Common Rail Research Articles

Comprehensive Analysis of Compression Ratio, Exhaust Gas Recirculation, and Pilot Fuel Injection in a Diesel Engine Fuelled with Tamarind Biodiesel

The global automotive industry is facing significant challenges, including dwindling fossil fuel reserves, rising crude oil prices, and increasingly strict emission regulations. To address these concerns, this study investigates the impact of the compression ratio (CR) and exhaust gas recirculation (EGR) on the performance and emissions of a common rail direct injection (CRDI) diesel engine fuelled with a 20% blend of tamarind seed methyl ester (TSME 20) biodiesel. The study employed an open-type electronic control unit to implement pilot fuel injection at a rate of 30%, 23° before the top dead centre (TDC), and at a higher pressure of 600 bar. Three CRs (16:1, 18:1, 20:1) and two types of EGR (hot and cold EGR at 10%) were evaluated. Diesel fuel at CR 18 was used as a baseline for comparison. The experimental procedure involved conducting tests with TSME 20 at CR 16, 18, and 20. Subsequently, TSME 20 at CR 20 + Hot EGR 10% and TSME 20 at CR 20 + Cold EGR 10% were examined. The results showed that TSME 20 operated at a higher CR (CR 20) exhibited improved diesel engine performance and significant reductions in harmful exhaust emissions. Additionally, cold EGR at 10% was more effective in reducing CO, CO2, and NOx emissions from TSME 20 than hot EGR. The findings of this study provide valuable insights into optimizing diesel engine operation to achieve a balance between performance enhancement and emission reduction through tamarind seed biodiesel blends and different EGR techniques. The implementation of these strategies holds considerable potential in addressing the automotive industry’s challenges, including ecological considerations and fuel price fluctuations.

Expanded statistical analysis of squats on the Great Britain (GB) mainline network

Squat defects are one of the most common rail surface defects. Significant research effort has gone into understand squat defects over the last 10 years which has brought about important developments in the understanding of their initiation mechanism; however, further work is still required to fully understand squat and the best methods to control them.This study considers records of squat defects over a period 9 years, considering 2600 km of track across 8 different routes on the GB mainline network. The analysis separately reviews squats on: plainline, crossings, joints and welds. Results include an overview of the main factors influencing the development of each type of squats, practical methods to immediately reduce and manage squat defects and recommends focus areas for further research to understand squat defects.Results suggest that squats on plainline, crossings, joints and welds, all correlate with different influencing factors; headcheck defects appear to significantly influence the probability of squats and how other factors influence squat development.There is a strong connection between total head wear rate (combined material removal due to traffic and grinding) and squats; 90 % of all squats appear on rail with a headwear rate of <0.2 mm/year. Overall larger section rail (60 kg/m vs 56 kg/m) and harder material (260 Brinell vs 220 Brinell) is significantly less susceptible to squat damage. Track curvature has an influence of squat development, especially in rail with no headcheck cracking, where the tightest curves are significantly more likely to sustain squat damage. The probability of squat at vertical discontinuities, i.e. joints and crossings are significantly more likely as train speed increases. Whilst squats on joints are 1000 time more likely than squats on welds.

Reductions in Energy Consumption and Emission of Harmful Exhaust Gases by Fishing Vessels

This article presents an analysis of the influence of engine types, fuel types and selected methods of fuel treatment before injection on reductions in fuel consumption and exhaust emission components. This is the first of such studies, the continuation of which will allow a comprehensive assessment of the impact of cutter operations on environmental pollution. For the selected type of cutter, EEOIs (Energy Efficiency Operational Indicators) were determined to be a measure that takes into account both fuel consumption and harmful gas compound emissions depending on the type of engine used and the type of fuel. The data necessary to prepare this analysis were obtained during operational tests carried out on selected cutters with various types of engines fuelled with liquid fuel and a new catalytic fuel treatment method developed by the authors, while for the case of using gas fuel and a common rail engine, possible effects were forecasted. The effects of engine type, years of manufacture and fuel type (liquid and gas) on fuel consumption and emissions of selected exhaust components are demonstrated. The positive effects on fuel consumption and emissions of harmful exhaust constituents obtained, under laboratory test conditions, for an engine fuelled with catalytically treated fuel have allowed further research directions to be set for cutter engines equipped with injection equipment with applied catalytic coatings.

Morphology and nanostructure of soot particles from diesel engine under transient and steady-state operating conditions with a microalgae fuel component, dioctyl phthalate biofuel

In order to adhere to strict emissions standards, it is necessary to reduce diesel particulate emissions under real driving conditions. This can be achieved by reducing the production of soot particles and optimising the combustion process within the combustion chamber. This investigation examines the impact of engine operating conditions (transient and steady-state) on the characterisation of the soot particles. Soot samples from a common rail direct injection (CRDI), turbocharged six-cylinder diesel engine without any aftertreatment devices were collected on TEM grids. This investigation utilised both pure diesel and diesel-dioctyl phthalate (DOP) blends (D90DOP10 and D80DOP20). To correlate the soot characterisation results, diesel particulate emissions were also measured using a fast particle analyser (DMS500). The results indicate that emissions from transient cycles are higher in comparison to steady-state engine operation. Smaller primary particle diameter with a compact structure were observed for transient cycles when compared to steady-state operating conditions. Parameters such as number of primary particles within a single aggregate, radius of gyration, and soot aggregate area were also studied. Nanostructure analysis reveals that the soot particles from transient cycles could have lower oxidation reactivity and longer fringes with less curvature and interplanar spacing.

Experimental study on effects of pilot injection mass strategy on combustion, Performance and emission characteristics of CRDI Engine

This experimental work reports how different pilot masses of biodiesel-blended fuel in Common Rail Direct Injection (CRDI) engines affect engine performance, combustion, and emissions. This experiment used 20MEWCO (20 % Methyl Esters of Waste Cooking Oil + 80 % Diesel) as the test fuel. Several parameters, such as timing and injection mass, affect how the CRDI system delivers fuel. In this work, the pilot injection mass was varied by 5 %, 7.5 %, and 10 %, keeping other factors such as injection pressure at 500 bar and the timing of the pilot and main injections at 36°Crank Angle before Top Dead Centre (bTDC) and 15°Crank Angle before Top Dead Centre (bTDC), respectively. This work reveals that when pilot mass is increased in steps of 2.5%, the combustion performance parameters like cylinder pressure, heat release rate and specific fuel consumption values decrease. Also, it gave off less smoke, carbon monoxide and hydrocarbons than regular diesel with more nitrous oxide. Also, it was found that at 10 % of the pilot mass, carbon monoxide, hydrocarbon, and smoke emissions were significantly reduced, with a slight rise in oxide of nitrogen emissions at the same time, without affecting the engine performance.

Experimental investigation of preheated ethyl ester of palm oil for a common rail direct injection diesel engine

The main aim of this research work is to study the performance and exhaust emissions of a common rail direst injection diesel engine at a constant speed of 1500 rpm under load variation by preheating fuels. Fuels are a neat ethyl ester of palm oil (EEPO) and its blended with diesel for the ratios of 10–50% v/v. The fuels are preheated to 65 ± 2 °C and 80 ± 5 °C, respectively. The results of preheated fuels compared with conventional diesel show the changes in performance parameters and exhaust emissions. The preheated neat EEPO resulted in the permutation of performance parameters. The brake thermal efficiency (BTE) reduced while the brake specific energy consumption (BSEC) increased, by 5%. Carbon dioxide (CO2) and nitric oxide (NO) were raised up to 18%, but carbon monoxide (CO) was dropped by 16%. Outstandingly, the preheated conventional diesel mixed with 10% EEPO improved the BTE and the BSEC by 2%. The preheating conventional diesel mixed with increasing EEPO (10–50% v/v) caused the increasing CO2 and NO but the CO emissions were continuously reduced.

Effect of Exhaust Gas Recirculation on a CRDI Engine fuelled with Biodiesel, Ethanol and Butanol

The global community has focused on the sustainability of petroleum-based fuel supply due to increased usage in various sectors, depletion of petroleum resources, and volatile crude oil market prices. We are looking for alternative fuel. As a result, we have chosen biodiesel. In this paper, a diesel blend containing biodiesel, ethanol, and butanol was created to test the characteristics of a common rail direct injection (CRDI) diesel engine equipped with an exhaust gas recirculation (EGR) system. The blends of diesel-biodiesel and diesel-biodiesel-ethanol-butanol were designated as B40 and B40-E10-BUT10 respectively. The experiment is carried out at a rate of 20% EGR. The experimental results show that the mechanical efficiency is higher in biodiesel blends than in diesel. The use of an EGR system with these blends reduces NOx by lowering the oxygen concentration in the combustion chamber.

CRDI Engine Emission Prediction Models with Injection Parameters Based on ANN and SVM to Improve the SOOT-NOx Trade-Off

Artificial Neural Network (ANN) and Support Vector Machine (SVM) have been widely used to solve non-linear problems. In the current study, based on 112 groups of experimental data, ANN and SVM models were established and compared to improve the trade-off relationship between SOOT and NOx emissions of a Common Rail Diesel Injection (CRDI) engine fueled with Fischer-Tropsch (F-T) diesel under different operating conditions and injection parameters. The model parameters for the different predictive targets were selected by evaluating the mean square error (MSE) and determination coefficient. Compared to the number of network iterations, the number of implied nodes had a greater effect on the MSE of the ANN model. Compared to the penalty parameter, the width coefficient had a weaker impact on the SVM performance. A comparative analysis showed that the SVM had better predictive accuracy and generalization ability than the ANN, with a maximum error not exceeding five percent and a determination coefficient of over 0.9. Subsequently, the optimal SVM model was combined with the NSGA-II algorithm to determine the optimal injection parameters for the CRDI engine, resulting in solutions to simultaneously decrease the SOOT and NOx emissions. The optimized injection parameters resulted in a 3.7–7.1% reduction in SOOT emission and a 1.2–2.6% reduction in NOx emissions compared to the original engine operating conditions. Based on limited experimental samples, SVM is inferred to be a useful tool for predicting the exhaust emissions of engines fueled with F-T diesel and can provide support for optimizing injection parameters.

Effect of diesel injection pressure for enhancing combustion and reducing mechanical vibration and noise emissions in a non-road diesel engine

In this study, the combustion, performance, emissions, noise, and vibration characteristics of a single-cylinder, four-stroke, air-cooled diesel engine used for non-road purposes were investigated by controlling different injection pressures with a common rail fuel injection system. The aim of this study is to enhance the combustion performance and improve the existing noise and vibration levels of this commonly used non-road diesel engine in fields such as agriculture, wetlands, and the construction sector by optimizing the injection pressure. The experiments were conducted under low and medium load conditions and at a constant engine speed. The single-cylinder, non-road engine's fuel injection system was controlled using a common rail fuel delivery system, and four different diesel injection pressures (250, 300, 350, and 400 bar) were utilized. The experimental results have shown that the combustion performance, emissions, noise, and vibration values of the non-road diesel engine improved with an increase in diesel injection pressure (DIP). Increasing DIP led to higher maximum combustion pressures and resulted in reductions of HC, CO, and smoke emissions by up to 25%, 48%, and 59%, respectively. Vibration values also decreased by up to 25%.

Investigation of the effect of advance angle on performance and emissions (exhaust, vibration, noise) in a single‐cylinder diesel engine whose fuel system is converted to common rail

AbstractIn diesel engines, the most important parameter affecting the combustion performance is the injection advance. Since the injection advance directly affects the combustion quality, it also directly affects the outputs, such as ignition delay, in‐cylinder pressure, fuel consumption, and emission values. Therefore, setting the advance angle correctly is exceedingly significant for the optimum operation of the engine in all conditions. In this study, a single‐cylinder diesel engine with a mechanical fuel system was converted to a common rail fuel system by revising its fuel system. Experiments were carried out with the converted engine at a constant speed (1850 rpm), at different loads (3–4.5–6–7.5–9 Nm), and at different advance angles (10, 12, 14, 16, 18°). In the experiments, engine performance and emission (exhaust, vibration, noise) data were examined. When the cylinder pressure data is evaluated, the maximum in‐cylinder pressure approaches the top dead point in parallel with the increase in the advance angle. Specific fuel consumption occurred at a minimum advance angle of 10° under all load conditions. In exhaust emissions, minimum values at 10° advance angle were obtained for all emissions except for oxygen emissions. Vibration emissions were reduced by 6% at a 10° advancing angle compared to 18° advancing angle at 3 Nm load. It was determined that noise emissions decreased by 1.76% in the same experimental parameters. When all data are evaluated, the optimum advance angle for the revised fuel system has been determined as 10°.

Evaluation of the influence of fuel pressure pulsation in the Common Rail system on the economic and environmental performance of a diesel engine

BACKGROUND: At present, all the worlds diesel engine manufacturers have directed their development strategy towards reducing harmful emissions, improving fuel efficiency and increasing power per liter. To achieve this, using only the Common Rail system is not sufficient. It is necessary to apply new additional devices, such as an exhaust gas converter, an exhaust gas recirculation system, the injection of additional fluids together with diesel fuel, as well as to improve existing ones. Increasing the accuracy of fuel delivery for an injector will make it possible to adjust the engine fuel system more precisely, leading to a positive effect on all areas of development of the diesel industry.&#x0D; In this article, the possibility of increasing fuel efficiency and reducing harmful emissions through exhaust gases of a diesel engine with a decrease in pressure pulsation in the accumulator of the Common Rail system is considered on the example of the D-442-59I-1 (4ChN 13/14) experimental four-cylinder diesel engine with a two-valve gas distribution system manufactured by Altai Motor Plant.&#x0D; AIMS: Study of the effect of fuel pressure pulsation in the Common Rail fuel system on the economic and environmental performance of a diesel engine.&#x0D; METHODS: On a non-motorized test rig, the dependence of the fuel delivery of the injector on the pressure in the accumulator was determined. To assess the effect of fuel pressure at the injector inlet on the performance of a diesel internal combustion engine, experimental designs of diesel engines were simulated using the specialized software. Theoretical studies have been carried out to assess the influence of fuel pressure in the fuel system.&#x0D; RESULTS: Data have been obtained on the effect of fuel pressure fluctuations in the high-pressure line on the injector cycling, harmful emissions and fuel efficiency.&#x0D; CONCLUSIONS: As a result of the study of the process of fuel supply and combustion in a 4CHN 13/14 diesel engine, it was found that with a pressure fluctuation range of 50 bar in the fuel accumulator, the concentration of wet NOx decreases by 11%. The concentration of solid particles increases to 13.4%, fuel efficiency deteriorates to 0.5% when the operating pressure of the fuel deviates 160 MPa in any direction from the set value.

Experimental study on the transient supply consistency for a common rail pump based on impedance theory

Common rail (CR) fuel pumps are characterized by pulsating supply, and instantaneous flow ripple is the main reason for the variation in supply consistency. To analyze the transient supply consistency of CR pump, a test bench for transient supply performance was originally designed and established. The potential effects exerted by pump speed and operating pressure on the pressure ripple were obtained under different fuel metering valve (FMV) openings. On this basis, an approach for the calculation of instantaneous flow ripple was proposed by combining impedance theory and hydraulic transmission line method (TLM). Furthermore, the coefficient of variation (CoV) of flow ripple amplitude was applied to evaluate the cycle-to-cycle consistency in fuel supply process. The results show that the rotational speed together with the plunger number determines the frequency of flow ripple. The pump presents a greater flow ripple amplitude under high speed and low pressure conditions, which further leads to an intense pressure ripple. Besides, in most operating points, the CoV is around 0.15, indicating a good transient supply consistency. When the FMV is partially open, under the coupled effect of FMV operating frequency and plunger movements, the value of CoV shows an oscillating trend as a function of speed.

Effect of different ammonia mixing methods for diesel ignition on combustion and emission performance of high pressure common rail engine

Ammonia is a zero-carbon fuel. Diesel/ammonia dual-fuel combustion mode can solve the problem of difficult compression ignition of pure ammonia. This article aims to explore the best mixing method and mixing ratio of ammonia fuel. The research results show that with the increase of the ammonia mixing ratio in the intake duct, the fuel consumption rate decreases by 7.71%. However, the serious ammonia escape phenomenon reaches a maximum of 37.35%, resulting in a serious decrease in power output. The cylinder temperature dropped by 197.12K, CO2 emissions decreased by 49.34%, NOx emissions decreased by 16.84%, and emissions significantly improved. When using direct injection ammonia mixing in the cylinder, as the ammonia mixing ratio increases, the explosion pressure in the cylinder decreases by 8.32%, the temperature in the cylinder decreases by 127.37K, the maximum ammonia escape is only 6.89%, CO2 emissions decreased by 88.10%, NOx emissions decrease by 75.90%, and CO2 and NOx emissions significantly decrease. Compared with the two ammonia blending methods, the direct injection ammonia blending method in the cylinder is obviously better. When the direct injection ammonia blending ratio in the cylinder is 70%, compared to the original engine, the diesel engine has the best working performance, increased power, and improved economy by 7.52%, and the proportion of ammonia escape is small. CO2 emissions are reduced by 69.05%, and NOx emissions are reduced by 29.22%. The research results of this article provide data support for achieving energy-saving, emission reduction, and low-carbon environmental protection of diesel engines.

Implementation of a Non-Surfactant Water-in-Diesel Emulsion Fuel in a Common Rail Direct Injection Diesel Vehicle

Implementation of a Non-Surfactant Water-in-Diesel Emulsion Fuel in a Common Rail Direct Injection Diesel Vehicle

Engine vibration and noise characteristics of common rail direct injection engine fuelled with orange peel oil by response surface methodology based multi-objective optimization

The present study aims to find out the noise and vibration & compatibility of OPO (orange peel oil) in the common rail direct injection engine. Various injection strategies like FIP (fuel injection pressure), pilot mass, pilot injection timing, and engine speed are examined at idling mode using the design of experiments software. The obtained results are post-processed and computed in the form of perturbation and surface plots based on RSM (response surface methodology) and analysis of variance. Considering the trade-off with combustion parameters, the engine speed is found to be more responsible for crank level vibrations while FIP created more influence in head level vibrations. OPO B20 (20% OPO + 80% diesel by volume) injected 28° CA bTDC (before top dead centre) is predicted to be optimum by using RSM. In the case of diesel fuel, vibrations at the head level show a noticeable increase in all three directions as the FIP is raised. However, when using a OPO B20, the vibrations primarily in the z-direction are significantly affected by the FIP changes. Additionally, for OPO B20 fuel at idling operation, the pilot mass of 20%, engine speed at 979 rpm, and a fuel injection pressure of 300 bar are the optimal setting condition to achieve favourable characteristics of combustion, vibration and noise.

Influence of Ethanol Blended Diesel Enriched with Hydroxy Gas in Dual-Fuel Mode on Common Rail Direct Injection Engine

This study investigated the impact of dual-fuel operation using ethanol-blended diesel fuel enriched with hydroxy gas on CRDI engine performance, combustion, and emission characteristics. Neat diesel fuel was used to run the engine, along with a 20% volume fraction of an ethanol-diesel mixture that had been enhanced with three distinct streams of hydroxy gas, namely 1, 1.5, and 2 LPM. Hydroxy gas was generated by an electrolysis technique using a plate-type dry cell electrolyser (316 L stainless steel) in the presence of a NaOH catalyst. Compared to E20 (Ethanol 20%) fuel, HHO gas enrichment with lower proportions of ethanol blend E20 + 2LPM had a 2.74% increase of BTE and a 5.89% decrease of BSEC at a 5.02 bar BMEP condition. Similarly, HC, CO, and smoke emissions decreased by 4.61%, 5.19%, and 3.1%, while NOx emissions and EGT increased by 3.22% and 3.06% compared to E20. With the addition of HHO gas, combustion characteristics such as HRR, CP, and ignition delay improve while the combustion duration increases. At maximum BMEP, cylinder pressure and heat release rate increase by 3.18% and 6.58% for E20 + 2LPM HHO, respectively. It was found that the 20% volume of the ethanol-diesel blend, with 2 LPM of hydroxy gas, positively affects engine characteristics.

Study of the Optimization of Rail Pressure Characteristics in the High-Pressure Common Rail Injection System for Diesel Engines Based on the Response Surface Methodology

This paper establishes a mathematical model of the high-pressure common rail injection system used in diesel engines according to the parameters of its key components, and AMESim 2020 software was used to establish a simulation model of the common rail injection system used in diesel engines. The simulation model mainly includes a high-pressure oil pump model, a common rail pipe model, and a model of four injectors. This paper also describes an experimental analysis of the accuracy of the established simulation model. Through a simulation analysis of the system rail’s pressure fluctuation and pressure characteristics, it was concluded that the length of the common rail pipe, the diameter of the common rail pipe, and the inner diameter of the high-pressure fuel pipes are important influencing parameters for the rail pressure characteristics of the system. In this study, according to the original common rail pipe and high-pressure fuel pipe model, a response surface methodology was used to optimize and analyze the parameters of the common rail pipe and high-pressure fuel pipes, and the optimal size parameters for the common rail pipe and high-pressure fuel pipes were obtained with the minimum rail pressure fluctuations and the average rail pressure setpoint. After the optimization, the pressure for the common rail pipe of the high-pressure common rail system was increased by 0.82%, the pressure fluctuation was reduced by 21.66%, the injection pressure was increased by 1.15%, the single injection volume was increased by 0.86%, and its fuel injection characteristics were significantly improved.

Compound control of rail pressure in dual common rail injection system based on a dual regulating valve

To improve the performance of fuel injection in high power diesel engines, high pressure dual common rail system (HPDCRS) is made to match high power diesel engine, proportional-integral-derivative (PID) compound control for rail pressure is proposed based on dual regulating valve: pressure balance valve (PBV) and pressure control valve (PCV), a PID hybrid neural network (PID-HNN) is provided to complete tuning and match of PID coefficient automatically, simulation control modelling of rail pressure is made by MATLAB software, pressure control comparison of dual common rail is made with PID compound control method. The pressure control effects illustrated that PID compound control of dual regulating valves can rapidly trace different target pressure and reduce rails pressure wavelet, and feasibility of compound control is verified in dual common rail pressure.

Experimental study on radial diffusion characteristics of diesel–pentanol spray

It is always a hot topic to find alternative fuel for diesel. Pentanol is a potential alternative fuel for diesel. In this study, different volume ratios of fuel were obtained by adding pentanol to diesel. On the high-pressure common rail experimental platform, the spray processes of pure diesel and diesel–pentanol blends were observed and analyzed, and the differences of radial diffusion capability between different experimental fuel sprays were evaluated. The maximum radial diffusibility was analyzed through the maximum width and the maximum width corresponding to the axial position. The radial diffusion capacity of the whole was analyzed by means of the average width and spray cone angle, and the area of the gas entrainment area was analyzed. The results showed that the addition of pentanol enhanced the radial diffusion ability and gas entrainment ability of diesel sprays.

Development and analysis of the loading characteristic of accumulate fuel injection system Common Rail of the engine 50 RT-flex

The object of research are hydrodynamical processes in fuel delivery system of marine diesel engine of type RT-flex with accumulate fuel injection system of type Common Rail. The problem, being solved, is maintenance of an effective operation of the specified diesel engines due to perfection work of their fuel equipment. The results of simulation modeling of the injection process by accumulator fuel delivery system Common Rail of the 50RT-flex engine are presented. On the basis of the functional diagram of system, a calculation model has been compiled that provides a description of the operation of the systems main blocks. The load characteristic of the fuel equipment is built in the traditional version – the dependence of the fuel delivery parameters from the engine load at a constant speed. For the system under consideration, the control element is the valve assembly connecting the injection control unit (ICU) with injectors. The parameters of the load characteristic in this study are modes with a constant engine speed n=124 rpm and a change in the opening angle of the control valve in the range – jv=6.6–14.4 °CA. The parameters of the devices that largely determine the characteristics of the fuel delivery and the quality of the working processes of a diesel engine are considered in more details. Such an element of the system is ICU, the working body of which is the dosing piston. The main parameters of its operation when delivering fuel are the magnitude and speed of the stroke. For the load characteristics in the accepted range of the valve control valve opening angle jv from 6.6 to 14.4 °CA (2.18 times), the piston stroke was hp=4.29–8.61 mm (2.0 more). In this case, the dependence of hp on jv is linear. Area of use of the data received during research, ship crews and the shore services providing operation of vessels are. A material is applied in process of high school and is already used in various educational forms. The given researches are useful to developers and builders of marine diesel engines of a considered class.