Diesel Engine Design Research Articles

Effect of grooved cylinder liner depths on the tribological performances of cylinder liner-piston ring

PurposeFrictions in cylinder liner-piston ring often cause an inevitable loss of energy loss in the diesel engine. This study aims at evaluating the effect of depths in the cylinder liner groove texture on friction, wear and sealing performances.Design/methodology/approachFive depths of groove texture cylinder liners (50, 100, 150, 200, 250 µm) were fabricated, and experiments were carried out using a special-purpose diesel engine tester. Comparative analyses of cylinder liner contact resistances, piston ring wear losses and surface appearances were conducted with respect to different surface textures and applied loads.FindingsUnder no-load conditions, the cylinder liner with a 100 deep thread groove can significantly improve sealing and optimize its lubrication performance. On the other hand, the sealing is highly correlated with the depth of groove and the load within the cylinder liner. Under loaded conditions, the thread groove has less effect on the sealing performance.Originality/valueThe findings can provide feasible basis for the tribological design and production of diesel engines.

Thermal performance and mechanisms of soot deposition in foam structured exhaust gas recirculation coolers

Exhaust Gas Recirculation (EGR) coolers are commonly used in diesel engines to reduce NOx emissions. New diesel engine designs though require compact EGR coolers that can withstand severe deposition. This study aimed at determining the underlying mechanisms of soot deposition in metal foam structured EGR coolers. Various experiments were performed for 20 PPI aluminium foam at inlet gas temperatures of 250 and 400 °C and coolant temperatures of 25 and 90 °C to discern the importance of thermophoresis. The experimental results revealed that the thermophoresis would not be of great concern in the investigated metal foam as otherwise would have been expected in conventional flat EGR coolers. This has been attributed to the thermal equilibrium between fibers and the flue gas which was confirmed by visualization of fouled foams after experiments. In the absence of thermophoresis, isothermal soot deposition on the fibers, including interception, diffusion and inertial impaction were also investigated. For this purpose, a model is proposed to compare deposition velocities due to the aforementioned mechanisms. It is shown that interceptional deposition velocity was marginal, while inertial impaction was important for soot deposition on fibers, especially at higher inlet gas velocities and larger foam PPIs. Diffusion also made a contribution of about half of the total soot deposition on the foam ligaments at a gas velocity of 10 m/s. Finally, a comparison between foam structured and current EGR coolers showed that the higher pressure drop penalty of using foam as EGR cooler can be compensated by partial filling of the channel.

Optimization of a DI diesel engine to reduce emission and boost power by exergy and NLPQL method

AbstractThe design and manufacture of efficient diesel engines, which can convert the majority of fuel combustion into a mechanical rotation movement is still growing. Simultaneous investigation of optimum engine configuration and the second law of thermodynamics consideration can best achieve this goal. A baseline 1.8 Ford diesel engine is simulated via AVL Fire software and then the multiobjective nonlinear programming by quadratic Lagrangian method have been applied to find the global optimal design. Then for exergy analysis of the baseline and optimized engine characteristics, a FORTRAN developed code is used. Two basic optimization cases are detected for exergy assessment that are RunID41 (feasible design) and RunID35 (infeasible design) among 55 run points. It was determined that the optimum feasible solution should characterize with low inner wall diameter (Di) with wider half spray cone angle to avoid wall collision in order to stay in the constraint zone and feasible area. The results of exergy also indicates that RunID41 is fuel efficient since the fuel burnt exergy of three design of ID41, ID35, and baseline are 719.52, 694.77, and 643.07 J, respectively. It has also been pointed out that the feasible optimum gives the higher thermo‐mechanical exergy, work exergy, and total exergy, while the infeasible optimum yields a higher heat release rate exergy and chemical exergy as there are no restrictions of injection and combustion chamber geometry set by the designer.

Smoothed Finite Element Methods for Predicting the Mid to High Frequency Acoustic Response in the Cylinder-Head Chamber of a Diesel Engine

Modeling and simulation of the acoustic response in enclosed cavities of a diesel engine are of great significance for optimal design of an engine to achieve a better acoustic performance. Nevertheless, the use of the traditional finite element method (FEM) for the mid to high frequency acoustic prediction is limited by the well-known numerical dispersion errors and the tedious preprocessing of the model. Smoothed finite element methods (SFEMs) proposed originally for solid mechanics have been employed for the modeling of acoustic problems in the low to medium frequency ranges whilst acoustic modeling in the mid to high frequency range remains untouched. This paper comprehensively investigates into the performance of SFEMs in modeling and simulation of mid to high frequency acoustic problems. It is shown that the mass-redistributed edge-based smoothed finite element method (MR-ES-FEM) can yield an excellent prediction result in the mid to high frequency range in terms of accuracy, efficiency and robustness. The MR-ES-FEM is also used to simulate sound propagation in a cylinder head chamber of a four-cylinder diesel engine to prove its effectiveness. The findings presented in this paper offer an in-depth insight for engineers to select suitable numerical methods for solving mid to high frequency acoustic problems in the design of diesel engines.

Performance Analysis of Diesel Cycle under Efficient Power Density Condition with Variable Specific Heat of Working Fluid

Abstract A novel realistic Work Criteria Function (WCF) approach has been used to analyze the ideal air-standard Diesel cycle. The WCF formulation gives rise to a new performance criterion which is termed as efficient power density (EPD). Thermodynamic analysis under maximum efficient power density (MEPD) conditions has been performed and compared with other available performance criteria using variable specific heats of the working fluid. The results obtained from this analysis prove that the engine designed under MEPD conditions is very efficient and the size of the engine is reduced significantly compared to those designed under maximum efficient power (MEP), maximum power density (MPD), and maximum power (MP) criteria. Harmful emissions like NO x {\mathrm{NO}_{\mathrm{x}}} may decrease considerably at higher values of the maximum cycle temperature ratio (ξ). The effect of variable specific heats of operational fluid on the actual cycle’s performance has a significant impact on engine performance and should be incorporated when evaluating practical cycle engines. The results obtained in the current study have scientific importance and could be an essential guide for the design of real Diesel engines by engine manufacturers.

Thermodynamic Analysis and Optimization of an Irreversible Maisotsenko-Diesel Cycle

So far, Maisotsenko cycle has been applied to many fields such as heating ventilation and air-conditioning, power industry, chemical production, and so on. A lot of researches about classical thermodynamic analyses of Maisotsenko cycle have been made. A new cycle model of combined Diesel and Maisotsenko cycles considering heat transfer loss (HTL), piston friction loss (PFL) and internal irreversible loss (IIL) was proposed in this paper. By using the finite time thermodynamic (FTT) theory, the power and efficiency performances of the Maisotsenko-Diesel cycle (MDC) were studied. Effects of mass flow rate (MFR) of water injection in the Maisotsenko air saturator (MAS) and the other parameters related to the design of Diesel engine on the optimal cycle performances were analyzed. Furthermore, it was testified that irreversible MDC was superior than conventional irreversible Diesel cycle in both power output and thermal efficiency. The results can expand the application of Maisotsenko cycle (M-cycle) and provide some theoretical guidelines for the practical devices.

Engine Modelling of a Single Cylinder Diesel Engine Fuelled by Diesel-Methanol Blend

Performance on diesel engines with various combustion chamber sizes and fuel injection require effective handling so that the root combustion process in large diesel engines is timely. This study compares the experimental data with simulation through the single cylinder diesel modelling using GT-Power software. This simulation utilises parameters in diesel engines of 1000 and 2000 rpm speeds with methanol and diesel fuels. This modelling aims to develop a single cylinder diesel engine by measuring all components on the machine. The comparison between the simulation results and experimental data indicate similar collaboration with a difference about 5%–10%. Based on the results, the modelling of developed machine shows that simulation using GT-Power software is able to successfully validate all machine data parameters up to 90%. This simulation result can be expressed accurately similar to the experimental results and can be used as standardization for a single cylinder diesel engine design.

High pressure densities and derived properties of biodiesel fuel produced by heterogeneous transesterification from biowaste

High pressure density of biodiesel is a crucial parameter necessary for the Diesel engine design and performance improvement as well as proper combustion optimization. Biodiesel production utilizing biowaste as raw material reduces the capital costs and environmental problems related to biowaste disposal. In this investigation, biodiesel was synthesized in a heterogeneous transesterification reaction utilizing used cooking oil and methanol as reactants and eggshell raw material as a calcium-oxide catalyst source. Calcination was carried out at temperature 1073.15 K for 4 hours and transesterification was conducted at 338.15 K. Densities of produced biodiesel were measured at pressures up to 60 MPa and over the temperature range 288.15-413.15 K and fitted employing the modified Tammann-Tait equation. Viscosities of biodiesel are also measured at atmospheric pressure over the temperature range 288.15-338.15 K. From measured density data, important mechanical properties, such as the isothermal compressibility and the isobaric thermal expansivity, were calculated. High transesterification reaction yield was obtained (almost 99 wt.%) while densities and viscosities of analyzed biodiesel sample were in accordance with recommended standard values.

Operational profiles of ships in Norwegian waters: An activity-based approach to assess the benefits of hybrid and electric propulsion

Various regulations are imposed on shipping to increase energy efficiency and reduce environmental impacts. Alternative fuels and power systems are among the solutions for compliance with these regulations. The power system of a ship may not operate optimally because of the diversity of the operational profile during its lifetime. This article uses an activity-based approach and big data from the Automatic Identification System (AIS) to study the operational profiles of eight ship types operating in Norwegian waters around mainland Norway in 2016. The aim is to identify ship types that can benefit from electric and hybrid propulsion through analysis of their operational profiles. Close to shore, the operational profiles of various ship types are similar, and all ships spend a great proportion of their time with lower loads. As the distance from shore increases, the operational profiles of various ship types follow distinct trends. Among the considered ship types, reefers spend more operational time close to the diesel engine design condition. On the other hand, offshore and passenger ships show the most dynamic operational profiles and spend a large percentage of their operational time with a partial load, away from diesel engine design conditions. Such ships can benefit from hybridisation, diesel-electric propulsion, and other electric concepts, such as batteries and fuel cells. Another option is to downsize diesel engines for better operation while fuel cells and batteries supply peak and partial loads. Operational profiles are plotted and details of the approach are presented in the article.

Mathematical model of turbocharger as part of intelligent system component designed for technical operation of diesel engines and for training

The paper includes a basic module of a slow speed ship diesel engine turbocharger. Our experience in modelling and simulation makes it possible to produce flexible models. Next, a control system needs to have operational modules in real time, with sufficient range of precision. This is a light algorithm under Delphi area. Module makes up a part of smart intelligent pack. Pack is a software that combines and solves the task of exploitation and design of modern slow speed diesel engines. The module allows to construct the working mode line and to examine the behaviour of the operating point quasi-statically. The model is based on a quasi-static approach for real-time operation in a software package including a flexible input simulator and modules for solving constructive and operational tasks with graphical retrofit based on image recognition

Selection of accelerated test modes for the head of cylinder of the automobile diesel engine

The possibilities of a prediction of the heads of cylinder durability of the automotive diesel engines at the design stage and their completion to specified parameters, especially for reliability are considered. Since diesel engines operate in the unsteady modes, the main load is not only mechanical, but also thermal. At that, it occurs when the operating modes of the diesel engine change. The most loaded sections in the cylinder head are the bridges between the inlet and exhaust valves, as well as the bridges between the nozzle holes and inlet and exhaust valves. Under the influence of the thermal load, the distortions of the crystal lattice appear in the sections of the cylinder head at first, which leads to the appearance in some direction in which the greatest tangential stresses act, tears, gradually change under the influence of alternating stresses in the crack. When the total accumulated damage reaches a certain critical value, and the crack substantially weakens the cross section, fatigue failure occurs. To ensure the reliability of the diesel engine in operation, it is necessary to choose such methods of calculation and testing that would ensure a specified durability of the cylinder head. Since the reliability check in operation takes considerable time, that accelerated testing is used to reduce the test time. The place occupied by the accelerated tests in the design of diesel engines, as well as the sequence of the formation of their program are considered. It is shown that in practice it is possible to achieve only a certain degree of change in the technical condition of the cylinder head due to the degree of completeness of the accounting of the interacting operational loads and their distortion during reproduced on the test equipment. Possible modes of testing the cylinder heads on a non-motorized thermal bench are proposed with the aim of a determination their durability. They correspond to the modes of accelerated tests for the reliability of the automobile diesel engines. The problem of convergence of the results at accelerated tests and the data under operating conditions is considered.

Design of high duty diesel engine connecting rod based on finite element analysis

Connecting rod of an internal combustion engine is subjected to complex loading conditions. These mainly include the forces created through combustion in the combustion chamber of cylinder causing compression and bending of the connecting rod. This paper reports the results of a project objected to design the connecting rod of a heavy duty marine diesel engine and to modify its structural details based on finite element analysis. For this purpose, the initial design of the connecting rod was conducted by CATIA software and imported as stp file in Abaqus software. Results of the FEM model were utilized to modify the CAD model based on critical stress spots and magnitude of deformations of different sections of analyzed connecting rod model. Also, these results were used to introduce appropriate materials to tolerate the magnitude of forces developed under maximum combustion pressure of 190 bar. Further FEM analyses were carried out to modify the design in order to reduce the weight of final model of connecting rod. Results of finite element analysis of the final model revealed that the levels of stresses of the designed connecting rod are reduced significantly below the yield stresses of suggested materials for production of the connecting rod.

Performance investigation of a Diesel engine under effective efficiency-power-power density conditions

A performance analysis of a Diesel engine in terms of effective power (EP), effective power density (EPD) and effective efficiency (EE) has been performed using a novel realistic finite-time thermodynamics (FTT) modeling. The effects of design and operating parameters of the diesel cycle such as bore-stroke length ratio (d/L), equivalence ratio (ER), compression ratio (CR), cycle temperature ratio (CTR), cycle pressure ratio (CPR), stroke length (L), friction coefficient (FRC), engine speed (N), mean piston speed, inlet pressure and inlet temperature on the engine performance have been investigated. In addition, the energy losses depending on incomplete combustion (IC) , friction losses (FRL), heat transfer losses (HTRL) and exhaust output losses (EOL) have been described as fuel input energy. In order to acquire reasonable results, variable specific heats with respect to temperature for working fluid have been used. The results presented could be an essential tool for Diesel engine designers.

Research performance of novel design of diesel engine

Research performance of novel design of diesel engine

Analysis of BJ493 diesel engine lubrication system properties

The BJ493ZLQ4A diesel engine design is based on the primary model of BJ493ZLQ3, of which exhaust level is upgraded to the National GB5 standard due to the improved design of combustion and injection systems. Given the above changes in the diesel lubrication system, its improved properties are analyzed in this paper. According to the structures, technical parameters and indices of the lubrication system, the lubrication system model of BJ493ZLQ4A diesel engine was constructed using the Flowmaster flow simulation software. The properties of the diesel engine lubrication system, such as the oil flow rate and pressure at different rotational speeds were analyzed for the schemes involving large- and small-scale oil filters. The calculated values of the main oil channel pressure are in good agreement with the experimental results, which verifies the proposed model feasibility. The calculation results show that the main oil channel pressure and maximum oil flow rate values for the large-scale oil filter scheme satisfy the design requirements, while the small-scale scheme yields too low main oil channel’s pressure and too high. Therefore, application of small-scale oil filters is hazardous, and the large-scale scheme is recommended.

Research on visual 3D assembly process design and simulation for marine diesel engine

In view of the backward traditional assembly process design model in shipbuilding industry, the research on the visual assembly process design and simulation of the marine diesel engine is an innovation for the marine diesel engine manufacturing model. This paper studied the key technologies such as structural assembly process design and assembly process simulation. In addition, following the principle of unified data source, through independent development and application on the platforms of Teamcenter and Vis MockUp, this research removed the obstacles in the integration of visual 3D assembly process design and simulation, took the lead in transforming the whole marine diesel engine assembly model from 2 dimensions to 3 dimensions, and made the methods of process verification and assessment more advanced. Finally, taking key parts of certain marine diesel engine as an example, this research verified the feasibility of the assembly process design system, and improved the stability and reliability of the marine diesel engine assembly process design.

A Novel Fuzzy Methodology for Quality Function Deployment Based on TOPSIS

Quality function deployment (QFD) is widely accepted as a product-designing tool. QFD could turn customer quality requirements into the engineering measures of a product. Ranking the importance of engineering measures according to the input data is a critical procedure in this fuzzy methodology. When the relative weights of quality requirements of customer and the relationship measures between quality requirements and engineering measures are evaluated by Interval-valued intuitionistic fuzzy sets (IVIFS), calculating the importance of each engineering measure depends on the operations between IVIFSs. With the target of prioritizing engineering measures in this fuzzy methodology, this paper presents a novel method by integrating the new aggregation operators based on the Łukasiewicz triangular norm, which is monotone with respect to the total order of IVIFS, and the TOPSISbased nonlinear-programming methodology. In addition, an application example of diesel engine design is provided to test the practicality and extensibility of the novel fuzzy methodology.

Motion and Stress Analysis of Cam System for Marine Diesel Engine 93 KW

The developments of maritime sector in Indonesia shows increasing demand for ships. Especially ships with size of 30 GT has problem with low availability of the ship engine, which most of the ships still use non marine diesel engine as its main propulsion. The problem gives interest to make a step to improve by design marine diesel engine using reverse engineering method. Cam system of marine diesel engine design was needed to be calculate to select the material and the motion. The design of cam system needs study about the stress analysis in cam system to make sure the distribution of force and moment. The result of stress analysis was used to select material of components in cam system. The motion analysis result was used to be input data of stress analysis. The condition to obtain the stress of components was on maximum condition, its contain pressure, torque, rotation, and force. All component that calculated are camshaft, lifter (flat-tappet), push rod, rocker arm, spring, and valve. Each component was given two different materials and material selection was based on safety factor of each component. Material for camshaft and lifter were malleable cast iron, for push rod and rocker arm were mild steel, for spring was ASTM A231, for intake valve was steel JIS SUH3, and for exhaust valve was steel JIS SUH35. The result of motion analysis were angular velocity of camshaft with value was 2400 deg/sec, friction force between camshaft and lifter with maximum value was 125.393 N, and contact force between camshaft and lifter with maximum value was 845.307 N, and linear velocity of intake valve with maximum value was 696.573 mm/s, and linear velocity of exhaust valve was 463.734 mm/s.

Design and Performance Optimization of Off-highway Diesel Engine with Mechanical Fuel Injection Equipment for TIER-IV Emission Norms

The two cylinder diesel engines are most demanding product in Indian market for power genset and tractor applications. But major task faced by engine manufacturers all over the world is to upgrade running engine designs with minimum and cost-effective modifications to meet the next level of emission norms. This saves the precious lead time and investments. In addition uncomplicated design has to be sustained as far as possible while improving emissions. Further the basic desires of the end user in off-road market are good response, transient performance, better low end torque, best fuel efficiency and smooth operation of the engine besides best in class reliability. Additional requirements needed to sustain the market with higher power to weight ratio and increased life of the engine. Henceforth turbocharging applications for off-road diesel engines are promising solution for enhancing rated power, low speed torque, transient performance, optimized fuel efficiency and engine downsizing. A trade-off is required to match some incompatible design issues like overall dimensions, cost, emissions control and performance in order to sustain the existing design. Future diesel engine emission standards will restrict vehicle emissions, particularly nitrogen oxides. In the present work, performance improvement for 1.7L, 2 cylinder in-line naturally aspirated diesel engine with mechanical fuel injection pump for off-road application is developed to contain all needs of the market. Design up-gradation of this engine for Tier IV is made with minimal design changes by optimal combinations of fuel injection equipment. This includes proper optimization of performance with improvements in nozzle geometry, change in injector end pressure. But due to the increased fuel flow rates for improving the engine performance as well as emission reduction, there is also a requirement for increased air flow. Henceforth in this study air flow rate is simulated and discussed for selection of turbocharger and intercooler. Further elaborate design and analysis study is also done on cooled exhaust gas recirculation system for exhaust gas cooling efficiency, Diesel Oxidation catalyst, Selective Catalytic Reduction /Lean NOx Trap substrate selection for reduced pressure drop and maximum retention time for exhaust gas to achieve Tier IV norms in turbocharged intercooled two cylinder engine.

Experimental Investigations of the Effects of Electric Control Impulse on Injection Characteristics of Common Rail Type Injector

Background/Objectives: The motor-less fuel stand has been described capturing high-speed video in the process of fuel jet development in Common Rail type injector. Methods: The experiments were carried out simultaneously recording the electric signals of the start and end moments of the electrical impulse controlling the injector with digital color oscilloscope Tektronix TDS-2014С and high-speed imaging of the fuel jet sprays with color video camera FASTCAM SA-X2. Findings: The delays of the start and termination of actual fuel injection that depend on the electrical impulse for the injector control have been determined and the dynamics of the fuel jet development has been observed under the fuel rail pressure from 100 to 165 MPa. The dependency of the duration of the fuel injection process on the duration of the electrical impulse controlling the injector has been established. Applications/Improvements: The results of the study can be used for diesel engine design and commissioning and for improving the shape of the combustion chamber to ensure better carburetion in the cylinder.