Diesel Engine Lubricating Oil Research Articles

Analysis and optimization of abnormal noise in lubricating oil circuit of diesel engine

Engine abnormal noise is one of the common engine faults, which will affect the comfort, power and safety of the automobile at the same time. In order to study the abnormal noise existing in the test process of diesel engine lubricating oil circuit system, 1D numerical simulation analysis of its flow field is carried out by using simulation software GT-power to verify the boundary conditions of the model and analyze the fluctuation of pressure at different speeds and temperatures. Through numerical analysis, it is found that there is almost no pressure fluctuation in the lubrication system before the pressure limiting valve is opened, but after the pressure limiting valve is opened, pressure fluctuation occurs in the pipeline, and the pressure fluctuation is different at different positions. Finally, the lubrication pipeline is simulated and analyzed by Pumplinx software, and the pressure fluctuation in the lubrication pipeline of diesel engine is reduced by optimizing the diameter of the oil pipeline and increasing the cavity structure.

Study on low temperature starting strategy for high power density diesel engines

During low-temperature starting, the high viscosity and poor fluidity of diesel engine lubricating oil make it difficult to be timely replenished to the friction pair, leading to the problems of starting difficulties and wear during cold starting. To address this issue, this study completed a simulation verification work through a bench test, and carried out a transient simulation of lubricating system oil filling in the range of 1–5 s starting time and −20°C to 80°C lubricating oil temperature to obtain the transient filling characteristics of the lubrication system oil path and the friction characteristics of the bearing. The results show that extending the starting time can effectively reduce the average dry sliding speed of the bearing, thereby reducing the frictional wear of the critical friction pairs during starting; when the oil temperature is between 20°C and 30°C, the average dry sliding speed of the bearing is low and the dry sliding distance is the shortest. The research results of this study are conducive to in-depth analysis of the lubrication oil filling mechanism during cold starting, and to determine a reasonable cold starting strategy from the perspective of lubrication.

Physicochemical properties of soot in diesel engine lubricating oil: characterizations and impact on frictional characteristics

The study investigates the effects of the physicochemical properties of engine sump soot on the frictional characteristics of its contaminated engine oils. Moreover, the relationship between soot physicochemical properties and its frictional characteristics was also discussed. The results showed that the properties of the two kinds of lubricating oil (A, B) used in diesel engines affect the properties of engine sump soot (Soot-A, Soot-B), i.e. Soot-A showing smaller aggregate size, larger primary particle diameter, more disordered nanostructure, and higher functional content than those of Soot-B. For both soot particles, as the amount of soot particles added to the formula oil went up from 1 wt.% to 2 wt.%, the wear scar diameter (WSD) and friction coefficient of the wear spot increased. For both soot particles, the main wear form of the steel ball wear area was abrasive wear (more than 90%), accompanied by a small amount of plastic deformation and pitting (less than 2%). With the same amount of soot in lubricating oil, soot with a higher degree of graphitization, low oxygen content and low reactivity may cause smaller WSD and lighter wear. Moreover, a larger soot accumulation would result in deeper plow marks and pits in the abrasion areas.

Purification control system of balanced charge lubricating oil based on PLC

Marine diesel engine lubricating oil after long-term use, due to pollution and chemical activity, internal impurities increased, lubrication effect gradually deteriorated. The lubricating oil purification device based on balanced charge agglomeration (BCA) can realize the on-line purification of lubricating oil. In order to further improve the purification efficiency, a purification control system based on PLC is designed in this paper. The system consists of a complex electromechanical integration equipment composed of oil purification equipment, PLC control equipment and touch screen. The precise control of control parameters is realized by PLC, which ensures the strict logical relationship between various steps of oil purification, and realizes the visualization and convenience of operation process. On this basis, the safety of the device is also guaranteed. Purification device in the actual operation, smooth operation, stable performance, high reliability.

Effects of Biomass Fast Pyrolysis Fuel on the Tribological Behaviour of Heavy-Duty Diesel Engine Lubricating Oil

The fuel type not only influences the engine power and exhaust emissions, but dilutes the lubricating oil. We studied the effects of biomass fast pyrolysis fuel, or biofuel, on the tribological behaviour of a fully formulated engine oil (FFEO) used for heavy-duty diesel engines by reciprocating a sliding tribometer, which simulated the tribological conditions of an engine cylinder liner and piston ring. We analysed the surface morphology, surface roughness, and elemental contents of countersurfaces through scanning electron microscopy/energy dispersant spectroscopy and surface roughness measurements. The wear mechanism was studied by analysing the compositions and kinematic viscosities of the oil samples. The results indicate that the friction coefficient increased along with the emulsified biomass fuel (EBF) content in FFEO. The wear mass loss and EBF content were simultaneously increased. The wear mechanism was mainly attributed to the corrosion function of the biofuel.

Monitoring Fuel Dilution of Diesel Engine Lubricant Oil by Ultraviolet Fluorescence Spectroscopy

Fuel contamination is a common problem in lubricating oil contamination. Generally, methods such as gas chromatography can be used, but the experimental process is more complicated. Fluorescence spectroscopy analysis has the advantages of fast detection speed and high sensitivity. Applying it to fuel dilution analysis can simplify the analysis process and enable rapid and accurate quantitative analysis. A certain type of fluorescence spectrophotometer was used to analyze and monitor lubricating oil containing different proportions of diesel oil. The fluorescence sensitive band was found, and the corresponding relationship between different lubricating oil content and the height and peak area of the fluorescence characteristic peak was analyzed.

The Influence of NaCl dissolved on biodiesel of used cooking oil on performance and its degradation of main components of diesel engine

Biodiesel has been developed both domestically and abroad. Various studies have been conducted to determine the feasibility and capability of raw materials used cooking oil is replacing diesel oil in the future. The salt content in the raw material for biodiesel (new cooking oil and used cooking oil) could have a negative impact or even do not have a significant effect on the rate of wear of metal on the main components of the diesel engine. Through durability tests, the effect of salt (NaCl) on the main components of diesel engines has been tested. The new cooking oil biodiesel is used as a reference in examining the damage level of the main components of diesel engines. Results of the experiments showed that there is a difference between the use of biodiesel fuel from used cooking oil with new cooking oil such as lower diesel engine performance, carbon deposits generated higher, and degradation of metal elements on the main component in the diesel engine lubricating oil is higher

Analysis of Diesel Engine Components Durability on Fishing Vessel Fueled with Biodiesel (B30)

The Indonesian government's policy of using biodiesel as an alternative fuel in the shipping industry is still an intensive discussion. Biodiesel as a substitute for diesel fuel has an impact on engine performance, lifetime and emission. The use of biodiesel fuel will increase the wear rate on metal components in diesel engines. From a series of tests carried out in accordance with Engine Manufacturer Association (EMA) standards, wearing on several engine components would be increase when the engine run using biodiesel palm oil (B30). The results showed that there was 19.8% aluminum content, 0.75% iron content, and chromium content in diesel engine lubricating oil with B30 biodiesel fuel higher than using diesel fuel. In addition, the clerance in the pisthon ring also increases and wear is seen on the journal bearing. However, the deposits formation in the diesel engine components made from palm oil biodiesel B30 is 5.43% increase than diesel fuel. From these results, it may be concluded that using of B30 palm oil biodiesel as fuel reduce durability of diesel engine standart.

Fluorescence enhanced microfluidic sensor with CsPbI3 probe for lubricant copper ions on-site rapid detection based on SiO2 inverse opal photonic crystals

Cu2+ content in diesel engine lubricating oil refers to a vital parameter suggesting the quality of oil and judging mechanical wear. Accordingly, the on-site rapid copper ions content determination in lubricant is of great significance to safe operation of diesel engines. However, most of the current researches on detection are carried out in laboratory, requiring the use of large-scale equipment such as spectrometer, which are not suitable for rapid on-site detection. Quantum dot-based optical microfluidic chip provides the possibility for heavy metal ions on-site detection, but it is subject to the defect of weak fluorescence intensity, thereby the increase in sensitivity is limited. In the present study, a microfluidic sensor using SiO2 inverse opal photonic crystals (IOPCs) to heighten CsPbI3 perovskite quantum dots (PQDs) photoluminescence (PL) intensity is proposed, which can realize rapid Cu2+ content detection in lubricant. Firstly, the selective detection characteristic of CsPbI3 on Cu2+ was studied. Experimental results showed that the photoluminescence of CsPbI3 was significantly quenched by Cu2+ because electrons were effectively transferred from CsPbI3 to Cu2+. Subsequently, to enhance the fluorescence intensity of CsPbI3 probe, the SiO2 IOPCs structure was formed in chip detection well. The effective PL intensity of CsPbI3 PQDs was enhanced by the photonic stopband effect formed by the periodically arranged micro-nano structure of photonic crystals. This enhancement effect was attributed to the coupling effect between stopband with excitation and emission light. As the stopband of SiO2 IOPCs was coupled with the excitation light wavelength and emission light wavelength of CsPbI3, the enhancement factors could reach 17-fold and 22-fold, respectively. The mentioned strategy could effectively improve the detection sensitivity of the microfluidic sensor and reduce the detection limit to 0.34 nM. Moreover, the formed microfluidic sensor system can be used for determination of Cu2+ content in lubricating oil on site. Meanwhile, the sturdy porous structure of SiO2 IOPCs also facilitated target metal ions to be captured and enriched.

Research on FT-IR spectrum data mining of diesel engine lubricating oil

Aiming at the difficulties in quantitatively describing the pollution component information contained in FT-IR spectral data of diesel engine lubricants, wavelet transform and fractal box dimension are used to process FT-IR spectral data and get fractal dimension curve. Multiple peaks can be obtained by analyzing the curve. Two groups of lubricating oil samples with water content of 0.10%, 0.22%, 0.44% and 0.88% respectively and with ethylene glycol content of 0.10%, 0.22%, 0.44% and 0.88% respectively. For the above two groups of oil samples, the corresponding relation between peak position and contaminate ratio can be obtained, and a new method based on FT-IR prediction of contaminate ratio is feasible.

The effect of use of biodiesel B30 from palm oil to degradation of oil lubrication in 1-cylinder diesel engine 4-stroke

New alternative fuels are needed to reduce the fossil fuels. Biodiesel from palm oil is one alternative fuel to replace fossil fuel. This is because Indonesia is the largest producer of palm oil in the world. There are several analyzes that the use of palm oil causes a significant decrease in the viscosity of lubricating oil. A research is carried out to evaluate the effect of B30 biodiesel from palm oil on the degradation of diesel engine lubricating oil. The method used is experiment with testing diesel engines endurance referring to the standards of the Engine Manufacture Association (EMA) to determine differences in lubrication degradation. As a result, B30 biodiesel from palm oil causes greater degradation in lubricating oil than using Dexlite diesel fuel. Biodiesel B30 causes lubricating oil to decrease its viscosity by 46.98%, increase the viscosity index by 7.84%, increase in the flash point, increase in the pour point some 3°C and decrease in the base number by 4.62% and 3.6026% less water content.

Fuel adhesion and oil splash on oil-wet cylinder walls with post diesel fuel injections

Diesel particulate filters are used to capture the particulate matter in engine exhaust, and the post fuel is injected for a regular regeneration of the diesel particulate filter to avoid plugging of the diesel particulate filter with the particulate matter. The concept of the post fuel injection is as follows: the post fuel is injected in the expansion stroke, the vaporized fuel gas is oxidized by the diesel oxidation catalyst, here the high temperature gas oxidizes the particulate matter on the diesel particulate filter, and the diesel particulate filter is regenerated. However, the post fuel impinges and adheres on the cylinder wall due to the low temperature and pressure conditions in the expansion stroke in actual engine operation and this causes diesel engine lubricant oil dilution, the deterioration of fuel consumption characteristics in diesel engines, as well as ash plugging of the diesel particulate filter. In this article, the post fuel spray behavior and adhesion on oil-wet cylinder liners were investigated with a high pressure–temperature optical constant volume chamber instead of engine tests. The in-cylinder temperature and pressure at the 30, 60, and 90 °CA after top dead center, commonly employed in post fuel injection timings, were measured in engine operation. To create the post fuel injection conditions of diesel engines in the constant volume chamber, pre-mixed gas containing ethylene, oxygen, and nitrogen is introduced into the chamber and ignited by the spark plug. Then, fuel masses of 0.5, 1.0, and 1.5 mg per injection hole at the after top dead center settings were injected to a wall adhesion plate with a 5-μm thick oil film that simulates the surface of the cylinder liner and the post fuel impinges on and splashes oil away from the oil film on the cylinder wall. The quantities of splashed oil and adhering fuel on the wall adhesion plate were measured by a precision balance and a thermostatic chamber. With the early post injection, most of the injected fuel vaporizes without penetrating to the cylinder liner and gaseous diesel fuel is condensed on the cylinder wall; however, with the late post fuel injections, the strong penetration of liquid fuel reaches the cylinder wall, and much engine oil becomes splashed away. The droplet size of the fuel spray was measured by telescope ultra-high resolution image analysis with a digital single-lens reflex camera, and the fuel impingement phenomena on the cylinder wall are explained by the Weber number, calculated from velocity and diameter values, droplet density, and surface tension.

Measurements of fuel adhesion on cylinder walls and fuel wall-flow behavior with post diesel fuel injections

Post fuel injection in the expansion stroke is used for diesel particulate filter regeneration; however, fuel spray impinges on the cylinder liner due to the low temperature and pressure conditions. Fuel adhesion and fuel flowing down across the cylinder liner, the so-called “wall-flow,” was observed by high-speed video images, and this adhesion is a cause of diesel engine lubricant oil dilution and the deterioration of fuel consumption in diesel engines. In this article, the fuel adhesion and the wall-flow of post diesel fuel injections were investigated with a high pressure-temperature constant volume optical chamber. The in-cylinder temperatures and pressures at 30, 60, and 90 °CA ATDCs, conditions commonly employed in post fuel injection timings, were measured by an actual engine, and similar conditions were created in the constant volume chamber by the combustion of a pre-mixed gas of ethylene, oxygen, and nitrogen. Fuel masses of 0.6, 1.1, and 1.7 mg per hole were injected at each ATDC setting. The weight of the adhered fuel on the wall and the fuel in the piston-cylinder crevice were measured by precision balance, and the liquid–vapor phases in the spray were observed by Mie scattering and shadowgraph methods. To measure the thickness of the adhered fuel on the cylinder wall, the laser-induced fluorescence method was employed. The results show that the fuel spray penetration and adhesion on the cylinder wall were different in the test conditions investigated here. With the early post injection, most of the injected fuel vaporizes without penetrating to the cylinder liner and gaseous diesel fuel is condensed on the cylinder wall. A thin and widely spread out fuel film is formed on the cylinder wall; however, no wall-flow could be confirmed by the high-speed video images. With late post fuel injections, the strong penetration of liquid fuel reaches the cylinder wall, and a thick and widely spread out fuel film was formed on the cylinder wall and the wall-flow phenomenon was observed here. However, the quantity of fuel involved in the wall-flow was smaller than that of the fuel adhering to the cylinder wall. The effects of in-cylinder pressure and temperature on the fuel adhesion on the cylinder wall were investigated. With the increase in pressure and temperature, the quantity of adhering fuel was reduced, suggesting that the boost pressure increase by turbo charging and a higher engine load is effective to reduce fuel adhesion. Furthermore, the effects of multiple post fuel injections on fuel adhesion to the cylinder wall were investigated, maintaining the total fuel injection amounts. With increases in the number of fuel injections, the total percentage of adhering post fuel on the cylinder wall was reduced. In the multiple fuel injections, it was observed that fuel motion takes place during the spray pass after the first and second fuel injections and that the penetration length of the second and third fuel sprays increases.

Physical properties improvement of the diesel engine lubricant oil reinforced nanomaterials

Physical properties improvement of the diesel engine lubricant oil reinforced nanomaterials

Importance of Emulsification in Calibrating Infrared Spectroscopes for Analyzing Water Contamination in Used or In-Service Engine Oil

Using Fourier transform infrared (FT-IR) spectroscopy we investigated the water content of SAE 15W–40 diesel engine lubricating oil at various levels of contamination to establish instrument calibration standards for measuring water contamination in used or in-service engine oil by the standards of ASTM International. Since some known additives in consumer grade engine oil possess slightly hydrophilic properties, this experiment avoided changing the sample matrix with supplemental additives, such as adding surfactants, to achieve homogeneity of the original sample. The impact of sampling time after contamination on the spectral absorption signature was examined in an attempt to improve the accuracy of water contamination quantification and determine if water-soluble potassium bromide (KBr) windows were suitable for analyzing water in oil emulsions. Analysis of variance (ANOVA) modeling and limit of detection calculations were used to predict the ability to discriminate contamination levels over time. Our results revealed that the amount of water concentration in engine oil could be misinterpreted depending on the timing of the FT-IR measurement of the calibration standard after initial water contamination. Also, KBr windows are not sufficiently etched due to the limited window interaction with water molecules within micelles of emulsions to alter FT-IR spectral signatures.

Optimization of the multivariate calibration of a Vis–NIR sensor for the on-line monitoring of marine diesel engine lubricating oil by variable selection methods

This paper deals with the description of the optimization by variable selection methods of the multivariate calibration process of a low-cost Visible–Near Infrared (400–1100nm) sensor, developed for the on-line monitoring of the insoluble content in diesel marine engine lubricating oil. The performance of the calibration model developed for the Vis–NIR sensor was compared with the performance of the calibration model developed with spectra obtained with a UV/Vis–NIR laboratory spectrometer. The calibration results obtained with the two devices were compared to determine the limitations of the sensor system with respect to the laboratory equipment. First, the spectra were correlated with the insoluble content analyzed in Wearcheckiberica's oil laboratories obtaining a calibration model based on Partial Least Squares-regression (PLSR). Once the pre-processing strategy had been defined, the most significant predictor variables were chosen with the help of Martens uncertainty test, interval Partial Least Squares (iPLS) and Genetic Algorithms (GA) variable selection techniques. Finally, the two models were compared based on the number of latent variables of each model of the values of the Root Mean Square Error of the Cross Validation (RMSECV), the Standard Error of Performance (SECV) and the Ratio of Prediction to Deviation (RPD).

Application of Acoustic Emission Technique to Monitor the Viscosity of Single Grade Diesel Engine Lubricant Oil

This paper presents an investigation of the capability of the acoustic emission (AE) technology in the processes of monitoring and detecting the variation of diesel engine lubricant viscosity via in-situ operation. The investigations were conducted on an 8.5-hp single cylinder of four strokes with a water cooling diesel engine. One single grade engine lubricant oil condition has been put to the test; namely, SAE 40. The lubrication condition in the diesel engine was successfully monitored based on the AE signatures generated by the interaction between the piston surface and the layer of the lubricant during the time that the engine was in operation. The generated AE signatures were captured using an AE wide band transducer that was bonded outside the engine block and located at the lower part of the bottom dead centre (BDC). The captured waveform signatures were then analysed using the MATLAB software. The results of the experimental works show that the statistical analysis parameters including the root-mean-square (rms), maximum amplitude and AE energy values are capable of distinguishing the variant of the viscosity. The AE technique can assist the owner of the diesel engine in determining the diesel engine lubricant oil condition before replacing it.

Application of Symbolic Regression to Electrochemical Impedance Spectroscopy Data for Lubricating Oil Health Evaluation

The authors have applied an advanced set of auto-regressive tools for identifying potentially complex, linear and non-linear relationships in data, wherein the underlying physical relationships are not well described. In this paper these tools and techniques are described in detail, and the results of the application of these tools to evaluation of diesel engine lubricating oil health (based on electrochemical impedance spectroscopy data) is detailed. It is demonstrated that highly accurate models can be constructed which take as input features derived from diesel engine lubricating oil electrochemical impedance spectroscopy data and output estimates of traditional laboratory based oil analysis parameters. The electrochemical impedance spectroscopy and laboratory analytical data used are from a field deployment of oil condition sensors on several long-haul class 8 diesel trucks. The dataset was divided into training and test datasets and goodness of fit metrics were calculated to evaluate model performance. Models were successfully generated for nitration, soot content, total base number, total acid number, and viscosity.

Research of Marine Diesel Engine’s State Prediction Based on Evolutionary Neural Network and Spectrometric Analysis

In this paper, an evolutionary neural networks model is proposed to predict the content of metal elements contained in marine diesel engine lubricating oil, by fusing genetic algorithms (GAs) and error back propagation neural network (BPNN) to offset the demerits of one paradigm by the merits of another. The input data of metal content was detected by spectrometric analysis. Genetic algorithms are used to globally optimize the weights and threshold of BP neural networks. Moreover, one case study was presented to illustrate the proposed method. The prediction accuracy of the novel method is compared with that of only BPNN method to illustrate the feasibility and effectiveness of the proposed method. The relative error on average of results is 1.52%, it can meet the precision request of state detecting in marine diesel engine.

The effect of palm oil diesel fuel contaminated lubricant on sliding wear of cast irons against mild steel

The effect of various percentages of palm oil diesel (POD) fuel contaminated lubricants on the wear characteristics of cast irons during sliding contact was investigated. This was done on three types of cast iron, namely spheroidal graphite, flake graphite and chilled cast iron against a mild steel disc configuration using a pin-on-disc type of friction and wear apparatus. The lubricants used for the test specimen were Mach 5 SAE 40 with various percentages of POD. For comparison purposes, pure diesel engine lubricant oil and pure palm oil diesel were also used as lubricants. The test conditions were as follows: pressure, 1 MPa; sliding speed, 0.2 m s −1; sliding distance, 56 km; room temperature, ∼30°C. It was observed that the addition of 5% palm oil diesel into the engine lubricant improves the performance of the lubricant in terms of anti-wear characteristics, reducing the wear rate of cast irons. The use of pure commercial (0% POD contamination) lubricant resulted in a moderate wear rate, whilst pure POD (100%) lubricant produced the highest wear rate compared with the other combinations of contaminated lubricants.