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The internal combustion engine continues to be the main source of power in various modes of transport and industrial machines. This is due to its numerous advantages, such as easy adaptability, high efficiency, reliability and low fuel consumption. Despite these beneficial qualities of internal combustion engines, growing concerns are related to their negative environmental impacts. As a result, environmental protection has become a major factor determining advancements in the automotive industry in recent years, with the search for alternative fuels being one of the priorities in research and development activities. Among these, fuels of plant origin, mainly alcohols, are attracting a lot of attention due to their high oxygen content (around 35%). These fuels differ from diesel oil, for instance, in kinematic viscosity and density, which can affect the formation of the fuel spray and, consequently, the proper functioning of the compression–ignition engine, as well as the performance and purity of the exhaust gases emitted into the environment. The process of spray formation in direct injection compression–ignition engines is extremely complicated and requires detailed analysis of the fast-changing variables. This explains the need for using complicated research equipment enabling visualisation tests and making it possible to gain a more accurate understanding of the processes that take place. The present article aims to present the methodology for alternative fuel visualisation tests. To achieve this purpose, sprays formed by diesel–ethanol blends were recorded. A visualisation chamber and a high-speed camera were used for this purpose. The acquired video provided the material for the analysis of the changes in the vertex angle of the spray formed by the fuel blends. The test was carried out under reproducible conditions in line with the test methodology. The shape of the fuel spray is impacted by an increase in the proportional content of ethanol in the diesel and dodecanol blend. Based on the present findings, it is possible to note that the values of the vertex angle in the spray produced by the diesel–ethanol blend with the addition of dodecanol are most similar to those produced by diesel oil at an injection pressure of 100 MPa. The proposed methodology enables an analysis of the injection process based on the spray macrostructure parameters, and it can be applied in the testing of alternative fuels.

The n-butanol/low-carbon alcohol/diesel microemulsion system is a good alternative fuel to diesel. In this study, the microemulsions were formulated in four ways: ultrasonication, vortex oscillation, shaker mixing and spontaneous formation. The results reveal that the ultrasonication method is significantly influenced by temperature. Specifically, at 45 °C, the quantity of cosolvent added during the ultrasonic process can be reduced by a maximum of 25% compared to that at 25 °C. However, while the amount of cosolvent required is the lowest at 45 °C, the stability of the emulsion is the poorest. In all cases of this study, the stability of the microemulsion increases when the volume ratio of the lower carbon alcohol exceeds 60%. The lowest amount of co-solvent and high stability were achieved using the shaker mixing method at both 25 °C and 35 °C. Although the quantity of cosolvent required at 45 °C is second only to the lowest, its stability surpasses that of the ultrasonication method. Therefore, it is more effective to choose the shaker mixing method that provides uniform and ordered forces for the preparation of microemulsion liquids.

There is a heightened risk of an oil spill occurring in the Arctic, as climate change driven sea ice loss permits an increase in Arctic marine transportation. The ability to detect an oil spill and monitor its progression is key to enacting an effective response. Microwave scatterometer systems may be used detect changes in sea ice thermodynamic and physical properties, so we examined the potential of C-band polarimetric radar for detecting diesel fuel beneath a thin sea ice layer. Sea ice physical properties, including thickness, temperature, and salinity, were measured before and after diesel addition beneath the ice. Time-series polarimetric C-band scatterometer measurements monitored the sea ice evolution and diesel migration to the sea ice surface. We characterized the temporal evolution of the diesel-contaminated seawater and sea ice by monitoring the normalized radar cross section (NRCS) and polarimetric parameters (conformity coefficient (μ), copolarization correlation coefficient (ρco)) at 20° and 25° incidence angles. We delineated three stages, with distinct NRCS and polarimetric results, which could be connected to the thermophysical state and the presence of diesel on the surface. Stage 1 described the initial formation of sea ice, while in Stage 2, we injected 20L of diesel beneath the sea ice. No immediate response was noted in the radar measurements. With the emergence of diesel on the sea ice surface, denoted by Stage 3, the NRCS dropped substantially. The largest response was for VV and HH polarizations at 20° incidence angle. Physical sampling indicated that diesel emerged to the surface of the sea ice and trended towards the tub edge and the polarimetric scatterometer was sensitive to these physical changes. This study contributes to a greater understanding of how C-band frequencies can be used to monitor oil products in the Arctic and act as a baseline for the interpretation of satellite data. Additionally, these findings will assist in the development of standards for oil and diesel fuel detection in the Canadian Arctic in association with the Canadian Standards Association Group.

The combustion of diesel fuel in internal combustion engines faces challenges associated with excessive emissions of pollutants. A direct solution to this issue is the incorporation of cleaner energy sources. In this study, a numerical model was constructed to investigate the characteristics of ammonia–diesel dual-fuel application in a medium-speed diesel engine. Effects of ammonia–diesel blending ratios on engine performance and emissions were investigated. The results indicate that for this engine model, the optimal diesel energy ratio is about 22%. When the diesel energy ratio is less than 22%, the engine’s output performance is significantly affected by the diesel energy ratio, while above 22%, the influence of the intake becomes more pronounced. When the diesel energy ratio is below 16%, the cylinder cannot reach combustion conditions. Diesel energy ratios below 22% can cause ammonia leakage. With increasing diesel energy ratio, the final emissions of carbon oxides increase. With a higher diesel energy ratio, NO emissions become lower. When the diesel fuel energy ratio exceeds 22%, the N2O emissions can be almost neglected, while below 22%, with poor combustion conditions inside the cylinder, the N2O emissions will increase.

In this study, the constant temperature control system of a heating plate was established, ethanol–diesel fuel with different proportions was prepared, and a series of experiments were carried out. The experimental system was used to observe, summarize, and analyze four evaporation and crushing modes of mixed droplets, which were explosion, liquid filament stretching, exocytosis, and ejection mode. The evaporation process of four kinds of mixed droplets in their life cycle was analyzed by normalizing the diameter square. It was proposed that the evaporation process of droplets could be divided into the following three stages: a heating stage, a fluctuating evaporation stage, and an equilibrium evaporation stage. It was also pointed out that the expansion, ejection, and micro-explosion of droplets were the causes of fluctuating evaporation. The concept of expansion and crushing intensity was put forward and the expansion and crushing intensity of ethanol/diesel mixed droplets with different proportions were calculated. The reasons why expansion and crushing intensity first increased and decreased with the increase in ethanol blending ratio were analyzed. Finally, the time proportion of ethanol–diesel mixed droplets in each evaporation stage was calculated, which explained that the time proportion of the instantaneous heating stage showed a parabolic law with the increase in ethanol content.

This study deals with the evolution of fuels’ prices over time in the EU. The central research inquiry revolves around whether there exists any correlation among the trajectories followed by national prices in the gasoline and diesel markets. The EU, and more specifically the Euro-Area, by its construction, is treated as an OCA (Optimum Currency Area). In an OCA, certain conditions are met to ensure the smooth functioning of a common currency. The fuel price synchronization is essential because it contributes to the effective implementation of policies and promotes stability across the entire macroeconomy. The study covers the period of 2017–2022. For each type of fuel and year, we construct an individual network where network nodes represent the EU member states while the edges connecting these nodes represent strong temporal fuel price correlations among the member states. The properties of the resulting networks are analyzed within a Complex Network framework. Our goal is twofold: first, to detect any potential convergence or divergence in the trajectories of the prices, and second, to investigate the impact of tax and duty implementation on the co-movements of the prices. The empirical findings show that diesel markets have a more pronounced pattern of price co-movements compared to the gasoline markets. Moreover, the application of fuel taxation policies seems to adversely affect the co-movements of prices.

Diesel is consistently a very popular fuel for internal combustion engines. Its consumption in the European Union has been rising over recent years, as has the number of engines increasingly sensitive to fuel contamination. One of the most important parameters affecting diesel quality is water content. Its exceedance of the standard’s permissible amount carries the risk of serious damage to expensive, modern fuel injection systems. Current methods of measuring water content require both specialised personnel and equipment, as well as transporting the sample to a suitable laboratory. Analysing the properties of diesel is challenging, mainly because many types of the fuel are sold, the chemical composition of which is always a well-guarded manufacturer’s secret. The research presented in this paper is aimed at verifying whether it is possible to test the moisture content of diesel using impedance spectroscopy. To date, it is the first such attempt with commercially available diesel using this method, which, once refined, could be used in situ. The authors propose and apply a novel technique that is able to be used when the electrical properties of tested oils are unknown. The experimental results obtained show that it is possible to use impedance spectroscopy to estimate the water content of different types of diesel fuel. The measurement accuracy achieved makes it possible to detect approaching or exceeding the permissible water content.

The promotion and growth in the use of diesel fuel in passenger cars in the UK and Europe over the past two decades led to considerable adverse air quality impacts in urban areas and more widely. In this work, we construct a multi-decade analysis of passenger car emissions in the UK based on real driving emissions data. An important part of the study is the use of extensive vehicle emission remote sensing data covering multiple measurement locations, time periods, environmental conditions and consisting of over 600,000 measurements. These data are used to consider two scenarios: first, that diesel fuel use was not promoted in the early 2000s for climate mitigation reasons, and second, that there was not a dramatic decline in diesel fuel use following the Dieselgate scandal. The strong growth of diesel fuel use coincided with a time when diesel NOx emissions were high and, conversely, the strong decrease of diesel fuel use coincided with a time when diesel vehicle after-treatment systems for NOx control were effective. We estimate that the growth in diesel car use in the UK results in excess NOx emissions of 721 kt over a three decade period; equivalent to over 7 times total annual passenger car NOx emissions and greater than total UK NOx emissions of 681.8 kt in 2021 and with an associated damage cost of £5.875 billion. However, the sharp move away from diesel fuel post-Dieselgate only reduced NOx emissions by 41 kt owing to the effectiveness of modern diesel aftertreatment systems.

While the surrogate fuel approach has been successfully applied to the simulation of the combustion behaviors of complex gasoline and jet fuels, its application to diesel fuels has been challenging. One of the main challenges derives from the large molecular size of the representative surrogate components necessary to simulate diesel blends, as the development of detailed chemical kinetic models and their validation becomes more complex. In this study, a new surrogate mixture that emulates the chemical and physical properties of a well-characterized diesel fuel is proposed. An optimization procedure was used to select surrogate components that can match both the physical and chemical properties of the target diesel fuel comprehensively. The surrogate fuel mixture composition was designed to have fuel properties (e.g., boiling point, cloud point, etc.) that enable its use in future diesel engine experiments. A detailed kinetic model for the surrogate fuel mixture was developed by combining well-validated sub-mechanisms of each surrogate component from Lawrence Livermore National Laboratory. The ability of the surrogate mixture and kinetic model to emulate ignition delay times was assessed by comparing the simulated results with measurements for the target diesel fuel. Comparison of the experimental and simulated ignition delay times shows that the current surrogate mixture and kinetic model well capture the autoignition response of the target diesel fuel at varying conditions of pressure, temperature, oxygen concentration, and fuel concentration. The current study is one of the first to demonstrate the efficacy of detailed chemical kinetics for diesel range fuels by assembling validated sub-mechanisms for palette compounds and successfully simulating the autoignition characteristics of a target diesel fuel. The experimental ignition delay times of diesel measured with a rapid compression machine, the surrogate mixture, and the kinetic model developed shall aid in progress of understanding diesel ignition under engine relevant conditions.

• Properties of Multiple biodiesel blends tested as per ASTM standards. • Mean gas temperature increases with increase in biodiesel concentration. • 18.93% increment in NOx is due to predominant effect of mean gas temperature. • ANN feed-forward backpropagation (TRAINLM and LEARNGDM) model predicts NOx by 0.99. This research paper focuses on modelling of nitrogen oxides emitted by diesel engine for multiple biodiesel blends. A lot of research work has observed that the properties of biodiesel blends affect the nitrogen oxide emissions. To this aim, total of fifteen blends of multiple biodiesels are prepared on vol. % by using four non-edible category biodiesels. The suitability and quality of the biodiesel and diesel blends are tested through a characterization and found within the permissible limits of ASTM. The experimentation has been carried out on a direct injection compression ignition (DICI) engine with constant speed and varying loading condition from no load to full load in a step of 25%. During the experimentation, the NOx emissions are measured using a Netel MGA-2 exhaust gas analyzer. The study revealed that several properties such as viscosity, density, mean gas temperature, etc. affect NOx emission. In addition, NOx emission increases with an increase in BPs. The artificial neural network (ANN) is performed by considering physicochemical and thermal properties as a function. The ANN predicts the estimated NOx with an accuracy of 0.99. [ABSTRACT FROM AUTHOR]

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The article focuses on the potential benefits of switching the fuel for the Ankerlig peaking plant in South Africa from diesel to liquefied petroleum gas (LPG) to reduce costs, improve greenhouse gas emissions, and address the country's ongoing issue of load shedding. Topics discussed include the significance of the proposed fuel change, the current challenges with load shedding in South Africa, the economic and technical feasibility of using LPG as an alternative to diesel.

The development of cost-effective technologies for the treatment of water contaminated by petrochemicals is an environmental priority. This issue is of paramount importance for countries like Saudi Arabia owing to its scarce water resources. Of particular concern are automobile fuels, such as gasoline and diesel, that can contaminate water aquifers from leaking underground fuel storage tanks. Owing to the cost-effectiveness of adsorption-based technologies, low-cost high surface-area commercial activated carbon was used for the adsorptive removal of contaminants from the emulsified fuel-contaminated water. Batch equilibrium experiments showed a high efficacy of the adsorbent. Even with small amounts of the adsorbent, a removal efficiency of more than 97% was obtained for both gasoline as well as diesel. Three different well-known batch adsorption isotherm models, namely the Langmuir, Freundlich, and Temkin, were used for describing the experimental data. The best results were obtained using the Freundlich isotherm followed by the Langmuir model. The maximum capacity was found to be 8.3 g gasoline and 9.3 g diesel per gram of the adsorbent at ambient conditions for a neutral contaminated aqueous solution. [ABSTRACT FROM AUTHOR]

The addition of Compressed natural gas as a complement to diesel in compression ignition engines in dualfuel combustion mode is a viable technology for increasing efficiency and lowering emissions. This work investigates the impact of a dual-fuel operating mode on the engine exhaust pollutant emissions of a diesel engine using compressed natural gas as the principal fuel and neat diesel as the pilot fuel. Compressed natural gas was injected into an intake manifold of a single-cylinder diesel test engine under different engine operating parameters, and up to 80% substitution was attained. And diesel fuel was injected after the compressed natural gas air mixture was compressed. The tests were carried out at five different compression ratios ranging from 13:1 to 15:1 in steps of 0.5:1. The experiment study revealed that injecting CNG into diesel engines via dual fuel combustion significantly impacted exhaust gas emissions compared to pure diesel combustion. The Carbon monoxide (CO) and hydrocarbon (HC) emissions were increased, while carbon dioxide (CO2), nitrogen oxide (NOX) and smoke opacity were decreased in dual fuel combustion compared to single diesel fuel. [ABSTRACT FROM AUTHOR]

Combustion systems can use tire pyrolysis oil (TPO) due to its high energy content. The amount of nitrogen and sulfur present in the TPO should result in NOx and SO2 emissions when combustion occurs. A flameless combustion regime can reduce pollutant emissions, mainly NOx, with greater thermal efficiency. This work aims to analyze the NO and NO2 emission in different diesel fuel mixtures with TPO, 5% (TPO5), and 10% (TPO10) by mass, in a flameless regime. A combustor was used operating with a maximum heat input of 13 kW and an effervescent injector promoting an average Sauter diameter of 33.89 ± 3.77 µm. The uniform temperature profile within the combustor characterizes the flameless combustion regime that was reached after 50 min for diesel and after 40 min for TPO5 and TPO10 from the ignition. TPO5 and TPO10 have similar NO emissions in flameless combustion. The NO2 emission increases with the TPO content in the mixture. [ABSTRACT FROM AUTHOR]

Traditional selective catalytic reduction aftertreatment technologies used to reduce N O x are very limited at exhaust temperatures below 175 ° C. Therefore, under these low engine load conditions, having effective in-cylinder control of N O x emissions is important. Previous work by the authors explored the effect of fuel physical properties on the ability to control N O x in-cylinder. That work was limited to one direct injection near top dead center. Modern diesel high-pressure fuel systems have the capability of five or more injections in one engine cycle. A higher-volatility diesel fuel and high amounts of exhaust gas recirculation to delay ignition could provide an opportunity for reduction in engine-out N O x through an increased level of fuel premixing. By appropriately timing multiple short injections, a more optimal distribution of fuel in-cylinder may be achieved, which could reduce N O x while maintaining an efficient combustion phasing. A computational fluid dynamics model previously validated against experimental data was used to explore several injection strategies with increased levels of fuel premixing to assess the potential trade-offs between N O x and CO/unburned hydrocarbon (UHC) emissions and thus reduce reliance on the aftertreatment system for N O x control. The results show that the devised injection strategies resulted in an increased level of fuel premixing. However, none of the attempted injection strategies resulted in significant N O x reductions, and all strategies showed a significant increase in CO and UHC emissions. [ABSTRACT FROM AUTHOR]

In remote communities of Canada, diesel is the primary source of electricity and heat. Promoting sustainable and diverse means of heat and power generation is essential to providing reliable and less carbon-intensive energy supply to remote communities. Among renewable energy sources in Canada, biomass is a major source of energy, with wood pellets being a notable contributor. In this study, using wood pellets in a remote community of Canada is investigated using life cycle analysis (LCA). Furthermore, wood pellet combustion is compared with diesel combustion, the most common fossil fuel in these regions. SimaPro (version 8.4.0.0) was used with Ecoinvent 3 as the primary library because of the nature of the feedstock. Harvesting, transportation, sawmill operation, pelletization, and combustion stages are considered in LCA. In doing so, first, life cycle data related to each of these stages are collected with respect to eight impact categories of global warming, ozone depletion, carcinogenic, non-carcinogenic, smog, respiratory effects, acidification, eutrophication, ecotoxicity, and fossil fuel depletion. The results indicate that pelletization and combustion stages have the greatest environmental impact, specifically in terms of non-carcinogenic effects from pelletization and respiratory effects from pellet combustion. Additionally, when comparing wood pellets to diesel, wood pellet combustion exhibits superior performance across various impact categories, particularly in non-carcinogenic effects. [ABSTRACT FROM AUTHOR]

Ducted fuel injection (DFI) is an innovative method that curtails or prevents soot formation in direct-injection compression-ignition engines. DFI uses a simple duct, positioned outside each injector hole, facilitating the fuel/charge gas mixing before ignition. This reduces the equivalence ratio below two, in the autoignition zone, which in turn decreases soot formation. But this method also reduces fuel-conversion efficiency. This study investigates the effects of DFI on in-cylinder heat transfer. Experiments with conventional diesel combustion (CDC) and DFI were performed at four different dilution levels. Computational fluid dynamics (CFD) simulations were carried out at conditions matching those of the experiments, and the simulations were validated by the experimental data. The CFD simulations enabled to examine of in-cylinder heat release and temperature distributions. The heat transfer to the piston, head, and cylinder was investigated. The results show that DFI increased the heat transfer to the walls compared to CDC under the same conditions. This could help explain why DFI has been observed to reduce fuel-conversion efficiency by approximately 1% (absolute) relative to CDC under certain conditions. The efficiency loss typically decreases with dilution, such that DFI can improve fuel-conversion efficiencies relative to CDC at higher dilution levels. [ABSTRACT FROM AUTHOR]

Fossil fuels confront the problem of strategic resource depletion since they have been continuously utilized for more than 200 years and cause serious damages to the ecological environment of the planet. In this work, the transesterification of castor plant oil was utilized to make biodiesel, and castor biodiesel's physicochemical qualities were assessed. On a single-cylinder, four-stroke, water-cooled agricultural diesel engine, an experimental study was conducted to compare and analyze the engine performance and emission characteristics of diesel and biodiesel blends in various amounts. The B20, B40, B60, and B80 biodiesel blends were evaluated at different engine speeds (1200, 1400, 1600, and 1800 rpm) with a constant engine load (50%). According to the experimental findings, the brake thermal efficiency (BTE) declines as the engine speed rises, and the biodiesel fuel blend has a lower brake thermal efficiency (BTE) than diesel fuel because of its higher density and viscosity and lower calorific value. The amount of gasoline required to create power increases as the speed does, and the brake-specific fuel consumption (BSFC) trend is upward. Due to their low calorific value and high viscosity properties, biodiesel blends have a greater brake-specific fuel consumption (BSFC) than diesel. The fuel's exhaust gas temperature (EGT) has an upward trend with an increased rotational speed. The biodiesel blend's high cetane number shortens the ignition delay and lowers the exhaust gas temperature (EGT) compared to diesel. A fuel with oxygen added, biodiesel enhances combustion, increases the combustion temperature, speeds up the oxidation process, and lowers carbon monoxide (CO) and hydrocarbon emissions. B80 produces the lowest carbon monoxide and hydrocarbon emissions at 1800 rpm, at 0.33%, and 30 ppm, respectively. On the other hand, increased carbon dioxide (CO2) emissions result from a high oxygen concentration. In addition, compared to diesel fuel, biodiesel's greater combustion temperature causes the creation of increased nitrogen oxide (NOx) emissions. According to the research findings, a castor biodiesel fuel blend is an excellent alternative fuel for engines since it can be utilized directly without modifying the current engine construction and has good engine and exhaust emission performance. [ABSTRACT FROM AUTHOR]

The consumption of alternative fuels accelerated in recent years because of the depletion of petroleum fuel sources, and, nowadays, the blended fuel demand is increasing worldwide. Blended fuel structure and burning characteristics are significantly different from pure fuels. The combustion behavior of pool fire of n-propanol, diesel, and their blends was experimentally studied under quiescent ambient air conditions. The fuels were burned in a circular pan of three sizes (D = 0.20, 0.10, and 0.05 m) to explore the burning properties. Blends of diesel with n-propanol were tested with an n-propanol concentration of 10 and 30 % by volume. The mass burning rate (MBR), fuel temperature, and total heat flux from flames were recorded. The combustion parameters of diesel, n-propanol, and blends with different pans were comparable. The propanol fraction enhances the burning rate of diesel, and soot formation is less visible in blended fuels. The average MBR recorded for pure propanol in 0.20 m pan diameter is 0.01548 kg/m2.s. The mean fuel temperature difference between thermocouples in diesel is 40 °C, and n-propanol is 20 °C, and for P10, the temperature difference is closer to the diesel. Thermal heat flux is estimated by using a low-cost thin-film heat flux sensor. The total heat flux profile of 0.20 m diameter P10 and P30 blends develops a V-shaped curve between the burning time range of 300 to 650 seconds and 400 to 750 seconds. These characteristics of pool fire combustion aid in the safe storage and handling of blended fuel. [ABSTRACT FROM AUTHOR]

The utilization of hydrogen for reciprocating internal combustion engines remains a subject that necessitates thorough research and careful analysis. This paper presents a study on the co-combustion of hydrogen with diesel fuel and biodiesel (RME) in a compression-ignition piston engine operating at maximum load, with a hydrogen content of up to 34%. The research employed engine indication and exhaust emissions measurement to assess the engine's performance. Engine indication allowed for the determination of key combustion stages, including ignition delay, combustion time, and the angle of 50% heat release. Furthermore, important operational parameters such as indicated pressure, thermal efficiency, and specific energy consumption were determined. The evaluation of dual-fuel engine stability was conducted by analyzing variations in the coefficient of variation in indicated mean effective pressure. The increase in the proportion of hydrogen co-combusted with diesel fuel and biodiesel had a negligible impact on ignition delay and led to a reduction in combustion time. This effect was more pronounced when using biodiesel (RME). In terms of energy efficiency, a 12% hydrogen content resulted in the highest efficiency for the dual-fuel engine. However, greater efficiency gains were observed when the engine was powered by RME. It should be noted that the hydrogen-powered engine using RME exhibited slightly less stable operation, as measured by the COVIMEP value. Regarding emissions, hydrogen as a fuel in compression ignition engines demonstrated favorable outcomes for CO, CO2, and soot emissions, while NO and HC emissions increased. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to address the importance of predicting fuel prices due to their impact on the economy and welfare of people in Dar es Salaam city and regions in Tanzania. Design/Methodology/Approach: This study follows the quantitative research design by utilizing secondary data. The sample data consists of monthly petrol and diesel prices in Dar es Salaam from January 2015 to May 2023. The ARIMA model was employed to analyze the time series data with model identification, estimation, and verification steps performed using statistical techniques such as the ADF test, ACF, PACF, and AIC. Findings: The findings indicated that the ARIMA (0,1,1) model was the best-fitted model for forecasting both petrol and diesel prices in Dar es Salaam. The forecasted values for the next six months show that models demonstrated good performance in predicting petrol and diesel prices. Research Limitation/Implication: Some of the potential limitations of this study include the reliance on secondary data, the assumptions of stationarity and linearity in the ARIMA model, and the sensitivity of the forecast to future data. Also, the study focuses specifically on Dar es Salaam which may limit the generalizability of the findings in other regions. Social Implications: This study has significant social implications for residents of Dar es Salaam, offering insights for household budgeting, transportation planning, and predicting fuel price changes. It also informs social programs and subsidies, contributing to equitable and sustainable community development. Practical Implications: The study has practical implications for the stakeholders in the fuel industry, policymakers, and consumers in Dar es Salaam. The accurate prediction of petrol and diesel prices can assist consumers in making informed decisions regarding pricing, budgeting, and fuel consumption which helps to reduce the risk of fuel loss and optimize their fuel-related choices. Originality/Value: The novelty of this study is analyzing historical fuel price data in Dar es Salaam using ARIMA models. Through this approach, we identify trends, seasonality, and cyclical patterns unique to the region. This knowledge adds to the existing understanding of fuel price determinants in the local context. [ABSTRACT FROM AUTHOR]

Microemulsion fuels, also known as surfactant-free fuels, are fuels made from a combination of two immiscible liquids, hydrocarbon fuel, and water, with a trace quantity of a co-solvent. Surfactants are often used in conventional microemulsion fuels, however surfactant-free microemulsion fuels instead depend on the thermodynamic features of the combination to generate a stable emulsion. In this paper, the multi-criteria decision-making (MCDM) model for choosing microemulsion fuel with surfactant-free. Various helpful and harmful criteria were evaluated for ten fuels at varying motor loads, according to performance and emission characteristics. This paper integrated the neutrosophic set with the TOPSIS method. The neutrosophic set is used to deal with uncertain data. The TOPSIS method is used to rank the different fuels. [ABSTRACT FROM AUTHOR]

This study examined the potential of using coconut fatty acid distillate (CFAD), a by‐product of the processing of edible oils, as a diesel engine fuel. The major novelty of this study is to assess the CFAD as a viable feedstock of biodiesel to address global energy demands. CFAD has not been specifically researched as a feedstock for producing biodiesel or as a fuel for diesel engines, despite the fact that numerous studies on the production and performance of biodiesel have already been conducted. Fourier transform infrared (FTIR) spectroscopy, gas chromatography (GC), and FTIR were used to analyze the fuel. According to the results of the GC test, CFAD oil contains 91.53% saturated fatty acids, compared with only 8.47% unsaturated fatty acids. High saturation values can be seen in myristic acid (16.92%) and lactic acid (45.33%). Longer hydrocarbon chain lengths indicate higher energy density and boiling point, which also indicate lesser volatility. At a frequency of 1708.54 cm−1, C─H stretching vibrations have been identified through FTIR investigation. The vibrations of C─C stretching at 1465.47 cm−1 indicate the presence of alkenes/fingerprint phase. The blends used for this investigation include 90% diesel with 10% CFAD (CFAD10), 80% diesel with 20% CFAD (CFAD20), 70% diesel with 30% CFAD (CFAD30), and 100% CFAD. The CFAD 10%, 20%, and 30% blends as well as the CFAD100 had brake thermal efficiency values of 27.24%, 26.23%, 24.88%, and 21.52%, correspondingly, at full load. The average increment in brake‐specific energy consumption for CFAD10, CFAD20, CFAD30, and CFAD100 over diesel fuel was 8.23%, 10.88%, 13.77%, and 25.90%, respectively. The behavior of CFAD exhibits reduced cylinder pressure because of the large content of moderate saturated fatty acids in this substance. The net heat release rate (NHRR) and cylinder pressure have a similar relationship in that the NHRR increases with increasing diesel volume. In comparison to diesel, the CO emissions from the CFAD20, CFAD30, and CFAD100 blends increased by 10.79%, 16.66%, and 35.89% at maximum load, respectively. It has been reported that NOx is reduced more significantly the more CFAD is present in the mixture. The blend CFAD10 had the least amount of smoke. The high viscosity of the CFAD and its blends influences the fuel droplets range and the development of spray in the cylinder, which results in delayed combustion and higher unburned hydrocarbon emissions. [ABSTRACT FROM AUTHOR]

In this research, waste stream essential oil such as orange oil is used as a diesel fuel partial replacement to be tested in a diesel engine. Like diesel fuel, orange oil does not contain any oxygen since it is constituted of limonene (a colourless liquid aliphatic hydrocarbon) and has almost similar density. A 6-cylinder diesel engine is operated using various blends of orange and diesel fuel. The engine was operated with three different fuel blends: neat diesel, 74% diesel + 26% orange oil (D74O26) and 59% diesel + 41% orange oil (D59O41). All the orange oil blends produced nearly the same brake power from the engine experiment compared to neat diesel fuel. Furthermore, all orange oil blends emit less particulate matter, and the 'count mean diameter' of the emitted particles is also lower than base diesel. Based on the obtained results, these blends can be suggested to be used in a diesel engine. [ABSTRACT FROM AUTHOR]

The level of electricity generation in Nigeria is presently grossly inadequate. Consequently, the productive sectors of the economy do not presently enjoy an uninterrupted supply of electrical energy from the country’s national grid and the downtime is in most cases too much. Using diesel-fueled electric power generators has become an attractive alternative to meet the shortfall in the energy supply gap. In this study, the levels of polycyclic aromatic hydrocarbons in the vicinity of the diesel-fueled electric power generators operated by Osun State University, Osogbo, Nigeria were investigated with a view to ascertain the priority levels and carcinogenic PAHs. Since the generators were recently relocated, the study covered the old and the new sites. Polyurethane foam passive samplers were deployed at the old and new sites for 28 days. They were subjected to sohxlet extraction using dichloromethane to extract the PAHs from the PUFs. Cleaning up and elution were done with 5 g of silica gel column and 40 mL 1:1, DCM:Hexane followed by concentration in a rotary evaporator using a stream of nitrogen. Gas chromatographymass spectrometry (GC-MS) analysis was used to determine of PAHs. The Ʃ priority PAHs around the old and new sites were in the range of 4.43-5.44 μg/m3 and 4.47-5.35 μg/m³, respectively. The Ʃ carcinogenic PAHs at the sites were 2.98 -3.42 μg/m³ and 3.35 - 4.17 μg/m³ . Higher molecular weight PAHs dominated the measured PAHs with benzo[a]pyrene being the most significant contributor to the computed total toxicity equivalence (TTEQ). The PAHs diagnostic ratios affirmed that the measured PAHs were from dieselrelated sources. The levels of the PAHs obtained in this study are above permissible limits specified for ambient air; hence, the air around the power plant is considered unsafe. [ABSTRACT FROM AUTHOR]

Restrictions imposed by regulatory frameworks, the high cost of fuels, environmental impacts and the efficiency of internal combustion engines encourage research into reducing the consumption of fossil fuels. Additionally, to think about the alternative energy sources. In compression ignition engines, researchers around the world have been working for years on the use of biodiesel fuel, in order to reduce emissions and the consumption of diesel fuel. In other investigations, water electrolysis products obtained in an HHO gas generator and supplied to an internal combustion engine allow for improving performance, reducing fuel consumption and emissions. HHO gas is a mixture of hydrogen and oxygen resulting from the electrolysis process of water, with energy supplied by an electric source or accumulator. The main objective of this work is to evaluate the influence of an HHO generator products in a diesel engine that operates with diesel fuel produced in Colombia with 10 % biodiesel. The objective of this study is evaluated the influence of gas HHO on mechanical performance, fuel consumption, and polluting emissions in a single-cylinder diesel engine, performing a comparative analysis when the HHO generator operates with different amperages. The results showed a 25 % average reduction in fuel consumption between 1500 by 2500 engine revolutions when the HHO cell operated with 8 amperes. The breaking power maximum value increased a 10 %, and CO and PM10 emissions were reduced by 14 % and 53 %, respectively, at 1000 rpm. It is possible to conclude that supplying water electrolysis products in the fuel-air mixture increases the mechanical performance of a diesel engine and reduces polluting gas emissions. Additionally, research areas are opened in the development of HHO generators and standards for the application of this technology. [ABSTRACT FROM AUTHOR]

Optical properties analysis is not included in biodiesel quality standards. However, it provides valuable information about biodiesel and its feedstocks. In particular, very accurate refractive index measurements can be carried out using low‐cost (less than 1000 USD) and fast (a few seconds) equipment. Therefore, the most urgent question is to determine if the optical properties are a suitable tool for the biodiesel industry and in which applications they can currently be implemented. This work provides a comprehensive and systematic analysis of literature dealing with applications of refractive index measurements of biodiesel, its feedstocks and its blends with other fuels. Experimental data, typical ranges of values and mathematical models of refractive index are systematically presented and discussed, emphasizing biodiesel mixtures with diesel fossil fuel. Other applications, like transesterification monitoring, combustion, atomization and aging are also reviewed. At the present state of knowledge, measurements of refractive index can be used to determine the proportion of diesel and biodiesel blends and monitor the transesterification reaction. [ABSTRACT FROM AUTHOR]

Biodiesel is widely used pure or mixed with diesel fossil fuel in diesel engines. Standards for determining biodiesel quality establish limits for the values of several physicochemical properties. However, the procedures to determine many properties are time‐consuming and demand specialized personnel and expensive equipment. Other methods to characterize biodiesel, such as electrical methods, are particularly interesting. Measurements of electrical properties (permittivity and conductivity) give valuable information about biodiesel, its feedstocks, and its blends with fossil fuel diesel, and solve the usual cost and time drawbacks. This work aims to present a thorough and systematic review of the literature on applications of electrical properties measurements of biodiesel, its feedstocks, and mixtures with other fuels. An overview of the experimental data, typical ranges of values, prediction models, and applications is presented and analyzed in detail, emphasizing blends of biodiesel with fossil fuel diesel. Correlations with important properties (kinematic viscosity, methanol content) are reviewed. Applications include transesterification monitoring, biodiesel aging, the detection of contaminants and electromagnetic heating. This research aimed to determine whether electrical properties are a valuable tool for the biodiesel industry, and what applications may be realized in light of current scientific development. It was determined that, in the current state of research, permittivity measurements could be used to accurately determine the amount of diesel and biodiesel in mixtures. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

One way to cut down the consumption of diesel fuel in domestic heating in Jordan is to blend it with shale oil, which may be extracted from oil shale. This leads to a cut down in the national fuel bill in Jordan. Unfortunately, shale oil contains significant amounts of sulfur as impurities and upon burning sulfur oxides are emitted causing a negative environmental impact, and hence desulfurization of such fuel blends is essential. This may be achieved by adding activated carbon to the fluids. The process of removing sulfur from shale oil is crucial for safeguarding the environment, human well-being, and equipment, as well as meeting regulatory requirements and creating superior-quality goods. In this study, a domestic boiler was utilized to evaluate the degree of desulfurization process of blends of diesel and shale oil fuels upon their burning in a domestic boiler, to achieve this, blends of both fuels were prepared with varying amounts of shale oil (10%, 20%, 30%, and 40%) and various amounts of activated carbon were added to the prepared mixtures of diesel fuel and shale oil. The assessment of performance included examining the environmental impact, specifically by analyzing exhaust gases to measure the concentration of Sulfur Oxide (SO2). It was found that an increase in the concentration of shale oil in the mixture led to an increase in the concentration of SO2. However, adding more activated carbon to the mixture from the fuels resulted in a decrease in the SO2 concentration. The lowest SO2 concentration was observed when 1g of activated carbon was added per liter of the fuel mixture at a 20% concentration of shale oil, and 0.6g of activated carbon per liter of the fuel mixture at a 40% concentration of oil shale. [ABSTRACT FROM AUTHOR]

This work involves a detailed study on the transesterification process of waste and non-edible seed oil derived from Capparis spinosa (CSBD) to fuel research diesel engines. The positive claim of employing non-edible seeds shall reduce fossil fuel usage. This work examines the study on CSBD on transesterification and the emission patterns of a 4-stroke research diesel engine. Emission patterns were calculated in various circumstances by changing CSBD percentage (10 and 20% volume) and diesel. Ten and 20% vol of CSBD blended with 90, and 80% of petro-diesel is referred to as D90CSBD10 and D80CSBD20, respectively. Results revealed that the CO, HC, and smoke opacity were lower with a slight increase in NO emissions for all CSBD blends than diesel. Hence, this study concluded that the fuel obtained from Capparis spinosa oil is a viable alternate to diesel. [ABSTRACT FROM AUTHOR]

The subsidy policy of diesel in Indonesia is considered inefficient since it results an increase in the burden on the Government Budget (APBN), distribution process is not well targeted and encourages wastage of consumption. Then, in 2014 the Indonesia government decided to cut diesel subsidies and began marketing alternative solar products, namely biodiesel, as an effort to ensure energy sustainability. Therefore, this study aims to analyze the determinant that influences household’s willingness to use biodiesel using quantitative methods. The results show that there are three variables having a significant effect on the willingness to use biodiesel, namely age, occupation, and knowledge. [ABSTRACT FROM AUTHOR]

The article presents simulation strength calculations of a newly designed crankshaft for a PZL 100 engine with a reciprocating piston design. This engine is the subject of a research and development project co-financed by NCBR. The article presents four successive versions of the crankshaft geometric changes which underwent strength calculations. Such elements as the outer and inner parts of the crankshaft arm were changed in these geometric versions. The geometry of the shaft was changed using Catia v5 software, while strength calculations were carried out in Abaqus software. In summary, one of the presented models was selected for further work due to the possible simplification of the manufacturing process and the reduction of mass and stresses. This model was further investigated in the project. [ABSTRACT FROM AUTHOR]

Due to unique properties, production and operation features, water-fuel emulsion (WFE) could be considered as one of the most promising type of alternative fuels for diesel engines. Experimental research showed that compared to traditional diesel fuel, application of water-fuel emulsion allows to reduce nitrogen oxides and soot emissions, which is due primarily to a decrease in the level of maximum temperatures in the engine cylinder, as well as a more uniform distribution of fuel over the combustion chamber volume thanks to its secondary dispersion (micro-explosion phenomena). To control the stability of water-fuel emulsion properties during engine operation it is recommended to install water content sensor in the fuel supply system. [ABSTRACT FROM AUTHOR]

Research has confirmed that the utilisation of Antarctic microorganisms, such as bacteria, yeasts and fungi, in the bioremediation of diesel may provide practical alternative approaches. However, to date there has been very little attention towards Antarctic microalgae as potential hydrocarbon degraders. Therefore, this study focused on the utilisation of an Antarctic microalga in the bioremediation of diesel. The studied microalgal strain was originally obtained from a freshwater ecosystem in Paradise Bay, western Antarctic Peninsula. When analysed in systems with and without aeration, this microalgal strain achieved a higher growth rate under aeration. To maintain the growth of this microalga optimally, a conventional one-factor-at a-time (OFAT) analysis was also conducted. Based on the optimized parameters, algal growth and diesel degradation performance was highest at pH 7.5 with 0.5 mg/L NaCl concentration and 0.5 g/L of NaNO3 as a nitrogen source. This currently unidentified microalga flourished in the presence of diesel, with maximum algal cell numbers on day 7 of incubation in the presence of 1% v/v diesel. Chlorophyll a, b and carotenoid contents of the culture were greatest on day 9 of incubation. The diesel degradation achieved was 64.5% of the original concentration after 9 days. Gas chromatography analysis showed the complete mineralisation of C7–C13 hydrocarbon chains. Fourier transform infrared spectroscopy analysis confirmed that strain WCY_AQ5_3 fully degraded the hydrocarbon with bioabsorption of the products. Morphological and molecular analyses suggested that this spherical, single-celled green microalga was a member of the genus Micractinium. The data obtained confirm that this microalga is a suitable candidate for further research into the degradation of diesel in Antarctica. [ABSTRACT FROM AUTHOR]

The uncertainty in the supply of crude oil, increasing the number of vehicles and rising air pollution, especially in urban areas, has prompted us to look for alternative fuels. It is understood that using Compressed Natural Gas (CNG) in IC engines could be a mid-term solution to these problems. It is well established that CNG has better combustion characteristics and low emissions compared to conventional gasoline and diesel fuel. In the present study, an experiment was conducted to evaluate the engine performance and exhaust emissions using various percentages of CNG in dual fuel mode. CNG was mixed in the intake manifold’s air stream, and diesel was injected after the compression of the CNG air mixture. This paper presents experimental results of 40%,60%, and 80% CNG in the air stream. Engine performance and emissions are presented and discussed at a speed of 1200 rpm to 1500 rpm in steps of 50 rpm. The results of the experiments showed that adding CNG to diesel engines in dual-fuel combustion significantly impacted performance and emissions. Compared to single diesel fuel combustion, dual fuel combustion increases brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) at all CNG energy shares and engine speeds. Carbon monoxide (CO) and hydrocarbon (HC) emissions were increased, while nitrogen oxide (NOX) and smoke opacity were decreased in dual fuel combustion compared to single diesel fuel.

Nanomaterials (NMs) like copper oxides, titanium oxides, and aluminum oxides have been developing into some of the most promising fuel additives for diesel engines in recent years. in order to create a practical nano fuel. A significant amount of laboratory testing has been conducted up to this point to investigate the impact of using nano fuels on several aspects of diesel engine characteristics, particularly on hazardous emissions and engine performance (brake specific fuel consumption, effective power, brake thermal efficiency). This study provides an overview of the findings so far and the current situation regarding the use of nano fuels in diesel engines. Additionally, among the group of the most tested fuel additive nanoparticles, the best NMs/base fuel combinations are found based on two criteria that either involve all diesel engine parameters or simply diesel emissions. There are numerous techniques for improving engine performance. Nanoparticles can be used as catalysts in chemical reactions and feedstock pretreatment processes to produce biofuels. According to the overall findings, adding nanoparticles significantly reduced the amount of fuel used for brakes by 20% to 23% when compared to biodiesel-diesel blends with and without the addition of alcohol. In addition to improving the combustion process and boosting the brake power by 2.5% to 4%, nanoparticles have a high thermal conductivity. Emission data revealed that while HC, CO, and PM emissions all dramatically decreased in most reviews, NO emissions increased by up to 55%.

This study presents the effects of compressed natural gas fuel on a four-cylinder compression ignition engine. Compressed natural gas as the main fuel and diesel fuel as the igniter were used to investigate performance and emissions from the dual fuel engine. According to the engine speed and load, the amount of diesel fuel as igniter was adjusted using mechanical changes in the governor, while no ignition system was used. The engine experimental tests were performed at engine speeds of 1200, 1400, 1600, 1800 and 2000 rpm, using diesel fuel and dual fuel. These data were collected in the Engine Research Center of Tabriz Motorsazan Company and experimental runs were repeated three times. The maximum torque of the engine in diesel mode was 360 N m at 1400 rpm. Compared to the diesel mode, the dual fuel mode showed the maximum torque by 334 N m at 1600 rpm, which is about 26 N m less than that gained from the diesel mode. Considering emissions analysis at 2000 rpm, it is seen that the amount of NOX, HC, CO2 and CO emissions in the dual fuel mode was 20, 53, 16 and 86% more than diesel mode, respectively. However, O2 and soot showed the highest reduction at 2000 rpm for dual fuel mode by 51% and 69% respectively. This study indicated that there was a considerable enhancement in exhausted emissions when the injection of the diesel fuel as igniter was done mechanically. In this regard, control the amount and time of the igniter injection could likely be helped for better control of emissions. Therefore, further research on the modification of the diesel injection system as igniter or CNG injection system is needed towards reducing emissions.

Maintenance & Repair costs in heavy-duty trucks are an important component of the total cost of ownership. Due to the very limited availability of real-time data collected from medium- and heavy-duty vehicles using alternative fuels, this topic has not been well studied resulting in a very slow diffusion of alternative fuel vehicles in the market. This study focuses on collecting maintenance data related to diesel and alternative fuels such as natural gas and propane for the school bus, delivery truck, vocational truck, refuse truck, goods movement truck, and transit bus. The novelty of this work lies in identifying the mixed effects in the maintenance data and using a mixed-effect model for developing a single prediction model on clustered longitudinal data. A mixed-effect random forest machine learning model is trained on the maintenance data for estimating the average cost per mile. The model achieved an R2 of 98.96% with a mean square error of 0.0089 $\$ $ /mile for training and an R2 of 94.31% with a mean square error of 0.0312 $\$ $ /mile for the validation dataset. The prediction model is evaluated on each cluster of data and observed to perform well capturing the variations in each cluster very well. Furthermore, the performance of the mixed-effect random forest model is compared with the XGBoost ensemble model.