the effects of hydrogen enrichment on the combustion and emission formation processes of large medium-speed natural gas engines ignited by pre-chamber turbulent jets, a computational fluid dynamic method coupled chemical…
The effects of intake pressures and EGR rates on the natural gas/diesel dual-fuel combustion under a high load condition (brake power of 100 kW) were evaluated using a 6-L CI engine in this study. Natural gas fraction was fixed as 80% of total input…
Converting existing compression ignition (CI) engines to spark ignition (SI) operation can increase the use of natural gas (NG) in heavy-duty engine applications and reduce the reliance on petroleum fuels. Gas fumigation upstream of the intake…
To evaluate the effect of exhaust gas recirculation (EGR) and variable fuel reactivity on knock and misfire in spark ignited national gas engines, experiments were conducted in a rapid compression machine to measure homogeneous ignition delay, flame…
The Turbulent Jet Ignition is an effective concept to achieve stable lean burning for natural gas engines due to the multiple ignition sources, high ignition energy, and fast combustion rate. A variation of the ignition location has a non-negligible…
In this study, the performance of a single-stage gas gun with a natural gas-air mixture as the propellant gas is investigated by measuring the explosion pressure and the projectile velocity. In this work, the combined effect of elevated initial…