Lubricating Oil Consumption Research Articles

Effect of piston ring geometries on lubrication and friction in diesel engine

Lubrication and friction in piston rings are of a greater importance which has been receiving significant attention from tribologists for a long time. The main subsystems which contribute to friction include the ring-pack/liner, piston-skirt/liner, piston-pin/connecting-rod and connecting rod-crankshaft bearings. Piston rings are used in engines mainly to reduce leakage of gas in the combustion chamber and simultaneously provide a lubrication film in order to reduce friction during its motion. Wear between piston rings and liner is inevitable and therefore in order to reduce it, different types of ring geometries are being used which has its own advantages and disadvantages. Another major problem being faced during operation is that oil from the liner gets transported by pumping, reverse blow by, inertia and squeezing of oil due to ring dynamics into the combustion chamber. The present work focuses on to investigate different ring geometries and their effects on friction and lubrication oil consumption. It was found that Tangential force has an inverse relationship with Oil Film Thickness and Oil filling ratio. Top ring friction is high at Top dead centres due to boundary lubrication. Ring Barrel height has a direct relationship with asperity friction and an inverse relationship with Oil Film Thickness. Axial width is directly proportional to the wear of rings, which is due to the area exposed to back pressure on the rings exerted by gases from combustion chamber. Second ring closed gap has a direct relationship with Inter-ring pressure thus increasing reverse blowby. Rings with a Positive twist are found to be stable during operation. For this analysis, AVL Excite software is being used and results are validated with an experimental model.

Feasibility study of diesel engine replacement on passenger ships: a system dynamics approach

As an archipelagic country, passenger ships are used as the inter-island transportation mode. PT. PELNI is one of the shipping line companies operating some passenger vessels in Indonesia. As the total time of ship operated is getting high, the main engine will be slowly deteriorating. This paper took three ships with varied age of ship, namely KM Gunung Dempo, KM Labobar, and KM Dobonsolo, owned by PT. PELNI as the case studies for analyzing the age determination of ship diesel engine replacement using system dynamics (SD) approach. System dynamics has become one of the most frequently used approach to deal with a decision-making problem for a complex system. There are two major variables considered here, operational expenditures (OPEX) and capital expenditures (CAPEX). CAPEX consists of docking cost for engine replacement, purchasing the dual-fuel engine and liquefied natural gas (LNG) ISO tanks procurement, and cost that caused by the conversion of the cargo spaces into the LNG storage tanks. OPEX variable consists of all costs that related to the operations of the ship, such as fuel oil (FO) consumption, lubricating oil consumption, maintenance cost, and engine overhaul cost. These two variables, CAPEX and OPEX, represent the difference between conventional diesel engine and dual-fuel diesel engine. There were 18 scenarios applied to each ship with variations of LNG price, FO price, and the maintenance cost. The result shows that 14 scenarios are categorized under feasible scenario for KM Dobonsolo with the average profitable life of 2.22 years; 17 feasible scenarios for KM Labobar and 16 scenarios are feasible for KM Gunung Dempo with the average profitable life of 11.72 years and 15.17 years.

Experimental investigations of ethanol blended biodiesel fuel on automotive diesel engine performance, emission and durability characteristics

500 h durability, performance and emission tests are conducted on a single cylinder high speed automotive diesel engine for the ethanol blended biodiesel fuel. Esterified cotton seed methyl ester of 5% by volume is mixed with 95% neat diesel to obtain the base biodiesel fuel (B5). The base fuel is mixed with 20% pure ethanol to derive the ethanol blended biodiesel fuel (B5E20). The parameters like blow-by, crank case pressure and lubricating oil consumption are experimentally investigated along with performance and emission characteristics for both the test fuelled engines. The result of these tests showed a significant loss in maximum brake power and maximum brake torque at the end of 500 h durability run when the engine is fuelled with B5E20. The lubricating oil consumption and positive crank pressure of B5E20 fuelled engine is comparatively higher than B5 fuelled engine during the durability trials. Reduction in smoke and CO emissions are noticed for B5E20 fuel over the entire range of speed whereas NOX and unburned hydro carbon emissions get decreased at lower to medium speed range and increases thereafter. As expected, all the engine emissions increase after 500 h of durability run for both the fuels.

An analysis of energy flow in a turbocharged diesel engine of a heavy truck and potentials of improving fuel economy and reducing exhaust emissions

The impetus of the internal combustion engine developments is the reductions of the fuel consumptions and exhaust emissions. Thermal management is an efficient method to decrease the exhaust emissions and enhance fuel economy. In order to further optimize the thermal management of internal combustion engines, a detailed analysis of the energy flow in each component of internal combustion engines is indispensable. In this paper, the test bench of a heavy duty diesel engine was established to obtain the target parameters. The energy distributions in each component of the diesel engine, including compressor, intercooler, shaft power, turbine, coolant and exhaust, were calculated using tested parameters. The lubricating oil consumption was also taken into consideration. In addition, the potential influences of different turbochargers on the total thermal efficiency were analyzed. The results showed that the thermal efficiency of the diesel engine was more than 38% when the engine operated at 50%–100% engine load and 1000 rpm–1700 rpm conditions. The energy loss by coolant was more than 50% of the total fuel energy consumption in the low power output conditions. However, it was lower than 30% in high power output conditions, and the thermal loss was more than 150 kW around rated power conditions. The maximum proportion of the energy being consumed by turbine was ∼10% of the fuel energy; additionally, the exhaust energy distributions changed significantly after the turbine expansion. 1%–3% of the fuel energy was recycled by the turbocharger, then, flowed into the cylinders. The energy loss through the intercooler accounted for ∼6% of the fuel energy. Significant reductions of exhaust emissions and fuel consumptions can be achieved by optimizing the coolant and lubricating oil thermal conditions. Turbochargers presented a huge effect on exhaust temperature distributions at high power output conditions, and the total thermal efficiency changed significantly if all kinds of energy recovery approaches were applied.

Estimating the Total Lubricant Oil Consumption Rate in Agricultural Tractors

Abstract. Lubrication effectiveness is of paramount importance for the durability of machine components and efficient transmission of power. In addition to reducing the wear and friction of moving parts, lubricants remove potentially damaging heat and impurities and reduce the oxidation and corrosion of components. In agricultural tractors, lubricant oils are used in the engine, transmission, hydraulic system, front and rear axles, steering, and braking systems. This means that a substantial amount of oil must be changed at regular intervals, as recommended by manufacturers. This leads to a significant total oil consumption rate whose estimation is related to accurate accounting of tractor operating costs and to environmental impact analysis (e.g., LCA) of mechanized agricultural operations. The objective of this study was to propose a new general equation to estimate the total hourly lubricant oil consumption rate (HTOC) of agricultural tractors as a function of the rated engine power by extending the definition of lubricant oil consumption rate given by ASABE Standard D497.7. To this end, a linear regression analysis was conducted on a training dataset of 91 tractor models retrieved from OECD Code 2 reports. After validation with a dataset of 164 tractor models, the resulting equation for estimating the total lubricant oil consumption had an R2 = 0.75 and prediction RMSE of 0.033 kg h-1. The equation was finally applied to an independent dataset of actual oil lubricant consumption rates obtained from a field survey of 118 agricultural tractors operating in northern Italy. Application of the equation to the field survey data showed an R2 of 0.89 and RMSE of 0.010 kg h-1 between predicted and actual values. Overall, the considered statistical indicators (r, R2, RMSE, PBIAS, and NSE) pointed to a satisfactory prediction capability of the equation. Keywords: Agricultural tractors, Lubricant oil, Oil consumption, Mechanization costs.

A Study on Piston Ring Conformability to Cylinder Bore Influencing on Lubricating Oil Consumption

A Study on Piston Ring Conformability to Cylinder Bore Influencing on Lubricating Oil Consumption

Influence of the Position of Oil Drain Holes of a Piston on Lubricating Oil Consumption

An increase in lubricating oil consumption in a gasoline engine causes an increase in particulate matters in exhaust gases, poisoning the catalyst after treatment devices, abnormal combustion in a turbo-charged gasoline engine, and so on. Recent trend of low friction of a piston and piston ring tends to increase in lubricating oil consumption. Therefore, reducing oil consumption is required strongly. In this study, the effect of the position of oil drain holes on oil pressure under the oil ring and lubricating oil consumption was investigated. The oil pressure under the oil ring is measured using fiber optic pressure sensors and pressure generation mechanisms were investigated. Lubricating oil consumption was also measured using sulfur tracer method and the effects of oil drain holes hence the oil pressure were evaluated. Four types of arrangement of oil drain holes were tested. The oil pressure variations under the oil ring in the circumferential direction was measured. An increase in oil pressure was found during down-stroke of the piston. The lowest oil pressure was found for the piston with four oil drain holes. Two holes nearby the front/rear end of the piston skirt showed relatively lower pressure. The measured results of oil consumption showed good agreement to measured oil pressure under the oil ring. It was found that oil pressure under the oil ring affected oil consumption, and oil drain holes set near the front/rear end of the piston skirt were effective for reducing oil consumption.

Cylinder Head Bolts Tightening Strategies Parameters Finalization by Taguchi Method for Multi Cylinder Engines

The Cylinder head gasket (CHG) joint is the most important sealing joint for IC engine performance. Cylinder head bolt preload application should be stoichiometric. Excess cylinder head bolt pre-tension develops more stresses and extra bore deformation and insufficient cylinder head bolt pre-tension leads to gasket leakage. Uniform pressure distribution is required on cylinder head gasket but it is not possible because of varying stiffness of the head and block. Hence maximum pressure distribution is better for avoiding the leakages. Bore deformation, engine blow-by and lubricating oil consumption (LOC) of the engine minimum is better for achieving stringent emission norms. Influences of application method of preload, cylinder head bolt tightening pattern and number of passes are investigated on gasket pressure distribution, bore deformation, engine blow-by and LOC. FEA non-linear analysis is carried out for gasket pressure distribution and bore deformation. Piston and piston ring software is used for simulating engine blow-by and LOC. For optimizing controllable parameters Taguchi design of experiments method is used for robust and optimized design. Study reveals that tightening parameters influences are significant. This study is very important for IC engine efficiency improvement and engine CO2 emission reduction at design stage for new engine development program.

Life cycle assessment of concrete paving blocks using electric arc furnace slag as natural coarse aggregate substitute

Abstract This study assessed the environmental impacts of natural coarse aggregate and electric arc furnace aggregate production, and the impacts of paving blocks production using both aggregates in the proportion of 50%. The life cycle impact assessment has been performed by using the IMPACT 2002 + method, considering the impact categories of carcinogens, non-carcinogens, respiratory inorganics, terrestrial ecotoxicity, global warming and non-renewable energy. In the electric arc furnace aggregate production, the results indicate that metal recovering is responsible for the negative impacts (84%); electricity, diesel and lubricating oil consumption contribute for respiratory inorganics, global warming, non-renewable energy and non-carcinogens impact categories, while transport contributes for the same categories and terrestrial ecotoxicity. Considering the paving blocks production, cement has the highest contribution for all impact categories, except terrestrial ecotoxicity; the paving blocks produced with electric arc furnace aggregate present the lowest impacts for the climate change and ecosystem quality categories, and avoided impacts for human health and resources damage categories.

Predicting Microscale Cross-Hatched Surface Texture in Engine Cylinder Bore

Cross-hatched texture is the essential surface feature in cylinder bore generated from honing process. The interconnected grooves of the surface texture provide storage space and diffusion channels for the lubrication oil. Thus, it is widely used to reduce contact friction, lubrication oil consumption and improve the wear resistance of piston-ring contact pairs in automotive engine. The surface texture was simulated by various analytical methods in literatures. However, the mechanism of generation of surface texture stays a black box and poses a challenge to further control engine quality. This study presents a new kinematic model to simulate the generation of cross-hatched surface texture in the honing process of engine cylinder bore. It formulates the process motions based on honing operations in automotive industry. And a microscale model is established to simulate honing stone surface topography with randomly distributed abrasive particle sizes, postures and distributions obtained by a modified Poisson disk sampling algorithm. The kinematic simulation is performed by moving the honing stone surface topography along the motion trajectory. Abrasive particles interact with cylinder surface and generate texture grooves as honing stones feed. Using this method, honing surface texture is demonstrated with cross-hatched feature at microscale level, and the difference of cross-hatched texture is revealed visibly and quantitively as roughness corresponding to honing stones with different abrasive particle shapes, wear conditions and position distributions in height direction.

Cost reduction by value stream mapping using Lean-Kaizen concept: a case study

Small and medium scale enterprises (SMEs) are under consistent pressure for improving the product quality in order to meet the customer requirements. The present case demonstrates the application of Lean-Kaizen concept using value stream mapping (VSM) for eliminating waste. Based on data collected from Shaft Swing Arm, current and future state maps have been constructed. The high rejection rate and increased lubrication oil consumption are identified as waste. Two Kaizen events; first, the high rejection rate is fixed by modifying the existing process route and second, the high consumption of lubrication oil is controlled by installing the new pipeline in the machine, have been proposed as solutions. A significant cost reduction of 7.50 lacs INR per year is recorded. Lean-Kaizen using VSM is found an effective technique to reduce the cost. The methodology will be beneficial for the managers and researchers to tackle various inefficiencies in the SMEs.

Study on Lubricating Oil Consumption from Evaporation of Oil-Film on Cylinder Wall for Diesel Engine

Study on Lubricating Oil Consumption from Evaporation of Oil-Film on Cylinder Wall for Diesel Engine

Effective test of lacquer in marine diesel engines

We perform an experiment on lacquer formation with simple test device. The anti-lacquer is one of important issues to increase durability, and to improve performance in the engines because the lacquer formation cause sticking of fuel injection pump, scuffing of cylinder liners, and increase of lubricant oil consumption in the marine diesel engines. We suggest this simple test in order to save enormous experimental cost in marine diesel engines, and in order to have ease in performing the various tests. The influences of the Base Number (BN) of lubricant oils and the sulfur content of fuel oils in the formation of lacquer are investigated. In order to investigate physical and chemical properties of lacquer, we perform a variety of tests such as, visual inspection, EDS. In addition, we investigate adhesion of lacquer by pull-off test quantitatively, and perform dissolution test with dilute sulfuric acid.

Changes in performance and wear of small diesel engine during durability test

Changes in engine performance and efficiency, the tightness of ring-pack and wear of piston group parts during long-lasting bench durability test were investigated. The tests were conducted on 2 modern automotive diesel engines. The parameters analysed improved in the initial period of engine operation and then they started to deteriorate gradually; however, the rates of change were different for different parameters. The rate of change was the highest in the case of lubricating oil consumption (100% increase during the test). The blowby increased in that period of time by 25-60%, depending on the condition of engine operation. The changes in power and specific fuel consumption were much smaller – only a few percent. Moreover, using the previously developed method utilizing the simulations made with the use of the ring-pack model, the durability of the piston group was predicted. The predicted durability was equal to 300,000 km.

DESIGN OF PISTON RING SURFACE TREATMENT FOR REDUCING LUBRICATING OIL CONSUMPTION

The reduction of lubricating oil consumption in the internal combustion engines is important for clearing the emission standard and environmental problem, especially the hydrocarbon and particulate matter. Recently, it is reported that lubricating oil which exist near the piston ring or piston crown effects strongly for occurrence of pre-ignition in highly supercharged spark ignition engines. This paper describes results of a study on the mechanism of lubricating oil consumption from the top ring with piston motion. The experimental and calculated data show that it is effective the surface treatment of piston ring to reduce lubricating oil consumption. The wetting angle on the piston ring and the viscosity of the lubricant oil are key parameters for lubricating oil consumption from the top ring.

A Study on the Effect of Third Land Pressure on Lubricating Oil Consumption of a Gasoline Engine

A Study on the Effect of Third Land Pressure on Lubricating Oil Consumption of a Gasoline Engine

The Effect of Cylinder Bore Distortion on Lube Oil Consumption and Blow-By

It is well known that cylinder bore deformations during engine operation cause a number of problems in piston ring lubrication. Particularly, the deterioration of piston ring and cylinder bore conformability results in a significant increase in lubricating oil consumption. Therefore, measurement and identification of cylinder bore distortion has been an important subject for engine designers. In this study, an analytical lubricating oil consumption model was developed for a diesel engine. Piston stiffness was identified as an important input parameter for the oil consumption model, and the stiffness matrix of the piston was calculated using finite element simulations. In addition, finite element analysis was performed to determine the distorted cylinder block shape in engine running conditions. Pressure curves and loads obtained in actual engine tests were used in the analysis. The Fourier coefficients of a distorted cylinder bore was calculated which characterize the deformed bore orders. Using these Fourier coefficients, several distorted bore shapes were regenerated, including a straight bore and the effect of each order on total lube oil consumption was investigated by means of the oil consumption model.

Characterization and friction performances of Co–Al-layered double-metal hydroxides synthesized in the presence of dodecylsulfate

In this paper, Co–Al-layered double-metal hydroxides (CAD-LDHs) were synthesized by co-precipitation in the presence of dodecylsulfate (DDS) and characterized by XRD, FT-IR, TG–DSC, SEM. In addition, their frictional features were evaluated by four-ball friction tester, gear tester and air compressor. The results showed that synthesized CAD-LDHs have a hexagonal platelet morphology. Most crystallites have a disk diameter of around 150–250nm and a thickness of about 20nm, with a0=b0=0.31nm, c0=8.33nm, d-spacing=2.78nm and gallery height=2.30nm. The specific surface area is 78m2/g. DDS anions entered the interlayer of LDHs and were perpendicular to the LDH layer in a monolayer array. As a lubricant, CAD-LDH powder has excellent dispersability and suspension stability in the lubrication oil, and can significantly reduce friction coefficient (50.7%) and wear of friction pairs (17.9%). At the same time, they can reduce the temperature of lubrication oil (6.1%) and power consumption of driving motor (2.6–6.8%). Accordingly, CAD-LDHs may broadly be used as lubrication and anti-frictional materials.

Analysis of oil consumption in cylinder of diesel engine for optimization of piston rings

The performance and particulate emission of a diesel engine are affected by the consumption of lubricating oil. Most studies on oil consumption mechanism of the cylinder have been done by using the experimental method, however they are very costly. Therefore, it is very necessary to study oil consumption mechanism of the cylinder and obtain the accurate results by the calculation method. Firstly, four main modes of lubricating oil consumption in cylinder are analyzed and then the oil consumption rate under common working conditions are calculated for the four modes based on an engine. Then, the factors that affect the lubricating oil consumption such as working conditions, the second ring closed gap, the elastic force of the piston rings are also investigated for the four modes. The calculation results show that most of the lubricating oil is consumed by evaporation on the liner surface. Besides, there are three other findings: (1) The oil evaporation from the liner is determined by the working condition of an engine; (2) The increase of the ring closed gap reduces the oil blow through the top ring end gap but increases blow-by; (3) With the increase of the elastic force of the ring, both the left oil film thickness and the oil throw-off at the top ring decrease. The oil scraping of the piston top edge is consequently reduced while the friction loss between the rings and the liner increases. A neural network prediction model of the lubricating oil consumption in cylinder is established based on the BP neural network theory, and then the model is trained and validated. The main piston rings parameters which affect the oil consumption are optimized by using the BP neural network prediction model and the prediction accuracy of this BP neural network is within 8%, which is acceptable for normal engineering applications. The oil consumption is also measured experimentally. The relative errors of the calculated and experimental values are less than 10%, verifying the validity of the simulation results. Applying the established simulation model and the validated BP network model is able to generate numerical results with sufficient accuracy, which significantly reduces experimental work and provides guidance for the optimal design of the piston rings diesel engines.

System PHM Algorithm Maturation

The maturation of PHM functions is focused on two Key Performance Indicators (KPI): The NFF, No Fault Found ratio, P(No degradation|Detection), and the Probability Of Detection POD, P(Detection|Degradation). The estimation of the second KPI can be done by counting the global abnormality threshold trespassing when each different kind of degradation is simulated. The estimation of the first KPI can be done through the following formula using the Bayes rule:( )( | )* ( )( | )P DetectionP Detection NoDegradation P NoDegradationP NoDegradation Detection P(Degradation) may be known through FMEA or field experience. Typically, for a probability of 10-7, a specified NFF ratio of 1%, and an expected POD of 90%, the order of magnitude of P(Detection| No degradation) should be 10-9. The estimation of such extreme level of probability needs some parametric adjustment of the distribution of the global abnormality score with no degradation. Two PHM functions are considered as case studies: Turbofan engine start capability (ESC) and turbofan engine lubrication oil consumption (EOC). In ESC the global abnormality score is a norm of a vector of specific abnormality scores. The specific scores are centered and reduced residues between expected values and observed values. Some specific scores are devoted to starter air supply. Examples are duration of phase 1 from starter air valve open command to ignition speed. Other scores are devoted to fuel metering. Examples are duration of phase 2 from ignition to cut off speed. The expected values are estimations through regression relations using as inputs the other specific scores and context parameters such as lubrication oil temperature at start. The regression relations are learnt on start records with no degradations. Impact simulations of degradations on specific scores are learnt on a phase 1 simulator based on torques balance and on start test records including fuel metering biases. In EOC, the global abnormality score is the daily weekly or monthly consumption estimations on a daily basis. Consumption estimations use linear regressions of oil level measurements versus time at an invariable ground idle speed corrected according to oil fill detections and oil temperature. The over consumptions are simulated by drifts in mean of the consumption estimations.To reach acceptable POD at the specified NFF ratio three improvements are needed for ESC:  Adjust the abnormality decision threshold according to each candidate degradation using extreme value quantiles on the global abnormality score distribution Average the global abnormality score on five consecutive starts Learn the regression relations specifically on each engine.The first improvement is a novelty. It is successfully applied to both ESC and EOC functions. It is generic to all airborne system PHM functions based on abnormality scores.