Fuel Injection Equipment Research Articles

Study on Selection of Diesel Engine Exhaust After-Treatment System Materials and Emission Performance for Genset Applications

The use of diesel engines for the transportation sector is ubiquitous and covers a broad continuum, like buses, trucks, agriculture, construction equipment, generators, and industrial applications. However, because of their increased use of off-road engines, they contribute more emissions in various sectors than on-road. As a result, worldwide, regardless of ongoing emission control efforts, these off-road, stationary engines also continue to be a substantial source of air pollutant emissions in the United States, European Union and Asian markets. Accordingly, while improving emissions performance, the selection of after-treatment system materials and the use of compatible after-treatment specification selections are also critical. This is only possible by effectively combining clean diesel technologies such as Fuel Injection Equipment (FIE), Turbocharger with Intercooler (TCIC), Cooled Exhaust Gas Recirculation (C-EGR), and after-treatment systems like Diesel Oxidation Catalyst (DOC), Selective Catalytic Reduction (SCR), and Diesel Particulate Filter (DPF). Overall, in this study, the influence of after-treatment system configurations and their effect on emission reduction performance are studied for three different DOC specifications based on emission testing for catalyst and size optimization. With the selected DOC catalyst specification, suitable combinations of DPF and SCR specifications are optimized further using GT-SUIT software simulation. This study was carried out during the conversion of a 15 kW NA engine to a 27 kW TCIC engine to meet diesel engine emission norms.

Ultra-low soot/ particulate emissions from a dimethyl ether-fueled agricultural tractor engine

This study eveluates using dimethyl ether (DME) fuelled engine for marching towards zero soot and particulate matter (PM) emissions in the agricultural sector. Comparative emissions and particulate characteristics were analysed for a customised DME-fuelled engine and an unmodified baseline diesel engine. The experimental investigations were performed on a multi-cylinder tractor engine using a dedicated DME fuel injection equipment (FIE) and an unmodified diesel FIE. Regulated emissions, namely carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NOx), smoke opacity, and particulates were measured at three engine speeds (1200, 1600 and 2000 rpm) and five loads (1.29, 2.59, 3.88, 5.18, and 6.47 bar BMEP). The static fuel injection timing for both test fuels was maintained constant; however, the actual injection timing could be slightly different for both test fuels because of their different physicochemical properties. DME-fuelled engine exhibited relatively higher HC and CO emissions than diesel at low loads; however, both test fuels exhibited nearly identical emissions at higher loads. NOx emissions were lower for DME-fuelled engine than baseline diesel, and its smoke opacity was also negligible at all engine loads and speeds. The particulate number concentration for DME-fuelled engines was much lower than baseline diesel at all test conditions, except 1.29 bar BMEP. Particulate emissions from DME-fuelled engine were mainly in the form of nanoparticles and nucleation mode particles, with negligible numbers of accumulation mode particles. This experimental study demonstrated that DME-fuelling of the tractor engine reduced emissions and it can be used as a sustainable and greener fuel to develop cleaner engines for agriculture/ transport sectors.

Dimethyl ether fuel injection system development for a compression ignition engine for increasing the thermal efficiency and reducing emissions

In this study, a dedicated fuel injection equipment (FIE) for a 100% dimethyl ether (DME)-fueled three-cylinder engine was developed. DME has a cetane number (>55) higher than baseline diesel (40–50), making it a promising compression ignition (CI) engine fuel. However, some physicochemical properties of DME, namely lubricity, viscosity, density, calorific value, vapour pressure, incompatibility with elastomers, etc., necessitate modifications in the existing FIE to deliver a power output equivalent to baseline diesel fuelled engine. Modifications included customized DME storage tanks, supply lines, return lines, and a pneumatic pre-supply feed pump. In addition, a customized high-pressure pump (HPP) (inline mechanical pump) and a set of modified injectors with larger nozzle hole diameters were used for the DME engine. The engine speed was varied from 1000 to 2000 rpm, and off-road operating conditions were simulated using a non-road steady cycle (NRSC). A detailed evaluation of the FIE for its comparative combustion, performance, and emissions characteristics of DME was conducted vis-à-vis baseline diesel. The DME-fuelled engine showed an increase of ∼4.7% in brake thermal efficiency (BTE) under full load conditions and an increase of ∼8.32% BTE under simulated non-road-testing conditions. In addition, the DME-fuelled engine exhibited no visible smoke and negligible soot in the engine exhaust. DME combustion reduced HC emissions by ∼50% at low and medium engine speeds, and a ∼100% reduction was seen at higher engine speeds compared to baseline diesel engine. The CO emission decreased by ∼90%, and the CO2 emissions were ∼15% lower for DME. Lower exhaust gas temperature (EGT) and lower heat release rate (HRR) during premixed combustion indicated that DME-fuelled engine acted as a low heat rejection (LHR) engine. This study demonstrated a 100% DME-fueled engine with a customized FIE, delivering higher thermal efficiency and lower emissions than conventional diesel engines for on- and off-road applications.

Use of fuel injection equipment with increased injection pressure for reducing environmental footprint

BACKGROUND: Environmental pollution causes a number of irreversible consequences, including those associated with climate warming, acid precipitation, deterioration of climatic conditions and others. The problem of reducing harmful emissions of diesel engines containing in exhaust gases is currently relevant, as the implementation of the EURO 4/5/6 standards is becoming increasingly difficult for both new automotive equipment and those already in operation.
 AIMS: Reduction of harmful emissions into the atmosphere and reduction of environmental footprint by increasing the fuel injection pressure in a diesel cylinder.
 MATERIALS AND METHODS: The 6Ch15/18 (7D6-150) diesel engines, having nominal power of 110 kW at 1500 min-1, specific effective fuel consumption of 224 g/(kWh) and oil burn of 0.32% of the fuel consumption intended for diesel generator units, were tested. During steady-state tests, diesel exhaust gases were collected to analyze their composition and determine the dispersion of solid particles (SP) with an increase in fuel injection pressure by tightening the nozzle springs.
 RESULTS: It was revealed that with an increase in the tightening of the nozzle springs and an increase in the injection pressure (PI), emissions of solid particles with exhaust gases decrease, and the fuel efficiency of diesel increases. As a result of the tests carried out, it was found that with an increase in the springs tightening of the injectors from (PI increased from 160 to 185 kPa), emissions of nitrogen oxides (NOx) decreased by 15%, emissions of carbon monoxide (CO) decreased by 15%, emissions of hydrocarbons (CxHy) decreased by 54% and emissions of solid particles (SP) decreased by 33%. Improved mixing and better preparation of fuel for combustion explain the change in CO emissions with the PI increase. The emissions of CxHy indicate a significant improvement in the completeness of fuel combustion in the cycle. Emissions of solid particles containing in exhaust gases are reduced due to the intensification of mixing of air and fuel vapor, contributing to a more complete burn-off of soot in a cylinder. The CxHy emissions are reduced and meet the EURO-3 and EURO-4 standards. The environmental footprint was as follows: NEF = 51.34 Сt/year at PI = 160 kPa and NEF = 43.66 Сt/year at PI = 185 kPa, which indicates a decrease in the environmental footprint by 1.17 times or by 15%.
 CONCLUSIONS: The practical value of the study lies in the possibility of using fuel injection equipment with increased fuel injection pressure into a cylinder to reduce harmful emissions from diesel exhaust gases down to the required standards.

Cyclic Combustion Variability of Dimethyl-Ether-Fueled Agricultural Tractor Engine

Abstract Combustion in dimethyl-ether (DME)-fueled engines needs to be assessed carefully for its widespread acceptability from a drivability viewpoint. Since the test engine used in an off-highway segment, it was tested in a steady-state cycle for engine performance, combustion, emissions, and their cyclic variations, which were the only parameters to assess the drivability. This study investigated and analyzed the cyclic variations of a 100% DME-fueled engine equipped with modified mechanical fuel injection equipment. It was compared with baseline diesel to understand its positive and negative aspects. Experiments were conducted at different engine speeds (1200,1600, and 2000 rpm) and loads (No Load, 1.29, 2.59, 3.88, 5.18, and 6.47 bar brake mean effective pressure (BMEP)) . In-cylinder pressure was recorded for 250 consecutive engine cycles, and many combustion parameters were comparatively analyzed for diesel and DME fuelings. The coefficient of variation (COV) of maximum in-cylinder pressure (Pmax) was lower for DME than diesel at 1600 rpm and comparable at the other remaining engine speeds (1200 and 2000 rpm). Variations in COV of Pmax were higher at low loads and negligible at high loads for both test fuels. At 2000 rpm, the crank angle positions at which Pmax occurred were distributed in a narrow range for DME, representing higher combustion stability than baseline diesel. Variations in the maximum rate of pressure rise (RoPRmax) were lower for DME at 3.88 and 6.47 bar BMEP, while these were higher at 1.29 bar BMEP than baseline diesel. COV of indicated mean effective pressure (COVIMEP) decreased from lower to higher loads for diesel and DME fueling at 1600 and 2000 rpm engine speeds. The differences in COVIMEP between diesel and DME were negligible at higher loads, representing engine stability similar to baseline diesel. Combustion parameters assessed indicated that DME fueling led to lower cyclic variations than baseline diesel as the engine operated from lower to higher loads. At lower loads, DME fueling showed higher cyclic variations than baseline diesel.

Діагностика паливної апаратури, приводу клапанів газорозподілу та форсунок змащення циліндрів сучасних двотактних двигунів

The application of a vibration sensor with an in-cylinder pressure sensor extends the capabilities of internal combustion engines and compressor diagnostics for various types of plants and installations, such as marine diesel engines, refrigeration piston compressors, aircraft engines. The fuel injection equipment malfunctions as valve as valve train system malfunctions could be detected from the experimental indicated diagrams P(V), P(deg) of the engine cylinder operating process as it is known. The main indicators are the following: the shape of the diagram and the parameters of working cycle – the maximum combustion pressure Pmax, the compression pressure Pcomp, mean indicated pressure IMEP, etc. However, it should be considered that different types of malfunctions could have the same reflection on the indicated diagram. For instance, the late fuel injection and the fuel-injection equipment wear could have almost similar effects on the indicated diagram and main diagnostic parameters. Another example is the low compression pressure Pcomp, which could be caused by the cylinder or compression rings wear and by the exhaust valves wrong timing or valve leakage. It should also be mentioned that many types of malfunctions at their early stages are very difficult to detect and clarify based solely on the indicated diagrams analysis. The detection of such malfunctions usually requires the direct measurements of the fuel injection pressure and injector’s needle lift diagrams with accurate valve timing measurements. However, mentioned measurements could be performed under laboratory conditions and are difficult to apply under engine operating conditions. The vibration sensor application could be a reasonable alternative to the direct measurements, as it allows the determination of the injector’s needle lift-off and landing timing, high-pressure fuel pump cut-off and discharge timing, the preheated heavy fuel circulation start/stop timing as well as gas-distribution valves opening and closing timing, the oscillation frequency, and amplitude from the refrigeration system piston compressor valve operation and the cylinder oil injector timing. The vibration sensor has a magnetic basement that allows its easy mounting on the engine parts. All this information could be directly measured during engines and compressor trials by the vibration sensor applied in the advanced diagnostic systems.

Feasibility study of novel DME fuel injection Equipment: Part 1- fuel injection strategies and spray characteristics

The Methanol Economy is projected as a sustainable solution to the impending global energy crisis. Methanol and Dimethyl Ether (DME) are projected as exceptional alternative fuel solutions to power future mobility, ensuring the continued growth of internal combustion engines (ICEs) in an environmentally sustainable manner. In this study, the technical feasibility of DME as an alternative to diesel is assessed using a three-dimensional computational fluid dynamics (3D-CFD) simulation approach. A novel fuel injection equipment (FIE) is computationally assessed for DME induction into the engine. A water-cooled, naturally-aspirated, compression ignition (CI) engine used for off-highway application is simulated for using DME as a complete replacement of mineral diesel. First, the baseline diesel combustion calibration is done to validate the simulation model using experimental data. For this, a 3D CFD closed-cycle model of a detailed chemistry-based solver is used. Spray characteristics revealed that DME exhibited faster evaporation than diesel, resulting in lesser fuel-rich pockets in the combustion chamber. DME fueled engine is anticipated to be more thermally efficient due to DME combustion’s lower turbulence kinetic energy, which reduces gas side heat transfer through the cylinder walls. DME’s higher total in-cylinder mass results in a lower swirl momentum and a reduced swirl ratio for the DME. The proposed FIE promotes a superior Mean Effective Injection Pressure (MEIP) and ameliorated spray penetration characteristics. This study provides systematic guidelines for selecting an appropriate FIE for DME, with Nozzle Through Flow (NTF) and MEIP tuned to achieve the best possible spray characteristics to develop an efficient and clean combustion system for the given application.

Feasibility study of novel DME fuel injection equipment: Part 2- performance, combustion, regulated and unregulated emissions

Dimethyl Ether (DME) has emerged as a suitable alternative fuel for compression ignition (CI) engines. It is expected to be substitute fossil diesel on a large scale due to its favourable combustion characteristics and sustainable production. This study evaluates the combustion and emission characteristics of a 3-cylinder, water-cooled CI engine fuelled by DME for off-road vehicles, typically used in the agriculture sector. A detailed-chemistry based 3D CFD software is used for simulations in this study. The findings indicate that the baseline diesel fuel injection equipment (FIE), when used for DME injection, is inadequate to match the reference diesel engine performance. Therefore several modified configurations are evaluated in this study using a simulation approach. Modified fuel injection equipment (FIE) significantly reduced the emissions of NOx, soot, UHC, CO and VOC without compromising the base engine power generation. Due to the lower ignition delay of DME, the observed start of ignition advanced. It led to a lower peak firing temperature than its diesel counterpart. The lower cooling loss ratio of the DME engine established its potential as a low-heat-rejection engine. The lower calorific value of DME leads to a 50% increase in the specific fuel consumption than diesel. However, these two fuels seem to be similar on a specific energy consumption basis. A comprehensive study of the un-regulated emission species such as formaldehyde (CH2O), hydrogen peroxide (H2O2), methane (CH4), ethylene (C2H4), and acetylene (C2H2) indicate that DME combustion results in lower unregulated emissions than baseline diesel. A higher number of nozzle holes and an increased mean effective injection pressure (MEIP) of the FIE generate a conducive environment exhibiting superior engine performance and reduced emissions. However, the study identifies a few aberrations in the operating conditions, which show deteriorated emission trends, which should be avoided during the physical engine testing on DME. This study showcases the tremendous potential of an oxygenated fuel such as DME to facilitate the emergence of thermally efficient and cleaner engines, with very low regulated and unregulated emissions, indicating their future for off-highway vehicles.

Расширение функциональных возможностей диагностического стенда ДД 10-01

The work considers questions related to the diagnosing of high-pressure fuel-injection equipment of modern diesel engines. Comparative analysis of the use of modern benches for testing injectors and fuel-injection equipment of motor-and-tractor diesel engines on the basis of common-rail injection system “Common Rail” is cited. Engineering modification of fuel bench DD 10-01 for testing injectors of common-rail injection system “Common Rail” of “Euro 3, 4, 5, 6” class was proposed with regard to the requirements for the design of modern test benches. Functionality of modified bench DD 10-01 with specification of main characteristics and its basic measures when testing injectors of modern diesel engines is considered in detail. Test calculations of basic components of modified bench drive were carried out using computer simulation by means of strength analysis. Keywords: TEST BENCH, COMBUSTION ENGINE, POWER SYSTEM, INJECTOR, PRESSURE, DRIVE, CLUTCH

BIODIESEL AS A LUBRICITY ADDITIVE FOR DIESEL FUEL

Sulfur in diesel fuel will influence particulate matter emission either in exhaust gasflow or in atmosphere. The other effect of sulfur it can cause corrosion and engine wear.Further, sulfur also can influence on catalytic system in exhaust pipe. Due to this reasonsulfur level in diesel fuel should be set as lower as possible. The process can be used toreduce sulfur level is desulfurization process (hydrotreatment). At the hydrotreatment todesulfurize diesel fuel, lubricity can decrease, it is cause by reduction of fuel componentswhich have good natural lubricity.Lubricity, is very relevant to the satisfactory operation of diesel fuel engines whichrelay on the fuel to lubricate many of the moving and rubbing metal parts of the fuelinjection equipment. Some injection equipment may be at risk if operated on fuels of lowlubricity.Biodiesel as results of transesterification has a good lubricity, the test results of addingbiodiesel into a lower lubricity of diesel fuel indicate that biodiesel can be used to increasediesel fuel lubricity.

Formation of a Flow-Line Technical Diesel Engine by the Method of Safety-Free Diagnostics

The analysis of diagnostic methods of diesel engines is given. The principle of diagnostics by certain methods, parameters, by which the diagnostics of fuel injection equipment is conducted, as well as disadvantages of one or another method are considered. The main causes of derangements in the nodes of the fuel injection equipment of diesel engines are determined. The examples have proved that the direct diagnostics methods are the most effective in determining correlation dependencies, for example, indicating the workflow in a diesel cylinder. It is particularly established that the methods of technical diagnostics do not require dismantling of the fuel injection equipment and have proven themselves to be versatile and operative, allowing to comprehensively evaluate the condition of the diesel. The methods of non-separable diagnostic of the condition of a diesel engine are described in detail, the features of such indirect diagnostic methods as vibration, acoustic, indirect indicating by determining the voltage in the cylinder head studs, estimation of the wear rate of component parts with a metal content in engine oil, as well as diagnosing with uneven rate speed of the crankshaft. The vibro-acoustic diagnostic method of a diesel engine can be used to determine the technical condition of such elements as a diesel fuel injection pump , nozzles, and a fuel-priming pump. In addition, the characteristics of motor testers, highly specialized testers and auto scanners are given. A diagnostic feature using a computer auto scanner is that it allows evaluating the condition of nodes in a comprehensive manner, that is, taking into account the mutual influence of derangements on each other. It is noted that the methods that do not require disassembling can be considered the most effective, and the most accurate assessment of the technical condition of the diesel fuel system can be given using the diagnostic method according to the parameters of work processes.

Stage 3a environmental compliance of the 6-cylinder tractor engine

The development strategy of the Minsk Motor Plant, implemented within the framework of plant and state scientific and technical programs, is aimed at producing competitive products that meet modern technical requirements of international standards and quality. The mandatory requirement for the successful promotion of diesel engines on the off-road vehicle market is to ensure the required environmental performance, with low fuel consumption and low engine cost. The well-known technical solutions aimed to achieve environmental indicators of the Stage 3A level significantly increase the cost of diesel engines, therefore, the achievement of the required environmental standards without a significant increase in the cost of engines can be considered an urgent task. Purpose. Stage3A Environmental Compliance for 6 Cylinder Tractor Diesel. Methodology. Experimental studies were carried out for diesel engines equipped with: a Common Rail BOSCH accumulator fuel supply system with an injection pressure of 140 MPa, injectors with 7 nozzle holes; a direct-action fuel supply system with a MOTORPAL fuel pump providing a maximum injection pressure of 100 MPa, MOTORPAL injectors and AZPI with five nozzle holes; combustion chambers of two types with bowl diameters of 55 and 67.5 mm; cylinder heads providing swirl ratios 3–4 and 3.5–4.5; high pressure exhaust gas recirculation system. The tests were carried out at characteristic points of the NRSC cycle at three crankshaft speeds: minimum idle speed 800 min-1, maximum torque 1600 min-1, and maximum power 2100 min-1. Results. It turned out that it is possible to achieve Stage3A emissions standards on 116 kW diesel engines using direct fuel equipment and a semi-open combustion chamber, on 156 kW diesel engines using a Low Cost Common Rail fuel supply system and an open combustion chamber. Originality. The results of the combustion chamber shape choice, the parameters of the fuel-injection equipment, the swirl ratio of the inlet channels, valve timings and parameters of the exhaust gas recirculation system made it possible to organize diesel engine workflow of the Stage 3A ecological level. Practical significance. Construction elements of the six-cylinder diesel engines have been developed and introduced at the Minsk Motor Plant.

Di-ethyl ether-diesel blends fuelled off-road tractor engine: Part-II: Unregulated and particulate emission characteristics

The use of oxygenated fuels, including ethanol, methanol, diethyl ether (DEE), and dimethyl ether (DME) in CI engines has emerged as an effective way to reduce CO, HC, and PM emissions. DEE, in particular, has significant potential to be used in CI engines. Unlike DME, it exists as a liquid state at room temperature and pressure, making its handling very smooth. In this experimental study, DEE-diesel blends were used to power an off-road tractor engine. Previous studies investigated the performance and regulated emission characteristics of DEE-fueled vehicles/ engines; unregulated emissions and particulate characteristics were not studied thoroughly. This study, therefore, investigates the effect of DEE-diesel blends on unregulated and particulate emissions from the engine. Unregulated pollutants investigated in this study include individual oxides of nitrogen (NO, NOx, NO2), saturated and unsaturated hydrocarbons (n-pentane (n-C5H12), n-octane (n-C8H18), iso-butene (iso-C4H8)), and organic and inorganic species (Sulphur dioxide (SO2), formic acid (HCOOH) and formaldehyde (HCHO)). Particulate emission characteristics include total particle mass (TPM), total particle number (TPN), particulate mass-size distributions, and count mean diameter (CMD). Four test fuels were used in this study namely: DEE0, DEE15, DEE30 and DEE45 (0%, 15%, 30% and 45% DEE (v/v) blended with mineral diesel). The results from DEE-diesel blends were compared with baseline mineral diesel (DEE0). The experiments were conducted at a constant engine speed of 1500 rpm at varying engine loads. At all engine operating conditions, DEE-diesel blends resulted in significantly lower TPN compared to baseline mineral diesel. A similar trend was observed for TPM; however, DEE15 showed slightly higher TPM than baseline mineral diesel. Emissions of individual oxides of nitrogen were also relatively lower than baseline mineral diesel. The addition of DEE in mineral diesel exhibited a slight increase in unregulated emission species concentrations such as formaldehyde, formic acid, sulfur dioxide, n-pentane, n-octane, iso-butene. However, the absolute concentration levels were still quite low. This study concluded that DEE could potentially displace mineral diesel partially, without any changes in fuel injection equipment, and achieve an improvement in PM-NOx trade-off in off-road transport diesel engines.

Engine durability and lubricating oil tribology study of a biodiesel fuelled common rail direct injection medium-duty transportation diesel engine

Biodiesel has emerged as a viable alternative to mineral diesel in the transport sector to replace fossil fuels partially. However, long-term compatibility with engine hardware must be evaluated to ensure a smooth transition. Long-term material compatibility studies of Karanja oil methyl ester (biodiesel) blends with the hardware of a modern common rail direct injection system equipped diesel engine used in sports utility vehicles have been carried out in this investigation. A long-term endurance test was carried out in two phases, each lasting 274 h and utilizing (i) baseline mineral diesel and (ii) a 20% v/v Karanja biodiesel blended with mineral diesel (KB20). After completing the first phase, the engine was dismantled, and essential engine components were investigated for carbon deposits and physical wear using several techniques. Before proceeding with the next phase of the endurance test KB20, new engine components were installed in the engine, and then the test was executed. The KB20-fuelled engine exhibited lower wear on the valves and crankpins but higher wear of liners, piston rings, pistons, gudgeon pin, small and big end bearings of the connecting rod, and the main bearings. Fuel chemistry affected the lubricating oil efficacy and its residual useful life. Lubricating oil from the KB20-fuelled engine exhibited a higher increase in density and ash content. KB20 fuelled engine's lubricating oil underwent higher oxidation and polymerization. The surface roughness characteristics of the cylinder liner were measured before and after the endurance test for comparative wear evaluation during both phases of the endurance test. Carbon deposits on the cylinder head, piston top, and injectors were compared, and the pistons of the KB20 fuelled engine exhibited higher carbonaceous deposits. Biodiesel blends harmed the CRDI engine's fuel injection system. Biodiesel harms the fuel injection equipment (FIE) of the CRDI engine. Various tribological tests were performed on the lubricating oil samples collected regularly to examine the compatibility of KB20 vis-à-vis mineral diesel. This series of tribological tests on the lubricating oil samples assessed the effect of fuel chemistry on the lubricating oil's performance and residual useful life. Tests included variations in lubricant density, viscosity, flash point temperature, moisture content, pentane and toluene insoluble, and copper corrosion with time. The study summarily concluded that Biodiesel blends could be utilized in a CRDI engine without causing major engine durability or lubricating oil degradation issues.

Nozzle configuration and in-cylinder pressure effects on fuel spray behaviour: studies using a rapid cycling machine

Efforts to improve the efficiency of internal combustion engines in applications such as heavy-duty vehicles where electric propulsion is currently unfeasible or need complementing are essential. However, studying the conditions of actual internal combustion engines whilst accessing their combustion chambers whilst they are in operation remains difficult. To allow for the characterization of practical operating conditions of diesel engine designs, detailed studies examining the influence of the injector nozzle configuration, peak in-cylinder pressure conditions, and fuel injection pressure values up to 25% greater than those hitherto typically reported using rapid cycling machines for diesel spray diagnosis were carried out. A rapid cycling machine using a production diesel engine piston design, equipped with optical windows and fitted with a high-pressure common rail fuel injection equipment was used with temporal spray liquid and vapour penetration values obtained using Schlieren and Mie scattering imaging techniques for injector nozzles of various k-factor values. Even though the effects of the different injector nozzle conicity values on the fuel spray liquid and vapour penetration values observed were not significant, the studies supported the use of such methods to evaluate the piston and cylinder wall wetting which can have significant effects on the emissions and fuel consumption from internal combustion engines. These are also useful for internal combustion engine design and numerical spray code development.

Pump elements recondition by electrolytic chromium plating

Improving the efficiency of maintenance production in agriculture closely connected to the creation and implementation of such methods of repair and recondition of elements that improve the physicomechanical and service properties of wear joint assemblies.The presence of a nitrided case on the surface of elements lays the groundwork for obtaining a complex covering based on chromium nitrides. Electrolytic chromium plating is one of the ways to recondition elements that increase the service life and machines reliability, and reduce maintenance cost. However, the widespread adoption of chromium plating for the recondition of worn elements is hold back by the low productivity of the process. Therefore, the intensification of chromium plating in reconditioning worn-out machine elements is an urgent problem. It is advisable to recondition critical parts subjecting to abrasive wear, for example, precision vapors of fuel injection equipment, with chromium plating. However, the low productivity and high-energy consumption of the process require the improvement of the electrolyte in order to increase the current output of chromium and the permissible cathode density. The article describes a method for improving the quality of an electrolyte, a method for increasing its versatility, namely the supplementation of various organic additives and complexing substances into it.

RESEARCH OF RESIDUAL LIFETIME OF DIESEL ENGINES FUEL INJECTION EQUIPMENT BY MEANS OF FUEL INJECTION MATHEMATIC SIMULATION

On the basis of the engineering practices of the last 3-4 decades, it is known, tested and proven that, while mathematical models provide reliable descriptions of processes, cycles or physical phenomena, in theoretical research the theory of small deviations is comprehensively preferable to any experiment on regulating characteristics. Considering the fact that all parameters and characteristics are sometimes interconnected by nonlinear dependences, it is impossible to distinguish the influence of a specific parameter on the sought-for value, and can be even hazardous if the determinant argument or its derivative has extreme values. The role of mathematic simulation to determine the residual lifetime of the fuel injection equipment of diesel engines was established. It was also noted that for a reliable description of the processes going on in the fuel injection equipment it is advisable to use the method of small deviations. The mathematical model is based on the known physical laws that describe the interdependence of the two groups of parameters: engine variables and performance parameters - both within the groups and between them. The transition of classical differential equations describing the processes of fuel supply and injection taking into account fuel leaks in precision pairs to the equations with small deviations of parameters is shown. An analysis of correlations between the parameters of injection, fuel supply and fuel leakage was carried out and the most influential parameters were found. The influence coefficients are found and correlations between the influence coefficients and the corresponding parameters are constructed. We used the correlations found to describe the influence of the technical condition of precision pairs on the engine performance indicators. The correlations between the change in injection patterns and small deviations of the parameters describing technical condition of precision pairs are also established.

Field-Testing of Biodiesel (B100) and Diesel-Fueled Vehicles: Part 4—Piston Rating, and Fuel Injection Equipment Issues

AbstractThis study investigated the use of biodiesel (B100) and baseline diesel in two identical unmodified vehicles to realistically assess different aspects of biodiesel's compatibility with modern common rail direct injection (CRDI) fuel injection equipment (FIE) and evaluate biodiesel's long-term durability/compatibility with engine components. Two identical vehicles were fueled with biodiesel (B100) and baseline mineral diesel for 30,000 km field-trials on highway under identical operating conditions. Exhaustive experimental results from this series of tests are divided into four segments. The fourth and the last paper of this series compares the effects of long-term usage of biodiesel on piston deposits and FIE components compared to baseline mineral diesel. A key challenge for improving engine performance and fuel economy is the reduction of frictional losses, primarily at the piston ring–liner interface, which accounts for majority of frictional losses. Piston rating was done for the two vehicles after the conclusion of field-trials and it revealed that rating of different piston sections was ∼5–15% superior in case of biodiesel-fueled vehicle compared to that of diesel-fueled vehicle. Performance of FIE components such as fuel filter, fuel injectors, and fuel pump was assessed after the conclusion of field-trials. Pressure drop at different fuel flow-rates across the fuel filter was measured for assessing the fuel filter blockage. Pressure drop across biodiesel filter was ∼30% higher than diesel filter after 10,000 km usage but almost twice after 15,000 km usage. These experimental results indicated that some additional technical measures should be taken by automotive manufacturers to offset these technical challenges before biodiesel is adapted on a large-scale in modern CRDI vehicles.

Internal Diesel Injector Deposit Chemical Speciation and Quantification Using 3D OrbiSIMS and XPS Depth Profiling

<div class="section abstract"><div class="htmlview paragraph">The impact of internal diesel injector deposits (IDIDs) on engine performance, efficiency and emissions remains a major concern in the automotive industry. This has been compounded in recent years by fuel injection equipment developments and changes to diesel fuel towards ultra-low sulfur diesel (ULSD) and biodiesel as well as the introduction of new fuels such as hydrotreated vegetable oil (HVO). Prevention and mitigation of such deposit formation requires an understanding of the formation process, which demands a chemical explanation. The chemistry of these deposits therefore remains a key research interest to the industry using the latest analytical methodologies to inform and build further on previous investigations. In this work, 3D OrbiSIMS analysis using a time of flight-secondary ion mass spectrometer (ToF-SIMS) with hybrid Orbitrap<sup>TM</sup> functionality has been employed for chemical speciation and depth profiling of IDIDs in-situ on two injector needle samples from field failures in China and Eastern USA. The instrument’s soft gas cluster ion beam (GCIB) and high mass resolution enables unequivocal identification of chemistries from several classes of compounds. Here, chemistries identified include alkylbenzene sulfonates, zinc oxides, sodium and calcium salts, carboxylic acids, carbonaceous/polyaromatic hydrocarbons and metal substrate related material. With depth profiling, the distributions of these materials are traced throughout the deposit thickness. Given the semi-quantitative nature of SIMS data, X-ray photoelectron spectroscopy (XPS) depth profiling using an argon GCIB has also been employed to provide parallel data of atomic concentration through the deposit thickness. This data is complementary to SIMS as it places the chemical information in a quantitative context, most notably showing that despite the extreme intensities of salt material in the SIMS data, carbon is the main element throughout both IDIDs. Together the techniques show in general the more functionalized chemistries are at the deposit surface, with underlying salt layers and innermost layers of more amorphous organic material. These techniques represent a new method of comprehensive IDID characterization that affords diagnostic chemical information alongside elemental quantification, thus complementing previous studies.</div></div>

Reconsideration of regulated contamination limits to improve filterability of biodiesel and blends with diesel fuels

Abstract For the fulfillment of the Directive EU/2001/2018 targets for 2030, one of the main restrictions in the development of biodiesel fuels from sustainable feedstocks are currently the filterability problems. Contaminants such as saturated monoglycerides, sodium soaps and free steryl glucosides in biodiesel fuels have been found to clog fuel filters in vehicles, fuel dispensers and other industrial equipment which reduces the lifetime of the filters, and may result in fuel starvation, with engine operating difficulties and possible fuel-injection equipment damage. From a distilled biodiesel fuel spiked with these contaminants and subsequently blended with diesel fuel, samples fulfilling quality standards were prepared. filter blocking tendency, cold soak filtration test and total contamination tests were measured. It was found that filterability properties were affected always by the highest contaminant contents, both individually and synergistically. Total contamination test presented inconclusive results. The following conclusions were achieved: i) improvements in the precision of filterability and total contamination methods should be searched; ii) future regulations of biodiesel fuels should limit the free steryl-glucoside, saturated monoglyceride and sodium soap contents; iii) the current biodiesel fuel standards around the world do not secure the filterability properties, which could cause premature fuel filter clogging.