Fueled Engine Research Articles

Statistical analysis of Mesua Ferrea seed oil biodiesel fueled diesel engine at variable injection timings using response surface methodology

The twin problems, fossil fuel crisis and the rise in pollution, have activated research in different sources of renewable energy. In this regard, Mesua Ferrea seed oil biodiesel can be a solution which can be employed in diesel engines for power generation and transportation. Keeping this in view, Mesua Ferrea seed oil biodiesel is used in a diesel engine in this investigation. The potential for improvement in performance with varying engine load settings and injection timings is presented in this paper. The statistical investigation was carried out using analysis of variance [ANOVA], response surface methodology [RSM], and desirability-based optimization. A research test engine with a maximum load capacity of 3.5 kW was used for experimentation. Five load settings of engine [20 %, 40 %, 60 %, 80 %, 100 %] and four injection timings [20° BTDC, 23° BTDC, 25° BTDC, 28° BTDC] were employed for the study. Observation of results exhibited that the retarded injection timing of 20° BTDC lowers the emissions and improves the conversion efficiency of fuel for diesel engines powered with Mesua Ferrea seed oil biodiesel. The RSM-based modeling and optimization contributed to the identification of 23.45 % BTE, 49.75 PCP, 25.62 ppm CO, 1.38 % CO2, and 23.38 ppm HC at 20° BTDC FIT and 72.87 % engine load. The RSM-based model forecasted results were examined using a validation test, and the findings were well within 5 % of the model-predicted outcomes, suggesting a robust model.

Preliminary assessment of the potential for rapid combustion of pure ammonia in engine cylinders using the multiple spark ignition strategy

In pursuit of carbon neutrality, the adoption of zero-carbon fuels in internal combustion engines offers a path to zero carbon emissions. Among such fuels, ammonia (NH3) stands out as an effective hydrogen energy carrier with a higher energy density and a more advanced production-storage-transportation lifecycle than hydrogen (H2) fuel, making it a superior alternative. Nevertheless, achieving high combustion efficiencies in engine cylinders requires the use of fuels with fast flame speeds, since the time scales of the combustion event are practically milliseconds. The inherent flame speed of NH3 falls short, typically necessitating augmentation with H2. Yet, the in-situ generation of H2 from NH3 remains constrained, rendering the flame speed of NH3 less competitive against traditional fuels like gasoline and natural gas. To address the dual challenges of slow flame speed of NH3 and the difficulty of generating large amounts of H2 from NH3 onboard, this study evaluates an alternative method of accelerating the ammonia combustion in the engine combustion chamber through the use of multiple spark plugs, which is limited discussed in existing research. Numerical simulations performed in this study show that the application of the multi-spark strategy increases the mass burn rate, advances the combustion phasing, shortens the combustion duration, increases the engine power output, improves the fuel economy, and reduces the unburned ammonia emissions, all of which indicate that rapid combustion of pure ammonia is achieved in the combustion chamber. Moreover, the use of multiple spark points does not lead to a marked increase in nitrogen oxides emissions, thereby ensuring no added stress on exhaust aftertreatment systems. In addition, pure ammonia combustion appears to be very well adapted to this strategy, as evidenced by the avoidance of excessive cylinder pressures and pressure rise rates—a challenge faced by conventional spark ignition engines, given ammonia notably slower flame speed relative to conventional petroleum-based fuels. Overall, all these findings strongly support that the multi-spark ignition system presents a compelling direction for future zero-carbon ammonia engines. However, it is crucial to address design challenges to ensure that the engine head layout provides sufficient cooling, structural robustness, optimal breathing efficiency, and reliable multi-ignition events within the confined space.

Energy, exergy, sustainability evaluation of the usage of pyrolytic oil and conventional fuels in diesel engines

Solid wastes like used tires have high annual production and significant environmental impact potential. Tire wastes can be pyrolyzed to regenerate energy and create useful products. The purpose of this study is to demonstrate the use of pyrolytic oil produced by the pyrolysis of waste tires as fuel in diesel engines. The energy exergy and sustainability of pyrolytic oil and conventional marine diesel fuels were examined in this study. The energy was determined in the experimental processes used to transform used tires into carbon black, pyrolytic oil, and pyrolytic gas. The components of SOX, NOX, and CO2 produced when pyrolytic oil and conventional marine fuels were combusted in diesel engines were obtained. As a result of the study, the energy value of the pyrolytic oil produced during the pyrolysis process as fuel was determined to be 2.8 MW. The results indicated that the combustion of pyrolytic oil in diesel engines had a thermal efficiency of 38% and a second-law efficiency of 58%. The standard marine fuels were found to have a sustainability index of 2.7, while pyrolytic oil had a sustainability index of 1.42.

Thermodynamic analysis of a high Mach number scramjet engine with secondary combustion for thrust enhancement

Intending to augment the thrust of air-breathing vehicles operating at high flight Mach numbers, especially under extreme flight conditions, this study introduced a pioneering methodology predicated on secondary combustion. This innovative scheme uses the product of combustion of hydrocarbon fuel and air to further react with metal fuel to obtain thrust gain. This study was mainly based on theoretical calculation. A preliminary parametric design and performance analysis of a Mach 8 scramjet engine with an afterburner was carried out based on the thermodynamic cycle analysis method, considering the gas component changes. The engine model design with an inward two-dimensional inlet was adopted, along with an oblique injection of hydrocarbon fuel and two combustors in series. In addition, the expansion of gas in a supersonic nozzle was modeled with quasi-one-dimensional flow equations. By maintaining an equivalence ratio of 1.0 for the hydrocarbon fuel in the primary combustor, meticulous exploration of the powder-to-gas ratio in the afterburner, ranging from 0.04 to 0.2, was conducted. Similarly, an investigation into the temperature ratio at the outlet of the inlet, spanning the range of 3.8 to 7, was performed. Through a judicious optimization process involving both the inlet compression temperature ratio and the magnesium powder's powder-to-gas ratio, the engine designed can obtain a maximum thrust gain of 57.3%. The analysis underscores the advantageous correlation between heightened powder-to-gas ratios and augmented thrust production. Setting the upper limit of the powder-gas ratio to 0.16 is recommended to maintain optimal performance. This research also provided a new idea for expanding the application of hydrocarbon fuels in higher flight Mach number scramjet engines.

Visualization study on the ignition and diffusion combustion process of liquid phase ammonia spray ignited by diesel jet in a constant volume vessel

Ammonia fueled engines applying diffusion combustion mode is expected to further improve the thermal and combustion efficiencies with high burning rate and high ammonia energy replacement. However, there is a lack of the fundamental studies about ammonia diffusion combustion characteristics. Therefore, the fundamental optical experiments of liquid phase ammonia spray and combustion, which is ignited by pilot diesel injection, were performed to investigate the ignition and diffusion combustion characteristics of liquid phase ammonia. According to the high-speed photography, interaction processes between the liquid phase ammonia spray and the diesel spray had been described, and the whole ignition and combustion processes were also recorded in detail. The discussion about the effect of diesel jet ignition location on ammonia ignition process shows that the effective ammonia ignition zone by diesel spray is the region of gas entrainment zone except for the liquid phase ammonia volume under evaporated condition, where the interval on ammonia spray axis is about 16 mm ∼ 35 mm away from the ammonia nozzle exit under the current experimental conditions, and the ammonia spray is failed to be ignited at any region out of the effective ignition zone. Moreover, the ammonia diffusion combustion characteristics under various ammonia injection durations reveals that the entrainment, including both the diesel flame and the surrounding ambient gas, into the effective ignition zone of liquid phase ammonia spray, is the effective way to achieve reliable ignition and the subsequent diffusion combustion of ammonia, which can increase the energy ratio (ammonia to pilot diesel) up to at least 2.9. Finally, based on the control of combustion mode of the pilot diesel, utilizing premixed diesel flame to induce the diffusion combustion of ammonia is proved to be an effective regulation scheme to enhance the performance of ammonia combustion under engine-like thermal conditions.

Effect of Norozak (Salvia lerrifolia) biodiesel fuel on diesel engine performance

Most energy is produced from fossil fuels, and the use of these fuels has increased over the past years. Fossil fuels are the main cause of global pollution and global warming. Using vegetable oils as alternative fuels for diesel engines is one of the ways to reduce pollutant emissions. Biodiesel from Norozak (Salvia lerrifolia) oil has been produced using a transesterification process. Biodiesel is mixed with diesel oil in different proportions B05, B10, B15, and B20. Biodiesel's physical and chemical properties are measured according to ASTM standards. A single-cylinder diesel engine is employed as the test engine in the present work. The torque, power, Special Fuel Consumption (SFC), and Exhaust Gas Temperature (EGT) are measured and compared with diesel oil. Torque, power, and EGT are larger, and SFC is lower for biodiesel mixture B05 than diesel fuel.

Biomimetic swirl device and hydrogen enrichment effects on LPG fueled engine

Inspired by the humpback-whale flipper which enables robust aerodynamic force production, we propose a biomimetic blade design for small Biomimetic Swirl Device (BSD) added on gaseous engine inlet system. Such system can achieve robustness in aerodynamic performance for the intake flow. Therefore, the BSD design has an important impact on swirl generation inside the engine cylinder which its geometry was defined by a wavelength, leading edge radius and amplitude. For this reason, a numerical analysis method, by means a computational fluid dynamics 3D modeling technique, was utilized to study the in-cylinder flow characteristics investigating the optimal BSD geometry. Moreover, the effect of Hydrogen on in-cylinder flow characteristics of liquefied petroleum gas (LPG) bi-fuel engine has been examined using the BSD. In this research, five designs of the BSD with the dimensionless amplitude A* varied at 0.08, 0.12, 0.16, 0.2 and 0.24 were compared with the model without BSD to investigate its effect on the air-LPG flow inside the combustion chamber. The results showed that the BSD with A* = 0.2 created more turbulence, in-cylinder velocity, swirl in the combustion chamber than the other designs. Simulation results indicated also that LPG-30% H2 blend with BSD added gives the optimal in-cylinder flow characteristics of the TKE, the velocity and the swirl ratio.

Impact of Carbon Nanotubes and Graphene Oxide Nanomaterials on the Performance and Emissions of Diesel Engine Fueled with Diesel/Biodiesel Blend

Biodiesel produced from waste cooked oil (WCO) resources mixed with various nanoparticle additives and used as a fuel blend in diesel engine combustion is a hopeful research trend. All previous studies indicate that alternative fuels can provide better fuel properties with enhanced engine combustion, performance, and lower emissions than fossil diesel fuel. This study uses three fuel blends to compare the diesel engine’s combustion, performance, and emissions attributes at different loading values. Pure diesel fuel, B40, which is a blend of 40% WCO biodiesel and 60% diesel fuel, and mixtures of 40% WCO biodiesel, 56% diesel, and 4% toluene with carbon nanotubes (B40-CNTs) or graphene oxide nano-additive (B40-GO) at three concentrations of 50, 100, and 150 ppm were used. The results show enhancements in the diesel engine attribute values using B40-CNTs and B40-GO blends at different concentrations and engine load values better than the diesel engine attribute result values using B0 or B40 without nanoparticle additives. The combustion, performance, and emission attribute showed improvements using nanoparticles due to the increase in the evaporation rate, the oxygen rate, the surface area to volume ratio, and the thermal properties of the mixture. The highest in-cylinder peak pressure is recorded at 61 bar in B40 with 150 PPM of GO nanoparticles. The brake thermal efficiency records 43.6%, with the highest percentage found using B40-150GO at the maximum engine load value. The NOx emissions are dropped from 1240 PPM using pure diesel fuel to 884 PPM using B40 with 150 PPM of GO nanoparticles at the maximum engine load due to the lower combustion temperatures and duration.

Numerical Prediction on In-Cylinder Mixture Formation and Combustion Characteristics for SIDI Engine Fueled with Hydrogen: Effect of Injection Angle and Equivalence Ratio

Although their ease of transport, storage, and use makes hydrocarbon fuels dominant in commercial energy systems, the emission of harmful gases, including greenhouse gases, is a fatal disadvantage. Despite ongoing research to improve thermal efficiency and reduce the emissions of internal combustion engines using conventional hydrocarbon fuels, achieving net-zero carbon requires decarbonizing fuels rather than reducing the use of internal combustion engines. Hence, transitioning away from hydrocarbon fuels and evolving internal combustion engines into clean engines using carbon-free fuels, such as hydrogen, is necessary. This study designs a 2.0 L research engine and numerically analyzes its combustion characteristics and spray behavior by varying the spray angle and equivalence ratio. When comparing the turbulence kinetic energy at a 45-degree spray angle with that at 30 degrees and 60 degrees, on average, there was a difference of approximately 37.54 m2/s2 and 26.21 m2/s2, respectively. However, misfires occur in the lean condition. Although hydrogen has a wide flammability range, poor mixture formation under lean conditions can result in misfires. The 60-degree spray angle resulted in the highest combustion temperatures and pressures for all equivalence ratio conditions, consequently leading to the highest emissions of nitrogen oxides. Specifically, at a lambda value of 2.5, the 60-degree spray angle emitted approximately 29 ppm, 0 ppm, and 161 ppm of nitrogen oxides for each respective spray angle.

SYSTEMATIC INFORMATION BASE OF ENERGY-EFFICIENT APPLICATIONS FOR AVIATION PETROL

The additives in petrol was started to use in the first half of the twentieth century. In the late 1970s, a qualitative conceptual change in the development of this area of science and practice took place. Environmental pollution from harmful emissions led to the modification of petrol formulations and structural improvements of engines. The problem of improving the quality of gasoline and fuels for jet engines is usually solved in two ways: by developing high-quality new products and by efficient use of traditional ones.
 The proposed work analyses the scientific literature on energy-efficient additives to aviation gasoline and, on this basis, creates a systematic information base, namely: classification of the range of additives to gasoline (by the following features: chemical, physical and biological stability enhancers; flash point modifiers; combustion modifiers; washing; dopes that promote efficient operation of fuels at low temperatures; friction modifiers; marking agents; anti-corrosion agents; safety enhancers; surface-active property modifiers) and the range of anti-detonation and environmental (anti-emission) additives in aviation petrols.
 The following additives are manufactured and approved for use in Ukraine: poly-functional additives representing a complex mixture of manganese compounds and mixtures of paraffinic and naphthenic hydrocarbons (TU 30218597.001[in Ukrainian] "Poly-functional additives "Eco-Octane". Technical specifications"); iron-containing multifunctional additives "Standard"; there are also known developments of oxygenates based on methanol, ethanol and other alcohols, alcohol processing products, ethers and other oxygen-containing compounds.
 The research is being carried out within the framework of the project "Development of a technology for the production of new environmentally friendly high-octane aviation gasoline from domestic raw materials" at the expense of the state budget in accordance with the Order of the Cabinet of Ministers of Ukraine of 12 August 2022 No. 713-r "Pro zatverdzhennia pereliku naukovo-tekhnichnykh (eksperymentalnykh) rozrobok v ramkakh vykonannia derzhavnoho zamovlennia na naivazhlyvishi naukovo-tekhnichni (eksperymentalni) rozrobky ta naukovo-tekhnichnu produktsiiu u 2022 rotsi" [in Ukrainian] (registration number 2020.01/0242).

A Review of Isobutanol as a Fuel for Internal Combustion Engines

Isobutanol, one of the four isomers of butanol (C4H9OH), possesses some favorable properties that make it an attractive fuel for internal combustion engines. For instance, when compared to ethanol, isobutanol features a higher heating value and lower hygroscopicity (which prevents corrosion and enables it to be transported via pipelines). Moreover, its addition to gasoline does not distort the fuel blend’s vapor pressure to the same extent as ethanol does. All of this while having a high octane rating. Those advantages over ethanol suggest that isobutanol has the potential to be used as a gasoline oxygenate or even as a neat fuel. Furthermore, the advances made in biotechnology have enabled isobutanol to be produced from biomass more efficiently, allowing it to be used in compliance with existing renewable energy mandates. This article reviews some of the relevant literature dedicated to isobutanol as a motor fuel, covering its merits and drawbacks. Several studies on its combustion characteristics are also discussed. Most of the included literature refers to the use of isobutanol in spark-ignition (SI) engines, as its properties naturally lend themselves to such applications. However, isobutanol’s utilization in diesel engines is also addressed, along with a couple of low-temperature combustion examples.

A sustainable model using RSM and MCDM techniques to evaluate performance and emission characteristics of a diesel engine fueled with diphenylamine antioxidant and CeO2 nanoparticle additive biodiesel blends

Overconsuming fossil fuels has worsened global warming and air pollution, requiring us to investigate alternate fuels for compression ignition engines. Biodiesel is a renewable fuel and environmentally favorable. Biodiesel's most significant disadvantage is increased nitrogen oxide (NOx) emissions. The intent of the present study was to examine the impact of antioxidant diphenylamine (DPA) and nanoparticle ceria (CeO2) additive inclusion in a B30 blend on engine performance and exhaust emission characteristics. For this study, diesel, Jatropha biodiesel (B30), 100 ppm of antioxidant diphenylamine (50 ppm) with ceria nanoparticle (50 ppm) is added to the B30 blend named as B30+DPA100 and antioxidant diphenylamine (50 ppm) with ceria nanoparticle (50 ppm) is added to the B30 blend named as B30+DPA50+CeO250 fuel blends has been used. A hybrid response surface methodology and multi-criteria decision-making techniques (entropy method, TOPSIS, and VIKOR) have been used to develop a sustainable model and find the optimal setting of input parameters in terms of ranking. From experimental findings, the inclusion of antioxidants (DPA) and nanoparticle (CeO2) at 50 ppm to B30 significantly reduced NOx emission. The brake-specific fuel consumption and NOx have been found reduced by 5.67% and 18.87%, respectively, for B30+DPA50+CeO250 as compared to B30. At the same time, brake thermal efficiency increased by 1.01%. The brake mean effective pressure and maximum cylinder pressure) have been found increased by 0.68% and reduced by 4.52%, respectively, for B30+DPA50+CeO250 as compared to B30. The alternative ranking of the input parameters has been found fuel injection pressure (300), compression ratio (17), and load (12) as Rank 1 for TOPSIS and VIKOR. Therefore, the B30+DPA50+CeO250 blend is appropriate for improving diesel engine performance and diminishing exhaust emissions.

Numerical investigation for enhancing HCCI combustion characteristics in DI-CI engine fueled with butanol/diesel blends

The fast depletion of fossil fuels and the hazardous emissions associated with the use of fossil fuels in IC engines is driving the research in the area of renewable fuels. Homogeneous charge combustion ignition (HCCI) is a new mode of engine combustion technology, used for reducing the emissions without compromising the engine performance. The combination of HCCI and alcohol/diesel blends has the potential to simultaneously address the twin problems of depletion of fossil fuels and engine emissions. Butanol is an attractive biofuel, which is produced from agriculture wastes such as sugar cane bagasses and corn stalk etc. This paper presents numerical and modeling analysis on the emission and performance characteristics of a direct injection- compression ignition (DI-CI) engine operated with butanol/diesel blends. Numerical analysis was carried out using CONVERGE CFD software. Response surface methodology (RSM) was used in developing the response models for three output parameters, viz., nitrogen oxides (NOx), soot emissions and indicated specific fuel consumption (ISFC), in terms of the four input parameters, viz., compression ratio (CR), start of injection (SOI), fuel injection pressure (FIP) and exhaust gas recirculation (EGR). Numerical experiments were conducted by varying these four input parameters, i.e., CR from 14 to 19, FIP from 200 to 280 bar, EGR from 0% to 30% and SOI from 17° to 29° CA bTDC, and with four butanol/diesel blends (0, 20%, 30% and 40% of butanol-by volume, designated as Bu00, Bu20, Bu30 and Bu40). The optimum combination of the input parameters for the four test fuels were found with the objective of minimizing the three output parameters (i.e., ISFC, soot and NOx) using desirability approach. The homogeneity of the air-fuel mixture was estimated using equivalence ratio distribution index, i.e., Target fuel distribution index (TFDI). From the numerical analysis, it was found that the TFDI improved for the optimized case by 20.5%, 21.5%, 24.4% and 27.2% for Bu00, Bu20, Bu30 and Bu40 respectively as compared to their respective baseline configuration.

Artificial Neural Network based prediction of Specific Fuel Consumption in various Compression Ratio CI Engine Fueled with Various Plastic Composition Pyrolysis oil and Diesel

This study looks at the usage of Artificial Neural Network Modeling for predicting Specific Fuel Consumption for compression ignition engines running on Diesel, Low-Density Polyethylene Pyrolysis Oil (LDPE PO), High-Density Polyethylene Pyrolysis Oil (HDPE PO), and Polypropylene Pyrolysis Oil (PP PO). Using preliminary practical findings, The Model of ANN was built to estimate SFC by adjusting the parameters of the engine. SFC is anticipated by adjusting the parameters and utilizing the orthogonal array. The experiment is then carried out using an orthogonal array. The outcomes of experimental work are used to create an ANN model. In the case of a non-linear mapping between input & output, the classic back-propagation method and a multi-layer perception network are utilized. The values of Mean Square Error (MSE), Root Mean Square Error (RMSE), and Regression Coefficient (R2) for LM10TP architecture are 1.5143×10–06, 0.0012 & 1 in training & the validation values 1.2185×10–06, 0.0011 and 0.9999 respectively. It was discovered that neural networks are useful tools for prediction since they performed well in specific fuel consumption prediction in both training and validation.

Characteristics of ammonia premixture combustion ignited by a gasoline ignition chamber

Ammonia is a kind of clean and renewable fuel with great potential for engine applications. Since ammonia has low reaction characteristics, the addition of auxiliary fuels or special ignition techniques are required to enhance its combustion performance. In this study, a kind of ammonia combustion enhancement method was investigated, and the combustion process of ammonia, which was ignited by an ignition chamber with gasoline injection, was analyzed by visualization experiments. The experiments showed that using gasoline as ignition chamber fuel substantially reduced the ignition delay and the duration of ammonia combustion was reduced by 46.4% compared to the spark ignition mode. However, at the gasoline energy percentages of 1.0%, 1.5%, 2.0% and 2.5%, the ammonia combustion duration and peak pressure were proportional to gasoline energy. The combustion duration and high peak pressure could be balanced at the percentage of 1.5%. On the other hand, the geometrical effect of the outlet between the ignition chamber and the main chamber was also discussed. In comparison to the outlet diameters of 6.0 mm and 4.5 mm conditions, the jet flow development speed was faster under the 3.0 mm condition and it has the shortest combustion duration of 39.2 ms. Moreover, the fundamental experimental results indicated that the ignition chamber with gasoline had great potential in dealing with the equivalence ratio of 0.8, 1.0 and 1.1, which were detrimental to the combustion process of ammonia. Due to poor ignition at 1.0% gasoline energy percentage condition during lean combustion, resulting in poor performance of peak pressure and combustion duration, the 1.5% one was regarded to be more suitable within wide range of engine operations. Therefore, the results are expected to provide theoretical foundation for organizing and controlling the combustion of ammonia fueled engines.

Combustion and detonation of paste fuel of rocket engine

Purpose. Confirmation of the possibility of using a paste fuel based on ammonium perchlorate in a rocket engine and identifying the characteristics of its combustion. Methodology. Previous experimental studies on the burning of paste fuel in a constant pressure bomb determined the burning rate at different pressures. The stability of deflagration combustion without transition to the detonation mode was confirmed. An explosion occurred during the fire test of the engine model on paste-like fuel. The analysis of the causes of the explosion made it possible to put forward a hypothesis about the enrichment of the paste fuel with ammonium perchlorate, which created the prerequisites for its detonation. The conducted additional experiments showed a change in the combustion mode when enriching paste fuel with ammonium perchlorate. Findings. Theoretical and experimental studies have shown the possibility of obtaining detonation fuel based on the enrichment of paste fuel with ammonium perchlorate. It has been proven that, under certain production conditions, paste fuels can detonate, which opens up a new way of using such fuels for rocket engines. The conditions for the transition of the burning mode of pasty fuel from deflagration to detonation combustion are determined. The speed of the engine element during the explosion was evaluated and it was shown that during explosive combustion due to the large area and, accordingly, the mass flow, it is not possible to obtain a pressure value that could ensure the movement parameters registered in this engine design. Originality. Another criterion is established of engine operability when designing an engine on paste fuel. The effect of enrichment of pasty fuel with ammonium perchlorate during its flow through the supply system at the time of start-up was revealed. Practical value. The given information makes it possible to improve the design of the engine on paste fuel and to modernize the stand for its tests.

Experimental Investigation on the Effect of Graphene Oxide in Higher Alcohol Blends and Optimization of Injection Timing Using an ANN Method.

The use of alternative fuels in diesel engines has become more widespread due to a number of factors, including dwindling petroleum supplies, increasing prices for conventional fossil fuels, and environmental worries about pollutants and greenhouse gas emissions from internal combustion engines. Efficiency and emissions need to be appropriately balanced. Alcohols act as oxygenated fuels similar to octanol, offering a number of benefits over traditional fuels and can boost efficiency, enhance combustion, and reduce air pollution. Therefore, the research aimed to enhance the performance and combustion characteristics of a diesel and octanol blend using graphene oxide (GO) nanoparticles as a fuel additive in a single-cylinder diesel engine while reducing emissions. Research findings will contribute significantly to improving the physical and chemical properties of diesel and octanol blends, thereby mitigating the challenges of limited petroleum reserves and environmental concerns. A range of different blends of diesel and octanol were prepared on a volume/volume basis in proportions of D70OCT30, D60OCT40, and D50OCT50, and then GO was added as a fuel additive to the abovementioned blends in varied proportions (40, 60, and 80 ppm) resulting in nine blends. These blends were analyzed in terms of various performance, combustion, and emission characteristics, and the obtained results helped to shed light on the impact of GO as a fuel additive. The results indicated that the fuel blend D70OCT30GO0.006 yielded the highest values. Furthermore, it is highly imperative that we develop a model that can be used to predict engine behavior and its stability without having to run an engine. For this, a data-driven artificial neural network (ANN) model was developed to predict the optimized injection timing for better combustion and reduced emission. The efficiency and prediction capabilities of the model were compared to the experimental data, which indicated that the ANN model had a better prediction score. The injection timing of the engine was optimized from 21 °CA to 21.5 °CA, which increased the efficiency by 1%. The research findings showed significantly improved physical and chemical properties of the blends, thereby mitigating the challenges of limited petroleum reserves and environmental concerns.

Comprehensive Analysis of Compression Ratio, Exhaust Gas Recirculation, and Pilot Fuel Injection in a Diesel Engine Fuelled with Tamarind Biodiesel

The global automotive industry is facing significant challenges, including dwindling fossil fuel reserves, rising crude oil prices, and increasingly strict emission regulations. To address these concerns, this study investigates the impact of the compression ratio (CR) and exhaust gas recirculation (EGR) on the performance and emissions of a common rail direct injection (CRDI) diesel engine fuelled with a 20% blend of tamarind seed methyl ester (TSME 20) biodiesel. The study employed an open-type electronic control unit to implement pilot fuel injection at a rate of 30%, 23° before the top dead centre (TDC), and at a higher pressure of 600 bar. Three CRs (16:1, 18:1, 20:1) and two types of EGR (hot and cold EGR at 10%) were evaluated. Diesel fuel at CR 18 was used as a baseline for comparison. The experimental procedure involved conducting tests with TSME 20 at CR 16, 18, and 20. Subsequently, TSME 20 at CR 20 + Hot EGR 10% and TSME 20 at CR 20 + Cold EGR 10% were examined. The results showed that TSME 20 operated at a higher CR (CR 20) exhibited improved diesel engine performance and significant reductions in harmful exhaust emissions. Additionally, cold EGR at 10% was more effective in reducing CO, CO2, and NOx emissions from TSME 20 than hot EGR. The findings of this study provide valuable insights into optimizing diesel engine operation to achieve a balance between performance enhancement and emission reduction through tamarind seed biodiesel blends and different EGR techniques. The implementation of these strategies holds considerable potential in addressing the automotive industry’s challenges, including ecological considerations and fuel price fluctuations.

Correction: Characterization from Diesel and Renewable Fuel Engine Exhaust: Particulate Size/Mass Distributions and Optical Properties

Correction: Characterization from Diesel and Renewable Fuel Engine Exhaust: Particulate Size/Mass Distributions and Optical Properties

Validation of the estimated ships' emissions through an experimental campaign in port

This paper presents a correlation between the gaseous pollutant concentration measured in port and the estimated in-port ship emissions based on AIS data for the port of Naples. With the aim of better monitoring the quality ship's plumes funnels, the concentrations of Nitrogen dioxide (NO2) and Sulphur dioxide (SO2) have been continuously measured, during an experimental campaign (May–June 2021) at a height of 20 m from ground level.An innovative bottom-up ship emission modeling system with an emission inventory was created; five principal steps were realized: acquisition and cleaning, construction of ship's database, analysis of ship routes and phases in port, calculation of fuel consumption, and emission. The updated methodology bypasses the typical fixed value of specific fuel consumption, which is obtained based on the engine type and fuels and uses a correlation with the real engine load. Several updates were adopted for the emission estimation, abandoning the constant emission factor with the use of a more detailed methodology. The correlation was obtained by taking into account the prevailing winds and the overlap between the experimental campaign and the emission inventory on particular wind sectors. As a results correlations between the pollutant flow rates estimated from the AIS data and the concentrations measured during the experimental campaign, have been find (0.97 for SO2 and 0.80 for NOX).