Combustion Engine Piston Research Articles

Numerical simulation and experimental analysis of acoustic wave influences on brake mean effective pressure in thrust-ejector inlet pipe of combustion engine

This paper is focused on a numerical simulation and experimental analysis of acoustic wave influences on brake mean effective pressure in a thrust–ejector inlet pipe of a piston combustion engine. The experiment is based on a real racing motorbike, which is driven by a piston combustion engine, equipped with a newly developed and patented thrust–ejector inlet pipe. This new inlet pipe is able to eliminate problems concerning an insufficient charging of cylinder with a fresh mixture. The engine sucks the air by overpressure, which is directly related to increased performance and torque. The first part of this paper presents the analytical relations describing acoustic waves in an inlet pipe. The next part contains a numerical simulation performed by software Ansys CFX in order to obtain a detailed description of flowing air, which passes through the ejector into the air box. The experimental measurements were realised using the data–recording system EW&C.

PRELIMINARY TESTS ON A COMBINED HEAT AND POWER UNIT FED WITH GAS FUELS

This paper presents a model unit demonstrating the possibility of using a PBCHP10VB CHP unit driven by a piston combustion engine fed with gas fuels for heat and power cogeneration. A mobile unit available in the Department enables heat and power cogeneration at any place with available gas fuel, e.g. compressed in a pressure tank or from a production and transmission system. A radiator is connected to the unit’s heat connection for demonstrative purposes – this is the simplest model of a network using the heat generated by the unit, with the possibility of easy connection to another network for heating rooms and/or tap water instead of this radiator. Any three-phase load (e.g. a single phase converter) can be connected to the unit’s power connection. A constructed mobile power generator fed with alternative gas fuels (e.g. biogas) is described which can be used in the field in a biogas system for power generation with simultaneous heat recovery. The results of the first preliminary tests on the effect of the type of gas fuel used on the obtained electrical and thermal power and on the composition of exhaust gas from the driving combustion engine are presented. A plan for further tests is also outlined.

TEST STAND FOR A COMBINED HEAT AND POWER UNIT FED WITH ALTERNATIVE GAS FUELS

This paper presents the reasons for the development of gas-combined power and heat units and justification for testing the effect of the used gas fuel on the performance of such units. A PBCHP10VB CHP unit driven by a liquidcooled piston combustion engine adapted for feeding with gas fuels is described. The concept is presented for testing the effect of different gas fuel mixtures, including biogas, on this unit’s operation, mainly on the obtained electric power from the current generator and the temperature of the liquid cooling the driving engine heating up output water and on the composition of exhaust gas from this engine. A simple device for obtaining gas fuels containing different combustible gas mixtures is presented. The instruments used to check the composition of the obtained gas fuel and check exhaust gas from the engine are briefly described. The paper describes a test stand for testing the effect of different gas fuels on the operation of a PBCHP10VB gas CHP unit manufactured by Power Blessed Co., Ltd registered in Shanghai, constructed at the Department of Mechatronics and Technical and Information Technology Education of the Faculty of Technical Sciences at the University of Warmia and Mazury in Olsztyn.

RESEARCH OF WATER-FUEL MICROEMULSIONS AS FUEL FOR DIESEL ENGINE

The combustion of fuels is and will be in the nearest future a basic way of acquiring the energy, among others, for transport purposes. Transport causes many threats for natural environment. It produces powders and particulates, together with many gaseous noxious substances and is also the source of noise and vibrations. Sources of propulsion, applied in transport, are almost exclusively piston-combustion engines, among which the dominant role play self-ignition engines. In the light of well-known advantages of these engines, they were accepted as most beneficial sources of car vehicles’ propulsion in nearest decades, provided they meet the requirements of the future legal regulations regarding the environmental protection. The emission of nitrogen oxides (NOx) and particulate matters (PM) is a problem to be solved in modern engines. This constitutes so called targets conflict, consisting in excluding the alternative of both coefficients’ decrease, in the way of regulation the set of an engine and the limiting emissions, permitted by the EURO regulations. From among many different methods of limiting both the formation and emission of NOx, the method of the selective catalytic reduction (SCR) is universally applied. This method requires special installation with the catalyst and the reservoir intended for the „clinically” clean reductive measure. In the aspect of constituting opinions regarding the need of reducing additional installations and media on board the vehicle, it seems that to supply the engine with fuel-water emulsion and especially fuel-water microemulsion becomes an interesting solution.

CAD/CAM/CAI Application for High - Precision Machining of Internal Combustion Engine Pistons

CAD/CAM/CAI Application for High - Precision Machining of Internal Combustion Engine Pistons

Ultrasound for the non-invasive measurement of internal combustion engine piston ring oil films

Increasingly stringent legislation controlling vehicular emissions is motivating research to maximise engine efficiency. The frictional power loss associated with the ring pack–cylinder interface is one such focus. In addition to this, increased reliance on simulation to predict the lubrication characteristics requires that numerical codes model the physical situation accurately and reliably. Experimental validation provides the crucial role of assessing performance and lubricant film thickness provides a key comparable parameter. This paper outlines oil film thickness results obtained from the compression ring–cylinder interface of a fired, single-cylinder gasoline engine using a method based on ultrasonic reflection. The magnitudes of the film are discussed and compared with work published by other experimental investigators using alternative techniques.

Laboratory Experiments on Oil-Jet Cooling of Internal Combustion Engine Pistons: Area-Average Correlation of Oil-Jet Impingement Heat Transfer

AbstractOil-jet cooling of internal combustion engine pistons has risen in prominence with the need to improve fuel economy by increasing the power density of engines. Laboratory tests were performed on a production automotive piston under a range of conditions representative of engine conditions to develop a suitable area-average heat transfer correlation to be employed for numerical evaluation of oil-jet cooling of internal combustion engine pistons. In addition to the Reynolds and Prandtl numbers, the Nusselt number was found to be a function of the dimensionless nozzle diameter and viscosity, and a weak function of the dimensionless nozzle-to-wall spacing.

Actuation of Control System for Racing Engine Using Active Data Maps

The modern systems developed for a control of ignition and fuel injection in the racing piston combustion engines require a continuous supplementation of the input information, together with permanent monitoring and correction of these input data. Such operations are performed by means of specialized software, which is able to decode the maps of active data fields as well as to modify them afterwards in the framework of the required values. The correct editing of the data field enables a faster and more accurate distribution of the active values.

Experimental Studies of Mechanical and Microstructure Properties of Plasma Sprayed Thermal Barrier Coatings

This research work mainly deals with the mechanical and microstructure properties of various thermal barrier coating (TBC) materials for an internal combustion engine piston using plasma spraying technique. Three thermal barrier coating Materials namely the combination of Aluminium Oxide with Titanium oxide (87%Al2O3 + 13%Tio2), Aluminium Oxide with Titanium oxide (97% Al2O3 +3%Tio2) and Yttria Stabilized Zirconia (YSZ) (100%) were selected and coated on Aluminium Alloy(Al Ai) with the thickness of 150 Microns (µm) for this investigation. Among three Thermal barrier coating materials, Yttria Stabilized Zirconia showed better mechanical properties such as elongation (EL) of 6.25%, tensile strength TS of 106.06MPa and yield strength (YS) of 90.34MPa when compared with that of the base piston metal Aluminium Alloy (Al Ai). Further, better microstructure properties were also observed for YSZ (100%) in comparison with other thermal barrier coated materials.

Carbon materials for parts of gas-turbine engines and internal combustion engines, problems and prospects

The paper presents the results of application of carbon-containing material "KARBUL" for manufacturing for internal combustion engine pistons, the technology of piston manufacturing of material "KARBUL". The authors describe the prospects for use of "KARBUL" material for small-size gas turbine engines.

Method of determining the single and two-part fuel dose injection in the Common Rail system of marine combustion engine

Marine combustion piston engines are more often equipped with common rail systems, which provide multi-part injection fuel delivery to the cylinder. Dose selection must take into account, among others, its duration, the engine speed and load torque. Practical use of a specific fuel dosing is usually preceded by a study on the test stand simulating the injection process and its dependence on the dose parameters. The authors have presented a method for the selection of these parameters in the case of one-and two-part injection in the medium speed marine engine. There has been presented the manner of creating a mathematical model of the fuel dosing during the injection and research of its characteristics in order to optimize the selection of the amount of fuel, that can be applied in the design of the CR system in the marine combustion engines.

High Temperature Fatigue Strength and Quantitative Metallography of an Eutectic Al-Si Alloy for Piston Application

Eutectic Al-Si alloys are typically used for the production of internal combustion engine pistons. A high-cycle, high-temperature fatigue characterization of AlSi12 alloy performed using specimens extracted from actual pistons is presented and discussed. Fatigue strength at 107 cycles were obtained at test temperatures of 250 °C, 300 °C and 350 °C. The fatigue strength reduction was quantified. The micro structural features were quantified by quantitative metallography and fatigue fracture surfaces inspected to identify the initiation causes.

Cylinder Pressure Patterns in the SI Engine Fuelled by Methane and by Methane and Hydrogen Blends

nternal combustion engine has been in existence for a long time, but it is still in the scope of research interests and is contained in the subject matter of numerous development studies and analyses. The paper presents basic goals of research into combustion engines. A short characteristics of piston combustion engine as an object of control and adjustment was provided. It was indicated that measurements of the working medium cylinder pressure patterns could be applied to control the performance of the engine, especially the multi-fuel one. The paper presents the results of measurements of the working medium pressure patterns in the cylinder of 1.6 dm3X16SZR engine of Opel Astra car, which was fuelled by petrol, methane, and also by methane and hydrogen blends. Substantial differences in the cylinder pressure patterns were found for the engine running on alternative fuels and on conventional fuel. An increase in the hydrogen content in the blend resulted in an increase in the maximum pressures in the engine cylinder and improvements of indicated parameters when compared with the parameters determined for the engine fuelled by pure methane.

Experimental Analysis of Local Stress State and Deformation in the Critical Area of Combustion Engine Cylinder

The article is focused on local stress simulation as well as local deformation analysis in a cylinder of piston combustion engine. Design of the exhaust pipe system has to fulfill special requirements with regard to the combined loading due to high pressures and temperatures. There is a special role of the exhaust pipe barrier, which is situated in the exhaust gas pipe. This barrier separates the main air hole from the secondary lateral auxiliary air holes. The exhaust pipe barrier seems to be a critical point of the cylinder. The finite-element analysis applied on the silumin-cast cylinder is presented in the paper in order to prove the critical places with high stress concentration. The local strength of the cylinder material was estimated using a material model based on relation between the strength and the mean distance between the secondary dendrite arms (SDAS) in the as-cast microstructure. Due to local heterogeneities there are differences in the local strength value at the various places of the microstructure. The simulation of stress distribution was performed by use of the finite-element method. Based on the relation „local stress/local strength“ the individual critical places in the cylinder were defined and located.

Effect of Stress-strain State during Helical Rolling on Metal and Alloy Structure and Ductility

A working hypothesis is proposed for the mechanism of the effect of deformation regimes on granular structure and phase fineness governing an increase in ductility for silumins and low-alloy steels. In particular, an alternating nature of deformation during helical rolling (HR) provides a reduction in grain size by a factor of 5-6 compared with longitudinal rolling. For hypereutectic silumins with HR it is possible to obtain a polygonized subgranular structure, to increase α-solid solution grain and silicon crystal fineness, giving them a globular shape, and thereby provide a capacity for treatment under pressure. An important role in increasing deformation capacity of silumins is played by the new technology of melt modifying treatment and optimum temperature-rate deformation regimes. strength ( σ u = 190-320 MPa; σ 0.2 = 155-260 MPa, E = 75-80 GPa; σ -1 = 90-130 MPa). In a cold condition, relative elon- gation δ is not more than 1%, and relative reduction of area ψ is up to 4%. Strength properties of silumins are maintained to T = -70°C. Silumins have typically good production and user properties: high fluidity, low shrinkage during solidification; good weldability, high corrosion resistance, heat and wear resistance; low linear thermal expansion coefficient; nonmagnetic nature (1). Technology for preparing high silicon master alloys, based on a carbothermal reduction method of cheap and widespread raw material (nepheline, alunite, kaolin, etc.) makes it possible to reduce silumin cost by 15-20% compared with the currently used technology for synthesizing aluminum with silicon. Hypereutectic silumins may be considered as natural composite materials, having a two-phase structure consisting of ductile eutectic matrix and brittle primary silicon crystals with a size of not more than 150 μm, and also crystals of iron, titanium, and zirconium aluminides (intermetallic phases). An increase in phase fineness, playing the role of a filler, promotes an increase in both strength and ductility. Silumin alloys after processing SiC and Al 2 O 3 powders have high strength (σ u = = 650-700 MPa). Objects of high-silicon hypereutectic silumins because of their low ductility are prepared by molding and centrifu- gal casting (pipes) and liquid stamping, for example, production of internal combustion engine pistons. Further expansion of the range of these applications is connected with the solution of the problem of increasing alloy workability, development, and introduction of forming technology.

Research of Internal Combustion Engine Piston Skirt Profile Line Effect Based on Dynamics and Tribological Coupling Model

This paper mainly based on the coupling relationship between tribological and dynamic behaviors of cylinder liner-piston system to establish dynamics and tribology coupling model of cylinder linerpiston-piston ring, and to analyze the effect of piston skirt profile based on it, providing theoretical basis for determining the effect of piston skirt profiles to piston dynamics and lubrication performance.

Research and Application of Warm Extrusion Forming Technology for Internal Combustion Engine Piston Head

In order to improve the performance of the piston head on the existing conditions, and the warm extrusion forming technology was put forward based on the internal combustion engine piston head traditional production process. The warm extrusion process scheme and finite element boundary conditions was designed reasonable based on research the piston head forming process, the thermal-mechanical coupling model was established. The numerical simulation of the warm extrusion forming was carried out on the DEFORM software platform. The distributions of warm extrusion forming process strain field, stress field and temperature field were forecasted through the theoretical calculation and simulation. And the production equipment tonnage and die structure form were determined preliminarily. The possible problems of forming process were discussed, and the countermeasures were also put forward, provide the reliable reference for internal combustion engine piston head forming process improvement.

Free-piston engine-and-hydraulic pump for railway vehicles

Purpose. The development of the free-piston diesel engine-and-hydraulic pump for the continuously variable hydrostatical transmission of mobile power vehicles. Methodology. For a long time engine builders have been interesting in the problem of developing free piston engines, which have much bigger coefficient of efficiency (40…80%). Such engines don’t have the conversion of reciprocating motion for inner combustion engine piston into rotating motion of crankshaft, from which the engine torque is transferred to the power machine transmission. Free-piston engines of inner combustion don’t have the crank mechanism (CM) that significantly reduces mechanical losses for friction. Such engines can be used as compressors. Free-piston engine compressor (FPEC) – is a free-piston machine in which energy received from engine’s cylinder is being transferred direct to compressor’s pistons connected with operational pistons of engine without crank mechanism. Part of the pressed air is being consumed for engine cylinder drain and the other part is going to the consumer. Findings. The use of free-piston engines-and-hydraulic pumps as power-transmission plants of power vehicles (diesel locomotives, combine harvester, tractors, cars and other mobile and stationary power installations) with the continuously variable transmissions allows cost effectiveness improvement and metal consumption reduction of these vehicles, since the cost effectiveness of FPE is higher by 25-30%, and the metal consumption is lower by 40-50%. Originality. One of the important advantages of the free-piston engines is their simplicity and engine balance. As a result of the crank mechanism absence their construction is much simplified and the vibrations, peculiar to the ordinary engines are eliminated. In such installation the engine pistons are directly connected through the rod to compressor pistons and therefore there are no losses in the bearing bushes. Practical value. The free-piston engines are now used only as gas generators and diesel compressors, and the hydraulic transmission is arranged with the ordinary heat-engine, which operates the hydraulic pumps.

Active Data Maps of Control Unit for Racing Motorcycle

The current engine management of the four-stroke piston combustion engine require a continual distribution of the operational information. From this reason it is necessary to control the correctness of these data all the time. In order to realise this control process it should be applied the special software, which enables reading of the data fields and in this way it contributes to a faster and more correct distribution of the active measured values.

SYMPTOMS OF STATES INCLUDED IN THE PERFORMANCE OF CON-ROD-PISTON COMBUSTION ENGINES SYSTEMS

The following article describes energetic states symptoms, included in correct and incorrect performance of crankpiston combustion engines systems. Special attention has been paid to accompanying processes of such performance, with regard to, heat generation effect in combustion chamber and friction in joined frictional movements. Combustion chamber is a moving space formed by connection of the piston through piston rings with the cylinder liner and the engine head. Heat generation process takes place above the piston, generated by burning of fuel. It causes an increase of gas pressure in the combustion space, which results in the movement of the piston tightened by the rings, followed by an increase of the space volume. In this way energy is emitted from fuel burning, influencing the elements of piston-conrod system in the form of heat and work. The ability of such thermodynamical system to convert energy into an effective one is limited. Internal energy of exhaust gases can be divided into the part which cannot be converted into work. The process of heat generation in engine cylinder is of irreversible character which results in the loss of energy. In piston combustion engines, work is performed by heat generated in cylinders. Energetic performance in piston-crank system results from internal exchange of exhaust gases in combustion chamber with the engine surroundings. Analysis of such energetic performances allows us to isolate symptoms of correct operation of piston con-rod combustion engine systems. Such symptoms include: exhaust gases temperature, temperature of piston surface, momentary values of torque and the speed of pressure increase during combustion. Piston-con-rod system is a component part of the engine. Evaluation of its performance allows to identify the present technical condition of the engine. Diagnostic advantages of some, above mentioned symptoms of piston-con-rod combustion engine operation, have been verified by means of adequate laboratory testing and during engine operation on the ship.