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This article characterises the methodology for the endoscopic testing of a laboratory diesel engine used for testing marine fuels. The ‘Shadow’ measurement method used in the XLG3 type EVEREST digital endoscope, for quantitative and qualitative identification of detected surface defects, was approximated. Representative endoscopic images of the elements limiting the working space of the research engine are demonstrated, having been recorded during the usable quality testing of newly produced, low-sulphur marine fuels, so-called ‘modified fuels’. The main purpose of the endoscopic examinations was the final verification of the tested fuel’s suitability for feeding full-size marine engines.

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.

The implementation of low-sulphur, so-called modified marine fuels into operation requires prior laboratory engine tests to assess the energy, emission and structural effects of their usage. This type of research are carried out on the test bed of a diesel engine as a small-scale physical model that reproduces the adequate design and process (parametric) features of a full-size marine engine. Their key stage is to determine the energy characteristics of the engine in the steady state of operation determined on the basis of the analysis of the developed indicator diagram and the dynamic characteristics of the transient processes from idling to the reference steady state of load - and vice versa. In this way, the basic diagnostic parameters of the fuel usable quality are determined: the rate of pressure increase in the cylinder and the average deceleration of the engine crankshaft within the strenuous transient process. This article presents representative results of this type of research carried out on six different, low-sulphur marine fuels used to feed marine engines. [ABSTRACT FROM AUTHOR]

Global silk production generates about 1 million tons of spent pupae annually that are generally discarded as waste but could be used to generate about 240 million liters of biodiesel every year. Spent pupae contain about 30–40% oil, 30–40% proteins and about 20–30% carbohydrates which comprise a low‐cost, renewable and sustainable source for production of biofuels, particularly biodiesel. Some studies indicate the potential of converting the pupa oil into biodiesel but there are no reports on the detailed characteristics and the properties and performance of the pupa biodiesel. In this study, oil was obtained from the pupae using mechanical and Soxhlet extraction with yield of up to 95%. The oil was transesterified using acid and alkaline catalysts under different processing conditions. A conversion ratio of more than 90% from oil to biodiesel was possible. Pupae diesel had characteristics similar to regular synthetic‐based diesel with calorific value of between 44 41 MJ kg−1. Pupae diesel was blended up to 50% with regular diesel and performance of the pure and blended fuel was tested on an engine test rig. Engine performance tests showed that the pupa diesel did not compromise the efficiency and produced emissions within the stipulated standards. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The world’s energy demand increases because of increase in human population. The conventional fossil energy resources will be depleted and burning of these conventional fuels increases greenhouse gases and causes global warming. These problems can be overcome using renewable alternative energy resources such as biofuels. In recent years biodiesel is considered as a renewable alternative to the fossil diesel. The utilisation of biodiesel as a fuel in compression ignition engine results in lower CO, HC and smoke emissions as the biodiesel is an oxygenated fuel. The major problem with the biodiesel is its higher NOx emission and different techniques were used to minimise NOx emission. The use of synthetic and nano-metal additives to the biodiesel may affect the environment and hence it is necessary to identify non-toxic, low cost, biodegradable, and sustainable additives to reduce the NOx emission. Hence an attempt was made to use clove oil as a natural additive for the honge oil biodiesel as it has better antioxidant property. The engine tests were conducted with various dosages of clove oil such as 1000 and 2000 ppm and the engine load were increased with an increment of 25% up to full load. The addition of clove oil to the honge oil biodiesel significantly affects the engine NOx and clove oil can be substituted as an additive to reduce the NOx emission of the biodiesel fuelled CI engine and without altering the engine hardware. The clove oil enhances the oxidation stability of the honge oil biodiesel. [ABSTRACT FROM AUTHOR]

A fuel microemulsion based on blend of diesel fuel:sunflower oil (4:1), water, 1-butanol (co-surfactant), and a blend of Tween 80, Span 80 and 1-buthyl-3-methylimidazolium nitrate ionic liquid as surfactant is formulated and optimized regarding the amounts of co-surfactant, water and oily phase. The fuel microemulsions were for upto one year stable on the bench and their density and viscosity were comparable to neat diesel fuel. The size of water droplets in fuel microemulsions are measured by dynamic light scattering (about 10 nm) with a very narrow size distribution. The optimum results are obtained by using a blend of Span 80:Tween 80:1-buthyl-3-methylimidazolium nitrate, 70:26.25:3.75, respectively, as surfactant. The engine combustion tests at various engine speeds and full load indicated that the brake-specific fuel consumption, torque, brake power and exhaust gas temperature are decreased in fuel microemulsion compared to neat diesel fuel. Carbon dioxide and nitrogen oxide emissions were reduced by 4–5%, and unburned hydrocarbons and carbon monoxide emissions were increased by 18.4% and 1.18%, respectively, for optimum fuel microemulsion compared to neat diesel fuel. The results are promising to introduce a way to improve the diesel fuel performance in terms of its environmental impacts. [ABSTRACT FROM AUTHOR]

Biodiesel is considered an immediate substitute for the fossil diesel as the fuel properties, such as calorific value, density, ash content and acid value are comparable to the diesel. In India, pongamia oil has considerable potential for the biodiesel production. The pongamia oil biodiesel has lower volatility and slightly higher viscosity than the diesel. Hence the pongamia oil biodiesel fuelled diesel engine results in lower thermal efficiency as compared to the diesel. The carbon nanotubes (CNTs) were used in this work as additive to the pongamia oil biodiesel, to enhance the atomization and to reduce the ignition delay of the pongamia oil biodiesel. The CNTs were added to the pongamia oil biodiesel with different dosages and subjected to ultrasonication for 60 min, to prepare homogenous mixture. The engine tests were conducted on a single cylinder diesel engine without making any modifications in the fuel injection system. The addition of CNTs to the pongamia oil biodiesel resulted in higher brake thermal efficiency at higher loads between 75 to 100 % of the full load. From the engine tests, it was observed that the CNTs improves the engine thermal efficiency and reduces the CO, HC and smoke emissions of the diesel engine depends upon the CNT dosage. This is due to shorten ignition delay caused by the CNTs which improves the combustion of the pongamia oil biodiesel. The optimum CNT dosage of 50 mg/l results in 4% increase in thermal efficiency and reduces the CO, HC and smoke emissions by 20.33, 25 and 12.5% respectively at full load. [ABSTRACT FROM AUTHOR]

The EU Horizon2020 consortium PHOTOFUEL joined academic and industrial partners from biology, chemistry, engineering, engine design, and lifecycle assessment, making tremendous progress towards engine-ready fuels from CO 2 via engineered photosynthetic microbes. Technical, environmental, economic, and societal opportunities and challenges were explored to frame future technology realization at scale. [ABSTRACT FROM AUTHOR]

The biodiesel has lower volatility and is costlier than the fossil diesel. Hence it is necessary to add a low cost fuel which has higher volatility, with the diesel. The tire pyrolysis oil (TPO) produced from waste tire and tubes have these desirable properties and hence in this work, we have mixed TPO with biodiesel to enhance the properties of the biodiesel. The engine tests were carried out on a single cylinder compression ignition engine with the mixture of biodiesel and TPO as fuel. From the engine tests, it is observed that the fuel mixture results in engine performance close to diesel operation at the higher injector nozzle opening pressure.

This paper describes the results of an engine study of the tendency for fuel injector deposits to form by gasolines of various compositions. Since the factors promoting the formation of fuel injector deposits in DISI engines have, in many cases, been insufficiently identified they require further research and investigation work, which was the greatest motivation for undertaking this project. The latest CEC F-113-KC test procedure for the most damaging deposits in DISI engine injectors was used for this purpose. The research results obtained in the framework of the conducted project indicated T90, aromatic and olefinic hydrocarbons, sulphur, ethanol, DVPE, IBP and fuel density as the most important factors causing the increase in the tendency for deposits to form on the injectors of SI type DISI engines. [ABSTRACT FROM AUTHOR]

The article discusses the tasks of testing tractors on stead equipment to determine their power and fuel and economic indicators. The shortcomings of the available equipment are identified during the test. The role and importance of testing on modern bench test equipment is described. The advantages of new advanced technologies during testing, the use of modern stands and equipment for testing tractor engines are revealed. An analysis of the tests carried out on existing stands and equipment is done, the tasks are set for the use of modern measuring systems that allow to qualitatively increase the level of testing. [ABSTRACT FROM AUTHOR]

Exhaust gas emissions tests of internal combustion engines and the permissible limit values for each component are standardized. This work shows the results of the tests carried out on the Volkswagen 1.9 SDI engine in the Armfield CM12 stationary test bench and the Launch X-431 pro scanner performed in the diesel engine laboratory of the Department of Agricultural Mechanical Engineering (DIMA) of Chapingo Autonomous University (UACh). The methodology of SAE J1995 and ISO 8178 Standards were used to obtain the values of HC, NOx, CO, CO2 and O2. In addition, the variation of lambda λ index was obtained. The characteristics of each component were constructed based on the load (power) and the lambda index. The concentrations were 30.25 g kW-1h-1 for HC + NOx and 0.47 g kW-1h-1 for CO which is below the established limits. [ABSTRACT FROM AUTHOR]

The depletion of conventional energy sources and environmental pollution related to use of these energy sources make biodiesel as a renewable replacement to diesel. The biodiesel can be used as an immediate replacement to fossil diesel as its properties are comparable to diesel. The main drawback of the biodiesel is its lower oxidation stability and prone to microbial growth which degrades the properties of biodiesel during storage. However, these problems can be overcome by adding suitable additives to the biodiesel. The non-edible neem oil is one of the feedstocks used for biodiesel in India. The neem biodiesel has lower oxidation stability and hence it is necessary to add suitable additive. The eucalyptus oil has better antioxidant and microbial inhibition properties and hence it was used as an additive in this work. The effect of adding this additive on the biodiesel properties, engine emissions and performance were studied. The engine tests were conducted on a compression ignition engine at different loads with various concentration of eucalyptus oil. The engine performance indicates that the thermal efficiency of the engine with biodiesel is lower than the diesel fuel while the engine exhaust emissions like HC, CO and smoke were lower with the biodiesel. The use of eucalyptus oil as an additive to the biodiesel at full load increases the engine thermal efficiency by 3.08%. Also, it lowers the engine exhaust emissions except NOx emission. [ABSTRACT FROM AUTHOR]

Permanent improvement of metal structures of up-to-date diesel engines actualizes creation of new, higher quality analogues of motor oils. For some time past the goal-oriented studies into application of multifunctional alkylphenolate additives АКİ (С8-С12) series as calcium salts of formaldehyde condensation with various amines ended in the creation of new lubricants of M-10Г2k и M-14Г2 (API CC, SAE 15W-30; API CC, SAE 15W--40) grades. Experimental samples of lubricant compositions based on compound of basic oils M-8 and M-12 obtained from Baku oils, alkylphenol additives synthesized at the Institute of Chemistry of Additives and viscous additives of Viscoplex (V) series of «Evonik» firm have been appraised by the results of qualification tests on Д-240 engine. [ABSTRACT FROM AUTHOR]

The utilization of alternative fuels in transport is very important due to dependence on petroleum, increaseasing in number of vehicles and as consequence high CO2 emission. The investigations of biodiesel as an alternative fuels include raw materials, production, quality (pure or in mixture with diesel), engine and vehicle tests and determining compliance with sustainability criteria. In this paper, the investigations were performed with the biodiesel prepared from damaged sunflower seed and used cooking oils using the latest technology for the purification of biodiesel from methanol based on ion exchange principle. The main target was to examine the possibility of utilisation of different biodiesel and diesel blends in Compression Ignition (CI) engines and their influence on engine power, torque, fuel consumption and exhaust emission. The results of standard and non-standard investigations and engine and vehicle tests of biodiesel and diesel blends are presented.

The development of new advanced lubricants is a key factor for the production of cleaner and more durable internal combustion engines. New improved anti-friction and anti-wear additives are required to improve the fuel economy and reduce the greenhouse gases emission. The inclusion of nanoparticles known as solid lubricants (MoS 2 and WS 2 inorganic fullerenes) in engine oils could help to improve the performance of internal combustion engines. This paper describes the results of the testing activities performed on a fully formulated engine oil incorporating MoS 2 nanoparticles. The nano-lubricant allowed demonstrating on the New European Driving Cycle (NEDC) a reduction of 0.9% of fuel consumption with respect to the reference lubricant without nanoparticles. [ABSTRACT FROM AUTHOR]

Biodiesel was produced from jatropha curcas oil of Kenyan origin through a two-step acid-base catalytic transesterification process. The relevant physicochemical properties of the produced biodiesel were tested according to appropriate standards and were found to be within the requirements. Engine tests were carried out in an Audi, 1.9 litre, turbocharged direct injection, compression ignition engine at different loads. Emissions were measured by a Horiba emission analyser system while combustion data was collected by a data acquisition system, from which, cylinder pressure and rate of heat release of the test engine in every crank angle were calculated. Though the biodiesel had slightly higher brake specific fuel consumption when compared to fossil diesel, its emission behaviour was significantly better. The combustion characteristics were also slightly higher as compared to fossil diesel. This study therefore concluded that biodiesel derived from jatropha curcas of Kenyan origin can be utilized as a safe substitute for mineral diesel. [ABSTRACT FROM AUTHOR]

Highlights: [•] Possibilities to use algae oil methyl esters as fuel were examined. [•] Characteristics of algae oil methyl esters are presented. [•] Algae and rapeseed oil methyl esters were used for engine tests. [•] Engine and environmental characteristics of engine are presented. [Copyright &y& Elsevier]

Abstract: The presence of the honing scratches/grooves in cylinder liner surfaces is intended and desired as they improve the lubrication and retain the debris reducing the piston assembly/liner friction and consequently improve the fuel economy and longevity of the internal combustion (IC) engines. Axial scratches caused by the abrasive wear between the tribological partners and/or entrained wear particles are undesired since they are correlated with increased oil consumption and noxious emissions of the IC engines. Due to the imperfection of the manufacturing process, the honing grooves, especially the deep ones, are smeared and interrupted by folds. A portion of the folds would eventually detach during the running process and act as abrasive particles increasing the wear in the cylinder. To closely examine the influence of all these features on the liner''s function, it emerges a need to objectively quantify the axial wear scratches, plateau honing grooves, deep honing grooves and their interrupts. The existing techniques fail to segment a groove containing interrupts as they usually appear as summits at several locations in the course of the groove. Combining the profile and image analyses, the deep grooves and their interrupts were successfully identified and quantified in earlier works of the authors. In this paper those algorithms are extended, so that the deep honing grooves, plateau honing grooves and axial scratches crossing different depth levels are sequentially segmented in three levels/steps in an immersing way. A number of parameters derived from this method were utilised to compare 3D interference measurements from the top dead centre, middle and bottom region of a liner run in a truck engine test whereas the three regions represent different wear regimes due to the different running conditions. The results show that: (i) the axial scratches are densest in the top dead centre and about the same size as the plateau grooves in all three regions, while in the bottom region there are only few scratches; (ii) the presence of plateau grooves in the top region clearly decreases, (iii) the deep groove interrupt and coverage are lowest in the top region, and (iv) the groove height and distance between grooves spread mostly. [Copyright &y& Elsevier]

Abstract: The accumulation of deposits in the honing grooves of the cylinder liner surfaces of internal combustion engines is undesirable as they seal the grooves (reducing their oil retention capability) and increase engine''s oil consumption. As part of a long-term programme of truck engine development, after different running times and under similar conditions of load, engine speed and lubrication, a number of grey iron cylinder liners were axially sectioned, measured, inspected and a presence of deposits was discovered. These deposits were characterised in order to gain knowledge about their origin and quantities. The X-ray energy dispersive analysis revealed elements stemming from the oil/fuel (C, O and S), from the detergent (Ca and Mg), from the anti-wear additive (Zn and P), and from some contaminants (K and Si). Higher concentration of S and Ca were mostly found in the honing grooves covered with deposits suggesting a domination of the detergent additive. Deposit thickness measurements obtained by a white light interferometer revealed patchy deposit topographies concentrated at the top region reducing towards the bottom of the liner which was also confirmed by scanning electron microscope measurements. Despite the limitations of the interferometer, it has been shown that the interference measurements are sufficiently reliable for a quick and objective quantification of the overall deposit accumulation. [Copyright &y& Elsevier]

Abstract: The paper presents the results of investigation into the thermal fatigue resistance of thermal barrier coatings (TBC). Two groups of double-layered thermal barrier coatings (TBC) were investigated: plasma sprayed with ZrO2-8%Y2O3, Al2O3-40%TiO2 or Al2O3-40%ZrO2 top coats and powder flame sprayed with ZrO2-30%CaO, Al2O3-40%TiO2 and Al2O3-30%MgO. The extent of TBC deterioration experienced in thermal fatigue test was evaluated in the erosion test and SEM examinations. Flame sprayed coatings were found more prone to damage than plasma sprayed ones. The highest thermal fatigue resistance revealed TBC plasma sprayed with PSZ. Numerical calculation with Abaqus 6.7 finite element code was used to calculate temperature and stress variations in the coating throughout the test. Phase stability of plasma sprayed Al2O3-40%TiO2 was evaluated by means of X-ray diffraction method. Thermal growth of oxides at the top coat/bond–coat interface and the decomposition of Al2O3-40%TiO2 were found to be important degradation mechanisms leading to the spallation of coatings in the diesel engine and the petrol engine exploitation tests. [ABSTRACT FROM AUTHOR]

Abstract: The increased presence of cold work material on cylinder liners due to the introduction of the diamond honing is undesirable as it seals the oil-bearing honing grooves. The most of it is a smeared metal inside the deep honing grooves (blechmantel) that may break and act as abrasive wear particles increasing the bore wear. An attempt has been made to estimate the extent of removal of blechmantel for different wear regimes present at the middle and top region (near the top dead centre) of the liner surface using the least worn bottom region as a reference for comparison. A number of truck grey iron cylinder liners were axially sectioned after varying periods of engine running under similar conditions of load, engine speed and lubrication. 3D surface measurements were taken at the three regions and a range of standard parameters was extracted. Combining the profile and image analysis, an algorithm was developed to identify and quantify the blechmantel. The algorithm has successfully identified/quantified the blechmantel and can be used for automatic surface quality and process control. It was found that the amount of the blechmantel in the middle section was approximately the same (though slightly lower) as that in the bottom section, while there was a considerable dislocation and removal of blechmantel in the top section and thereby it represents one of the possible causes for wear. Axial wear scratches of different size and distribution were observed not only through the whole stroke area, but also in the bottom region. All engines and liners performed well throughout the tests, and the observed quantities of blechmantel and axial scratches are acceptable for the time being. [Copyright &y& Elsevier]

This study is devoted to determining performance characteristics of biodiesel as a diesel engine fuel. An engine performance test using sunflower methyl esters exhibited characteristics very similar to regular diesel. The test values obtained from a 2.5 lt. 4 cylinder Peugeot XD3p157 engine shows that torque values obtained by the two types of fuels are 5%–10% in favor of regular diesel. Obviously, power values will be the engine revolutions times this percentage with regular diesel. Specific fuel consumption, however, is better with biodiesel. This means that a better combustion characteristic is achieved with biodiesel, which compensates for its lower calorific value. Soot emissions are slightly less with biodiesel, as expected, due to the improvement in specific fuel consumption. [ABSTRACT FROM AUTHOR]

In this study, the non-food use of Brassica carinata oil for biodiesel production was investigated. B. carinata, a native plant of the Ethiopian highlands widely used as food by the Ethiopians, has recently become object of increasing interest. This is due to its better agronomic performances in areas such as Spain, California and Italy that are characterized by unfavorable environmental conditions for the cultivation of Brassica napus (by far the most common rapeseed cultivated in continental Europe). The agronomic performance and the energetic balance described here confirmed that B. carinata adapted better and was more productive both in adverse conditions (clay- and sandy-type soils and in semi-arid temperate climate) and under low cropping system when compared with B. napus. The biodiesel, produced by transesterification of the oil extracted from the B. carinata seeds, displayed physical–chemical properties suitable for the use as diesel car fuel. A comparison of the performance of B. carinata oil-derived biodiesel with a commercial biodiesel and petroleum diesel fuel was conducted as regards engine performance, regulated and unregulated exhaust emissions. These results make B. carinata a promising oil feedstock for cultivation in coastal areas of central-southern Italy, where it is more difficult to achieve the productivity potentials of B. napus, and could offer the possibility of exploiting the Mediterranean marginal areas for energetic purposes. [Copyright &y& Elsevier]

An experimental study of the effects of thin thermal barrier coatings on the performance of a diesel engine was conducted. Results obtained from the engine with thermally insulated pistons were compared with the baseline engine data. Engine trials demonstrated good properties of both coating systems. Temperature and stress distributions within the pistons were evaluated analytically by means of the Cosmos/Works FEM code. Results of a road test on a gasoline-engine-driven car are also reported. The performance of the modified engine-driven car was found satisfactory. The ceramic coating did not produce observable knock in the engine, no significant wear of piston skirts or cylinder liners was found. [Copyright &y& Elsevier]

Vegetable oils may be used directly as an alternative diesel fuel in compression-ignition engines. Within the scope of this work, employment of sunflower oil in a diesel engine during short- and long-term engine tests were studied, and the fuel characteristics of sunflower oil with its positive and negative aspects are put forward along with our recommendations. [ABSTRACT FROM AUTHOR]