Browse Topic: Natural gas

Items (2,282)
Ozone (O3) was introduced into the intake air in a natural gas fueled engine ignited by micro-pilot of diesel fuel, to utilize the reactive O-radicals decomposed from the O3 for the promotion of the combustion and for improvements in the thermal efficiency and exhaust emissions. Experiments were carried out in a single cylinder engine to elucidate the effects of the ozone addition under the lean burn conditions. A supercharger was employed to increase the intake air amount and vary the equivalence ratio of natural gas. The experimental results showed that the O3 addition has a limited effect on the ignition of the diesel fuel injected near top dead center, while the heat release during the flame propagation in the natural gas/air mixture was increased at the lower equivalence ratio of natural gas. Further the ignition of natural gas was promoted, resulting in the increase of the combustion efficiency and the degree of constant volume heat release. The cooling loss and the NOx emissions
Kobashi, YoshimitsuMiyata, ShokiKawahara, NobuyukiInagaki, Ryuya
In the ongoing effort to decarbonize energy supply, a notable shift involves the conversion or retrofitting of combined heat and power plants to operate on hydrogen as an alternative to natural gas. In this transformative landscape, extensive research is underway to develop and explore innovative combustion processes for hydrogen-fueled engines, aiming to comprehend and optimize combustion processes concerning both engine performance and emissions. Among the various methods available for monitoring the combustion process and engine control, ion current sensing presents itself as a viable option. A unique feature of this research lies in utilizing the engine's spark plug itself as an electrical sensor, measuring the ion current generated during the flame development and combustion processes. Given the limited research on ion current sensing for hydrogen combustion processes, a series of experiments were conducted and presented in this work. These experiments involved sweeps of water-to
Salim, NaqibBeltaifa, YoussefKettner, MauriceLoose, OliverWeißgerber, Tycho
To study the real driving emission characteristics of light-duty vehicles fueled with liquefied petroleum gas (LPG) and gasoline in a high-altitude city, experimental investigations were performed on two LPG taxis and three gasoline passenger cars in Lhasa using a portable emission measurement system (PEMS). The results reveal that the emission factors of CO2, CO, NOx, and HC of LPG taxis are 159.19±11.81, 18.38±9.73, 1.53±0.46, and 1.27±0.99 g/km, and those of gasoline cars are 223.51±23.1, 1.51±0.68, 0.27±0.16, and 0.06±0.04 g/km, respectively. The emissions show strong relationships with driving mode, which is considerably affected by driving behavior. Furthermore, as vehicle speed increases, the emission factors of both LPG taxis and gasoline cars decrease. The emission rates of both types of vehicles are low and change slightly at a vehicle specific power (VSP) of 0 kW/t or below; After that, the rates slowly increase initially and then increase rapidly with increasing VSP. These
Lyu, MengXu, YanHuang, MeihongWang, Yunjing
The Tour engine is a novel split-cycle internal combustion engine (ICE) that divides the four-stroke Otto cycle of a conventional ICE between two separate cylinders, an intake and compression cylinder and a second expansion and exhaust cylinder, interconnected by an innovative charge transfer mechanism. The engine working fluid, air and fuel, is inducted into the engine and compressed by a dedicated compression cylinder, transferred with minimal pressure loss via an input port to a specifically designed combined spool shuttle transfer mechanism and combustion chamber. It is then ignited and then transferred from the combustion chamber via an exit port to a separate expansion cylinder where it is expanded and exhausted from the engine. The primary advantage of the Tour engine is that it provides the engineering freedom to independently design, control and optimize the compression, combustion, and expansion processes within a slider-crank piston engine. By decoupling the compression
Tour, OdedCho, KukwonHofman, YehoramAnderson, BradleyKemmet, RyanMorris, DanielWahl, MichaelBhanage, PratikSivan, EhudTour, GiladAtkinson, ChrisTour, Hugo
In cogeneration system, the pre-chamber natural gas engine adopts combustion technologies such as ultra-high supercharged lean burn and Miller cycle to increase the theoretical efficiency by increasing the specific heat ratio and the mechanical efficiency by improving the specific power. In recent years, the use of hydrogen fuel has been attracting attention in order to achieve carbon neutrality, and it is required to operate existing high-efficiency natural gas engines by appropriately mixing hydrogen. For this purpose, it is important to have natural gas and hydrogen co-combustion technology that allows combustion at any mixture ratio without major modifications. The authors mixed hydrogen into the fuel of an ultra-high supercharged lean burn pre-chamber natural gas engine (Bore size: 200mm) that has already achieved high efficiency and performed combustion experiments at BMEP (Brake mean effective pressure) of 2 MPa or more. The engine load and hydrogen mixture ratio were used as
Morikawa, KojiKimura, ShinSakai, ShunyaMoriyoshi, Yasuo
Since the obvious difficulties in realizing a lightweight long-range full electric powertrain, Internal Combustion Engines (ICEs) are still the most suitable solution for heavy-duty mobility. In a fossil fuel free scenario, bioethanol is one of the most interesting alternative fuels. Its high-octane number, high latent heat of vaporization and high laminar flame speed guarantee high performance with reduced pollutant emissions compared to other Spark Ignition (SI) engine fuels. However, ethanol evaporation and corrosivity represent quite serious challenges. This work aims at investigating the actual performance of a heavy-duty turbocharged SI ICE fueled with ethanol at full load and different engine speeds. A 1-D numerical model that includes fuel evaporation sub-models was developed in order to evaluate the engine performance, ensuring ethanol evaporation in each operating condition. The 1-D numerical model was validated through an experimental campaign carried out with the above
Falbo, BiagioPerrone, DiegoCastiglione, Teresa
Decarbonizing regional and long-haul freight is challenging due to the limitations of battery-electric commercial vehicles and infrastructure constraints. Hydrogen fuel cell medium- and heavy-duty vehicles (MHDVs) offer a viable alternative, aligning with the decarbonization goals of the Department of Energy and commercial entities. Historically, alternative fuels like compressed natural gas and liquefied propane gas have faced slow adoption due to barriers like infrastructure availability. To avoid similar issues, effective planning and deploying zero-emission hydrogen fueling infrastructure is crucial. This research develops deployment plans for affordable, accessible, and sustainable hydrogen refueling stations, supporting stakeholders in the decarbonized commercial vehicle freight system. It aims to benefit underserved and rural energy-stressed communities by improving air quality, reducing noise pollution, and enhancing energy resiliency. This research also provides a blueprint
Sujan, VivekSun, RuixiaoJatana, GurneeshFan, Junchuan
Combining a low-carbon content fuel, such as natural gas, with a high-efficiency engine can reduce greenhouse gas emissions significantly in hard-to-electrify long-haul trucking applications. Turbo-compounding, where an additional power turbine is installed in the exhaust stream after the turbocharger turbine, can extract useful amounts of energy from diesel engine exhaust at high loads. This work assesses the net benefits of combining turbo-compounding with a high-efficiency, natural gas fuelled heavy-duty engine. The effects on brake specific fuel consumption (BSFC), greenhouse gas emissions, and engine-out emissions of nitrogen oxides (NOx) and methane (CH4) are considered. The experimentally validated 1D model for a 13L diesel pilot- direct injection of natural gas, heavy-duty engine in GT-SUITETM is used to develop a series turbo-compound model. The effects of turbine sizes and flow capacities in fixed-geometry turbocharging and power turbines are evaluated on the engine’s
Balazadeh, NavidMunshi, SandeepShahbakhti, MahdiMcTaggart-Cowan, Gordon
The rapid advancement of alternative energy and energy-saving technologies in China underscores the importance of conducting a comprehensive analysis of the total cost of ownership (TCO) for commercial vehicles such as buses and trucks. To address the challenges of quantifying time-sensitive and implicit costs, this study has developed an extensive database and a web-based modeling tool to evaluate the TCO of these vehicles for the period 2020–2040. The tool allows for user-customized inputs and generates TCO estimates across multiple technology evolution scenarios, encompassing nearly 200 vehicle types categorized by class, intended use, and powertrain technology, within diverse technology development pathways. The model integrates critical cost factors, including vehicle purchase costs, financing costs, energy expenditures, and inconvenience costs, providing a detailed assessment of long-term ownership costs. Key findings indicate that under the reference scenario, battery electric
Tan, XiaoluOu, Shiqi(Shawn)Wu, ShuhongChen, YongjianLin, Zhenhong
There is a need to reduce both the greenhouse gas emissions of internal combustion engines, and the reliance on traditional fossil fuels like Ultra Low Sulfur Diesel (ULSD). In this research, a synthetic paraffinic kerosene fuel, designated S8 and created from natural gas feedstocks using the Fischer-Tropsch process was investigated to determine its autoignition and combustion characteristics, emissions, and tribological properties. This fuel, S8, was found to have a Derived Cetane Number (DCN) of 62, which reflects a shorter Ignition Delay (ID), and Combustion Delay (CD) compared to ULSD, which has a DCN of 48. However, due to the chemical properties of S8, it lacks sufficient lubrication qualities in comparison to ULSD, so addition of 3% methyl oleate by mass was used to improve lubricity. The shorter ignition delay of S8, initially observed in a Constant Volume Combustion Chamber (CVCC) and confirmed in a fired Common Rail Direct Injection (CRDI) experimental engine. Investigations
Soloiu, ValentinWillis, JamesNorton, ColemanDavis, ZacharyGraham, TristanNobis, Austin
In order to reduce the environmental impact of transportation, the adoption of low and zero carbon fuel is needed to reduce the greenhouse gas emissions from engines, both from tailpipe and well-to-wheel perspectives. However, for some of the promising fuels, such as renewable natural gas and ammonia, the relatively low chemical reactivity and laminar flame speed bring challenge to a rapid and efficient combustion process, especially under lean or diluted conditions to suppress NOx emissions, leading to reduced combustion and thermal efficiencies. To tackle the challenge, high in-cylinder flow speed is needed to shorten the combustion duration, together with strong ignition sources to support the initial flame kernel development. In this paper, an ignition energy modulation system is developed to enhance both discharge current and discharge energy of a spark event to secure the ignition process. Moreover, a rapid compression machine is employed to compress the fuel-air mixture to the
Jin, LongYu, XiaoZhou, QingReader, GrahamLi, LiguangZheng, Ming
To reduce carbon dioxide emissions from automobiles, the introduction of electric vehicles to the market is important; however, it is challenging to replace all existing IC engine vehicles with electric ones. Consequently, there is increasing anticipation for the use of carbon-neutral fuels, such as e-fuels. This study investigates the effects of GTL (gas-to-liquid), as a substitute for e-fuel, produced from natural gas via the Fischer–Tropsch synthesis method and polyoxymethylene dimethyl ether (OMEmix) produced from methanol, on engine performance. Additionally, combustion image analysis was conducted using a rapid compression and expansion machine (RCEM). GTL fuel combusts similarly to conventional diesel fuel but has slightly lower smoke emissions because it does not contain aromatic hydrocarbons. Further, its high cetane number results in better ignition properties. During the combustion, unburnt hydrocarbons and smoke are generated in the spray flame interference region near the
Shibata, GenYuan, HaoyuYamamoto, HiroyaTanaka, ShusukeOgawa, Hideyuki
Closed-loop combustion control is highly beneficial for improving the efficiency and reducing the emissions of spark ignition internal combustion engines. In this paper, the key parameter (CA50) of closed-loop combustion control and its effect on the combustion and emissions were explored experimentally in a six-cylinder hydrogen enriched compressed natural gas (HCNG) engine. Moreover, the particle swarm optimization (PSO) back propagation neural network (BPNN) algorithm improved by various hybrid strategies was employed for CA50 prediction. The experimental results reveal that CA50 has a significant impact on the combustion characteristics and emissions of the HCNG engine. Meanwhile, statistical analysis illustrates that CA50 follows a normal distribution and has no self-correlation. Considering the one-to-one correspondence between CA50 and the spark timing, it is suitable to select CA50 as the feedback parameter. The simulation results indicate that the CA50 prediction model
Duan, HaoYan, YuRen, XianfengYin, XiaojunWang, JinhuaZeng, Ke
A significant amount of chemical fuel energy in internal combustion engines is wasted through exhaust heat. Waste heat recovery (WHR) systems can transform the heat into electrical energy using thermoelectric generators (TEG). This work utilizes a 1D CFD model to demonstrate the potential of TEG-WHR in improving the thermal efficiency of mass-production, compressed natural gas (CNG) engines used in commercial 22-ton heavy-duty trucks. First, the TEG with heat exchanger experiments are performed to measure thermal and electrical performance data under different fin pitches and inlet gas conditions (Re number, temperature, gas flow rate). These data are used to develop and validate a TEG model, which considers user-defined functions of heat transfer and flow friction coefficients to reproduce measured thermal/electrical characteristics of the integrated TEG with its heat exchanger. The engine experiments are conducted based on the speed–torque map (51 test conditions) of the JE05 heavy
Sok, RatnakKusaka, Jin
The increasing impacts of the greenhouse effect have driven the need to reduce pollutant emissions from internal combustion engines. Renewable fuels are promising alternatives for emission reduction, and enhancing engine efficiency can further decrease specific emissions. This study explores the development of dual-fuel engines to meet these goals, focusing on dual-fuel combustion in spark-ignition (SI) engines using two different bioethanol and natural gas mixtures. A novel methodology for 1-D predictive combustion simulation in dual-fuel SI engines was developed and implemented in GT-Suite software. The approach involves a straightforward estimation of the laminar flame speed of the fuel mixture and the calibration of turbulent combustion parameters using a genetic optimization algorithm, without the need for complex chemical kinetics models. The results indicate that the proposed methodology can reproduce combustion characteristics, achieving satisfactory outcomes across most tested
Pasa, Giovanni DuarteMartins, ClarissaCota, FilipeDornelles, HenriqueDuarte, ThalesRosalen, RodrigoPujatti, Fabrício José Pacheco
In the global scenario marked by the increasing environmental awareness and the necessity on reducing pollutant emission to achieve the decarbonization goals, action plans are being proposed by policy makers to reduce the impact of the climate change, mainly affecting the sectors that most contribute to CO2 emissions such as transportation and power generation. In this sense, by virtue of the National Energy Plan 2050, the Brazilian market will undergo the decommissioning of thermal power plants fueled by diesel and heavy fuel oil (HFO) by 2030, compromising about 6.7 GW of power capacity according to the Brazilian Electricity Regulatory Agency (ANEEL) database. An alternative to the scrapping of these engine power plants is their conversion to operate with fuels with a lower carbon footprint, such as the natural gas. This work, therefore, aims to numerically assess the conversion feasibility of a HFO large bore four-stroke turbocharged engine to operate with natural gas by means of a
Gonçalves, Vinícius FernandezZabeu, Clayton BarcelosAntolini, JácsonSalvador, RobertoAlmeida, RogérioValiati, Allan SoaresFilho, Guenther Carlos Krieger
As we move towards sustainable transportation, it is essential to look for alternative powertrain technologies that might reduce emissions and depend less on fossil fuels. This paper offers a thorough analysis and comparison of several viable solutions along with their benefits, cost and conclusion for hydrogen fuel cells, solar cells, electric hybrid systems, compressed natural gas (CNG) and CNG hybrid systems alongside the latest proposal of using nuclear batteries. Hydrogen cars have zero emissions from their exhaust and can be refueled quickly, however there are some drawbacks like hydrogen production, storage, and infrastructure. The efficiency, affordability, and scalability of various hydrogen production techniques, fuel cell stack designs and storage technologies (compressed gas, liquid, and metal hydrides) are evaluated in this paper. Solar FCEVs on the other hand, are designed to utilize solar energy like Solar EVs but are very different in their operation and fundamentals
Hebbale Ramkumar, RamyaTrivedi, Shubham
As the world becomes more environmentally conscious, a sustainable transition from Compressed Natural Gas (CNG) to a hydrogen economy is desirable. Hydrogen is a clean and abundant fuel that has the potential to replace fossil fuels and eliminate greenhouse gas emissions. This paper analyses the status of the hydrogen economy and the policies and incentives that government is implementing to promote its adoption, storage, dispensing and usage. The feasibility of a transition from CNG to a hydrogen economy through HCNG and the challenges that need to be overcome are explored. The paper discusses the advantages and disadvantages of CNG, HCNG and hydrogen and compares the fuels in terms of energy efficiency, infrastructure requirements and environmental impact. Efforts have been made to develop Hydrogen storage cylinder (Type IV) to store hydrogen gas at high pressures, typically around 350 to 700 bar (5,000 to 10,000 psi), to ensure a sufficient range for the vehicle and ensure no risk
Vora, Kamalkishore ChhaganlalParasumanna, Ajeet Babu KumarShembekar, Prashant Sharad
Innovation often comes a piece at a time, but what happens when you put all those pieces together at once? That is precisely the question Shell is attempting to answer with its Starship initiative. Now in its third iteration, Starship 3.0 Natural Gas continues pushing the boundaries of efficiency and emissions reduction by employing all currently available technologies and engineering advancements. The Shell Starship initiative was first launched in 2018 with the aim of setting new benchmarks for the commercial road transport sector. The Starship 2.0 managed 254 ton-miles per gallon for freight ton efficiency (FTE), which is 3.5 times the North American average. Additionally, Starship 2.0 recorded fuel consumption of 10.8 mpg on a cross-country run, which according to Shell is nearly double the current fleet average in North America.
Wolfe, Matt
Clean-burning fuels, aftertreatment and other innovations place the heavy-duty combustion engine on a low-carbon emissions trajectory. Agriculture, industrial, mining, construction, freight transport and other major global economy sectors rely on vehicle power to thrive. “Internal combustion engines - those powered by gasoline, diesel, natural gas or propane - really are key to our current economy, and we see [the ICE] as a key part of our energy future,” Allen Schaeffer, executive director of the Engine Technology Forum, a U.S.-based educational organization, said during a September webinar. Hosted by the Engine Technology Forum, the “Taking Internal Combustion Engines to the Next Level” session focused on current and under-development innovations aimed at increasing engine efficiency and lowering emissions.
Buchholz, Kami
The need to reduce vehicle-related emissions in the great cities has led to a progressive electrification of urban mobility. For this reason, during the last decades, the powertrain adopted for urban buses has been gradually converted from conventional Internal Combustion Engine (ICE), diesel, or Compressed Natural Gas (CNG), to hybrid or pure electric. However, the complete electrification of Heavy-Duty Vehicles (HDVs) in the next years looks to be still challenging therefore, a more viable solution to decarbonize urban transport is the hybrid powertrain. In this context, the paper aims to assess, through numerical simulations, the benefits of a series hybrid-electric powertrain designed for an urban bus, in terms of energy consumption, and pollutants emissions. Particularly a Diesel engine, fueled with pure hydrogen, is considered as a range extender. The work is specifically focused on the design of the Energy Management Strategy (EMS) of the series-hybrid powertrain, by comparing
Nacci, GianlucaCervone, DavideFrasci, EmmanueleLAKSHMANAN, Vinith KumarSciarretta, AntonioArsie, Ivan
Hydrogen-powered mobility is believed to be crucial in the future, as hydrogen constitutes a promising solution to make up for the non-programmable character of the renewable energy sources. In this context, the hydrogen-fueled internal combustion engine represents one of the suitable technical solution for the future sustainable mobility. In a short-term perspective, the development of the green hydrogen production capability and distribution infrastructure do not allow a substantial penetration of pure hydrogen IC engines. For this reason, natural gas – hydrogen blends can represent a first significant step towards decarbonization, also determining a trigger effect on the hydrogen market development. The present paper is focused on the analysis of the combustion and performance characteristics of a production PFI natural gas engine, run on blends with 15% in volume of hydrogen (HCNG). More specifically, a fuel-flexible, predictive 1D simulation model has been developed within the
Baratta, MirkoDi Mascio, ValerioMisul, DanielaMarinoni, AndreaCerri, TarcisioOnorati, Angelo
Ammonia, with its significant hydrogen content, offers a practical alternative to pure hydrogen in marine applications and is easier to store due to its higher volumetric energy density. While Ammonia's resistance to auto-ignition makes it suitable for high-compression ratio engines using pre-mixed charge, its low flame speed poses challenges. Innovative combustion strategies, such as dual-fuel and reactivity-controlled compression ignition (RCCI), leverage secondary high-reactivity fuels like diesel to enhance Ammonia combustion. To address the challenges posed by Ammonia's low flame speed, blending with hydrogen or natural gas (NG) in the low reactivity portion of the fuel mixture is an effective approach. For combustion simulation in engines, it is crucial to develop a chemical kinetics mechanism that accommodates all participating fuels: diesel, Ammonia, hydrogen, and NG. This study aims to propose a kinetics mechanism applicable for the combustion of these fuels together. The
Salahi, Mohammad MahdiMahmoudzadeh Andwari, AminKakoee, AlirezaHyvonen, JariGharehghani, AyatMikulski, MaciejLendormy, Éric
The article deals with the peculiarities of developing a method for evaluating the fuel efficiency and environmental performance of vehicle engines under conditions of pre- and post-start thermal preparations. The method was designed for gasoline engines converted to run on both liquid petroleum and gaseous fuels (LPG). A thermal treatment system based on a phase transition heat accumulator was used for pre- and post-start heat treatment in operation. An algorithm for determining and evaluating individual thermal preparation criteria for vehicle engines in operational conditions was developed based on the analysis conducted. The method for assessing fuel consumption and harmful emissions in the exhaust gases of vehicles with engines modified to run on LPG and fitted with a phase transition heat accumulator during pre- and post-start thermal preparations was improved. The method development is based on numerous experimental and computational–analytical studies. To assess the high
Gritsuk, IgorPohorletskyi, DmytroPohorletska, NadiiaVolkov, VladimirVolodarets, MykytaKhudiakov, IgorDotsenko, SerhiiNesterenko, ViktoriiaVolska, Olena
Vibrations in IC engines have a widespread effect on the operations of consumer and commercial vehicles, which not only affect the life and efficiency of the vehicle but also affect user comfort and nervous system of human body. This paper focuses on the comparative analysis of vibration and acoustic characteristics while utilizing fuels such as petrol and CNG. ADXL 335 3-axis accelerometer was employed to measure acceleration vs time data, which was then processed using MATLAB to obtain FFT and PSD plots. These plots thus obtained gave insights on dominating frequency as well as frequencies with maximum energy. Six different cases with different engine speeds and loading conditions are studied with analysis of all the different parameters such as sound pressure levels and mean and max cylinder pressure.
Anasune, Aditya
Hexagon Agility announced a collaboration with Norwegian EV transmission supplier Brudeli Green Mobility at the 2024 ACT Expo in Las Vegas. The partnership's goal is the integration of Hexagon Agility's CNG/RNG (compressed/renewable natural gas) systems with Brudeli's plug-in PowerHybrid system. This technology will reportedly offer fleets the capability to maintain diesel ICE duty cycles while providing fuel cost savings and help OEMs achieve global decarbonization goals. “The Brudeli PowerHybrid enables fleet owners to retain the power, performance and fuel cost savings offered by natural gas engines, while simultaneously harnessing the efficiencies of electric,” said Eric Bippus, EVP sales & systems development, Hexagon Agility. “We believe hybrids could play a role in commercial trucking in the future, and we are excited to take an active role bringing that to the market.”
Wolfe, Matt
Heavy duty engines for long-haul trucks are quite difficult to electrify, due to the large amount of energy that should be stored on-board to achieve a range comparable to that of conventional fuels. In particular, this paper considers a stock engine with a displacement of 12.9 L, developed by the manufacturer in two different versions. As a standard diesel, the engine is able to deliver about 420 kW at 1800 rpm, whereas in the compressed natural gas configuration the maximum power output is 330 kW, at the same speed. Three possible alternatives to these fossil fuels are considered in this study: biodiesel (HVOlution by Eni), bio-methane and green hydrogen. While the replacement of diesel and compressed natura gas with biofuels does not need significant hardware modifications, the implementation of a hydrogen spark ignition combustion system requires a deep revision of the engine concept. For a more straightforward comparison among the alternative fuels, the same engine platform has
Volza, AntonelloPisapia, AlfredoCaprioli, StefanoRinaldini, CarloMattarelli, Enrico
Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO2. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH4 most efficiently usually being supported by metal oxides such as aluminium oxide (Al2O3). Water (H2O) contained in the exhaust gas causes strong inhibition on Pd catalysts. In real exhaust gases, not only water vapour but also pollutants and sulphur-containing compounds such as hydrogen sulphide (H2S) or sulphur oxides (SOx) are poisoning the
Tomin, SebastianWagner, UweKoch, Thomas
In response to global climate change, there is a widespread push to reduce carbon emissions in the transportation sector. For the difficult to decarbonize heavy-duty (HD) vehicle sector, hybridization and lower carbon-intensity fuels can offer a low-cost, near-term solution for CO2 reduction. The use of natural gas can provide such an alternative for HD vehicles while the increasing availability of renewable natural gas affords the opportunity for much deeper reductions in net-CO2 emissions. With this in consideration, the US National Renewable Energy Laboratory launched the Natural Gas Vehicle Research and Development Project to stimulate advancements in technology and availability of natural gas vehicles. As part of this program, Southwest Research Institute developed a hybrid-electric medium-HD vehicle (class 6) to demonstrate a substantial CO2 reduction over the baseline diesel vehicle and ultra-low NOx emissions. The development included the conversion of a 5.2 L diesel engine to
Wallace, JulianMitchell, RobertRao, SandeshJones, KevinKramer, DustinWang, YanyuChambon, PaulSjovall, ScottWilliams, D. Ryan
Fuel system supplier Hexagon Agility is optimistic about the growth of CNG thanks to the introduction of the Cummins X15N engine. Though some OEMs have signaled that the end of the ICE age is nigh, reports of the combustion engine's death as the backbone of the commercial-trucking industry are greatly exaggerated. Battery-electric vehicles are seeing continued growth in various medium-duty and last-mile delivery sectors, but their lack of energy density and cost per have prevented them from gaining market share for Class 6 and larger commercial vehicles in North America. Several suppliers are anticipating that this trend will persist over the coming decades and are making major investments in the development of alternative fuel systems for diesel combustion engines. One such supplier is Hexagon Agility. Based in the northern suburbs of Charlotte, North Carolina, Hexagon recently announced expansion plans of its Salisbury, North Carolina, facility to field orders and installations of
Wolfe, Matt
The Particle Number–Portable Emission Measurement System (PN-PEMS) came into force with Euro VI Phase E regulations starting January 1, 2022. However, positive ignition (PI) engines must comply from January 1, 2024. The delay was due to the unavailability of the PN-PEMS system that could withstand high concentrations of water typically present in the tailpipe (TP) of CNG vehicles, which was detrimental to the PN-PEMS systems. Thus, this study was designed to evaluate the condensation particle counter (CPC)-based PN-PEMS measurement capabilities that was upgraded to endure high concentration of water. The PN-PEMS measurement of solid particle number (SPN23) greater than 23 nm was compared against the laboratory-grade PN systems in four phases. Each phase differs based upon the PN-PEMS and PN system location and measurements were made from three different CNG engines. In the first phase, systems measured the diluted exhaust through constant volume sampler (CVS) tunnel. Data generated
Khan, M. YusufAgarwal, NikhileshPanda, SampadDesai, Atharva TusharWilkinson, John C.Chaille, EvanVats, ShekharSalemme, Tina L.Ragupathy, Thinnesh
This study demonstrates the defossilized operation of a heavy-duty port-fuel-injected dual-fuel engine and highlights its potential benefits with minimal retrofitting effort. The investigation focuses on the optical characterization of the in-cylinder processes, ranging from mixture formation, ignition, and combustion, on a fully optically accessible single-cylinder research engine. The article revisits selected operating conditions in a thermodynamic configuration combined with Fourier transform infrared spectroscopy. One approach is to quickly diminish fossil fuel use by retrofitting present engines with decarbonized or defossilized alternatives. As both fuels are oxygenated, a considerable change in the overall ignition limits, air–fuel equivalence ratio, burning rate, and resistance against undesired pre-ignition or knocking is expected, with dire need of characterization. Two simultaneous high-speed recording channels granted cycle-resolved access to the natural flame luminosity
Mühlthaler, Markus SebastianHärtl, MartinJaensch, Malte
The steam reforming of CH4 plays a crucial role in the high-temperature activity of natural gas three-way catalysts. Despite existing reports on sulfur inhibition in CH4 steam reforming, there is a limited understanding of sulfur storage and removal dynamics under various lambda conditions. In this study, we utilize a 4-Mode sulfur testing approach to elucidate the dynamics of sulfur storage and removal and their impact on three-way catalyst performance. We also investigate the influence of sulfur on CH4 steam reforming by analyzing CH4 conversions under dithering, rich, and lean reactor conditions. In the 4-Mode sulfur test, saturating the TWC with sulfur at low temperatures emerges as the primary cause of significant three-way catalyst performance degradation. After undergoing a deSOx treatment at 600 °C, NOx conversions were fully restored, while CH4 conversions did not fully recover. Experimental data under fixed lambda conditions reveal that sulfur stored on the catalyst leads to
Kim, Mi-YoungDadi, Karthik VenkataGong, JianKamasamudram, Krishna
The internal combustion engine (ICE) has long dominated the heavy-duty sector by using liquid fossil fuels such as diesel but global commitments by countries and OEMs to reduce lifecycle carbon dioxide (CO2) emissions has garnered interest in alternative fuels like hydrogen. Hydrogen is a unique gaseous fuel that contains zero carbon atoms and has desired thermodynamic properties of high energy density per unit mass and high flame speeds. However, there are challenges related to its adoption to the heavy-duty sector as a drop-in fuel replacement for compression ignition (CI) diesel combustion given its high autoignition resistance. To overcome this fundamental barrier, engine manufacturers are exploring dual fuel combustion engines by substituting a fraction of the diesel fuel with hydrogen which enables fuel flexibility when there is no infrastructure and retrofittability to existing platforms. This work studies the implications of mixing port-injected hydrogen fuel in a large-bore
O'Donnell, PatrickKazmouz, SamuelWu, SicongAmeen, MuhsinKlingbeil, AdamLavertu, ThomasJayakar, VijayaselvanSheth, PushkarWijeyakulasuriya, Sameera
The Argon Power Cycle (APC) is a novel zero-emission closed-loop argon recirculating engine cycle which has been developed by Noble Thermodynamics Systems, Inc. It provides a significant gain in indicated thermal efficiency of the reciprocating engine by breathing oxygen and argon rather than air. The use of argon, a monatomic gas, greatly increases the specific heat ratio of the working fluid, resulting in a significantly higher ideal Otto cycle efficiency. This technology delivers a substantial improvement in reciprocating engine performance, maximizing the energy conversion of fuel into useful work. Combined Heat and Power (CHP) operating under the APC represents a promising solution to realize a net-zero-carbon future, providing the thermal energy that hard-to-electrify manufacturing processes need while at the same time delivering clean, dispatchable, and efficient power. Since the working fluid in an APC is synthetic, the concentration of argon, oxygen, fuel, and carbon dioxide
Kim, JoohanScarcelli, RiccardoBeardsell, GuillaumeStrickland, TylerNilsen, ChristopherSierra Aznar, Miguel
This paper presents a comprehensive analysis of emerging powertrain technologies for a wide spectrum of vehicles, ranging from light-duty passenger vehicles to medium and heavy-duty trucks. The study focuses on the anticipated evolution of these technologies over the coming decades, assessing their potential benefits and impact on sustainability. The analysis encompasses simulations across a wide range of vehicle classes, including compact, midsize, small SUVs, midsize SUVs, and pickups, as well as various truck types, such as class 4 step vans, class 6 box trucks, and class 8 regional and long-haul trucks. It evaluates key performance metrics, including fuel consumption, estimated purchase price, and total cost of ownership, for these vehicles equipped with advanced powertrain technologies such as mild hybrid, full hybrid, plug-in hybrid, battery electric, and fuel cell powertrains. Comparative assessments are conducted against conventional gasoline, diesel, and natural gas internal
Islam, Ehsan SabriNieto Prada, DanielaVijayagopal, RamKim, NamdooPhillips, PaulAlhajjar, MichelMansour, CharbelRousseau, Aymeric
Ammonia is one of the carbon-free alternatives considered for power generation and transportation sectors. But ammonia’s lower flame speed, higher ignition energy, and higher nitrogen oxides emissions are challenges in practical applications such as internal combustion engines. As a result, modifications in engine design and control and the use of a secondary fuel to initiate combustion such as natural gas are considered for ammonia-fueled engines. The higher-octane number of methane (the main component in natural gas) and ammonia allows for higher compression ratios, which in turn would increase the engine's thermal efficiency. One simple approach to initiate and control combustion for a high-octane fuel at higher compression ratios is to use a spark plug. This study experimentally investigated the operation of a heavy-duty compression ignition engine converted to spark ignition and ammonia-methane blends. Engine operation at a 40% natural gas energy substitution rate with ammonia was
Alvarez, Luis F.Dumitrescu, Cosmin E.
Exhaust gas recirculation (EGR) is a proven strategy for the reduction of NOX emissions in spark ignited (SI) engines and compression ignition engines, especially in lean burn conditions where the increase of thermal efficiency is obtained. The dilution level of the mixture with EGR is in a conventional SI engine limited by the increase of combustion instability (CoV IMEP). A possible method to extend the EGR dilution level and ensure stable combustion is the implementation of an active pre-chamber combustion system. The pre-chamber spark ignited (PCSI) engine enables fast and stable combustion of lean mixtures in the main chamber by utilizing high ignition energy of multiple flame jets penetrating from the pre-chamber to the main chamber. In this paper, as an initial research step, a numerical analysis is performed by employing the 0D/1D simulation model, validated with the initial experimental and 3D-CFD results. The simulation model is used for the prediction of possible benefits of
Dilber, ViktorKrajnovic, JosipUgrinić, SaraSjeric, MomirTomic, RudolfKozarac, Darko
Diesel-fueled heavy-duty vehicles (HDVs) can be retrofitted with conversion kits to operate as dual-fuel vehicles in which partial diesel usage is offset by a gaseous fuel such as compressed natural gas (CNG). The main purpose of installing such a conversion kit is to reduce the operating cost of HDVs. Additionally, replacing diesel partially with a low-carbon fuel such as CNG can potentially lead to lower carbon dioxide (CO2) emissions in the tail-pipe. The main issue of CNG-diesel dual-fuel vehicles is the methane (CH4, the primary component of CNG) slip. CH4 is difficult to oxidize in the exhaust after-treatment (EAT) system and its slip may offset the advantage of lower CO2 emissions of natural gas combustion as CH4 is a strong greenhouse gas (GHG). The objective of this study is to compare the emissions of an HDV with a CNG conversion kit operating in diesel and dual-fuel mode during highway operation. Road tests were conducted on a three-axle Class-8 highway semi-trailer tractor
Dev, ShouvikQi, AiduAnderson, AndrewDahlseide, AustinSmith, BrettLussier, Simon-AlexandreGuo, HongshengRosenblatt, Deborah
Recent legislation banning the sale of new petrol and diesel vehicles in Europe from 2035 has shifted the focus of internal combustion engine research towards alternative fuels with net zero tailpipe emissions such as hydrogen. Research regarding hydrogen as a fuel is particularly pertinent to the so-called ‘hard-to-electrify’ propulsion applications, requiring a combination of large range, fast refuelling times or high-load duty cycles. The virtual design, development, and optimisation of hydrogen internal combustion engines has resulted in the necessity for accurate predictive modelling of the hydrogen combustion and autoignition processes. Typically, the models for these processes rely respectively on laminar flame speed datasets to calculate the rate of fuel burn as well as ignition delay time datasets to estimate autoignition timing. These datasets are generated using chemical kinetic mechanisms available in the literature. However, these mechanisms have typically been developed
Ribnishki, AleksandarCharles, CameronEsposito, StefaniaAkehurst, SamYuan, Hao
Stoichiometric natural gas (CNG) engines are an attractive solution for heavy-duty vehicles considering their inherent advantage in emitting lower CO2 emissions compared to their Diesel counterparts. Additionally, their aftertreatment system can be simpler and less costly as NOx reduction is handled simultaneously with CO/HC oxidation by a Three-Way Catalyst (TWC). The conversion of methane over a TWC shows a complex behavior, significantly different than non-methane hydrocarbons in stoichiometric gasoline engines. Its performance is maximized in a narrow A/F window and is strongly affected by the lean/rich cycling frequency. Experimental and simulation results indicate that lean-mode efficiency is governed by the palladium’s oxidation state while rich conversion is governed by the gradual formation of carbonaceous compounds which temporarily deactivate the active materials. Lean/rich cycling around stoichiometry enables a higher CH4 oxidation as the oxygen storage seems to balance the
Karamitros, DimitriosIbraimova, AdjerKonstantinidis, KonstantinosKoltsakis, GrigoriosChoi, SungmuCho, Jiho
The depletion of oil resource and change in global warming has led to the development of alternate energy resources. Commercially the LPG gas is used as alternate fuel for the spark ignition engine. In this work an experimental investigation is done on Liquefied Petroleum Gas (LPG) along with dual fuel mode of diesel as an alternative fuel for four stroke compression ignition engines. The primary objective of this study was to analyze the performance and the exhaust emissions of the engine using different LPG flow rate. The engine used in the study was originally a single cylinder, four-stroke compression ignition engine and minor modifications were carried out to permit the experiments to run on LPG fuel. The LPG is supplied in the suction stroke mixed with air while diesel is injected at the end of the compression stroke to initiate the combustion process. The LPG is made to flow with different levels of 3%, 6%, 9%, 12%, 18% and 21% on the volume basis with Diesel 100%. The
Suresh Balaji, R.Daniel Das, A.Marimuthu, S.Manivannan, S.
Customer preference towards quieter vehicles is ever-increasing. Exhaust tailpipe noise is one of the major contributors to in-cab noise and pass-by-noise of the vehicle. This research proposes a silencer with an integrated acoustic valve to reduce exhaust tailpipe noise. Incident exhaust wave coming from the engine strikes the acoustic valve and generates reflected waves. Incident waves and reflected waves cancel out each other which results in energy loss of the exhaust gas. This loss of energy results in reduced noise at the exhaust tailpipe end. To evaluate the effectiveness of the proposed silencer on the vehicle, NVH (Noise, vibration, and harshness) performance of the proposed silencer was compared with the existing silencer which is without an acoustic valve. A CNG (Compressed natural gas) Bus powered by a six-in-line cylinder engine was chosen for the NVH testing. After NVH evaluation, it was found that when using the proposed silencer, overall exhaust tailpipe orifice noise
Singh, Har GovindKhandagale, AnupChoudhari, YogeshwarKalsule, DhanajiPetale, Mahendra
With the advent of upcoming stringent automobile emission norms globally, it is inevitable for original equipment manufacturers (OEMs) to shift towards greener alternatives. Use of compressed natural gas (CNG) is a preferred solution as it is a relatively clean burning fuel and it doesn’t have significant loss in vehicle efficiency and performance. Modern day customers are more aware and sensitive towards vehicle noise, vibration and harshness (NVH). Hence, OEMs must cater to this demand through optimized design and layout. In a passenger vehicle, CNG is stored at high pressure and delivered to injectors after pressure reduction at a regulator. During engine idling, the opening and closing motion of the CNG injector generates back pulsation and these pulsations cause vibrations which may propagate through other components in the delivery path and perceived as noise inside vehicle cabin. To identify the frequencies involved in pressure pulsation, a 1-D simulation of CNG fuel system is
Meena, DeepeshSharma, RohanKhandelwal, AbhishekJadhav, Praveen SinghPai, Devananda
In the past few decades CNG (Compressed Natural Gas) fuel growing as an alternate fuel due to its more economically as compared to Gasoline & Diesel fuels by vehicle running cost in both passenger as well as commercial vehicles, additionally it is more environment friendly & safer fuel with respect to gasoline & diesel. At standard temperature & pressure fuel density of Natural Gas (0.7-0.9 kg/m3) is lower than Gasoline (715-780 kg/m3), Diesel (849~959 kg/m3), therefore CNG fuel require higher storage space as compared to Gasoline & Diesel & also it stores at very high pressure (200-250 bar) to further increase the fuel density 180 kg/m3 (at 200 bar) and for 215 kg/m3 (at 250 bar) in CNG cylinders so that max fuel contains in the cylinders and increase the vehicle running range per fuel filling & reduces its fuel filling frequency at filling stations. Therefore to gain max vehicle running range in a single fuel filling, NGVs (Natural Gas powered vehicles) require more numbers of CNG
Singh, Gaurav KumarKumar, SatishPatil, PraveenSharma, Mukesh
Methane (CH4) is main constituent of compressed natural gas (CNG). CNG is compressed to less than 1% of the volume, which it occupies at atmospheric pressure. CNG contains almost 70% to 90% methane, one of the most significant greenhouse gas contributing directly into climate change. The effects caused due to gas leakages that results in fire and bursting of cylinder can be prevented by continuous monitoring of gas leakage in the Gas transmission pipeline of the commercial vehicles. In order to detect the methane leaks and resolve as early as possible, effective sensors need to be researched, analyzed and developed. This paper discusses about the usage of sensor with digital output replacing the previous gas leak detection sensor module, which gives analog output. The previously used Gas leakage detection module implements a design of a gas leakage detector system with, LED and audio indication that notifies the leakage in gas to the users. A sensor-based device easily detects a CNG
Yadav, SharadJoshi, Anil PrabhakarGaikwad, PrathmeshGaikwad, RohitSangle, Abhijit
Petroleum Oil, Lubricants (POL) & Liquefied petroleum gas (LPG) tanker vehicles are special application segment that holds a significant Market share for commercial vehicles. These vehicles need to comply additional Safety regulations specified by Petroleum and explosives safety organization (PESO). For compliance to Rule-70, Protective heat shield on exhaust system needs to be designed and validated in order to avoid any catastrophic failure. The paper demonstrates the methodology to identify the worst case scenario for the existing commercial vehicle segment. Based on detail digital mock up (DMU) review Metallic heat shield was designed on after treatment system (ATS). The flexible heat shield was designed for exhaust pipe & joints in order to restrain the heat flow to the surrounding aggregates. After finalising design, CFD analysis was carried out to find out the thermal effects on various components and results within acceptable limits. After digital validation proto parts were
Sahoo, RajanikantaKhandagale, AnupManoharan, LogeshwaranKumar, PravinPetale, Mahendra Arvind
Items per page:
1 – 50 of 2282