This experimental study compared a blend of diesel–DEE (DEE 40% v/v in diesel) with baseline diesel. This experimental study assesses different fuel injection strategies for controlling the in-cylinder charge stratification, such as single, double, and triple injections. The peak in-cylinder pressure under the partially premixed combustion mode was higher than conventional diesel combustion. Higher in-cylinder pressure with increasing dwell time was observed under triple injections. Retarding pilot injections increased the peak in-cylinder pressure. Conventional diesel combustion mode exhibited the highest brake thermal efficiency and lowest emissions with all injection strategies. A longer dwell time of 12° CA showed higher brake thermal efficiency, nitric oxide, and carbon monoxide emissions, whereas hydrocarbon emissions were lower compared to a shorter dwell time of 6° CA. Hydrocarbon and carbon monoxide emissions increased, but nitric oxide and brake thermal efficiency were

Sonawane, Utkarsha, Agarwal, Avinash Kumar

Computational Investigation on a Boosted Uniflow Scavenged Direct-Injection Combustion Engine (BUSDICE) with Alcohol Fuels

2025-32-0027

11/03/2025

Alcohol fuels, produced from renewable energy sources, are considered a crucial solution for achieving life-cycle carbon neutrality in internal combustion engines. The Boosted Uniflow Scavenged Direct-Injection Combustion Engine (BUSDICE) exhibits significant potential for high thermal efficiency with an aggressive downsizing design. In this study, a computational investigation was carried out to assess the spray mixing and combustion characteristics of BUSDICE fuelled with methanol and ethanol, compared with gasoline, under a high-load condition. The injection duration of methanol and ethanol is significantly longer than that of iso-octane, leading to incomplete evaporation. The mixture exhibits an “outer-rich, central-lean” stratification pattern due to the short mixing time and swirl flow transportation for all three fuels. However, the prolonged injection of methanol induces stronger turbulence, which can enhance the local mixing. The spatial mixture stratification, particularly

Feng, Yizhuo, Lu, Enshen, Dong, Shuo, Keshtkar, Hossein, Wang, Xinyan, Zhao, Hua

Analysis of Flame Propagation Characteristics in a Hydrogen Engine using an Optically Accessible Engine

2025-32-0061

11/03/2025

This study focused on the effects of hydrogen on the flame propagation characteristics and combustion characteristics of a small spark-ignition engine. The combustion flame in the cylinder was observed using a side-valve engine that allowed optical access. The fundamental characteristics of hydrogen combustion were investigated based on combustion images photographed in the cylinder with a high-speed camera and measured cylinder pressure waveforms. Experiments were conducted under various ignition timings and equivalence ratios and comparisons were made with the characteristics of an existing hydrocarbon liquid fuel. The hydrogen flame was successfully photographed, although it has been regarded as being difficult to visualize, thus enabling calculation of the flame propagation speed. As a result, it was found that the flame propagation speed of hydrogen was much faster than that of the existing hydrocarbon fuel. On the other hand, it was difficult to photograph the hydrogen flame

Arai, Yuto, Ueno, Takamori, Suda, Ryosuke, Sato, Ryoichi, Nakao, Yoshinori, Ninomiya, Yoshinari, Matsushita, Koichiro, Kamio, Tomohiko, Iijima, Akira

Effect of Plasma-Assisted Ignition on Combustion and Emission Characteristics of Two Stroke Engines with Different Fuels

2025-32-0030

11/03/2025

This study explores the effect of plasma-assisted ignition (PAI) on combustion stability and emissions in two-stroke spark-ignition engines. Two engine platforms were evaluated: a conventional single-cylinder two-stroke engine and a thermodynamically advanced opposed-piston two-stroke (OP2S) engine. The OP2S engine configuration offers reduced heat loss and higher power density due to its uniflow scavenging and favorable geometry, but suffers from high residual gas fraction, which increases ignition difficulty and combustion instability. To address this, nanosecond-pulsed PAI was applied in various spatial arrangements and discharge voltages, using both gasoline and a low-reactivity gasoline/DMC blend fuel. Spark ignition timing was held constant at the minimum advance for best torque across all tests. Combustion stability was assessed via indicated mean effective pressure (IMEP) and its coefficient of variation, while CO and HC emissions were measured as environmental indicators

Liu, Jinru, Yamazaki, Yoshiaki, Otaki, Yusuke, Kato, Hayato, Kobayashi, Daichi, Umegaki, Tetsuo, Asai, Tomohiko, Iijima, Akira

First Investigation of Ducted Fuel Injection on a Retrofitted Heavy-Duty Multi-Cylinder Production Engine

04-19-01-0005

10/22/2025

Ducted fuel injection (DFI) was tested for the first time on a production multi-cylinder engine. Design-of-experiments (DoE) testing was carried out for DFI with a baseline ultra-low sulfur diesel (ULSD) fuel as well as three fuels with lower lifecycle carbon dioxide (CO2) emissions: renewable diesel, neat biodiesel (from soy), and a 50/50 blend by volume of biodiesel with renewable diesel denoted B50R50. For all fuels tested, DFI enabled simultaneous reductions of engine-out emissions of soot and nitrogen oxides (NOx) with late injection timings. DoE data were used to develop individual calibrations for steady-state testing with each fuel using the ISO 8178 eight-mode off-road test cycle. Over the ISO 8178 test, DFI with a five-duct configuration and B50R50 fuel reduced soot and NOx by 87% and 42%, respectively, relative to the production engine calibration. Soot reductions generally decreased with increasing engine load. Hydrocarbon and carbon monoxide emissions tended to increase

Ogren, Ryan M., Baumgard, Kirby J., Radhakrishna, Vishnu, Kempin, Robert C., Mueller, Charles J.

Optimal Sets of Molecules to Predict Aviation Fuel Properties

2025-01-0395

10/07/2025

The complexity and variability of modern aviation fuels necessitate the development of robust and efficient tools to assess their properties accurately, particularly within the certification framework established by the American Society for Testing and Materials (ASTM). Therefore, previous research has developed predictive models to reduce the experimental burden by predicting aviation fuel properties from broad chemical classes. While two-dimensional Gas Chromatography (GC×GC) provides detailed compositional information, it only identifies the weight of hydrocarbon families (aromatics, cycloalkanes, n-alkanes, iso-alkanes), not individual molecules. Aviation fuels are complex, and their composition can contain more than 60 key classes, the majority of which are isomeric. As a result, an exceptionally high number of possible molecule combinations makes random selection prone to high errors in property prediction. To this end, we used a Monte Carlo approach to search for the optimal

Radaideh, Mohammed I., Kim, Doohyun, Radaideh, Majdi, Violi, Angela

Experimental and Numerical Insights on Emissions Control with a Diesel Oxidation Catalyst in Reactivity-Controlled Compression Ignition Combustion Conditions

03-18-05-0034

09/01/2025

Reactivity-controlled compression ignition (RCCI), a low-temperature combustion strategy, reduces oxides of nitrogen (NOx) and soot simultaneously; however, high concentrations of carbon monoxide (CO) and total hydrocarbons (THC) and low exhaust gas temperatures pose a significant challenge for the catalytic control of tailpipe CO and THC. Diesel oxidation catalyst (DOC) is generally used in compression ignition (CI) engines for CO, THC, and nitric oxide (NO) oxidation. This work provides a new understanding of the performance characteristics of a DOC in the RCCI combustion strategy with various gasoline–diesel fuel premix ratios ranging from ~46% to ~70% at steady-state operating conditions. Experimental insights from the RCCI strategy prompt considerations of both CO and THC oxidations and THC trap functionalities in the 1D transient model of the DOC. It is observed that an increase in the fuel premix ratio from 50% to 70% in RCCI shifts the CO and THC oxidation characteristics

Suman, Abhishek, Sarangi, Asish Kumar, Herreros, Jose Martin

Drop-In Performance of Propyl- and Butyl-Terminated Oxymethylene Ethers in a Compression Ignition Engine

04-19-01-0003

07/16/2025

Oxymethylene ethers (OMEs) have been proposed for use in diesel engines as a high-reactivity fuel with reduced soot emission. Historically, the focus on methyl-terminated OMEs has limited drop-in applicability. In this work, a set of extended-alkyl OMEs with methyl, propyl, and butyl terminations are tested in an unmodified 4.5L Deere diesel engine, neat and in various blends with ultra-low-sulfur diesel (ULSD). Engine operability and emissions data are collected for the various fuel blends. External laboratory testing against the ASTM D975 standard demonstrates that a blend of 30% butyl-terminated OMEs with ULSD meets all ASTM standard requirements except lubricity. It is shown that the OMEs and OME–diesel blends demonstrate shorter combustion durations, as defined by the 10%–90% heat release timing, than the ULSD control. Engine brake efficiency is unaffected by OME usage, while specific fuel consumption increases in proportion to the reduced heating values of OMEs. Particulate

Lucas, Stephen P., Zdanowicz, Andrew, Wolff, Wyatt W., Windom, Bret

Effect of Water Dilution and Homogenous Lean Operation on Combustion and Detailed Emissions in a Spark Ignited Gasoline Direct Injection Engine

04-19-01-0004

07/10/2025

Twenty-nine percent of the greenhouse gas emissions in the US are produced by the transportation sector according to the US Environmental Protection Agency. The combination of increasingly stringent regulations on emissions and fuel economy, along with the current practical limitations of electrification motivate continued development efforts for improving internal combustion engine efficiency and emissions. Ethanol, an extensive fuel additive or drop-in replacement for gasoline, is already recognized as a promising transition fuel in decarbonization efforts. Furthermore, lean combustion in spark-ignited (SI) engines has been pursued extensively for engine efficiency and emissions improvements. Lean combustion, however, faces the challenges of decreased combustion stability and strong increases to engine-out NOx at conditions where conventional SI engines are stable (ϕ > 0.7). Water dilution, historically used as a knock inhibitor in performance engines, has shown potential for

Voris, Alex, Lundberg, Matt, Puzinauskas, Paulius

Effects of Double Injection Strategy in a Diesel-Ammonia Dual-Fuel Engine

2025-01-0206

06/16/2025

This study investigates the application of a double injection strategy in a single-cylinder marine diesel-ammonia dual-fuel engine retrofitted for experimental analysis. A diesel micro-pilot (MP) injection was used to ignite ammonia combustion, and diesel and ammonia were injected separately into the cylinder through dedicated injectors. The first MP injection timing was fixed at reference injection timing, and both early and late double MP injection strategies were implemented to evaluate their effects on ammonia combustion, engine performance, and exhaust emissions. Under all conditions, the ammonia injection timing remained constant. Early double injection strategies, with the second MP injection occurring before the first, enhanced premixed diesel combustion by raising in-cylinder temperature and pressure. However, this early heat release was ineffective for ammonia evaporation and combustion due to poor timing alignment. In contrast, late double injection strategies, with the

Park, Chansoo, Jang, Ilpum, Park, Cheolwoong, Kim, Minki, Park, Gyeongtae

Effect of Ignition Condition and Fuel Octane Number on Knock Intensity in a Small 2-Stroke Engine

2025-01-0211

06/16/2025

Internal combustion engines (ICEs) remain widely used in automotive transportation for their high energy storage system efficiency and economic benefits. The 4-stroke engine has dominated all other forms to date, because the Otto cycle is relatively simple to understand. However, the significant benefits such as less pumping work and friction, lighter construction of 2-stroke engine, are attractive for applications that prioritize the simplicity and power density as well as meet the emission regulations. The disadvantages of the 2-stroke engine are mainly caused by the lack of sufficient scavenging process. Also, the overlap of the intake and exhaust phases results in charge short-circuiting, more fuel consumption and high unburned hydrocarbon emissions. For these reasons, it is difficult for 2-stroke engines to achieve stoichiometric combustion, making them incompatible with three-way catalyst to control emissions. The residual exhaust gas in the cylinder makes the spark ignition

Liu, Jinru, Yamazaki, Yoshiaki, Otaki, Yusuke, Kato, Hayato, Yokota, Takumi, Iijima, Akira

Investigating Lubricants Base Oils Reactivity in Ammonia Engines via Accelerated Aging

2025-01-0240

06/16/2025

As a carbon-free molecule, ammonia is more and more considered as a relevant fuel for long distance and off-road applications. However, this gas has different combustion characteristics compared to conventional fuels, challenging the suitability of lubricants to such engines. In this work, the evolution of lubricants under conditions mimicking ammonia combustion was assessed. Mineral and polyester lubricant base oils were exposed to oxygen, nitrogen oxides, and ammonia in a pressurized reactor under stirring. Oil aliquots were sampled at regular intervals, and characterized using Fourier Transform Infrared Spectroscopy (FTIR), viscosity and total oxygen and nitrogen contents measurements. Exposure to air containing nitrogen oxides resulted in quicker accumulation of oxidation products compared to neat air, for both the mineral and complex polyester base oil. Besides, exposure to gaseous ammonia in air resulted in a slower oxidation rate for both oils, compared to neat air. A global

Doncoeur, Carole, Giarracca, Lucia, Cologon, Perrine, Rousselle, Christine

Understanding How Blending Different Ratios of Renewable Fuels with Diesel Impacts the Toxicity of Exhaust Particulates to Human Health

2025-01-0207

06/16/2025

The urgent need to decarbonise transport has increased the utilisation of renewable fuels blended with current hydrocarbons. Heavy duty vehicle electrification solutions are yet to be realised and therefore the reliance on diesel engines may still be present for decades to come. Currently, the diesel supplied to fuel stations across the UK is a 7% blended biodiesel, whilst in South Korea a 5% blend is utilised. Biodiesel is produced from renewable sources, for example, crops, waste residue, oils and biomass. Particulates from diesel combustion are known to be toxic due to the presence of polycyclic aromatic hydrocarbons (PAHs), however there is very limited understanding of blending oxygenated fuels on the toxicity of the particulates produced. PAHs are aromatic structures that can be metabolised into chemicals which can disrupt DNA replication and potentially influence cancer mechanisms if inhaled in high quantities. Soyabean methyl-ester (SME) was blended at lower ratios, e.g., 5

Hailwood, Emma, Hellier, Paul, Ladommatos, Nicos, Leonard, Martin

Thermal Efficiency Improvement and Emission Reduction of Methanol Spark Ignition Engine Using Lean-Burn Strategy

2025-01-0224

06/16/2025

Methanol is a promising fuel for achieving carbon neutrality in the transportation sector, particularly for internal combustion engine vehicles. With its high-Octane number, methanol enables higher thermal efficiency compared to gasoline engines. Additionally, its wide flammability range allows stable engine operation under lean burn conditions at low to mid-load levels. These characteristics make methanol well-suited for lean-burn strategies, which reduce pumping losses and enhance thermal efficiency. However, there remains a lack of studies on the influence of injection timing under different lean conditions, particularly in a wall-guided spark ignition engine. Wall-guided systems use the chamber wall or piston surface to redirect and stratify the fuel-air mixture near the spark plug at the time of ignition. The combustion performance of lean-burn engines in highly sensitive to variations in injection and excess air ratio. In this study, experiments were conducted on a single

Lee, Seungwon, Kim, Hyunsoo, Hwang, Joonsik, Bae, Choongsik

Research on Basic Characteristics of a Two-Stroke Opposed Piston Engine

2024-32-0112

04/18/2025

This study investigated the performance characteristics of a two-stroke opposed piston engine that is capable of constantly operating with high power output and high efficiency. An investigation was also made of the performance obtained by applying a pseudo uniflow condition as a measure against large hydrocarbon (HC) emissions owing to blow-by of unburned mixture, which is an issue of two-stroke engines. The test engine had a displacement of 127 cm3 and a bore and stroke of 48 x 70 mm. One-point and dual-point ignition systems were used, and regular gasoline was supplied as the test fuel using a carburetor-based fueling system. Experiments were conducted at engine speeds of 1500 and 3000 rpm at ignition timings of 45 deg. and 35 deg. before top dead center. The results showed that large quantities of HC emissions were emitted because stable combustion was not achieved. This revealed that a stronger uniflow condition must be applied as a countermeasure rather than a simple pseudo

Fukushima, Shumpei, Uehara, Ryota, Hayashi, Yoshiaki, Igarashi, Ryo, Tokita, Kazuho, Iijima, Akira

Influence of Methanol-to-Gasoline Fuel Formulation on Knock Propensity and Flame Speed

2025-01-8400

04/01/2025

Drop-in gasoline fuels that originate from renewable, low-net-carbon sources, such as methanol-to-gasoline (MTG), are an important bridge in the transition between traditional fossil fuels and electrification of the transportation sector. The composition of these fuels can be tuned by adjusting the settings of the chemical processes used to create them, which can be leveraged to formulate optimized fuels for higher knock resistance or higher flame speed. This study investigated how the distribution of hydrocarbon classes and molecular structure of a renewable MTG gasoline surrogate affected knock and flame speed using chemical kinetic modeling. The original MTG surrogate was modified by increasing the relative amount of a certain hydrocarbon class while the concentration of other hydrocarbon classes is reduced equally. Increasing normal- and iso-alkanes increased reactivity and penalized octane sensitivity, olefins increased octane sensitivity while keeping the research octane number

MacDonald, James, Lopez Pintor, Dario, Matsubara, Naoyoshi, Kitano, Koji, Yamada, Ryota

Comparison of Gasoline Particulate Indices Using U.S. Market Gasoline Samples

2025-01-8449

04/01/2025

Simulated distillation (SimDis) uses wide bore capillary gas chromatography (GC) to provide a detailed volatility profile of blended gasoline. The boiling point distribution from SimDis analysis is correlated to the hydrocarbon contents of spark ignition fuels and provide the resolution necessary to characterize the compositions of the fuel. Recent publications on simulated distillation applied to spark ignition fuel reveal the merits of indexing a gasoline fuel so that it can be correlated to the tendency of particulate emissions from vehicles. With this in mind, SimDis can be a useful and quick tool in assessing the PM-formation potential of market gasolines. Heavy aromatic compounds are compounds identified as having at least 10 Carbons and 1 aromatic ring. These compounds that are present in spark ignition fuels are major contributors to vehicle particulate emissions. These compounds can be found in the higher boiling portion (T70+) of the distillation profiles. As demonstrated in

Goralski, Sarah, Geng, Pat, Dozier, Jon, Butler, Aron

Products of Tomorrow

TBMG-52824

04/01/2025

Effects of Post-Injection Strategy on the Performance of Diesel Catalyst-Heating Operation

2025-01-8414

04/01/2025

Minimizing the time needed to achieve light-off temperatures in diesel engine aftertreatment devices is key to mitigate pollutant emissions during the first minutes of operation. Catalyst heating operation typically includes one or multiple post-injections late during the expansion stroke aimed to increase the enthalpy of the exhaust gases. However, post-injection retardability is constrained by low combustion efficiency and the formation of CO and unburned hydrocarbons that cannot be oxidized by a still-inactive oxidation catalyst. In this study, the effects of post-injection strategy on the performance and emissions of a medium duty diesel engine have been investigated experimentally, focusing on the impacts on post-injection retardability. A five injection strategy (two pilot, one main, two post) was implemented in the engine, and the injection duration ratio between the two post-injections has been varied systematically while performing post-injection timing sweeps to identify the

Lopez Pintor, Dario, Lee, Sanguk, Cho, Seokwon, Busch, Stephen, Wu, Angela, Narayanan, Abhinandhan, Abboud, Rami

A Computational Investigation of Hydrogen Pre-Chamber and Spark-Ignition Combustion Engines at Different Load Conditions

2025-01-8406

04/01/2025

Pre-chamber (PC) technology has demonstrated its capability to achieve clean and stable combustion in internal combustion engines (ICEs) under lean conditions. This study evaluates the effectiveness of PC in direct injection (DI) hydrogen (H2)-ICEs compared to conventional spark ignition (SI) operation using high-fidelity computational fluid dynamics simulations across a range of load conditions. Various loads were attained by systematically adjusting intake pressure and injected H2 mass. The primary hypothesis posits that highly turbulent PC jets facilitate rapid mixing and combustion of ultra-lean mixtures. The comparative analysis revealed that DI fueling in both PC and SI modes did not achieve perfectly homogeneous mixtures, particularly under high load conditions, although PC slightly enhanced mixture uniformity. Combustion behavior exhibited a non-monotonic trend, with SI outperforming PC at low and high loads, while PC demonstrated superior performance at medium loads despite

Menaca, Rafael, Liu, Xinlei, Mohan, Balaji, Cenker, Emre, AlRamadan, Abdullah, Im, Hong

Combustion and Emission Analysis of Pelletized vs. Raw Biomass Fuels

2025-28-0035

02/07/2025

Biomass fuels, such as sawdust and groundnut shells, are increasingly recognized as sustainable alternatives to fossil fuels. However, their high moisture content and loose structure result in low thermal efficiency. To improve performance, pellet forms of these fuels are often used. Naturally available raw and pellet forms of Sawdust, groundnut shell fuels have been utilized in this study. This study evaluates and compares the thermal efficiency of a gasifier cook stove and emissions from the combustion of raw and pellet forms of biomass fuels. It was found that the burning rate and firepower increase significantly with the use of pellet from of fuels. Sawdust pellets exhibited a highest thermal efficiency of 22.41%. The hydrocarbon (HC) levels for groundnut shell pellets were observed to range between 1 and 5 parts per million (ppm), while for sawdust pellets, it was observed to range from 1 to 6 ppm, indicating the preferable usage of pellets as fuel over raw form of biomass fuel.

Prasad, Malladi Jogendra, Vangipurapu, Bapi Raju

Effects of Injection Parameters On the Evaporation, Mixing, Combustion and Emission Characteristics of a Spark Ignition Methanol Engine

2025-01-7119

01/31/2025

The combustion performance test under different injection parameters was carried out on an inline 6-cylinder spark-ignition (SI) methanol engine, and the influence mechanism of injection parameters on methanol evaporation, mixing, combustion and emission was revealed through simulation. The results indicate that compared to the low-flow nozzle scheme (14*D0.26), when adopting the high-flow nozzle scheme (16*D0.30), the injection duration is shorter. The evaporation rate of methanol in the intake port is increased, the amount of methanol droplets and wall-attached liquid film in the cylinder is reduced, and the temperature in the cylinder is elevated. Moreover, the changes are more significant under high-load operating conditions. The change in the methanol charge rate during the intake process leads to a slightly higher inhomogeneity of the in-cylinder mixture. The relatively high temperature in the cylinder and the appropriate increase in the mixture concentration on the exhaust side

Zhang, Zhi, Liu, Haifeng, Li, Yongzhi, Chang, Weide, Shu, Zanqiao, Ju, Chengyuan, Ratlamwala, Tahir Abdul Hussain, Yao, Mingfa

Exploring the Future of Sustainable Fuels: Experimental and Predictive Insights on Engine Performance and Emissions Using Algae Biodiesel Blends

2024-01-5250

01/28/2025

This study investigates the potential of biodiesel derived from Azolla algae as an alternative fuel for conventional diesel. The performance and emissions characteristics of various biodiesel blends were evaluated experimentally. The physicochemical properties of pure diesel (D100), and blends with Azolla biodiesel at 5% (BD5), 10% (BD10), 15% (BD15), 20% (BD20), and 100% (B100) were analyzed. It is observed that the amount of fuel consumed is higher at higher loads when fuel is blended with biodiesels. Hydrocarbon emissions were reduced with biodiesel blends at full load and the reduction is higher with increase in blend concentration. A significant difference of 85 ppm NOx was observed between BD20 and D100 at full load. CO emissions decreased with higher biodiesel concentrations, with BD20 resulted less CO emissions than D100, making BD20 a more environmentally viable fuel. Artificial neural networks (ANN) were employed for predictive modeling, achieving approximately 95% accuracy

Senthilkumar, D., Murugesan, Sivanesan, Bhadrinath, P., Shamitha, G., Adityasree, R.

Effect of Fuel Chemical Structure on Soot Formation in Sustainable Aviation Fuels

2024-01-4310

11/05/2024

Sustainable Aviation Fuels (SAFs) offer great promises towards decarbonizing the aviation sector. Due to the high safety standards and global scale of the aviation industry, SAFs pose challenges to aircraft engines and combustion processes, which must be thoroughly understood. Soot emissions from aircrafts play a crucial role, acting as ice nuclei and contributing to the formation of contrail cirrus clouds, which, in turn, may account for a substantial portion of the net radiative climate forcing. This study focuses on utilizing detailed kinetic simulations and soot modeling to investigate soot particle generation in aero-engines operating on SAFs. Differences in soot yield were investigated for different fuel components, including n-alkanes, iso-alkanes, cycloalkanes, and aromatics. A 0-D simulation framework was developed and utilized in conjunction with advanced soot models to predict and assess soot processes under conditions relevant to aero-engine combustion. The simulations

Yi, Junghwa, Manin, Julien, Wan, Kevin, Lopez Pintor, Dario, Nguyen, Tuan, Dempsey, Adam

Ionization Based Sensor for Early Detection of Thermal Runaway Events in Lithium-Ion Batteries

2024-01-4326

11/05/2024

Lithium-ion and lithium-metal battery cells are susceptible to a phenomenon known as thermal runaway under failure conditions. Given their widespread use in applications such as electric vehicles, portable electronics, and energy storage systems, early detection of thermal runaway is crucial for ensuring the safety of these battery systems. Thermal runaway entails a rapid escalation in battery cell temperature accompanied by the emission of flammable lithium ions, particulates, electrons, hydrocarbons, and hydrogen gases. These gases pose a significant ignition risk, potentially leading to fires and endangering occupants and bystanders. Therefore, the timely detection of thermal runaway is paramount for ensuring safety in proximity to such battery systems. Traditionally, thermal runaway sensors comprise intricate assemblies of pressure, temperature, and gas sensors, strategically positioned at the pressure relief valve of battery modules. Calibration of all sensors is essential to

Mansour, Youssef

Effects of Fuel Distillation Characteristics on the Performance of Catalyst-Heating Operation in a Medium-Duty Off-Road Diesel Engine

2024-01-4278

11/05/2024

Catalyst heating operation in compression-ignition engines is critical to ensure rapid light-off of exhaust catalysts during cold-start. This is typically achieved by using late post injections for increased exhaust enthalpy, which retardability is constrained by acceptable CO and unburned hydrocarbons emissions, since they are directly emitted through the tailpipe due to the inactivity of the oxidation catalyst at these conditions. Post-injection retardability has shown to be affected by the cetane number of the fuel, but it is unclear how other fuel properties affect the ability to retard the combustion. This study aims to understand the impact of the distillation characteristics of the fuel on the performance of catalyst heating operation and on post-injection retardability. In this study, experiments are performed in a single-cylinder medium-duty diesel engine fueled with three full boiling-range diesel fuels with different distillation curves using a five-injection strategy (two

Lee, Sanguk, Lopez Pintor, Dario, Cho, Seokwon, Busch, Stephen

Quantifying Environmental and Health Impacts of Conventional Diesel and Methane Diesel RCCI Engine Emissions: A Numerical Analysis

2024-01-4307

11/05/2024

A reactivity-controlled compression ignition (RCCI) engine offers ultralow soot and nitrogen oxide (NOx) emission in addition to higher thermal efficiency than diesel or compression ignition (CI) engines. However, the higher emissions of unburned hydrocarbons (HC) and carbon monoxide (CO) from RCCI engines pose a significant challenge that hinders their adoption in the future automotive sector. Additionally, HC includes several hydrocarbons that harm human health and the environment. This study aims to minimize HC and CO formation and emissions by implementing different injection strategies, including adjustments to spray angle configuration, injection timing, and fuel premixing ratio. Additionally, the study examines how different injection strategies affect the spatial and temporal distribution of HC and CO inside the combustion chamber. To achieve this objective, a numerical investigation is conducted on a single-cylinder diesel engine modified to operate in RCCI mode, utilizing a

Yadav, Neeraj Kumar, Chandel, Amit Singh, Maurya, Rakesh Kumar, Padhee, Srikant Sekhar

HYPERFIRE: A Sub-Scale Non-Reacting Flow Test System

TBMG-51750

10/01/2024

Engineers at NASAs Stennis Space Center have developed the HYdrocarbon Propellants Enabling Reproduction of Flows in Rocket Engines (HYPERFIRE), a sub-scale, non-reacting flow test system. HYPERFIRE uses heated ethane to enable physical simulation of rocket engines powered by a broad range of propellants in an inexpensive, accurate, and simple fashion.

Aerospace - General Requirements for Hydraulic Fuse - Quantity Measuring

AS5466 (Current)

06/24/2024

This specification establishes the design, performance, and test requirements for hydraulic quantity measuring fuses intended to be used for hydraulic circuit protection.

A-6C5 Components Committee

Engine Behavior Analysis on a Conventional Diesel Engine Powered with Blends of Lemon Grass Oil Biodiesel–Diesel Blends

03-17-08-0058

06/14/2024

Fossil fuel usage causes environmental pollution, and fuel depletion, further affecting a country’s economy. Biofuels and diesel-blended fuels are practical alternatives to sustain fossil fuels. This experimental study analyses lemongrass oil’s performance, emissions, and combustion characteristics after blending with diesel. Lemongrass oil is mixed with diesel at 10 (B10), 15 (B15), and 25% (B25) and evaluated using a 5.20 kW direct injection diesel engine. B10 brake thermal efficiency is 36.47%, which is higher than other blends. The B10 displays an 8.73% decrease in brake-specific fuel consumption compared to diesel. An increase in exhaust gas temperature for B10 than diesel is 4.5%. It indicates that higher lemongrass oil blends decrease exhaust gas temperature. The decrease in average carbon monoxide emissions in B10 to diesel is 22.19%. The decrease in hydrocarbon emissions for B10 to diesel is 7.14%. Biodiesel with lemongrass oil increases nitrogen oxide (NOx) because of

Swami Punniakodi, Banumathi Munuswamy, Arumugam, Chelliah, Suyambazhahan, Sivalingam, Senthil, Ramalingam, Balasubramanian, Dhinesh, Papla Venugopal, Inbanaathan, Nguyen, Van Nhanh, Cao, Dao Nam

Effects of Renewable Fuels on the Performance and Emissions of a Small Displacement Diesel Engine for Urban Mobility

2024-37-0019

06/12/2024

In the frame of growing concerns over climate change and health, renewable fuels can make an important contribution to decarbonizing the transport sector. The current work presents the results of an investigation into the impact of renewable fuels on the combustion and emissions of a turbocharged compression-ignition internal combustion engine. An experimental study was undertaken and the engine settings were not modified to account for the fuel's chemical and physical properties, to analyze the performance of the fuel as a potential drop-in alternative fuel. Three fuels were tested: mineral diesel, a blend of it with waste cooking oil biodiesel and a hydrogenated diesel. The analysis of the emissions at engine exhaust highlights that hydrogenated fuel is cleaner, reducing CO, total hydrocarbon emissions, particulate matter and NOx.

Chiavola, Ornella, Matijošius, Jonas, Palmieri, Fulvio, Recco, Erasmo

Catalytic Converter—An Integrated Approach to Reduce Carbon Dioxide Emission

2024-01-5047

04/22/2024

Vehicle emissions, which are rising alarmingly quickly, are a significant contributor to the air pollution that results. Incomplete combustion, which results in the release of chemicals including carbon monoxide, hydrocarbons, and particulate matter, is the main cause of pollutants from vehicle emissions. However, CO2 contributes more than the aforementioned pollutants combined. Carbon dioxide is the main greenhouse gas that vehicles emit. For every liter of gasoline burned by vehicles, around 2,347 grams of carbon dioxide are released. Therefore, it’s important to reduce vehicle emissions of carbon dioxide. The ability of materials like zeolite and silicon dioxide to absorb CO2 is outstanding. These substances transform CO2 into their own non-polluting carbonate molecules. Zeolite, silicon dioxide, and calcium oxide are combined to form the scrubbing material in a ratio based on their increasing adsorption propensities, along with enough bentonite sand to bind the mixture.

Saravanakumar, L., Arunprasad, S.

Methane Conversion in Stoichiometric Natural Gas Engine Exhaust

2024-01-2632

04/09/2024

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, Dimitrios, Ibraimova, Adjer, Konstantinidis, Konstantinos, Koltsakis, Grigorios, Choi, Sungmu, Cho, Jiho

Modeling of Vent Gas Composition during Battery Thermal Runaway

2024-01-2199

04/09/2024

The growing global adoption of electric vehicles (EVs) emphasizes the pressing need for a comprehensive understanding of thermal runaway in lithium-ion batteries. Prevention of the onset of thermal runaway and its subsequent propagation throughout the entire battery pack is one of the pressing challenges of lithium-ion batteries. In addition to generating excess heat, thermal runaway of batteries also releases hazardous flammable gases, posing risks of external combustion and fires. Most existing thermal runaway models in literature primarily focus on predicting heat release or the total amount of vent gas. In this study, we present a model capable of predicting both heat release and the transient composition of emitted gases, including CO, H2, CO2, and hydrocarbons, during thermal runaway events. We calibrated the model using experimental data obtained from an 18650 cell from the literature, ensuring the accuracy of reaction parameters. We employ this developed model to investigate

Hariharan, Deivanayagam, Gundlapally, Santhosh

NH ₃ and H ₂ Impact on Combustion and Emission Characteristics of i-C ₈ H ₁₈ Flame under Premixed and Diffusion Conditions

2024-01-2370

04/09/2024

Soot and carbon dioxide released from internal combustion engines became the key issues when using fossil fuels. Ammonia and hydrogen having zero-carbon species can reduce carbon-related emissions and enhance the reliance on renewable fuels. A comparative study of ammonia and hydrogen impact on combustion and emission characteristics of iso-octane flame was performed under different combustion conditions. Arrhenius equation, soot surface reactions, and modified kinetic mechanism were used to study the flame growth, soot nucleation, and surface growth rates. The results show that hydrogen increased the temperature about 20.74 K and 59.30 K, whereas ammonia reduced it about 82.17 K and 66.03 K at premixed and counterflow conditions, respectively. The flame speed of iso-octane was increased 43.83 cm/s by hydrogen and decreased 34.36 cm/s by ammonia. A reduction in CH2O caused a reduction in CO and CO2 emissions. Ammonia impact on CO reduction was stronger than hydrogen under premixed and

Akram, M. Zuhaib, Rashid, Haroon, Deng, Yangbo, Aziz, Muhammad, Zhu, Qiao, Akram, M. Waqar

Improved Coated Gasoline Particulate Filters for China 7 and US Tier 4 Legislations

2024-01-2387

04/09/2024

The impending emission regulations in both China (CN7) and the United States (Tier 4) are set to impose more stringent emission limits on hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM). CN7 places particular emphasis on reducing particulate number (PN) thresholds, while the forthcoming United States Tier 4 legislation is primarily concerned with reducing the allowable particulate matter (PM) to an assumed limit of 0.5 mg/mile. Given the more stringent constraints on both PN and PM emissions, the development of enhanced aftertreatment solutions becomes imperative to comply with these new regulatory demands. Coated Gasoline Particulate Filters (cGPFs) play a pivotal role as essential components for effective PN and PM abatement. These filters are typically deployed in one of two configurations: close-coupled to the turbocharger positioned downstream of a primary three-way catalyst (TWC) or located further downstream of the exhaust system in an

Schoenhaber, Jan, Kawashima, Shota, Gotthardt, Meike, Schühle, Johannes

Highway Exhaust Emissions of a Natural Gas-Diesel Dual-Fuel Heavy-Duty Truck

2024-01-2120

04/09/2024

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, Shouvik, Qi, Aidu, Anderson, Andrew, Dahlseide, Austin, Smith, Brett, Lussier, Simon-Alexandre, Guo, Hongsheng, Rosenblatt, Deborah

Diesel Fuel-Fired Heater Emissions from a Battery Electric Transit Bus in Real-World Conditions

2024-01-5011

02/01/2024

Battery electric transit buses sold in Canada generally include a fuel-fired diesel auxiliary heater for cabin heating in cold weather. This report details a test project, performed in collaboration with OC Transpo, to capture and quantify the emissions from such a fuel-fired heater (FFH) installed on a New Flyer XE40 battery electric transit bus from OC Transpo’s fleet in Ottawa, Canada. The FFH was tested while the bus was both stationary and being driven on-road in cold conditions. The results include the emissions rates of carbon dioxide, carbon monoxide, nitrogen oxides, hydrocarbons and methane, and soot. Additionally, total particulate matter results were obtained during stationary testing. The results of stationary testing were compared to the California Air Resources Board and European Union standards for FFH emissions, even though these standards do not apply directly to buses operated outside of these jurisdictions. During stationary testing, average emissions of carbon

Humphries, Kieran, Rashid, Hussein, Araji, Fadi

Environmental and Cancer Risk Potential Assessment of Unregulated Emissions from Methanol-Diesel Dual Fuel RCCI Engine

2024-26-0152

01/16/2024

The influence of engine load and fuel premixing ratio (PMR) on unregulated emission from a methanol-diesel dual-fuel RCCI (MD-RCCI) engine is examined in this study. The study focuses on assessing the adverse effects of unregulated emissions (saturated HC, unsaturated HC, carbonyl compounds, aromatic hydrocarbon, NH3, and SO2) on the health of human beings and the environment. To quantify the effect on the environment, the greenhouse gas potential (GWPs), Eutrophication potential (EP), Acidification potential (AP), and Ozone forming potential (OFP) are calculated and presented. The cancer risk potential (CRP) of the carbonyl compounds (HCHO and CH3CHO) is calculated and presented to see the effect on human health. The results demonstrate that at lower engine load, with an increase in PMR, the OFP and CRP for MD-RCCI operation increase significantly, whereas AP, EP, and GWPs decrease. Additionally, with a rise in the load at a constant PMR, the AP, EP and OFP decrease significantly. The

Yadav, Neeraj Kumar, Saxena, Mohit Raj, Maurya, Rakesh Kumar

Oil Aerosol Emission Optimization Using Deflectors in Turbo Charger Oil Drain Circuit

2024-26-0047

01/16/2024

Closed crankcase ventilation prevent harmful gases from entering atmosphere thereby reducing hydrocarbon emissions. Ventilation system usually carries blowby gases along with oil mist generated from Engine to Air intake system. Major sources of blowby occurs from leak in combustion chamber through piston rings, leakage from turbocharger shafts & leakage from valve guides. Oil mist carried by these blowby gases gets separated using separation media before passing to Air Intake. Fleece separation media has high separation efficiency with lower pressure loss for oil aerosol particles having size above 10 microns. However, efficiency of fleece media drops drastically if size of aerosol particles are below 10 microns. Aerosol mist of lower particle size (>10 microns) generally forms due to flash boiling on piston under crown area and from shafts of turbo charger due to high speeds combined with elevated temperatures. High power density diesel engine is taken for our study. It produces

M, Velshankar, Dharan R, Bharani, Dhadse, Ashish, Permude, Ashok, Loganathan, Sekar

SAE TOMORROW TODAY: The Problem(s) with Replacing Fossil Fuels

1343001/10/2024

Don't miss 2023's most-watched episode of SAE Tomorrow Today! From geopolitical pressures to the shunning of fossil fuels, there is no question the current state of energy in the US and globally is a mess. One possible answer? An "all of the above" approach. For candid insight into this topic, we sat down with Mark P. Mills, senior fellow at the Manhattan Institute and a faculty fellow at Northwestern University's McCormick School of Engineering and Applied Science. Mark served in the White House Science Office under President Reagan and subsequently provided science and technology policy counsel to a variety of private-sector firms, the Department of Energy, and U.S. research laboratories. He began his career as an experimental physicist and development engineer in microprocessors and fiber optics. As part of this wide-ranging discussion, Mark shares his views on the need for hydrocarbon, the instability of the grid, energy's relationship to inflation, the US dependence on China, and

Hineman, Marcie

Add-On Device Makes Home Furnaces Cleaner and Safer

TBMG-49819

01/01/2024

Natural gas furnaces not only heat your home, they also produce a lot of pollution. Even modern high-efficiency condensing furnaces produce significant amounts of corrosive acidic condensation and unhealthy levels of nitrogen oxides, carbon monoxide, hydrocarbons, and methane. These emissions are typically vented into the atmosphere and end up polluting our soil, water, and air.

Performance Investigation of Direct Injection Diesel Engine Characteristics Fuelled with Ternary Blends and Additive as Ethanol

2023-28-0125

11/10/2023

This study aims to examine the effectiveness and environmental impact of using linseed and jatropha oil as biodiesels in combination with diesel. These oils were transformed through a process called trans-esterification, and three blends of ethanol, biodiesel, and diesel were prepared in E10-B20, E15-B20, and E20-B20 configurations. Ethanol was added to improve the combustion properties. The performance of these novel blends was tested in a computerized single-cylinder water-cooled diesel engine to measure brake power and emissions. It was found that the ternary biodiesel mixtures produced lower NOx and CO emissions than regular diesel fuel. In terms of performance, the E10-B20 blend reduced brake-specific fuel consumption and increased brake thermal efficiency by 6.1% to diesel. The E15-B20 blend showed a significant reduction of about 50% in unburnt hydrocarbons when compared to regular diesel at heavy load conditions. Additionally, the NOx value also decreased by 28.15% compared to

P, Selvan, Kandasamy, Sudalaiyandi, Dharmaraj, Jones Joseph Jebaraj

Experimental and Modeling Study of NH ₃ -SCR on a Hydrocarbon-Poisoned Cu-CHA Catalyst

2023-01-1659

10/31/2023

A urea-selective catalytic reduction (SCR) system is used for the reduction of NOx emitted from diesel engines. Although this SCR catalyst can reduce NOx over a wide temperature range, improvements in NOx conversion at relatively low temperatures, such as under cold-start or low-load engine conditions, are necessary. A close-coupled SCR (cc-SCR), which was set just after the engine exhaust manifold, was developed to address this issue. The temperature of the SCR catalyst increases rapidly owing to the higher exhaust temperatures, and NOx conversion is then enhanced under cold-start conditions. However, since the diesel oxidation catalyst is not installed before the SCR catalyst, hydrocarbon (HC) emissions pass directly through the SCR catalyst and poison it, leading to lower NOx conversion. Therefore, the mechanism of NOx conversion reduction on HC-poisoned SCR catalysts are required to be studied. In this study, the effects of HC poisoning on the NOx conversion of Cu-CHA catalysts

Tanaka, Kotaro, Dobashi, Ibuki, Sakaida, Satoshi, Konno, Mitsuru

Experimental Comparison of a Rotary Valvetrain on the Performance and Emissions of a Light Duty Spark Ignition Engine

2023-01-1613

10/31/2023

Rotary valve technology can provide increased flow area and higher discharge coefficients than conventional poppet valves for internal combustion engines. This increase in intake charging efficiency can improve the power density of four-stroke internal combustion engines, particularly at high engine speeds, where flow is choked through conventional poppet valves. In this work, the valvetrain of a light duty single cylinder spark ignition engine was replaced with a rotary valve train. The impact of this valvetrain conversion on performance and emissions was evaluated by comparing spark timing sweeps with lambda ranging from 0.8 to 1.1 at wide open throttle. The results indicated that the rotary valvetrain increased the amount of air trapped at intake valve closing and resulted in a significantly faster burn duration than the conventional valvetrain. Additionally, the spark to CA10 burn duration of the rotary valvetrain was highly sensitive to spark timing, which was not true of the

Gainey, Brian, Vaseleniuck, Darrick, Cordier, Dan, Garrett, Norman

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