Browse Topic: Cetane

Items (778)

Application of Sustainable Aviation Fuels in CI Aviation Engines: In-Flight Investigations

2025-01-0317To be published on 07/02/2025

To achieve a significant reduction in net CO₂ emissions in the aviation sector, sustainable aviation fuels (SAFs) are considered a key factor. Current research efforts are therefore focused on SAFs, which exhibit properties that differ from conventional kerosene, particularly in aspects critical to compression-ignition (CI) engines, such as cetane number, evaporation behavior or lubricity. These differences necessitate dedicated investigations to assess their suitability and performance in such engines. However, real operating conditions — such as intake air- and exhaust- pressure levels during flight — cannot be fully replicated on standard engine test benches. For this reason, real flight experiments were conducted to address these limitations. Notably, this work marks the first instance of in-flight testing of SAFs in CI aviation engines, constituting a significant milestone in this research area. In the course of these investigations, ASTM D7566 Annex A2-compliant HEFA

Kleissner, Florian, Reitmayr, Christian, Hofmann, Peter

numerical investigation into the combustion and emission characteristics of ammonia direct injection mechanism

2025-01-0241To be published on 06/16/2025

Ammonia is an attractive option because of its relatively low greenhouse gas (GHG) emissions, high energy density, competitive cost, and ubiquitous infrastructure for manufacturing, storage, and distribution. In this work, the optimum combustion characteristics are investigated to propose an efficient ammonia engine for future investigation. The effects of ammonia addition on diesel combustion characteristics were numerically investigated in a CI engine. The investigation was conducted by structured 3D CFD modeling to analyze the combustion characteristics. The validation of the boundary condition was compared to the designed experimental ammonia engine. The direct injection timing of 10o-50oBTDC and injection pressure 300-800 bar was proposed to identify the optimum autoignition characteristics. The equivalence ratios 1, 0.75, 0.5, and 0.25 were used in order to analyze the high cetane number characteristics and the air-fuel ratio.

setiawan, ardhika, Lim, Ocktaeck

Evaluation of Several Jet Fuels under Compression-ignition Operation on Thermal Efficiency, NOx, Particulate Matter, and Particle Size Distribution

2025-01-0244To be published on 06/16/2025

Alternative fuels such as Fischer-Tropsch Synthesized Paraffinic Kerosene (FT-SPK) and Catalytic Hydrothermal Conversion Jet (CHCJ) are among those important sustainable aviation fuels (SAFs) for future transportation. However, these alternative fuels often vary in their fuel characteristics, which depend on feedstock and fuel production processes. Therefore, a detailed analysis of combustion, emissions, and efficiency of these alternative fuels must be performed under controlled experiments to understand the impact of fuel properties and operating conditions. Using a single-cylinder research engine (SCRE), extensive operating conditions were performed to realize any difference in performance that can be fundamentally understood by fuel properties (e.g., cetane number, heat of combustion, and density) of these fuels in comparison with Jet-A. The experimental setup includes high-speed data acquisition for combustion analysis and gaseous and solid emissions benches for nitrogen oxides

Cung, Khanh, Miganakallu Narasimhamurthy, Niranjan, Khalek, Imad, Hansen, Greg

A Study on Cetane on Demand Technology Part 1 - Development of Fuel Reformer to Improve Fuel Ignitability

2025-01-8447

04/01/2025

The integration of low-octane gasoline with a compression ignition combustion system has been proposed as a strategy to reduce Well-to-Wheel CO2 emissions from automobiles using petroleum-based fuel. In the current situation where low-octane gasoline is not widely available in the market, onboard reforming of commercial gasoline to increase the cetane number (lower the octane number) allows for compression ignition combustion even with commercial gasoline. This requires “Cetane on Demand” technology, which enables compression ignition combustion with both commercial gasoline and low-octane gasoline. It is known that the ignition property of fuel is enhanced when the fuel is oxidized to generate hydroperoxides. Moreover, the use of N-hydroxyphthalimide (NHPI) as a catalyst promotes hydroperoxide generation at low temperatures. The objective of this study is to develop a device that enhances the ignition properties of gasoline through onboard fuel reforming. Initially, from the seven

Hashimoto, Kohtaro, Yamada, Yoshikazu, Matsuura, Katsuya, Kudo, Tomohide, Chishima, Hiroshi, Al-Taher, Maryam, Kalamaras, Christos, Albashrawi, Reem

Combustion and Emission Performance from the Use of Acid-Catalysed Butanol Alcoholysis Derived Advanced Biofuel Blends in a Compression Ignition Engine

2025-01-8445

04/01/2025

Low-carbon alternatives to diesel are needed to reduce the carbon intensity of the transport, agriculture, and off-grid power generation sectors, where compression ignition (CI) engines are commonly used. Acid-catalysed alcoholysis produces a potentially tailorable low-carbon advanced biofuel blend comprised of mixtures of an alkyl levulinate, a dialkyl ether, and the starting alcohol. In this study, model mixtures based on products expected from the use of n-butanol (butyl-based blends) as a starting alcohol, were blended with diesel and tested in a Yanmar L100V single-cylinder CI engine. Blends were formulated to meet the flash point, density, and kinematic viscosity limits of fuel standards for diesel, the 2022 version of BS 2869 (off-road). No changes to the engine set-up were made, hence testing the biofuel blends for their potential as “drop-in” fuels. Changes in engine performance and emissions were determined for a range of diesel/biofuel blends and compared to a pure diesel

Wiseman, Scott, Li, Hu, Tomlin, Alison S.

Impacts of Injection Pressure on Split-Injection Energy-Assisted Compression-Ignition Combustion of Low Cetane Number SAFs with a Gaussian-Shaped Ribbed Piston Bowl Design

2025-01-8350

04/01/2025

The impact of injection pressure on a split-injection energy-assisted compression-ignition (EACI) combustion strategy was studied in an optically accessible engine with a custom ribbed piston bowl design. Three injection pressures (600, 800, and 1000 bar) were investigated for three split-injection dwells (1.5, 2.0, and 2.5 ms) with a fixed second injection timing of -5.0 CAD. The Gaussian-shaped ribbed piston bowl design was employed to position hot combustion gases from the first injection near the centrally located injector to enable rapid ignition and mixing-controlled combustion of the second injection. At 600-bar injection pressure, as injection dwell was shortened, relocation of hot combustion gases near the injector became increasingly more difficult due to less available time for relocation and due to the higher in-cylinder densities at the start-of-injection (SOI) for the first injection. Increased injection pressure (800 and 1000 bar) improved the relocation of the first

Amezcua, Eri, Stafford, Jacob, Kim, Kenneth, Kweon, Chol-Bum, Rothamer, David

A Study on Cetane on Demand Technology Part 2: Gasoline Reforming and Ignitability Evaluation

2025-01-8444

04/01/2025

The integration of low-octane gasoline with a compression ignition combustion system has been proposed as a strategy to reduce Well-to-Wheel CO2 emissions from automobiles in petroleum-based fuel. However low-octane gasoline is not widely available in the market currently. Onboard reforming of commercial gasoline to increase the cetane number (lower the octane number) allows for compression ignition combustion even with commercial gasoline. To reform commercial gasoline, a reformer with a spiral structure reactor and mechanical stirring air introduction was designed and prototyped based on the results of toluene reforming tests (A Study on Cetane on Demand Technology Part 1: Development of fuel reformer to improve fuel ignitability). Using N-hydroxyphthalimide (NHPI)-supported ZSM-5 as a catalyst, commercial gasoline was reformed. As a result, 25.5 liters of reformed gasoline was obtained. The hydroperoxide concentration in the entirety of our reformulated gasoline was determined to be

Matsuura, Katsuya, Hashimoto, Kohtaro, Yamada, Yoshikazu, Al-Taher, Maryam, Kalamaras, Christos, Voice, Alexander, Bhadra, Kaustav

Comprehensive Investigation of Combustion Characteristics, Emissions, and Tribological Properties of Synthetic Kerosene (S8) in a CVCC and CRDI Research Engine

2025-01-8443

04/01/2025

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, Valentin, Willis, James, Norton, Coleman, Davis, Zachary, Graham, Tristan, Nobis, Austin

Control-Oriented Statistical Model of In-Cylinder Pressure, Combustion Phasing, and Torque for Compression-Ignition Engines Operating with Low Cetane Fuels

2025-01-8351

04/01/2025

Sustainable aviation fuels are becoming more widely available for current and future engine powered propulsion systems. However, the diversity of ignition behavior in these fuels poses a challenge to achieving robust, efficient operation. Specifically, low cetane fuels with poor ignitability exhibit highly variable torque production unless fuel is injected earlier during compression. The tradeoff is that earlier injection may cause dangerously high in-cylinder pressure rise rates. Novel models that can simulate these competing behaviors are needed so that appropriate strategies may be developed for controlling combustion at low cetane fueling conditions. This work builds upon a previously developed model that simulates asymmetric combustion phasing (CA50) distributions as a function of fuel cetane, fuel injection timing, and electrical power supplied to an in-cylinder thermal ignition assist device. An extension of the model is presented in which the phasing output is used to

Ahmed, Omar, Middleton, Robert, Stefanopoulou, Anna, Kim, Kenneth, Kweon, Chol-Bum

Diesel Engine Performance and Combustion Imaging Analysis of Gas-to-Liquid and Polyoxymethylene Dimethyl Ether Blended Fuels

04-18-02-0010

02/12/2025

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, Gen, Yuan, Haoyu, Yamamoto, Hiroya, Tanaka, Shusuke, Ogawa, Hideyuki

Experimental Study on Combustion and Emission Characteristics of a Two-Stroke Engine applying PODE/Methanol Blends Direct Injection

2025-01-7112

01/31/2025

In order to realize the Paris Agreement, which aims to strengthen the global response to climate change, conventional internal combustion engines (ICE) need to contribute to reducing carbon emissions and improving thermal efficiency. More importantly, in the face of energy shortages, it is urgent to search for sustainable fuels. Poly-oxymethylene dimethyl ethers (PODE) and methanol are both regard as important low-carbon, alternative fuels due to their high oxygen content. Using PODE can overcome the characteristics of methanol as a low-reactivity fuel with a low cetane number and poor ignition properties. In this study, the combustion and emission characteristics of PODE/methanol blends were investigated in a two-stroke direct injection engine. Firstly, the performance of the engine under pure PODE (P100) and PODE/methanol blends (P50) was compared. The results show that at BMEP of 0.31 MPa and injection timing of -8°CA ATDE, P50 blends have lower CO2, CO, NOX and THC emissions than

Dong, Pengbo, Sun, Zhuohan, Wang, Qingyang, Wang, Yang, Cui, Jingchen, Zhang, Zhenxian, Long, Wuqiang

Physicochemical Characterization and Potential Applications of Biodiesel Produced from Industrial Fish Waste

2024-01-5106

11/22/2024

Biofuels are gaining significant global attention as renewable and alternative energy sources, produced from various materials through different extraction methods and conversion processes. Food industry generates not only substantial organic waste, presenting economic and ecological challenges but also potential opportunities for valorization. This study focuses on recovering industrial fish waste from the manufacture of canned tuna, specifically targeting non-food and abundant fish co-products such as heads, bones, skin, and viscera, which constitute nearly 50% of the fish body. The process involves several steps: oil extraction using Soxhlet extraction, purification, and conversion into biodiesel via transesterification, followed by physicochemical analysis. The experiments revealed that 32.41% of fish waste was in the liquid phase (a mixture of hexane and oil), and the extracted oil accounted for 26.56% of the total fish waste weight (from 1.012 kg of waste, approximately 268.78 g

Bousbaa, Hamza, NAIMA, Khatir, Lamia, Medjahed, Benramdane, Mohammed, Balasubramanian, Dhinesh, Johnson, Anish Jafrin Thilak

Fuel Quality Assessment of Green Diesel Produced from Waste Cooking Oil

2024-01-4293

11/05/2024

Waste cooking oil can be converted into fuel for internal combustion (IC) engine applications by transesterification or pyrolysis. Transesterification results in the production of fatty acid methyl esters called biodiesel. The variability in biodiesel composition and properties from diesel fuel leads to engine re-calibration that requires significant time and effort. Diesel-like hydrocarbons can be produced by catalytic pyrolysis of used cooking oil. Such fuel can be used as a drop-in fuel in IC engine applications. Hydrogen at high pressures and a catalyst generally promote deoxygenation during pyrolysis. Recently, novel heterogenous acid catalysts such as Ni-impregnated activated carbon (AC) and Ag-Co-impregnated AC catalysts were developed to produce deoxygenated fuel by pyrolysis at atmospheric pressure without using hydrogen. Homogenous base catalysts such as sodium hydroxide can also be used in pyrolysis to produce diesel-like fuel. The present work compares the suitability of

Chellachamy, Adhikesavan, Krishnasamy, Anand

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

Operation of a Compression-Ignition Kerosene Aviation Engine with Sustainable Aviation Fuel: An Experimental Study

2024-01-6005

10/28/2024

The aviation industry is undergoing environmental scrutiny due to its significant greenhouse gas emissions. Sustainable aviation fuels (SAFs) are a vital solution for reducing carbon emissions and pollutants, aligning with global efforts for carbon-neutral aviation growth. SAFs can be produced via multiple production routes from different feedstock, resulting in significantly different physical and chemical fuel properties. Their suitability in a compression-ignition (CI) aircraft engine was evaluated through test bench investigations at TU Wien - Institute of Powertrain and Automotive Technology in partnership with Austro Engine. ASTM D7566-certified fuels like Hydrotreated Vegetable Oil (HVO), Fischer–Tropsch–Kerosene (FTK) or Alcohol to Jet (AtJ), but also an oxygen containing biodiesel have been tested extensively. Gaseous emissions, soot emissions, indication measurement data, efficiencies, and the like were acquired and comprehensively analyzed for engine operation with different

Kleissner, Florian, Hofmann, Peter

Numerical Investigations on Reducing Unburned Hydrocarbon and Carbon Monoxide Emissions in Reactivity-Controlled Compression Ignition Using Partial Reactivity Stratification with Alternative Fuels and Additive

03-18-01-0005

10/04/2024

A numerical investigation has been performed in the current work on reactivity-controlled compression ignition (RCCI), a low-temperature combustion (LTC) strategy that is beneficial for achieving lower oxides of nitrogen (NOx) and soot emission. A light-duty diesel engine was modified to run in RCCI mode. Experimental data were acquired using diesel as HRF (high-reactivity fuel) and gasoline as LRF (low reactivity fuel) to check the accuracy and fidelity of predicted results. Blends of ethanol and gasoline with DTBP (di-tert-butyl peroxide) addition in a small fraction on an energy basis were used in numerical simulations to promote ignitability and reactivity enhancement of PFI charge. Achieving stable, smooth, and gradual combustion in RCCI is challenging at low loads, especially in light-duty engines, due to misfiring and poor combustion stability. DTBP is known for enhancing cetane number and accelerating combustion, and it is mixed in a PFI blend to avoid combustion deterioration

Tripathi, Saurabh, Krishnasamy, Anand

Experimental Study of Lignin Fuels for CI Engines

2024-37-0022

06/12/2024

This study explores the feasibility of using a sustainable lignin-based fuel, consisting of 44 % lignin, 50 % ethanol, and 6 % water, in conventional compression ignition (CI) marine engines. Through experimental evaluations on a modified small-bore CI engine, we identified the primary challenges associated with lignin-based fuel, including engine startup and shutdown issues due to solvent evaporation and lignin solidification inside the fuel system, and deposit formation on cylinder walls leading to piston ring seizure. To address these issues, we developed a fuel switching system transitioning from lignin-based fuel to cleaning fuel with 85 vol% of acetone, 10 vol% of water and 5 vol% of ignition improving additive, effectively preventing system clogs. Additionally, optimizing injection parameters, adopting a constant pressure delivery valve, and fine-tuning injection timing mitigated lignin deposit formation related to incomplete combustion or spray tip penetration to the cylinder

Terauchi, Motoki, Simonsen, Tor, Mortensen, Simon, Schramm, Jesper, Ivarsson, Anders

Spectroscopy-Based Machine Learning Approach to Predict Engine Fuel Properties of Biodiesel

03-17-07-0051

04/11/2024

Various feedstocks can be employed for biodiesel production, leading to considerable variation in composition and engine fuel characteristics. Using biodiesels originating from diverse feedstocks introduces notable variations in engine characteristics. Therefore, it is imperative to scrutinize the composition and properties of biodiesel before deployment in engines, a task facilitated by predictive models. Additionally, the international commercialization of biodiesel fuel is contingent upon stringent regulations. The traditional experimental measurement of biodiesel properties is laborious and expensive, necessitating skilled personnel. Predictive models offer an alternative approach by estimating biodiesel properties without depending on experimental measurements. This research is centered on building models that correlate mid-infrared spectra of biodiesel and critical fuel properties, encompassing kinematic viscosity, cetane number, and calorific value. The novelty of this

Bukkarapu, Kiran Raj, Krishnasamy, Anand

Impact of a Split-Injection Strategy on Energy-Assisted Compression-Ignition Combustion with Low Cetane Number Sustainable Aviation Fuels

2024-01-2698

04/09/2024

The influence of a split-injection strategy on energy-assisted compression-ignition (EACI) combustion of low-cetane number sustainable aviation fuels was investigated in a single-cylinder direct-injection compression-ignition engine using a ceramic ignition assistant (IA). Two low-cetane number fuels were studied: a low-cetane number alcohol-to-jet (ATJ) sustainable aviation fuel (SAF) with a derived cetane number (DCN) of 17.4 and a binary blend of ATJ with F24 (Jet-A fuel with military additives, DCN 45.8) with a blend DCN of 25.9 (25 vol.% F24, 75 vol.% ATJ). A pilot injection mass sweep (3.5-7.0 mg) with constant total injection mass and an injection dwell sweep (1.5-3.0 ms) with fixed main injection timing was performed. Increasing pilot injection mass was found to reduce cycle-to-cycle combustion phasing variability by promoting a shorter and more repeatable combustion event for the main injection with a shorter ignition delay. For both fuels, dwells between 2.0 and 2.5 ms

Stafford, Jacob, Amezcua, Eri, Miganakallu Narasimhamurthy, Niranjan, Kim, Kenneth, Kweon, Chol-Bum, Rothamer, David

Development of Oxygenated Diesel Fuel and Impact on Vehicle Performance

2024-01-2374

04/09/2024

World is moving towards cleaner, greener and energy efficient fuels. The rapid increase in the consumption of petroleum fuel has led to twin problem of air pollution and energy security. India being a developing nation, fuel demand and consumption in various industries, especially in road transport sector has been rising continuously. Fossil fuels are the main source of energy and approximately 85% of domestic need met through import of crude oil. The increasing fuel consumption has created interest for the blending of biofuels in conventional fuel and renewable fuels also. Among biofuels ethanol is one of them and preferable choice for blending in gasoline which is a fuel for spark ignition engines and flex fuel vehicles. As such ethanol/methanol cannot be used in compression-ignition diesel engines without engine modifications due to inherent low cetane number and lubricity of alcohols. Therefore, fuel consisting of certain concentrations of alcohols such as methanol/ethanol in

Chakradhar, Maya, Chakrahari, Kiran K., Prakash, Shanti, Raj, Justin, Arora, Ajay, Maheshwari, Mukul, Harinarain, Ajay

Optical Diagnostic Study on Ammonia-Diesel and Ammonia-PODE Dual Fuel Engines

2024-01-2362

04/09/2024

Ammonia shows promise as an alternative fuel for internal combustion engines (ICEs) in reducing CO2 emissions due to its carbon-free nature and well-established infrastructure. However, certain drawbacks, such as the high ignition energy, the narrow flammability range, and the extremely low laminar flame speed, limit its widespread application. The dual fuel (DF) mode is an appealing approach to enhance ammonia combustion. The combustion characteristics of ammonia-diesel dual fuel mode and ammonia-PODE3 dual fuel mode were experimentally studied using a full-view optical engine and the high-speed photography method. The ammonia energy ratio (ERa) was varied from 40% to 60%, and the main injection energy ratio (ERInj1) and the main injection time (SOI1) were also varied in ammonia-PODE3 mode. The findings demonstrate that ammonia-PODE3 mode exhibits better ignition characteristics than ammonia-diesel mode, resulting in an earlier ignition start, a larger flame area, a larger flame

Mao, Jianshu, Zhang, Yixiao, Ma, Yue, Ma, Xiao, Wang, Zhi, Wang, Zhenqian, Shuai, Shijin

Innovative Catalysts for Biodiesel Generation from Edible Oils: Paving the Way for Cleaner Automobiles

2023-01-5125

02/23/2024

The study aims to produce biodiesel from waste cooking oil and compare the effects of two different catalysts (KOH and CaO) on the transesterification process. Homogeneous catalysts and heterogeneous catalysts are the two types of catalysts used in the transesterification process to produce biodiesel. In the present investigation, homogeneous catalysts KOH and heterogeneous catalyst CaO are used in the transesterification reaction. Catalysts are used to accelerate the reaction and increase reaction efficiency. The reaction temperature is set at 65°C. A methanol-to-waste cooking oil ratio of 6:1 is used for KOH and 8:1 for CaO. The catalyst amount is maintained at 2% of the weight of palmitic acid relative to the weight of waste cooking oil. The reaction time is 150 minutes for KOH and 240 minutes for CaO catalysts. The blends include B50C (50% biodiesel with CaO as catalyst and 50% conventional diesel fuel), B50K (50% biodiesel with KOH as catalyst and 50% conventional diesel fuel

Devan, P.K., Balasubramanian, M., Madhu, S., Prathap, P.

Use of Artificial Neural Network to Develop Surrogates for Hydrotreated Vegetable Oil with Experimental Validation in Ignition Quality Tester

04-17-02-0011

02/01/2024

This article presents surrogate mixtures that simulate the physical and chemical properties in the auto-ignition of hydrotreated vegetable oil (HVO). Experimental investigation was conducted in the Ignition Quality Tester (IQT) to validate the auto-ignition properties with respect to those of the target fuel. The surrogate development approach is assisted by artificial neural network (ANN) embedded in MATLAB optimization function. Aspen HYSYS is used to calculate the key physical and chemical properties of hundreds of mixtures of representative components, mainly alkanes—the dominant components of HVO, to train the learning algorithm. Binary and ternary mixtures are developed and validated in the IQT. The target properties include the derived cetane number (DCN), density, viscosity, surface tension, molecular weight, and volatility represented by the distillation curve. The developed surrogates match the target fuel in terms of ignition delay and DCN within 6% error range. This

Alkhayat, Samy, Joshi, Gaurav, Henein, Naeim

Effect of Diesel-Ethanol Blends on the Performance and Emissions of a CI Diesel Engine Suitable for Stationary Application

2024-26-0078

01/16/2024

Ethanol, being a bio-based alternate fuel, is one of the most promising fuels for blending with diesel for emissions reduction, primarily due to its oxygenated nature, which results in lower carbon content than diesel. Under this research work, various ethanol-diesel (ED) blends have been developed for investigation. Additives were developed to address the problem of corrosion, cetane number reduction, and blend stability. A detailed physico-chemical characterization was performed, and all the blends were subjected to the stability test at various temperatures. Subsequently, detailed experiments were conducted to understand ethanol- blended diesel fuels combustion and engine-out emission characteristics. The performance of the tested engine with ethanol blending remained at par with the baseline diesel; however, a reduction in the PM and gaseous emissions established ethanol blend as a favourable fuel solution for the tested CI engine. Experimental results indicate that blending

Garg, Rahul, Mukherjee, Nalini, Viswanath, Chithra, Choudhary, Vasu, Newalkar, Bharat, Nene, Devendra, Kusumba, Manoj

Impacts on combustion from the metal oxide nanoparticles use as an additive in biodiesel: literature review

2023-36-0119

01/08/2024

Although pure biodiesel is used in diesel engines, some challenges, such as higher density, lower cetane number, and lower calorific value, prevent it from completely replacing conventional fossil diesel. Therefore, the addition of compounds aimed at improving the biodiesel combustion process or improving its physicochemical properties is a fundamental issue in using them in pure form or in high proportions in engines, thereby maintaining the performance of such equipment. An alternative that has been studied in recent years is the addition of nanoparticles to biodiesel, which act as catalysts in the combustion process. This study examined in detail the influence of nanoadditives on the performance, combustion, and emissions characteristics of the CI engine. Furthermore, it will discuss the challenges and potential future directions in the utilization of nanoparticles to improve the use of biodiesel in CI engines. The reviewed articles show that the addition of nanoparticles to

Rosa, Josimar Souza, Smaniotto, Marcos Moresco, Telli, Giovani Dambros

Investigation of Performance of Fischer-Tropsch Coal-to-Liquid Fuel, IPK, in a Common Rail Direct Injection Compression Ignition Research Engine with Varying Injection Timing

2023-01-1643

10/31/2023

An investigation of the performance and emissions of a Fischer-Tropsch Coal-to-Liquid (CTL) Iso-Paraffinic Kerosene (IPK) was conducted using a CRDI compression ignition research engine with ULSD as a reference. Due to the low Derived Cetane Number (DCN), of IPK, an extended Ignition Delay (ID), and Combustion Delay (CD) were found for it, through experimentation in a Constant Volume Combustion Chamber (CVCC). Neat IPK was analyzed in a research engine at 4 bar Indicated Mean Effective Pressure (IMEP) at three injection timings: 15°, 20°, and 25° BTDC. Combustion phasing (CA50) was matched with ULSD at 10.8° and 16° BTDC. The IPK DCN was found to be 26, while the ULSD DCN was significantly higher at 47 in a PAC CID 510. In the engine, IPK’s DCN combined with its short physical ignition delay and long chemical ignition delay compared to ULSD, caused extended duration in Low Temperature Heat Release (LTHR) and cool flame formation. It was found in an analysis of the Apparent Heat Release

Soloiu, Valentin, Willis, James, Weaver, Amanda, O'Brien, Brandon, Dillon, Nicholas, Davis, Zachary

Designing High-Performance Fuels through Graph Neural Networks for Predicting Cetane Number of Multicomponent Surrogate Mixtures

2023-32-0052

09/29/2023

Cetane number (CN) is an important fuel property in designing high-performance fuels in recently diversifying compression ignition engines. We introduce graph neural networks (GNNs) that predict CNs of multicomponent surrogate mixtures when only 2D structures and mole fractions of molecules are given. It considers the influences of mixing multiple components and their chemical structures on CN, reproducing the non-linear blending behavior observed for certain mixtures. We trained the GNNs using the CNs of 1,143 mixtures, and reliable accuracy was achieved with mean absolute errors of 3.4-3.8 from the cross-validation. Lastly, we analyzed the chemical structural effects on non-linear blending behavior.

Kim, Yeonjoon, Kumar, Sabari, Cho, Jaeyoung, Naser, Nimal, Ko, Wonjong, St. John, Peter C., McCormick, Robert L., Kim, Seonah

Thermal efficiency improvement in twin shaped semi- premixed diesel combustion with a combustion chamber dividing fuel sprays and optimization of fuel ignitability

2023-32-0051

09/29/2023

The authors have reported significant smoke reduction in twin shaped semi-premixed diesel combustion with a newly designed combustion chamber to distribute the first and the second sprays into upper and lower layers. However, the first stage premixed combustion tends to advance far from the TDC, resulting in lowering of thermal efficiencies. In this report, improvement of thermal efficiency by optimizing the combustion phase with lower ignitability fuels was identified with the divided combustion chamber. The experiment was conducted with four fuels with different cetane numbers. The first stage premixed combustion can be retarded to the optimum phase with the fuel with cetane number 38, establishing high efficiencies.

Inaba, Kazuki, Kobashi, Yoshimitsu, Shibata, Gen, Ogawa, Hideyuki

Ignition and Combustion Controls of Synthetic Fuel using Diesel Engine with Variable Valve Timing System [First Report]

2023-32-0060

09/29/2023

Because the transportation industry uses fossil fuels as much as 1/4 of the total, CO2 emission from transport sector should be reduced. Therefore, carbon neutral (CN) fuel has been attracted attention. However, hydrogen and ammonia have low energy density and are difficult to be stored and transported. In this study, synfuel produced by Fischer-Tropsch (FT) reaction. This fuel is produced with carbon dioxide absorbed from the direct air capture and electricity derived from renewable energy, so it is possible to achieve CN. However, FT fuel tends to have less aromatics and a higher cetane number than diesel fuel. Therefore, excessive early ignition occurs at low speed and low load in application to diesel engine. The purpose of this study is to suppress early ignition by controlling the amount of air flowing into the cylinder. The numerical results showed that the ignition timing and combustion could be controlled using Miller cycle by late intake valve closing (LIVC). In addition, by

Sumida, Yo, Terada, Masaya, Kawano, Daisuke

On-Board Fuel Sensing for UAS and Ground Vehicle Applications

2024-01-4128

08/10/2023

The variability in fuel, particularly for fuel blends containing sustainable aviation fuels (SAFs), emphasizes the importance of understanding fuel properties for optimizing engine performance. This paper introduces spectroscopic fuel sensors capable of real-time estimation of jet fuel properties, mainly derived cetane number (DCN). While initially developed for unmanned aircraft systems (UAS), the paper explores their potential in ground vehicle applications: enhancing engine performance through sensing for feed-forward control and fuel property monitoring at fuel depots. The fuel sensing technologies are based on spectroscopic techniques coupled with machine learning (ML) approaches. The combination of these techniques demonstrates a promising solution for a wide spectrum of fuel applications.

Patel, Dev B., Sutar, Ashish, Abraham, Abhinav, Ambre, Dhananjay, Brezinsky, Kenneth, Lynch, Patrick T., Okada, Haruna, Stafford, Jacob M., Miganakallu, Niranjan, Sanders, Scott, Rothamer, David, Mayhew, Eric, Kim, Kenneth S.

Numerical Investigation of the Effects of Physical Properties on Spray Characteristics and NVH Characteristics

2023-01-1127

05/08/2023

For liquid fueled engine, the fuel atomization affects fuel’s evaporation, combustion, noise and vibration characteristics eventually. In this study, the effects of fuel species on the internal flow and near field primary breakup characteristics of a nozzle “Spray C” are investigated. Based on the framework of OpenFOAM, the newly developed solver which coupled cavitation model and the multifluid-quasi-VOF (Volume-of-Fluid) model, and combines the LES (Large Eddy Simulation) are applied to simulate the nozzle inner flow and near field jet breakup when using diesel and biodiesel respectively. The transient characteristics of nozzle inner flow and near field spray of two different fuels were analyzed, and the variation of axial pressure and velocity of nozzle was obtained. The simulation results show that the cavitation of biodiesel with high viscosity and low saturated vapor pressure develops slower and weaker. At the same time, due to the high viscosity of biodiesel, the flow velocity

Liu, Canxu, Dang, Yongjie, Xi, Xi, Zhang, Runqi, Li, Wenfei, Liu, Hong

Development of Data-Driven Models for the Prediction of Fuel Effects on Diesel Engine Performance and Emissions

04-16-03-0020

04/20/2023

A modelling tool has been developed for the prediction of fuel effects on the performance and exhaust emissions of a heavy-duty diesel engine. Recurrent neural network models with duty-cycle, engine control, and fuel property parameters as inputs were trained with transient test data from a 15-liter heavy-duty diesel engine equipped with a common-rail fuel injection system and a variable geometry turbocharger. The test fuels were formulated by blending market diesel fuels, refinery components, and biodiesel to provide variations in preselected fuel properties, namely, hydrogen-to-carbon (H/C) ratio, oxygen-to-carbon (O/C) ratio, derived cetane number (CN), viscosity, and mid- and end-point distillation parameters. Care was taken to ensure that the correlation between these fuel properties in the test fuel matrix was minimized to avoid confounding model input variables. The test engine was exercised over a wide variety of transient test cycles during which fuel rail pressure, injection

Schaberg, Paul, Harms, Thomas

Understanding Hydrocarbon Emissions to Improve the Performance of Catalyst-Heating Operation in a Medium-Duty Diesel Engine

2023-01-0262

04/11/2023

To cope with regulatory standards, minimizing tailpipe emissions with rapid catalyst light-off during cold-start is critical. This requires catalyst-heating operation with increased exhaust enthalpy, typically by using late post injections for retarded combustion and, therefore, increased exhaust temperature. However, retardability of post injection(s) is constrained by acceptable pollutant emissions such as unburned hydrocarbon (UHC). This study provides further insight into the mechanisms that control the formation of UHC under catalyst-heating operation in a medium-duty diesel engine, and based on the understanding, develops combustion strategies to simultaneously improve exhaust enthalpy and reduce harmful emissions. Experiments were performed with a full boiling-range diesel fuel (cetane number of 45) using an optimized five-injections strategy (2 pilots, 1 main, and 2 posts) as baseline condition. Time-resolved UHC measurements in the exhaust port with varying injection timings

Cho, Seokwon, Wu, Angela, Lopez Pintor, Dario

Engine and Emissions Performance of Renewable Diesel in a Heavy-Duty Diesel Engine: A Single-cylinder Engine Experiment

2023-01-0273

04/11/2023

As an alternative fuel, renewable diesel (RD) could improve the performance of conventional internal combustion engines (ICE) because of its difference in fuel properties. With almost no aromatic content in the fuel, RD produces less soot emissions than diesel. The higher cetane number (CN) of RD also promotes ignition of the fuel, which is critical, especially under low load, and low reactivity conditions. This study tested RD fuel in a heavy-duty single-cylinder engine (SCE) under compression-ignition (CI) operation. Test condition includes low and high load points with change in exhaust gas recirculation (EGR) and start of injection (SOI). Measurements and analysis are provided to study combustion and emissions, including particulate matters (PM) mass and particle number (PN). It was found that while the combustion of RD and diesel are very similar, PM and PN emissions of RD were reduced substantially compared to diesel. Indicated thermal efficiency or fuel consumption were also

Cung, Khanh, Buffaloe, Gina, Briggs, Thomas, Bitsis, Chris, Smith, Edward, Khalek, Imad, Michlberger, Alexander

Investigation of Premixed Fuel Composition and Pilot Reactivity Impact on Diesel Pilot Ignition in a Single-Cylinder Compression Ignition Engine

2023-01-0282

04/11/2023

This work experimentally investigates the impact of premixed fuel composition (methane/ethane, methane/propane, and methane/hydrogen mixtures having equivalent chemical energy) and pilot reactivity (cetane number) on diesel-pilot injection (DPI) combustion performance and emissions, with an emphasis on the pilot ignition delay (ID). To support the experimental pilot ignition delay trends, an analysis technique known as Mixing Line Concept (MLC) was adopted, where the cold diesel surrogate and hot premixed charge are envisioned to mix in a 0-D constant volume reactor to account for DPI mixture stratification. The results show that the dominant effect on pilot ignition is the pilot fuel cetane number, and that the premixed fuel composition plays a minor role. There is some indication of a physical effect on ignition for cases containing premixed hydrogen. The results also show that the HC and CO emissions for the methane/ethane and methane/propane mixtures decrease despite an increase in

Tyrewala, Daanish, Rothamer, David, Ghandhi, J.

Potential of Di-Ethyl Ether in Reducing Emissions from Heavy-Duty Tractors

2023-01-0285

04/11/2023

Considering the demand for sustainable transport, alternative fuels are a keen research topic for IC engine researchers. Among various alternative fuels being explored, Di-ethyl ether (DEE) is gaining popularity off-late for compression-ignition (CI) engines owing to its high cetane rating, oxygen presence in its molecular structure, and lower carbon content. This study explores the suitability of DEE blends in tractor engines. DEE blends [15% and 30% (v/v)] with diesel were compared with baseline diesel for combustion, and emission characterisation, keeping all parameters identical, including the fuel injection timings. Results were analysed for different engine loads at 1500 rpm. Delayed combustion was observed with DEE blends with diesel, possibly due to a higher cooling effect from DEE vaporisation and retarded dynamic fuel injection due to its higher compressibility. However, the DEE blend fuelled engine performance was comparable to baseline diesel. Considerable reductions in NOx

Kalwar, Ankur, Singh, Akhilendra, Agarwal, Avinash Kumar

Combined Impacts of Engine Speed and Fuel Reactivity on Energy-Assisted Compression-Ignition Operation with Sustainable Aviation Fuels

2023-01-0263

04/11/2023

The combined impacts of engine speed and fuel reactivity on energy-assisted compression-ignition (EACI) combustion using a commercial off-the-shelf (COTS) ceramic glow plug for low-load operation werexxz investigated. The COTS glow plug, used as the ignition assistant (IA), was overdriven beyond its conventional operation range. Engine speed was varied from 1200 RPM to 2100 RPM. Three fuel blends consisting of a jet-A fuel with military additives (F24) and a low cetane number alcohol-to-jet (ATJ) sustainable aviation fuel (SAF) were tested with cetane numbers (CN) of 25.9, 35.5, and 48.5. The ranges of engine speed and fuel cetane numbers studied are significantly larger than those in previous studies of EACI or glow-plug assisted combustion, and the simultaneous variation of engine speed and fuel reactivity are unique to this work. For each speed and fuel, a single-injection of fixed mass was used and the start of injection (SOI) was swept for each IA power. A maximum pressure rise

Stafford, Jacob, Amezcua, Eri, Miganakallu Narasimhamurthy, Niranjan, Kim, Kenneth, Kweon, Chol-Bum, Rothamer, David

Combustion Regimes in the Chrysler Multi-Air Multi-Fuel Engine, Part 2 - Diesel Micro-Pilot Combustion

2023-01-0222

04/11/2023

This paper is the second of three papers stemming from a dual fuel Chrysler prototype engine which uses both diesel and gasoline direct injection running at near-stoichiometric conditions, as part of a project to explore the viability of incorporating an engine platform which utilizes low temperature combustion regimes into a modern automotive application. The combustion system was designed to tolerate high rates of EGR while maintaining combustion stability by using high charge motion intake port and a high energy ignition system. The engine ran on highly dilute SI combustion at low loads, Diesel Assisted Spark Ignition at medium loads and a transition to Diesel Micro Pilot ignition at medium to high load. The first paper explored the use of Diesel Assisted Spark Ignited at moderate loads 6.5 bar to 12.7 bar BMEP and the third paper to be published in 2024 will explore fuel property effects (mainly Cetane and Octane) through the use of alternative fuels. This paper explores the use of

Church, William, McConnell, Steven

Combustion Characteristics of Low DCN Synthetic Aviation Fuel, IPK, in a High Compression Ignition Indirect Injection Research Engine

2023-01-0272

04/11/2023

The Coal-To-Liquid (CTL) synthetic aviation fuel, Iso-Paraffinic Kerosene (IPK), was studied for ignition delay, combustion delay, pressure trace, pressure rise rate, apparent heat release rate in an experimental single cylinder indirect injection (IDI) compression ignition engine and a constant volume combustion chamber (CVCC). Autoignition characteristics for neat IPK, neat Ultra-Low Sulfur Diesel (ULSD), and a blend of 50%IPK and 50% ULSD were determined in the CVCC and the effects of the autoignition quality of each fuel were determined also in an IDI engine. ULSD was found to have a Derived Cetane Number (DCN) of 47 for the batch used in this experimentation. IPK was found to have a DCN of 25.9 indicating that is has a lower affinity for autoignition, and the blend fell between the two at 37.5. Additionally, it was found that the ignition delay for IPK in the CVCC was 5.3 ms and ULSD was 3.56 ms. This increase in ignition delay allowed the accumulation of fuel in the combustion

Soloiu, Valentin, Weaver, Amanda, Smith, Richard, Rowell, Aidan, Mcafee, John, Willis, James

Exploration of Fuel Property Impacts on the Combustion of Late Post Injections Using Binary Blends and High-Reactivity Ether Bioblendstocks

2023-01-0264

04/11/2023

In this study, the impacts of fuel volatility and reactivity on combustion stability and emissions were studied in a light-duty single-cylinder research engine for a three-injection catalyst heating operation strategy with late post-injections. N-heptane and blends of farnesane/2,2,4,4,6,8,8-heptamethylnonane were used to study the impacts of volatility and reactivity. The effect of increased chemical reactivity was also analysed by comparing the baseline #2 diesel operation with a pure blend of mono-ether components (CN > 100) representative of potential high cetane oxygenated bioblendstocks and a 25 vol.% blend of the mono-ether blend and #2 diesel with a cetane number (CN) of 55. At constant reactivity, little to no variation in combustion performance was observed due to differences in volatility, whereas increased reactivity improved combustion stability and efficiency at late injection timings. Fuels with higher reactivity were found to reduce engine-out hydrocarbon and carbon

Subramanian, Srinath, Rothamer, David

Experimental Studies on the Use of Methanol-Butanol Blends in a Hot Surface Ignition Engine

2023-01-0316

04/11/2023

The property of methanol to surface ignite can be exploited to use it in a diesel engine even though its cetane number is very low. Poor lubricity of methanol is still an issue and special additives are needed in order to safeguard the injection system components. In this work a common rail three cylinder, turbocharged diesel engine was run in the glow plug based hot surface ignition mode under different injection strategies with methanol as the main fuel in a blend with n-butanol. n-Butanol was used mainly to enhance the viscosity and lubricity of the blend. The focus was on the effect of different injection strategies. Initially three blends with methanol to n-butanol mass ratios of 60:40, 70:30 and 80:20 were evaluated experimentally with single pulse fuel injection. Subsequently the selected blend of 70:30 was injected as two pulses (with almost equal mass shares) with the gap between them and their timing being varied. Finally the effect of mass share of the injection pulses was

Krishnan, R Anoop, Elango, Pradeev, Ramesh, A

Extension and Validation of a Constant Equivalence Ratio Multi-Zone Approach to DME Combustion in Vessels and CI Engines

2023-01-0193

04/11/2023

This work has the objective to present the extension of a novel quasi-dimensional model, developed to simulate the combustion process in diesel Compression Ignition (CI) engines, to describe this process when Dimethyl ether (DME) is used as fuel. DME is a promising fuel in heavy-duty CI engines application thanks to its high Cetane Number (CN), volatility, high reactivity, almost smokeless combustion, lower CO2 emission and the possibility to be produced with renewable energy sources. In this paper, a brief description of the thermodynamic model will be presented, with particular attention to the implementation of the Tabulated Kinetic Ignition (TKI) model, and how the various models interact to simulate the combustion process. The model has been validated against experimental data derived from constant-volume DME combustion, in this case the most important parameters analyzed and compared were the Ignition Delay (ID) and Flame Lift Off Length (FLOL). Following this first validation

Ballerini, Alberto, D'Errico, Gianluca, Onorati, Angelo, Tamborski, Matteo

Detailed Compositional Comparison of Hydrogenated Vegetable Oil with Several Diesel Fuels and Their Effects on Engine-Out Emissions

04-16-03-0015

12/08/2022

The Coordinating Research Council (CRC) is actively involved in developing and applying advanced analytical techniques to the chemical characterization of transportation fuels. This article complements a 2017 CRC project to quantify and compare the effects of a commercially available renewable diesel fuel (hydrotreated vegetable oil [HVO]) and an ultralow sulfur diesel (ULSD) fuel on engine-out gaseous and particulate matter (PM) emissions from a light-duty vehicle. Results showed that the combustion of HVO fuel had an advantage over ULSD in terms of lowering engine-out emissions (THC, CO, NOx, etc.). Furthermore, this advantage is strongly related to the fuel composition. This article summarizes the results of advanced and comprehensive analytical tests on the same ULSD and HVO fuels and attempts to connect some of the engine-out emissions results to fuel composition and specific chemical structures. A variety of test methods, generally unavailable in combination, were employed, such

Bays, J. Timothy, Gieleciak, Rafal, Viola, Michael B., Lewis, Russ P., Cort, John R., Campbell, Kristen B., Coffey, Gregory W., Linehan, John C., Kusinski, Matthew

Diesel-Range Fuel Property Effects on Medium-Duty Advanced Compression Ignition for Low-Load NO _X Reduction

04-16-01-0006

10/14/2022

A diesel premixed-charge compression ignition (PCCI) technique was used at low loads at which exhaust temperature makes urea-selective catalytic reduction (SCR) use for nitrogen oxides (NOx) reduction challenging. A fuels matrix to examine the effects of increasing fuel volatility, bio-blendstocks, and cetane number on PCCI was formulated using a near-constant 15% aromatic content. The results showed that PCCI could provide greater than 67% NOx emissions reductions at 1,200 RPM, 3.1 bar indicated mean effective pressure (IMEP), and 2.0 bar IMEP. The filter smoke number (FSN) could also be reduced relative to a conventional diesel combustion (CDC) baseline. The reductions in FSN were more moderate in the order of 40-50%, depending upon the fuel used, IMEP, and combustion phasing (CA50) timing. Hydrocarbon (HC) emissions could be held to a marginally lower level than CDC emissions at some CA50 conditions by using higher-volatility and higher cetane number fuels and could potentially be

Sluder, C. Scott, Curran, Scott J.

Evaluation of the Effect of Low-Carbon Fuel Blends’ Properties in a Light-Duty CI Engine

2022-01-1092

08/30/2022

De-fossilization is an increasingly important trend in the energy sector. In the transport sector the de-fossilization efforts have been centered in promoting the electrification of vehicles, nonetheless other pathways, like the use of carbon neutral or carbon-offsetting fuels under current vehicle fleets, are also worth considering. Low-carbon fuels (LCF) can be synthetized from sources that can take advantage of the carbon already present in the atmosphere (either by technologies like direct carbon capture or biological processes like photosynthesis in biofuels) and use energy from renewable sources for the necessary industrial processes. Although, LCFs can be compared to fossil fuels as energy sources for internal combustion engines, their composition is not the same and their properties can modify the engine combustion and emissions. This work evaluates the use of several diesel-like LCFs in a light duty compression ignition engine and correlates the fuel consumption, NOx, soot and

Garcia, Antonio, Monsalve-Serrano, Javier, Villalta, David, Guzmán Mendoza, María Gabriela, Gaillard, Patrick, Durrett, Russell, Vassallo, Alberto, Pesce, Francesco Concetto

Combustion and Emission Characteristics of Butanol-Diesel Blend (B15) Doped with Diethyl Ether, Diglyme and Ethyl Diglyme in a CRDI Diesel Engine

2022-01-1073

08/30/2022

Butanol is a potential alternative fuel for diesel in compression ignition (CI) engines. Many of the physico-chemical properties of butanol such as low carbon-to-hydrogen (C/H) ratio compared to diesel, higher heating value, lower heat of vaporization and suitable density-viscosity values compared to ethanol and methanol makes it suitable as an alternative fuel. However, poor cetane number and miscibility are the limitations associated with butanol. The use of fuel additives as ignition improver could be beneficial in overcoming the issues associated with alcohols. In this work, an experimental investigation in a twin-cylinder CI engine was carried out to assess the effect of doped cetane improving additives (Diethyl ether (DEE), Diglyme (DEGME) and Ethyl diglyme (DEGEE)) for diesel-butanol blend (B15). Cylinder pressure trace, heat release rate (HRR), location of maximum in-cylinder pressure (Pmax) and maximum rate of heat release (HRRmax), engine performance (brake thermal efficiency

Sahu, Tomesh Kumar, Shukla, Pravesh Chandra

Investigations of Ignition Delay Behavior in a CFR F5 Cetane Rating Engine and a Modern Heavy-Duty Diesel Engine

2022-01-0446

03/29/2022

The American Society for Testing and Materials (ASTM) D613 test method involves the use of a variable compression ratio CFR F5 engine to determine the cetane number of diesel fuels for use in compression ignition engines. The CFR F5 remains relatively unchanged since its conception, utilizing a swirl prechamber, mechanical jerk fuel pump, and a 10.3 MPa cracking pressure pintle nozzle mechanical injector. Recent efforts to improve the repeatability of the F5 engine involved the development of prototype engines equipped with electronic fuel injection (EFI) and upgraded high-speed instrumentation. These modifications have demonstrated the capability to improve the ASTM D613 precision limits by at least a factor of two. Parameterization of injection strategy has further optimized the test method, producing cycle-to-cycle variations of ignition delay analogous to modern day compression ignition engines. This study aims to expand on these improvements by identifying and quantifying

Zeman, Jared, Nielson, Kevin, Dempsey, Adam

Effect of Fuel Cetane Number on the Performance of Catalyst-Heating Operation in a Medium-duty Diesel Engine

2022-01-0483

03/29/2022

To comply with increasingly stringent pollutant emissions regulations, diesel engine operation in a catalyst-heating mode is critical to achieve rapid light-off of exhaust aftertreatment catalysts during the first minutes of cold starting. Current approaches to catalyst-heating operation typically involve one or more late post injections to retard combustion phasing and increase exhaust temperatures. The ability to retard post injection timing(s) while maintaining acceptable pollutant emissions levels is pivotal for improved catalyst-heating calibrations. Higher fuel cetane number has been reported to enable later post injections with increased exhaust heat and decreased pollutant emissions, but the mechanism is not well understood. The purpose of this experimental and numerical simulation study is to provide further insight into the ways in which fuel cetane number affects combustion and pollutant formation in a medium-duty diesel engine. Three full boiling-range diesel fuels with

Cho, Seokwon, Busch, Stephen, Wu, Angela, Lopez Pintor, Dario

Ignition Sensitivity Analysis for Energy-Assisted Compression-Ignition Operation on Jet Fuels with Varying Cetane Number

2022-01-0443

03/29/2022

Local deposition of thermal energy can be used to assist the combustion process of low cetane number (CN) fuels in compression-ignition engines, here termed energy-assisted compression ignition (EACI). In the current work, a commercial ceramic glow plug, operated beyond its conventional operation range, was used as the ignition assistant (IA) and sensitivity of fuel jet ignition to operation parameters was studied for two fuels using EACI in an optical engine. A design-of-experiments (DoE) study was devised to determine which engine parameters influenced the energy-assisted pilot injection ignition process the most. The DoE was constructed with four parameters: injection pressure, injected mass, injection timing, and ignition assistant temperature. The fuels used were F24 (Jet-A with military additives) with a cetane number of 48 and a cetane number 35 fuel mixture consisting of 60% F24 and 40% of an alcohol-to-jet fuel (ATJ), blended on a volumetric basis. Simultaneous OH

Amezcua, Eri R., Kim, Kenneth, Rothamer, David, Kweon, Chol-Bum

A Study of the Effect of Electronic Fuel Injection on the CFR F5 Cetane Rating Engine - Part II

2022-01-0448

03/29/2022

Over the past few decades, numerous studies have been performed to investigate how to improve the precision of the ASTM D613 Standard Test Method for Cetane Number of Diesel Fuel Oil. Many of these studies concluded that inconsistent combustion is the main contributing factor behind the lack of precision in the cetane number method, followed by shortcomings in the instrumentation used to measure ignition delay. This study is a continuation of recent work that investigated the benefits of installing a high-pressure common rail electronic fuel injection (EFI) system onto a CFR F5 cetane engine. The previous work presented baseline engine measurements that compared EFI against the original mechanical fuel injection system, along with computational fluid dynamics (CFD) simulations of the EFI injection and combustion processes. The previous work also indicated EFI makes it possible to improve the current ASTM D613 cetane test precision limits by at least a factor of two. This study presents

Nielson, Kevin, Zeman, Jared, Dempsey, Adam

Items per page:

1 – 50 of 778