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In recent years, the number of automobiles has drastically increased. As a result, the need for energy in the transportation sector is continuously rising. Additionally, using fossil fuels results in many hydrocarbon emissions, carbon monoxide, carbon dioxide, and particulate matter, spoiling the environment. Renewable energy sources like solar power, biodiesel, wind turbine, bioethanol, methanol, hydrogen, and various biomasses from wastes become a great subject of interest. This paper includes biodiesel production from Nahar oil with two-step transesterification and the performance and exhaust emission in a four-cylinder diesel engine fueled with double-walled carbon nanotubes blended with Nahar oil biodiesel. In this case, the B30 blend of Nahar oil biodiesel is taken as base fuel and different proportionate carbon nanotubes blends are compared with pure diesel. The performance analysis is done in a multi-cylinder test engine setup, and the emission of different exhaust gases is considered. The outcomes from the tests demonstrate that Nahar oil biodiesel and its mixes with carbon nanotubes can substitute diesel engines in the future when nonrenewable energy source stores become compromised. [ABSTRACT FROM AUTHOR]

Microalgae are considered to be a promising and prospective source of lipids for the production of biocomponents for conventional liquid fuels. The available sources contain a lot of information about the cultivation of biomass and the amounts and composition of the resulting bio-oils. However, there is a lack of reliable and verified data on the impact of fuel blends based on microalgae biodiesel on the quality of the emitted exhaust gas. Therefore, the main objective of the study was to present the emission characteristics of a compression-ignition engine fuelled with a blend of diesel fuel and biodiesel produced from the lipids accumulated in the biomass of a heterotrophic culture of Schizochytrium sp. The final concentrations of microalgal biomass and lipids in the culture were 140.7 ± 13.9 g/L and 58.2 ± 1.1 g/L, respectively. The composition of fatty acids in the lipid fraction was dominated by decosahexaenoic acid (43.8 ± 2.8%) and palmitic acid (40.4 ± 2.8%). All parameters of the bio-oil met the requirements of the EN 14214 standard. It was found that the use of bio-components allowed lower concentrations of hydrocarbons in the exhaust gas, ranging between 33 ± 2 ppm and 38 ± 7 ppm, depending on the load level of the engine. For smoke opacity, lower emissions were found in the range of 50–100% engine load levels, where the observed content was between 23 ± 4% and 53 ± 8%. [ABSTRACT FROM AUTHOR]

In this study, pollutant gas emissions and combustion efficiency of LPG fuel burning in a steam boiler were investigated experimentally and compared with the diesel fuel-based results. Designed and manufactured of a new tangential swirl burner, and used for gaseous fuel combustion (LPG) in the boiler that was already designed to be operated with liquid fuel (diesel). The study involves conducting experiments using a broad range of equivalence ratios (Φ) and with three different diameter ratios (dr = 1/10, 1/15, and 1/20) (diameter ratios = The variable diameter of the burner is compared against the fixed diameter of the boiler). The volumetric ratios of CO2, CO as well as the HC content in the exhausted gases are measured and the boiler efficiency is predicted. The obtained results revealed that the replacement of the liquid fuel burner with the tangential swirl gas (LPG) burner is simple, inexpensive, and had no negative effect on the other parts of the boiler. In addition, the lowest pollutant gas concentrations detected in the exhausted gases and the highest boiler efficiency are obtained with a diameter ratio of 1/10. In comparison with diesel fuel combustion, the LPG fuel offered the cleanest combustion at Φ approaching 1 and above, required less O2 for complete combustion, and had the least HC content in the exhaust gases at the lean mixing area. Finally, the boiler efficiency operating with LPG fuel was higher than that obtained with diesel fuel for all equivalence ratios. [ABSTRACT FROM AUTHOR]

Biodiesel/n-pentanol blend fuels have been regarded as the attractive alternatives for the utilization of Diesel engines. However, the fundamental studies of low temperature combustion and soot formation characteristics of biodiesel/n-pentanol blend fuels in diesel engines are still scarce. The low temperature combustion and soot emission characteristics of pure waste cooking oil biodiesel (B100) and 70% waste cooking oil biodiesel/30% n-pentanol blend (B70P30) were experimentally studied in an optical engine in the present study. Results reveal that B70P30 has longer ignition delays than B100 at low exhaust gas re-circulation rate, but the ignition delays of B70P30 become similar or even shorter when the exhaust gas re-circulation rate is over 12%. Adding n-pentanol into biodiesel increases the in-cylinder combustion pressure peak and maximum pressure rise rate. In addition, the delay in the appearance of ignition kernels and two-color images are observed for B70P30 fuel. In the initial stage of fuel combustion, B70P30 has less ignition kernels and lower soot KL factor distribution area. In the middle and late stages of combustion, flame area of B70P30 is small and flame brightness is weaker. Also, at the end of combustion, the two-color images of B70P30 show that the soot KL factor distribution around the periphery of the chamber is decreasing at a higher rate compare to B100. [ABSTRACT FROM AUTHOR]

The scientific paper conducted empirical studies related to the effectiveness of the use of dimethyl ether as an additive to diesel fuel and its impact on the efficiency of the mixture creation and combustion process. The measure of the above quality was the observation and parametric assessment of the then generated vibroacoustic processes, the relations of which were assessed using the peak and effective value of vibration accelerations, and also assessment of toxic exhaust gas components. The transformation of the main process into its vibroacoustic and emission representations allowed for the construction of mathematical relations between them, expressed in a specific engine operating space, and a vector of tribological parameters, expressing specific friction changes occurring in the critical kinematic pairs of the combustion and mixture formation area. The tests were carried out on a single-cylinder research engine with direct fuel injection, in stationary conditions with a time-invariant control vector. As part of the procedures, a constant and optimal value of thermodynamic parameters defining the thermal state of the engine was maintained, minimizing external forces and disturbances that could affect the active value of the measurement signal. The research results are empirical vibroacoustic and emission characteristics for various signal domains and their parameterization supplemented with a detailed analysis of the results, developed vibroacoustic and emission mathematical models depending on the operating parameters, type of fuel and combustible mixture formation variables, supplemented with an assessment of their degree of mapping to the dynamic source process. The dimethyl ether application resulted in a emission reduction by the coefficient: 24.3-57.8 (hydrocarbons), 1.03-1.24 (carbon monoxide), and an increase in nitrogen oxides in the range of 1.01-1.08. The use of dimethyl ether as a base fuel component has a positive effect on reducing the peak value of vibration accelerations in the range of 16-28%, and the root mean square in the range of 14-65%. [ABSTRACT FROM AUTHOR]

The object of this study is the process of operation of a diesel engine in a wheeled tractor on methyl ether of spent frying sunflower oil. The task being solved is to improve the environmental performance of a diesel engine in a wheeled tractor during the operation of its diesel on such biodiesel fuel and its mixtures with mineral diesel fuel. The characteristics of the diesel D-243 were determined by the experimental method with the measurement of the toxicity of the waste gases during its operation on the methyl ether of the spent sunflower oil, mineral fuel, and their mixtures. A decrease in the content of soot in diesel exhaust gases and a slight increase in the types of nitrogen oxides was registered. The theoretical method using a mathematical model determined the indicators of a wheeled tractor during its movement with a trailer for the accepted driving cycle and the operation of its diesel on different fuels. To that end, the characteristics of a specific diesel engine were described by polynomial models. The adequacy of the mathematical model of the movement of a tractor with a trailer over a driving cycle was tested. By means of a mathematical model, the total road emissions of harmful substances of a diesel engine were calculated when the tractor is running with a trailer over the accepted driving cycle. Calculations were performed for two types of fuel: mineral diesel fuel and biodiesel fuel. Biofuel consumption increases by almost 10 % compared to diesel fuel. The total emissions of harmful substances are 1.1 times lower in a diesel engine running on biofuel than when using mineral fuel. The results could be used in the operation of technological transport in the industry and agriculture provided there is a sufficient volume of raw materials for the production of biofuel. [ABSTRACT FROM AUTHOR]

This article shows the effect of the addition of effective microorganisms and silver on the exhaust gas composition and fuel consumption. Exhaust emission standards are becoming increasingly stringent, which makes it difficult for engine manufacturers to meet them. For this reason, intensive work is underway to use alternative propulsion systems on ships, and for diesel engines, alternative fuels. Among other things, this applies to mixtures of petroleum-based fuels with vegetable oils and their esters. Unfortunately, their use, due to their physicochemical properties, can negatively affect the performance of the engine and the wear of its components. Therefore, the aim of this study was to see how additives of effective microorganisms in the form of ceramic liquid and tubes, and a silver solution and colloidal silver would affect some engine parameters, including the exhaust gas composition and fuel consumption. The authors are not aware of the results of previous research on this issue. The tests were carried out on a diesel engine for four types of green additives at concentrations of 2% and 5%, at different ranges of its load. The additives added to the diesel fuel were characterised, and the test stand was presented, along with the parameters of the tested fuel. The effect of additives on selected engine parameters, including fuel consumption, was presented. The characteristics of hourly fuel consumption and selected components of the exhaust gas, including nitrogen oxides, carbon monoxide and carbon dioxide as a function of the concentration of ecological additives are shown and analysed. It was found that the most beneficial additive that had a positive effect on the exhaust gas composition and fuel consumption was a silver solution in a 2% concentration. There was a decrease of up to 4% in the NOx content of the exhaust gas, a decrease in carbon monoxide of more than 28%, a decrease in carbon dioxide of 4.6% and a decrease in fuel consumption of around 3% was achieved under the tested conditions. The use of these additives is an innovative solution that has a positive impact on reducing the emissions of harmful compounds into the atmosphere. In further research, it will be necessary to study the effect of this additive on the combustion process in the engine and the wear of its components, as well as to confirm the results obtained in real operating conditions. [ABSTRACT FROM AUTHOR]

The demand for sustainable fuels has driven research on biodiesel blends' combustion characteristics and emissions. The study evaluates the performance of macauba and soybean biodiesel blends by analyzing torque, power, and fuel consumption indicators. The effects of leaf extract additives on engine performance are also assessed. Comparing macauba and soybean blends show similar load, brake power, and engine speed trends on response variables. However, slight variations in coefficients and significance levels indicate unique combustion and emission profiles for each blend. Understanding these distinctions is crucial for optimizing engine performance and emission control strategies. Parameters analyzed include brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), exhaust gas temperature (EGT), carbon monoxide (CO) emissions, hydrocarbon (HC) emissions, oxides of nitrogen (NOx) emissions, smoke opacity, cylinder pressure, heat release rate, and ignition delay. Blends 80% Soy Methyl and 20% Macauba Methyl Biodiesel (BSM20) demonstrates 5–10% superior fuel efficiency, 8–12% higher energy conversion capability, 3–5% lower exhaust temperatures, 10–15% reduced emissions, and 5–8% enhanced efficiency versus other blends and Diesel. It also shows 10–20% lower hydrocarbon and CO emissions, 15–25% reduced NOx, 20–30% lower particulate matter, and more efficient energy release during combustion. Optimizing heat release rate and ignition delay is crucial; BSM20 shows a 10–15% shorter ignition delay. Understanding blend distinctions is key for optimizing performance and emissions. BSM20 blend demonstrates superior fuel efficiency, energy conversion capability, lower exhaust gas temperatures, reduced emissions, and enhanced engine efficiency compared to other blends and Diesel. It also shows lower hydrocarbon, CO, and NOx emissions, reduced particulate matter emissions, and more efficient energy release during combustion. Optimizing heat release rate and ignition delay is crucial for cleaner combustion and improved engine performance. [ABSTRACT FROM AUTHOR]

The primary cause of global warming and human respiratory problems is the impact of engine emissions from fuel combustion. The mitigation procedure for these pollutants involves altering the design of engine components or using alternative fuel sources. To effectively use biofuel, one must focus on minimizing engine emissions and addressing the issue of fuel shortages. This work specifically examined the impact of using novel forms of biodiesel derived from dill oil on the performance and emissions of CI engine. Blends of conventional Iraqi diesel fuel and dill oil biodiesel were created and mixed in volumetric proportions of 10%, 20%, 40%, 60%, 80%, and 100%. A compression ratio of 18 and a fuel injection timing of 23° bTDC were the settings used for the test engine. The testing findings reveal that this particular biodiesel enhances brake-specific fuel consumption (BSFC), themass of fuel burnt rate, and exhaust gas temperature (EGT), while decreasing engine thermal efficiency (BTHE), delay period time (DP), and cylinder pressure (ICP). Also, it decreased emissions of HC, soot, and CO, but increased emissions of CO2 and NOx. [ABSTRACT FROM AUTHOR]

The International Maritime Organization (IMO) has set targets to reduce carbon emissions from shipping by 40% by 2030 (IMO2030) and 70% by 2040 (IMO2050). Within the framework of decarbonising the shipping industry, liquefied natural gas (LNG) fuel and carbon capture technologies are envisioned as a transitional option toward a pathway for clean energy fuels. The aim of the complex experimental and computational studies performed was to evaluate the CO2 capture potential through the utilisation of LNG cold potential on the FSR-type vessel within a dual-fuel propulsion system. Based on the experimental studies focused on actual FSRU-type vessel performance, the energy efficiency indicators of the heat exchanging machinery were determined to fluctuate at a 0.78–0.99 ratio. The data obtained were used to perform an algorithm-based systematic comparison of energy balances between LNG regasification and fuel combustion cycles on an FSRU-type vessel. In the due course of research, it was determined that LNG fuel combustion requires 18,254 kJ/kg energy to separate and capture CO2 in the liquid phase to form exhaust gas; meanwhile, low sulfur marine diesel oil (LSMDO) requires 13,889 kJ/kg of energy. According to the performed calculations, the regasification of 1 kg LNG requires 1018 kJ/kg energy, achieving a cryogenic carbon capture ratio of 5–6% using LNG as a fuel and 7–8% using LSMDO as a fuel. The field of carbon capture in the maritime industry is currently in its pioneering stage, and the results achieved through research establish an informative foundation that is crucial for the constructive development and practical implementation of cryogenic carbon capture technology on dual-fuel ships. [ABSTRACT FROM AUTHOR]

The results of an experimental study of nitrogen oxide (NO) and particulate matter (PM) concentrations in the exhaust gas of a compression-ignition engine used in agricultural tractors and other commercial vehicles are presented. The engine was fueled with second-generation biodiesel obtained from used frying oils (classified as waste) and first-generation biodiesel produced from rapeseed oil as well as, comparatively, diesel fuel. Tests were conducted on a dynamometer bench at a variable load and a variable engine speed. The levels of PM and NO emissions in the exhaust gas were determined. The study showed significant environmental benefits of using first- and second-generation biodiesel to power the engine due to the level of PM emissions. The PM content, when burning ester biofuel compared to diesel fuel, was reduced by 45–70% on average under the speed and load conditions implemented. As for the concentration of nitrogen oxide in the exhaust gas, no clear trend of change was shown for the biodiesel in relation to the diesel fuel. The level of NO emissions in the range of full-power characteristics was found to be lower for both tested biofuels compared to diesel fuel at lower engine speeds by an average of 7–8%, while in the range of a higher rotation speed, the NO content in the exhaust gases was higher for the tested biofuels compared to diesel oil by an average of 4–5%. The realized engine performance tests, moreover, showed an unfavorable effect of the biodiesel on the engine energy parameters. In the case of biofuels, this was by more than 4% compared to diesel fuel. [ABSTRACT FROM AUTHOR]

The present work emphasized overall viability study of using waste transformer oil (WTO) and its combinations on a diesel engine. To accomplish this fuel samples were divided into three sets with different volumetric proportions. Each set of fuel is compared with the others and finally, the reference fuel is regular diesel. After thorough characterization and utilizing spectroscopic methods like CHNS analysis and FTIR, the performance and emission evaluation was done on a one-cylinder diesel engine. It has been discovered that the flash point, calorific value, and viscosity of WTO blends are more than regular diesel fuel. The WTO blends have higher carbon content than diesel but higher Sulphur content than diesel fuel. WTO and its blends have some similar functional groups as diesel fuel. According to the performance and emission evaluation, the diesel engine is capable of operating even when fueled with raw WTO. Among all the samples tested, WTO20 BD10D70 shows the most satisfactory result. The brake thermal efficiency of WTO20BD10D70 was almost similar to diesel fuel, while BSFC and BSEC were found to be only 4.73% and 3.46% higher than diesel fuel, respectively. The exhaust gas temperature was 8% lower than diesel. However, HC emission of WTO20BD10D70 was 20% more than diesel fuel, while CO and NOx emissions were 14% and 4.75% lower than diesel fuel. So, the sample code with WTO20BD10D70 can be recommended as a substitute for regular diesel fuel. [ABSTRACT FROM AUTHOR]

This article discusses the potential applications of the Fuel Shot liquid catalyst in compression ignition (CI) engines for reducing toxic substances in exhaust gases. Incorporating catalysts into fuel can optimize the combustion process, consequently reducing the emission of toxic substances into the atmosphere. Toxic compounds, such as nitrogen oxides, particulate matter, and hydrocarbons, adversely affect flora and fauna. Various methods are known for reducing their concentration in engine exhaust gases, one of which is the Fuel Shot liquid catalyst. The authors conducted experiments on a Fiat 1.3 JTD engine with a Common Rail system. The results indicate that the application of the liquid catalyst reduces the content of nitrogen oxides and hydrocarbons in the exhaust gases and slightly decreases fuel consumption. Additionally, investigations were carried out on the engine's injection apparatus, which was fueled with modified fuel. The findings demonstrate that the fuel additive does not affect the wear of precision parts of fuel injectors and high-pressure pumps. [ABSTRACT FROM AUTHOR]

Nowadays, researchers are very interested in improving the stability and solubility of blending diesel fuel with a high percentage of ethanol. As a result, the goal of this paper was to find a way to use the surfactant of Tri-n-butyl phosphate (TBP) substance to blend ethanol with diesel fuel to a level of 40%. Diesel fuel is mixed with ethanol in volumetric proportions of 10%, 20%, 30%, and 40%, as well as a tiny amount of TBP from 1 to 4%. The prepared blends were the subject of an experiment evaluation by fueling a direct injection diesel engine. This engine is a water-cooled, commercial diesel engine, single cylinder, and four-stroke with 12 kW maximum power. The four blends were evaluated as clean fuel mixtures of 10% ethanol/90% diesel/1% TBP, 20% ethanol/80% diesel/2% TBP, 30% ethanol/70% diesel/3% TBP, and 40% ethanol/60% diesel/4% TBP. As the starting fuel, we used 100% diesel to compare the results. The engine's output and emissions have been measured at various engine loads and constant speeds of 1500 rpm. According to the data gathered, even when the percentage of ethanol was increased to 40%, neither the base fuel nor the engine BTE changed significantly. The engine exhaust gas temperature was found to decrease slightly when the proportion of ethanol was increased. When bioethanol is increased to 40% of the base volume, it causes an increase in the combustion of unburned hydrocarbons and CO emissions. However, when the percentage of ethanol was increased from 100% diesel to the base fuel to 40%, CO2 emissions decreased, and O2 emissions slightly increased. [ABSTRACT FROM AUTHOR]

To accelerate the energy transition, starting February 1, 2023, the Indonesian government has made it mandatory to use biodiesel (B35). Biodiesel has different characteristics from diesel oil, especially its greater viscosity and density, lower heating value, and high NOx emission. Therefore, this research has been carried out by adding the additive diethyl ether (DEE) to B35 to reduce the viscosity and density, increase the cetane number, and reduce emissions. The effects of diethyl ether on engine performances have been evaluated, including parameters of torque, power, brake thermal efficiency, brake-specific fuel consumption, exhaust emissions, and lubricants. The fuels used are B35 (35% FAME palm oil + 65% diesel oil), and B35 + DEE, with a DEE volume percentage of 3% to 6%. Diesel fuel (B0) was used as a comparison. Tests were carried out in the engine performance test laboratory using the heavy-duty diesel engine Komatsu SAA12V140E-3 at various engine speeds. The test results showed that adding diethyl ether slightly increases the average maximum power, increases brake thermal efficiency, and reduces brake-specific fuel consumption and emissions compared to B35. Very significant effects were seen in NOx and SO2 exhaust emissions. At maximum load, the mixture with 4% diethyl ether gave the greatest brake thermal efficiency, the lowest brake-specific fuel consumption, and the greatest reduction in NOx and SO2 emissions, respectively 7.69%, 6.30%, 53.48%, and 40.89% compared to B35, and 2.24%, (-0.90%), 48.88% and 71.17% compared to B0, respectively. Evaluation of lubricating oil during the performance test did not show a significant difference for all types of fuel used. [ABSTRACT FROM AUTHOR]

The extensive use of traditional fossil fuels has exacerbated crises such as environmental pollution, depletion of non renewable energy and global greenhouse effect. Ammonia (NH 3) is considered a promising fuel to replace conventional fossil energy in internal combustion engines. A four-cylinder, four-stroke commercial diesel generator (HTD-20GF) was modified and two different ammonia fuel injection systems, premixed charge compression ignition (PCCI) combustion and gas phase port injection (GPPI), were developed. The exhaust emission characteristics, thermal efficiency and ammonia energy ratio of ammonia/diesel dual fuel (ADDF) generator in both PCCI and GPPI modes were studied. The experimental results showed that the overall NO emission in GPPI mode was lower than that in PCCI mode. From the experimental results, both PCCI and GPPI mode can reduce CO 2 emission. The GPPI mode was significantly more effective than the PCCI mode in reducing the volume fraction of CO 2 in the exhaust gas. Compared with all diesel mode, the HC content in the exhaust gas got worse at lower ammonia energy ratio in both modes, but the increase rate of HC emissions slightly improved as the ammonia energy ratio increased. However, PCCI and GPPI modes reduced the thermal efficiency of the generator, and ammonia had a more negative effect on the thermal efficiency of the ADDF generator in PCCI mode.The experimental results also tested the limiting ammonia energy ratio of this commercial generator at 1 kW. In summary, this study provides a new perspective on the different feeding methods of ammonia as a fuel, which may contribute to the selection of fuel injection methods for ammonia engines to decrease emissions. [ABSTRACT FROM AUTHOR]

This research study aims to investigate the causes of the particles emitted by a spark ignition engine fueled with hydrogen. The experiments were carried out on a single cylinder 250 cm3 direct injection spark ignition engine. Two operating conditions at 2000 rpm both full and low load, representative of typical urban conditions, were investigated. A physical characterization of the particles, size and number, was performed through an Engine Exhaust Particle Sizer coupled to a single diluter. Chemical characterization was carried out on the condensed exhaust. The simultaneous analysis of the physical properties and their chemical characterization allows to point out not only the role of the oil on the particle emissions but also to give an important information on its state/composition, if it was unburned and oxidized. Particles were detected with conventional spectrometer at low load while at high load the noise signal ratio is too high to distinguish the presence of particles. More detailed chemical techniques highlighted the presence of PAH, alkyl-PAHs, oxy-PAHs and unburned hydrocarbon in the exhaust due to the mineral oil. [Display omitted] • Engine performance and pollutant emissions were measured for a DI SI engine fueled with hydrogen. • Effect of lube oil on particle number and size at exhaust of a hydrogen fueled engine. • Presence of PAH, alkyl-PAHs, oxy-PAHs and mineral oil in the exhausts. • A part of the lubricating oil passed into the combustion chamber and underwent thermal degradation. • Emitted oil presented a good affinity with water thus evidencing its impact also on the water and soil pollution. [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]

The aim of the study was to determine impact of commercially available hydrotreated vegetable oil (HVO) and its mixture (HVO5, where 5% (v/v) HVO and 95% (v/v) FDD) with diesel fuel (FDD) on the power, torque, fuel consumption, and exhaust gas composition of an atmospheric internal combustion diesel engine used in off-road applications. Diesel fuel was used as the comparative fuel. Testing was realized in a full-load mode on the KOHLER KDI 1903 M 3-cylinder diesel engine on a SIERRA CP-Engineering engine test bench. The AVL SESAM FTIR exhaust gas analytical system was used to determine exhaust gas emissions, while the AVL KMA Mobile fuel consumption measuring device was used to measure fuel consumption. Research showed that the lowest power and torque readings were obtained with FDD, while HVO showed a slightly higher result compared to the fossil diesel fuel. At the same time, the highest hourly fuel consumption was observed running on HVO5, while the lowest was observed with FDD. Increases in carbon monoxide (CO), carbon dioxide (CO2), and nitrogen oxide (NOx) emissions were observed for HVO5 compared to those of FDD. The CO content in emissions increased by an average of 3.0% using HVO and by an average of 36% using HVO5, but the NOx content in the emissions increased by an average of 3.0% using HVO and by an average of 8.8% using HVO5. The reduction by an average of 60% using HVO in emissions was found in the case of hydrocarbons (HC). Research confirmed that the physicochemical properties of HVO could leave an impact on the main engine performance parameters and exhaust emissions. [ABSTRACT FROM AUTHOR]

The engine combustion products were measured and analyzed based on emissions of exhaust. Due to the utilization of a variety of fuels, such as petroleum diesel and bio-diesel in diesel- generated engines, they emit pollution-insecure emissions. To explore this emission quantity, a numbers of experiments were conducted utilizing a single-cylinder engine, Land Curser six-cylinder, Mazda WL31 engine mechanical biodiesel vehicle and In-Line engine. The performance research was given for the data acquired from the Mazda WL31 four-cylinder engine. Landcom III gas analyzer was used to sense and record the exhaust gas emissions from the burning of diesel fuel, which was utilized for data analysis. Various gas discharges and their constituents were independently analyzed. The results of the test show that the harmful emissions of biodiesel fuel are much lower than the emissions of fuel made from mineral oil. [ABSTRACT FROM AUTHOR]

The proposed changes to the legislation on diesel cars require intensification of work on the possibilities of reducing emissions of harmful substances into the atmosphere by these vehicles. The subject of experimental research included in the manuscript was the Skoda Octavia with a 1.9 TDI (turbocharged direct injection) compression ignition engine (type 1Z). Light absorption measurements of smokiness of the exhaust gases emitted after combustion of various biofuels (conventional diesel, pure hydrotreated vegetable oil, hydrotreated vegetable oil, biobutanol) and their blends with fossil diesel fuel were studied. The measured light absorption coefficient is the reciprocal of the thickness of the layer, after passing through which the light has a ten times lower intensity. Its unit is the reciprocal of the meter (1/m or m−1). The results obtained by means of a standard smokiness meter indicate that the use of biofuels or their blends, in general, reduces smoke formation. [ABSTRACT FROM AUTHOR]

This study successfully investigated the engine performance and emission characteristics of a dual injection system that uses both gasoline and ethanol fuels. The study utilized a microcontroller-based control system (PGM-FI) to substitute ethanol fuel injection for gasoline injection. Ethanol fuel was injected at the inlet with three different pressures: 1.0 bar, 1.2 bar, and 1.4 bar, while gasoline injector pressure was fixed at 2 bar. Results showed that substituting ethanol injection with a pressure of 1 bar resulted in a slight decrease in torque and power, but it was the best compared to the other pressures tested. The study found that the use of ethanol injection resulted in improved fuel economy at an ethanol injector pressure of 1 bar with a reduction in SFC of 8.89%. Exhaust emissions were also reduced, with a maximum reduction in CO emissions of 42.54% occurring at a pressure of 1 bar. Similarly, the lowest HC content in exhaust gas was observed at a pressure of 1 bar, which was reduced by 44.48%. However, the results highlighted that ethanol injection pressure could significantly reduce fuel consumption for case A-04 and increase the air-fuel ratio. [ABSTRACT FROM AUTHOR]

This paper presents quantitative comparison of the effect of modified contemporary diesel blends under effective parameters of diesel engine. Comparative tests were made under bench conditions. The values of the power, economy and toxic performance of a diesel engine operating with standard fuel and modified diesel blends have been determined. It is concluded that the operation of a Volkswagen 1.9 diesel engine with a modified contemporary diesel blend results in a reduction in the exhaust gas temperature without altering its economic and environmental performance. [ABSTRACT FROM AUTHOR]

• A sensor system is developed for simultaneous measurement of SO 2 and CO 2 using mid-infrared laser absorption spectroscopy. • An enhanced broadband concentration inversion method increases detection accuracy by an average of 30.76%. • Dynamic response, accuracy, sensitivity, and detection limit are evaluated in the laboratory. • Diesel sulfur content detection was simulated by field experiments. Simultaneous measurement of CO 2 and SO 2 in ship exhaust gases is a common method for assessing compliance with sulfur emission standards. This study develops a new ship exhaust gas analyzer using time-division multiplexing of two quantum cascade lasers for simultaneous detection of the two gas species. A digital circuit integrated with a dual-channel waveform generator and a lock-in amplifier is developed to implement wavelength modulation spectroscopy (WMS) scheme. To enhance the measurement accuracy of SO 2 with broadband absorption feature, a novel WMS approach that combines first-harmonic and normalized second-harmonic detection is introduced. A Kalman filter algorithm is employed to further refine the measurement precision. Experimental results show a 30.76% increase in detection accuracy. With a 1 s time resolution, the sensitivities of 13.4 ppb for SO 2 and 9.81 ppm for CO 2 are achieved. The effectiveness of the prototype for sulfur content detection is demonstrated, aiding emission management of water transport emissions. [ABSTRACT FROM AUTHOR]

This study investigates cancer-related mutations (TA98 and YG5185 strains/Ames test), cell death (human A549 cell line/MTT assay) and unregulated pollutants (16 PAH, 13 carbonyls) from the gas exhaust emissions from a last-mile delivery vehicle following the WLTC driving cycle, operating with hydrotreated vegetable oil and biodiesel. Both biofuels were used pure and blended 20 % by volume with diesel fuel. Gas phase samples were collected using XAD-2 Amberlite® resin. Total carbonyl emission factors for the different fuels ranged from 9.4 ± 0.4 (HVO100) to 14.8 ± 1.6 mg/km (B20), while PAH emission factors ranged from 1.8 ± 0.5 (B100) to 4.3 ± 0.9 mg/km (HVO20). The ester group in biodiesel demonstrated a significant impact on increasing carbonyl emissions. All fuels were cytotoxic at the highest concentration of exhaust gases, causing more than 30 % cell death in human cell line A549 (HVO100 ≈ HVO20 > B100 ≈ B20 > ULSD). No significant correlation was found between cytotoxicity and most of PAH and carbonyls. A strong correlation between PAH and mutagenicity (Pearson correlation coefficient higher than 0.6 for PAH with 3 or more rings) was observed with strain YG5185, particularly when using the metabolic activator. These results indicate that the exhaust gases from the tested biofuels pose potential health risks, particularly in chronic exposure scenarios. [Display omitted] • Unregulated gas emissions of last-mile delivery truck under WLTC driving cycle. • Tests conducted with drop-in near-zero carbon footprint biodiesel and HVO fuels. • No correlation between fuels aromatic content and carbonyl emissions. • No significant correlation between cytotoxicity and most of PAH and carbonyls. • PAH-sensitive strain YG5185 successful to correlate PAH, aldehydes and mutagenicity. [ABSTRACT FROM AUTHOR]

Ammonia is one of the most widely used carbon-neutral fuels; therefore, many efforts have been made to supply ammonia to dual fuel (DF) marine engines. Because ammonia is toxic, the amount of unburned ammonia in exhaust gas should be reduced. However, as ammonia does not easily combust, it is necessary to oxidize the unburned substances in the latter part of the main combustion process. Thus, diesel post-injection is required to oxidize the unburned emissions. In this study, the effects of diesel post-injection timing and amount on the combustion, emissions, and efficiency of ammonia-diesel DF four-stroke 12-L single-cylinder marine engine were experimentally evaluated under 900 rpm and 50 % load conditions. Post-injection timing varied from 35° to 95° after the start of a micro pilot (MP). The amount of post-injection was maintained at 25 % and 40 % of total injected diesel fuel. Consequently, conducting a diesel post-injection at a level of 40 % close to the MP injection enabled the reduction of unburned hydrocarbon by 18.9 %, unburned ammonia by 11.2 % and N₂O—a major greenhouse gas—by 19.4 % compared to conventional dual-fuel combustion while maintaining equivalent thermal efficiency. • Diesel post-injection reduced NO, N₂O, and unburned ammonia emissions by 16.1 %, 19.4 %, and 11.2 %. • Post-injection at 40 % ratio and 35° after MP timing maintained thermal efficiency equivalent to neat diesel. • Ammonia-diesel DF combustion showed faster initial combustion but shorter MFB50-90 durations. • Diesel post-injection increased CO₂ emissions but reduced NO emissions compared to neat diesel. [ABSTRACT FROM AUTHOR]

In recent years, the interest in renewable fuels has increased mainly due to regulations regulating the permissible limits of toxic components of exhaust gases emitted by reciprocating engines. This paper presents the results of a comparison of the effects of fueling a compression-ignition piston engine with a mixture of diesel fuel and n-butanol, as well as RME (Rapeseed Oil Methyl Esters) biodiesel and n-butanol. The tests were carried out for a constant load and a wide energetic share of fuels in the mixture. The main focus was on the assessment of combustion stability, the uniqueness of the combustion stages, and the assessment of the fuel type influence on the CA50 angle. The tests show that RME offers the possibility of efficient combustion with n-butanol with up to 80% energy share. The share of n-butanol has a positive effect on the engine's efficiency and very effectively reduces soot emissions. Without the influence on COVIMEP, the share of n-butanol up to 40% in the mixture with diesel fuel and up to 80% in the mixture with RME was recorded. Combustion of RME with n-butanol was more stable. The share of n-butanol in the mixture with diesel fuel caused an increase in NOx emissions, and co-combustion with RME caused a decrease in emissions. [ABSTRACT FROM AUTHOR]

[Display omitted] The fast depletion of the petroleum reserves and the rising environmental threats have created an urgent need for sustainable-alternate fuels for the transport and agricultural sectors. In this regard, the ternary blends (diesel–biodiesel-alcohol) have the potential to address the above concerns as they offer huge potential in mitigating exhaust emissions and enhancing engine performance. In the present work, jatropha biodiesel and heptanol have been used as oxygenated additives in the ternary blends in order to save considerable quanta of diesel fuel by restricting its volumetric content to only 40 %. In addition, the fuel injection pressure (IP) is a vital factor that determines the performance and emissions of CI (Compression Ignition) engines. The impact of variations of IP on the performance and emission of CI engine fuelled with ternary blends needs fresh investigation. The previous works lack the analysis of high IP variation in diesel engine fuelled with ternary blend that involve higher alcohol. This experimental work aims to investigate the improvement in CI engine performance and reduction in the exhaust emissions by applying varied IP to the engine powered with diesel-jatropha biodiesel-heptanol blends. In this context, four different ternary blends were prepared by varying biodiesel and heptanol contents from 20 to 50 % and 10–40 %, respectively. The ternary blends were tested in a single-cylinder, four-stroke, direct-injection CI engine by varying the IP from 400 to 500 bar at 10 and 20 Nm engine loads while maintaining the engine speed at 1800 rpm. The results indicated that DBOHep20 achieved a maximum reduction of CO and smoke emissions by 57.4 % and 91.6 %, respectively. The lowest NO x emission was achieved by DBHep40 which was found to be 13.27 % lower than diesel. In the case of engine performance, DBHep40 resulted in lowest BSFC and highest BTE which were found to be just 12.5 % higher and 3.9 % lower than diesel, respectively. The lower IP leads to lesser emissions with a slight compromise with engine performance. [ABSTRACT FROM AUTHOR]

Renewable energy is getting more attention in recent times due to the rapid depletion of fossil fuel reserves. Production and consumption of biofuels derived from biomass has significantly increased. In the present work, Spirulina microalgae have been chosen as feedstock for biodiesel production. Diesel and biodiesel were mixed in different volumetric ratios to prepare fuel blends (SBF0, SBF20, SBF40, SBF60, SBF80, and SBF100). Energy and exergy analysis has been performed on a four-stroke, single-cylinder diesel engine. Experimentation was done under varying loads at 1500 RPM. The effect of multiple loads and blends was investigated for brake power (BP), cooling water losses (Qw), exhaust gas losses (Qexh), and unaccounted losses (Qun). Pure diesel SBF100 has the highest and lowest exergy efficiencies, respectively equaling roughly 31.65% and 29.75%. It has been observed that BP and Qw increase with the increase in load whereas Qexh and Qun show a decreasing trend. It was also observed that with an increase in blending, Qw increases while Qexh decreases. In the exergy analysis, it was observed that the exergy destruction rate has a maximum fraction of input exergy values of 46.01% and 46.29% for Diesel and SBF20 respectively. The system engine sustainability index was in the range of 1.27 to 1.46, which is directly related to exergy efficiencies. [ABSTRACT FROM AUTHOR]

Out of various strategies to extenuate the diesel engine emissions, use of water-blended diesel fuel in emulsified form is found to be a prominent option. The studies carried out by various researchers give quite inconsistent results for optimum water concentration, surfactant concentration, and HLB value. An effort has been made in this paper to analyze this inconsistency of water concentration and surfactant for engine emissions and performance along with the effect of compression ratio. The work has been carried out on a non-road, constant rpm, VCR (variable compression ratio) diesel engine. Different emulsions of 5%, 10%, 15%, and 20% water-in-diesel with 3% emulsifier concentration were tested on the diesel-optimized engine at CR 21. The results showed that emulsion of 15% water-in-diesel is optimal on the basis of emissions and performance. Further, the selected 15% emulsion is tested with 4% emulsifier concentration. It improved the stability of emulsion and performance of the engine with slight adverse effects on the NOx emissions. Then, emulsion with 4% surfactant and 15% water is tested to determine optimum compression ratio for emulsified fuels. CR 20 is found in optimum. Remarkably 9.28% improvement in BTE is observed reaching up to 23.89% as compared to 21.86% with bare diesel. 25.1% reduction in NOx and more than 50% reduction in smoke is observed. Overall, it is concluded that the water-blended diesel emulsion could serve as a fuel-efficient cleaner combustion technology and needs to be standardized. Abbreviations HLB: Hydrophile–Lipophile Balance; Cv: Calorific Value; W/D: Water in Diesel; PM: Particulate matter; RPM: Rotation per minute; HC: Hydrocarbon; CR: Compression Ratio; EGT: Exhaust Gas Temperature; BTE: Brake Thermal Efficiency; NOx: Oxides of Nitrogen; BSFC: Brake specific fuel consumption [ABSTRACT FROM AUTHOR]

Many scientists have utilized acetylene as a renewable fuel in the dual-fuel engine without considering the significance of induction length. This paper aims to study and analyze the effect of induction length for acetylene fueled CI engine. In this present study, the author has conducted an experimental investigation on a modified diesel engine in which acetylene is being inducted at different induction length of 25 cm, 50 cm, 75 cm and 100 cm away from the cylinder head. The results show that when acetylene is introduced with a constant flow rate of 1 LPM at 50 cm induction length, BTE is marginally lesser than neat diesel by 0.8%. BSEC increases during acetylene induction under lower loads due to the higher flame velocity of acetylene and minimum value i.e. 10.8 MJ/kWh is observed at full load when induction length is 50 cm for DFE. EGT is slightly lower than diesel for entire loading conditions for acetylene DFE. From the several trials which were conducted, the highest obtained value of peak cylinder pressure is 77.34 bar and the HRR is 51.9 J/°CA when the fuel is inducted at 50 cm. Moreover, CO value is 0.0087%, and HC is 0.024 g/kWh for 50 cm induction length, which is also lower than baseline diesel at full load. However, there is a slight increase in oxides of nitrogen at peak loads, which may be due to the higher combustion temperature. Overall, it can be concluded that the optimum length for acetylene induction is 50 cm. Abbreviation: BMEP: Brake Mean Effective Pressure; BP: Brake Power; BTE: Brake Thermal Efficiency; BSEC: Brake Specific Energy Consumption; CA: Crank Angle; CI: Compression-Ignition; CO: Carbon mono oxide; CV: Calorific Value; DFE: Dual Fuel Engine; DI: Direct Injection; EGT: Exhaust Gas Temperature; HC: Hydrocarbon; IC : Internal Combustion; ID: Ignition Delay; LPM: Liters Per Minute; NOx: Oxides of Nitrogen [ABSTRACT FROM AUTHOR]

A significant amount of waste cooking oil (WCO) remains in the food preparation process worldwide on a daily basis, which can cause environmental pollution if disposed of improperly. The cheapest and effective way to dispose of WCO is by blending it with diesel fuel. In this study three various blends of WCO and diesel fuel were prepared with a WCO proportion of 10%, 20% and 30% and properties were evaluated and compared with petroleum diesel fuel. The density and dynamic viscosity of the blend increase with the increase in WCO content, while the heating value decreases. The blends were then tested in tractor direct injection diesel engine to determine the effect of blending WCO with diesel fuel on the engine performances (power, torque and fuel consumption) and exhaust gases emission (CO, CO2, HC and NOx). The results show that the engine performances using WCO blends are comparable to petroleum diesel fuel and a blend with 30% WCO (B30) achieved the best results among the fuel blends. There were no significant differences in average engine power, torque and fuel consumption per hour between petroleum diesel fuel and B30 blend, while significantly lower (P0.05) average specific fuel consumption were achieved using diesel fuel. The significantly lower (P0.05) average CO and CO2 emissions and significantly higher (P0.05) average HC emission was achieved using diesel fuel compared to B30 blend. No significant difference in average NOx emission was observed between diesel fuel and B30 blend. [ABSTRACT FROM AUTHOR]

The constant development of civilization increases environmental pollution as a result of industrial activity and transport. Consequently, human activity in this area is restricted by regulations governing the permissible emission of harmful substance components into the environment. These include substances emitted by combustion engines, the use of which remains high in many industries. Consequently, research is being conducted to reduce the emissions of harmful exhaust components from existing and newly manufactured internal combustion engines. This research presents a used semi-truck engine, in which an innovative Compressed Natural Gas (CNG) supply system was applied. Using this fuel supply installation allows a mass exchange of the base diesel fuel to natural gas of up to 90%. The study evaluated the effect of the diesel/CNG exchange ratio for different engine operating conditions (engine load, speed) on the concentration of toxic components, such as CO, NO, NO2, NOX, as a sum of NO, NO2, CH4, C2H4, C2H6, C3H8, NH3, and CH2O. The use of a dual-fuel system had a positive effect on the emissions of some harmful exhaust components, even in an engine from a vehicle that had been running for many years on diesel and at high mileage, but, simultaneously, the emissions of some harmful exhaust gas components increased. [ABSTRACT FROM AUTHOR]

This research article presents a comparative experimental study on the performance, exhaust emission and combustion characteristics of a CI engine fuelled with neat diesel and with three kinds of blends viz. MD10 (neat diesel with 10% mosambi peel pyro oil), MDM10 (neat diesel with 10% mosambi peel pyro oil and 10% methanol), MD10+Rh2O3 (neat diesel with 10% mosambi peel pyro oil & nano rhodium oxide fuel additive). The experiments were conducted on a direct injection single-cylinder water-cooled four-stroke diesel engine operated at a constant engine speed of 1500 rpm and under varied brake power conditions. The results showed that MD10+Rh2O3 outperformed the rest in terms of all the performance, emission and combustion characteristics. MD10+Rh2O3 was found to have achieved, 5% higher brake thermal efficiency, 18.5% reduced SFC and 8% reduced exhaust gas temperatures respectively. This fuel has also achieved 10.5%, 5.5%, 9.45%, 11% marginal drop in noxious pollutants such as CO (Carbon Monoxide), unburnt HC (Hydrocarbons), NOx and smoke respectively. Cylinder peak pressures, heat release rate, ignition delay and combustion duration of MD10+ Rh2O3 are recorded to be considerably improved. Thus, using the nanoparticle added mosambi peels pyro oil (NMPPO) blended with diesel as an alternative fuel could impart an eco-friendly, efficient and improved engine operation. [ABSTRACT FROM AUTHOR]

The article describes the methodology of engine tests on new types of low-sulphur marine fuels in laboratory conditions in order to conduct a comprehensive assessment of their suitability for powering full-size marine engines. The innovativeness of the proposed solution consists of adapting the laboratory Diesel Engine Test Bed to carry out experimental tests using residual and alternative fuels so that it is possible to imitate the real operating conditions of the ship engine. The main aim of the research program was to assess the energy efficiency of six different low-sulphur marine fuels and their impact on the chemical emissivity of engine exhaust gases and air pollution with toxic and harmful chemical compounds. In order to achieve the research purpose formulated in this way, it was necessary to: (1) equip the constructed laboratory stand with highly specialised measuring equipment and (2) develop a technology for determining diagnostic parameters representing the basis for developing a ranking of the energy and emission quality of the tested marine fuels according to the proposed physical model. The model distinguishes 10 diagnostic parameters that, after normalisation, form two subsets of evaluation parameters - stimulant and destimulant. Determining their values made it possible to estimate a synthetic variable, according to which all the tested fuels were adjusted in the order from the "best" to the "worst", in accordance with the adopted qualitative criteria of such an assessment. The results of the laboratory tests show that among the considered fuels, i.e., MDO, MGO, RMD 80/L, RMD 80/S, RME 180, and RMG 380 type, the best solution is to use MDO distillate fuel to power full-size marine engines. However, taking into account its high purchase price, a rational alternative decision is to choose RMG 380 type residual fuel, which ranks second in the ranking of the functional quality of the tested marine fuels. [ABSTRACT FROM AUTHOR]

The advancement of modern injection systems of diesel engines is related to a constant increase in the injection pressures generated by injection pumps. This translates into an improvement of the engine operation indexes, including the emission-related ones. Such an approach brings a series of problems related to the design, construction and durability of the injection system. Therefore, the authors asked whether the current market trend in injection systems is the only appropriate path to be taken. When searching for the answer, the authors decided to propose an innovative concept consisting of dissolving exhaust gas in diesel fuel with the use of an injection pump. Such a saturated solution, when flowing out of the injection nozzle, begins the process of releasing the gas dissolved in the fuel. This has a positive impact on the atomization process, hence the process of combustion. The aim of this paper stems from the previously performed research. Due to the nature of the phenomenon, it was necessary to propose a new design for the injection pump. For correct selection of the dimensions of the pumping section, it was of key importance to determine the coefficient of solubility and the bulk modulus of the solution of diesel fuel and exhaust gas. Aside from the description of the applied method and the results of the direct measurements, this paper presents the yet undescribed results of the measurements of the coefficient of solubility of different concentrations of exhaust gas in diesel fuel. The authors also investigated the influence of the amount of exhaust gas dissolved in the fuel on the bulk modulus of the solution. The final part of the paper is a description of a proprietary design of a hypocycloidal injection pump. The application of the innovative drive allows a correct dissolution of exhaust gas in the fuel. [ABSTRACT FROM AUTHOR]

Most research studies have focused on reducing NOx emitted from diesel engines by adding oxygenated fuels (such as alcohol and biodiesel) to diesel to prepare a good alternative to conventional diesel fuels. Biofuels produced from vegetable oil and waste cooking oil while alcohol can be produced from sugarcane and corn. In the current study, the biodiesel used in the tests was derived from waste cooking oil. In this study, the influence of adding Exhaust Gas Recirculation (EGR) to diesel, biodiesel (D80B20), diesel-pentanol (D85PEN15), diesel octanol (D90OCT10), diesel-propanol (D95PRO5) and diesel-biodiesel-pentanol (D50B40PEN10) blends on performance and emitted pollutants of a diesel engine was investigated. The practical experiments were divided into two parts, the first section comparing the results of using diesel and other fuels at different speeds 2100, 2400, 2700 and 3000 rpm at constant loads without EGR. The second section studied the effect of adding EGR in variable proportions (5 %, 10 %, 15 % and 20 %) to the studied fuel mixtures at constant loads and speed. The results showed that adding biodiesel to diesel (without EGR) increases brake specific fuel consumption, NOx and CO2 emissions by 13.66 %, 41.35 % and 30.49 %, respectively, but, the thermal efficiency of the brakes, exhaust gas temperatures, UHC and CO decreases at rates of 12.58 %, 10.22 %, 18.9 % and 21.31 %, respectively, compared to diesel. When EGR was added at 20 %, the maximum increase for D80B20, D95PRO5, ED100, and D85PENT15 was: 18.38 %, 24.60 %, 45.84 %, and 20 %, respectively, compared to when no EGR was added. The thermal efficiency, exhaust gases temperature and NOx levels decreased when EGR rate was raised. [ABSTRACT FROM AUTHOR]

The object of research is the process of lubrication of marine trunk diesel engines. The subject of research is marine diesel engine oils, which provide lubrication, cooling and separation of friction surfaces. The analysis of the operation of marine diesel engines using motor oils with different structural characteristics is carried out. The studies are carried out on Yanmar 6EY18AL diesel engines of a Multipurpose Vessel class ship with deadweight of 27540 tons. The objective of research is to determine the effect of the structural characteristics of the oil layer (contact angle and thickness) on the performance parameters of a marine diesel engine and the performance characteristics of the oil used in its circulating lubrication system. At the same time, the compression pressure, the concentration of nitrogen oxides in the exhaust gases, and the temperature of the exhaust gases after the cylinder are considered as the operating parameters of the diesel engine; as performance characteristics of the oil – its Base Number, as well as its Wear and Contaminant Elements. The studies are carried out on two diesel engines of the same type, in the circulating lubrication system of which oils with different structural characteristics were used. Structural characteristics of the oil layer were determined by ellipsometry. The operational characteristics of the diesel engine – using the Doctor diagnostic system. Oil performance – by spectrographic analysis. It has been established that an increase in the contact angles of wetting and the thickness of the oil layer improves the heat and power and environmental performance of a diesel engine. At the same time (for the period of operation of diesel engines 500–1000 hours), the decrease in compression pressure in the cylinder slows down, the temperature of gases after the cylinder decreases, and the emission of nitrogen oxides with exhaust gases decreases. In addition, the wear of diesel parts and oil oxidation are reduced. The information obtained in the course of the study on the structural characteristics of motor oils will provide the possibility of their selection and further use of those that will contribute to a better maintenance of the operational performance of marine diesel engines. [ABSTRACT FROM AUTHOR]

The purpose of the study was the research concerning the emissions of limited exhaust gas components of the AVL research engine equipped with common rail injection system, fuelled with different biodiesel blends and diesel fuel as reference. In details, the engine was powered with mixtures of rapeseed methyl esters with diesel fuel in the volumetric ratios of 10:90, 20:80, 30:70, 40:60 and 50:50. The tests were performed at: 1200, 1700 and 2200 rpm and the torque T = 5–35 Nm (step 5 Nm). The analysis of the obtained results showed that the emissions of hydrocarbons from the tested engine fuelled with biodiesel are lower than that of diesel fuel. Carbon monoxide emissions are also lower, except for low rotational speeds and low engine load T = 5–20 Nm. As for nitrogen oxides emissions, it is also lower than that for the diesel fuel, except for high engine loads, in the range above 25 Nm, for each rotation speed of the engine load characteristics. Moreover, in this research it was confirmed that emission of particulate matter is also slightly reduced for the engine fuelled with tested blends. [ABSTRACT FROM AUTHOR]

The article presents the laboratory tests results of the influence of the diesel oil content in a mixture with rapeseed oil on the operating parameters of a diesel engine with the common rail fuel supply system. Fuel mixtures with a rapeseed content of 0, 50, 70, 100% were used. The article presents the results of tests carried out for various configurations of the object. The measurements included tests of exhaust gases: the content of carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides as well as specific fuel consumption and exhaust gas temperature. As a result of the research, it was noticed that the use of rapeseed oil causes a significant increase in fuel consumption and an increase in emissions. At a crankshaft speed of 2500 rpm and a torque generated by the engine crankshaft of 12 Nm, the specific fuel consumption for a 0% rapeseed content is 310 g/kWh. For the same engine operating conditions and the same rapeseed content of the fuel, the fuel consumption for 100% rapeseed content is 330 g/kWh. For the same engine operating parameters, analysis of the carbon dioxide content in the exhaust gas yields a value of 7.8×104 ppm for a rapeseed content of 0%. For the same engine operating conditions and for the oilseed rape content in the fuel is 100% 8.4×104 ppm. The mathematical models describing the effects of engine operating parameters and rapeseed oil content in the mixture on the observed values were created with the Scilab program. The degree of agreement of the determined mathematical models was checked by calculating the coefficient of determination (R2). The results are shown in 3D figures. [ABSTRACT FROM AUTHOR]