Combustion Engine Piston Research Articles

Complex analysis focused on influence of biodiesel and its mixture on regulated and unregulated emissions of motor vehicles with the aim to protect air quality and environment

The main task of this study is to perform a complex analysis dealing with influence of biodiesel and its mixture on regulated and unregulated gaseous emissions of diesel engine, which is installed in a motorcar as a driving unit determined for standard road traffic. As a real technical platform intended for realisation of the required experiments, a motor vehicle equipped with the TDI engine was chosen because just this kind of engine was directly affected by the affair “dieselgate”. This type of piston combustion engine is widely used in the traffic, together with negative impacts on the air quality. Various diesel fuel mixtures, which represented the applied experimental fuels, were created by mixing of the ultra-low sulphur diesel fuel (ULSDF) with the biodiesel, using different mixture ratios. The individual experiments were performed during a 13-mode test cycle especially developed for the diesel engine in such a way, so that it was possible to identify influence of the engine loading and engine speed on the regulated and unregulated gaseous emissions of the given TDI diesel engine. It is possible to say according to the obtained results that a higher portion of the biodiesel in the fuel mixture reduces the amount of the hydrocarbons (HC), carbon monoxide (CO) and particulate matters (PM) in the gaseous emissions, but it increases volume of the nitrogen oxides (NOX). A higher portion of the biodiesel causes a growth of the formaldehyde emissions and acetaldehyde emissions in the case of unregulated diesel engine emissions. The same trend is also typical for the 1,3-butadiene, propene and ethene. The biodiesel additive increases emissions of benzene; however, it reduces emissions of the toluene and xylene within the aromatic substance emissions. The obtained results confirm a fact that all the gaseous emissions are influenced by the engine operational regimes, especially by the engine loading status.

Microstructural Characteristics, Mechanical Properties, Fracture Analysis and Corrosion Behavior of Hypereutectic Al–13.5Si Alloy

Hypereutectic Al–13.5Si alloy containing 1.47% of copper and 1.30% of magnesium was designed as a potential material for internal combustion engine pistons. The optical microscopy and scanning electron microscopy (SEM) revealed the fine dendrites of α-Al phase and significantly dispersed eutectics in as-cast specimens. Several intermetallic phases were observed indicating different crystallization velocities and alloy composition nonuniformities. The tensile testing and hardness measurements performed at room temperature have shown an excellent tensile strength and hardness of as-cast specimens, but low elongation due to a complex multiphase structure. The mechanical examinations at 250 °C and 300 °C have presented a decrease in tensile strength and an increase in elongation, while hardness was slightly changed. The fractographic analysis has shown the features of the brittle as well as ductile fracture. The areas of dimples and areas containing particles with smooth surfaces were detected. Electrochemical methods, Tafel linear polarization, cyclic voltammetry, chronoamperometric measurement and impedance spectroscopy were employed to determine the corrosion behavior of as-cast specimens in 0.5 M NaCl solution. The resistant oxide layer formed on the surface was not entirely consistent due to the appearance of intermetallic phases. SEM examinations of corroded samples did not discover severe pits on their surfaces.

Options for using solid oxide fuel cell technology in complex integrated biomass gasification cogeneration plants

The aim of this paper is to draw readers' attention to potential new technological solutions for effective utilisation of dispersed biomass resources in distributed community-scale applications. In the paper conceptual system, that consists of allothermal wood gasifier, solid oxide fuel cell (SOFC), internal combustion piston engine (ICE) and Organic Rankine Cycle (ORC) for waste heat recovery, is proposed. Configuration of such systems is nowadays possible due to availability individual small-scale energy conversion technologies that can be integrated into complex structures. In the studied case the anode exhaust gas of the syngas fired SOFC module, that still contains combustible gases, is considered a secondary fuel for a bottoming ICE. The ORC cycle module is driven by the heat recovered from process gas coolers as well as from SOFC cathode and ICE exhaust gases. The system has been theoretically evaluated in terms of energy conversion efficiency and profitability using thermodynamic and economic analysis. Relevant robust mathematical models of key components have been developed. Through the modelling the most important performance parameters are addressed. Electric power of the sample system is below 1 MW what makes it suitable for utilisation of locally available biomass. Simulations revealed potentially high value of the net biomass energy to electricity conversion efficiency of 37%–40% depending on the ORC cycle configuration. Financial analysis revealed positive values of profitability indices at current level of market prices. The results are compared with a real biomass-fired ORC cogeneration project. The system also addresses issues related to external effects of the project, such as global emission reduction and primary energy savings.

Analysis of Influence of the Atmospheric Conditions and Temperature Range in the Exhaust Pipe on the Output Engine Characteristics

The piston combustion engine, which is working on the HCCI technology principle, is very sensitive to changes of the external atmospheric conditions. These changes are immediately influencing the engine power characteristics. At best only they effect decreasing of the maximum engine power. However, in a more difficult situation, there is the possibility of excessive detonation combustion process during certain changes in atmospheric conditions. The exhaust system temperature significantly affects the maximum output power and the combustion engine characteristics. With increasing temperature of combustion products in the exhaust system there is an overall reduction in maximum power and its transfer to a higher engine speed because of the length of an exhaust manifold is theoretically shorten. Therefore, to achieve the maximum values of output parameters, it is necessary to ensure an optimal temperature value of the combustion products in the exhaust system. This article also provides optimal temperature range of working temperature as well as it presents a theoretical analysis of the impact for atmospheric conditions in this interval. Based on theoretical results there has been developed a measuring method, which allows to regulate the input amount of the fuel mixture supplied to a cylinder during change in atmospheric conditions and its functionality was experimentally verified.

Numerical Analysis of the Effect of Piston Cooling Gallery Design on Heat Transfer in an Internal Combustion Engine

Internal combustion engines are important machines that make human life easier. Internal combustion engines are developing day by day and higher power density engines are produced. Besides, strict standards of emission and fuel economy are forcing automotive manufacturers to produce environment-friendly engines. While manufacturers produce engines in accordance with these standards, they also do various studies in order not to reduce performance. One of the most important of these studies is the development of thermal management. Good cooling of internal combustion engine pistons, which are exposed to high pressures and temperatures during the combustion process, is an important consideration for the development of the thermal management. In this study; it is aimed to investigate the effect of design differences on piston cooling by using different designs for the cooling gallery located in the head region of an internal combustion engine piston. For this purpose, thermal analysis of an internal combustion engine piston was performed for different cooling gallery designs and the results of the analysis of each design were compared. In addition, the results of the analysis were compared with the heat transfer rates in the literature.

TOPOLOGY OPTIMIZATION OF INTEGRATED COMBUSTION ENGINE PISTON USING FEA METHOD (CAE TOOLS)

Topology optimization is a numerical approach that optimizes material arrangement within a given design space, for a given set of loads and periphery conditions such that the resulting layout meets a approved set of concert targets. Using topology optimization, engineers can find the best perception design that meets the design necessities. Topology optimization has been developed through the use of finite element methods of the analysis, and optimization techniques based on the method of moving asymptotes, genetic algorithms, optimality criteria method, level sets, and derivatives. Topology optimization is used at the idea level of the design process to appear at an intangible design plan that is then fine-tuned for concert and manufacturability. This thesis work correlated to the lay out optimization of internal combustion engine piston. Piston is one of the significant apparatus of engine. The multiple type of piston using through the automobile sectors. The various different type of piston is i) Equivalents lands thickness piston ii) Without crown piston (flat piston), iii) Without undercut piston, iv) With skirt land piston v) Dissimilar land thickness the analyzed this research work the Computer Aided Designing model initially created by CATIA, then Finite Element Analysis done by ANSYS.

Performance indices of a common rail-system CI engine powered by diesel oil and biofuel blends

Conventional fuels used for supplying internal combustion piston engines include petrols and diesel oils produced from petroleum. These are a non-renewable energy source. The environmental policy of the European Union is geared towards increasing the share of renewable fuels in the overall energy consumption. An alternative fuel originating from a renewable source, which could be used for feeding self-ignition internal combustion engines are the fatty acid methyl esters (FAME) of plant oils. The paper reports selected results of testing a 1.3 MULTIJET SDE 90 PS self-ignition engine with the Common Rail reservoir feed system supplied with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME). Tests were carried out on an engine test bed equipped with an eddy-current brake. The purpose of the tests was to determine the economic–energy and ecological indices of engine operation. The concentrations of exhaust gas gaseous components were measured using a MEXA-1600DEGR analyzer, while the particulate concentrations, with a MEXA-1230PM analyzer. In addition, the variations of working medium pressures in the engine chamber and of fuel pressure upstream the injector were recorded as a function of crankshaft rotation angle using the AVL IndiSmart 612 indication system for this purpose. The physicochemical properties of fuels used in the tests were determined using a fuel analyzer. The obtained testing results made it possible to determine and assess the operation indices of the engine fed with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME) with slightly higher ester contents than the requirements of the currently applicable diesel oil standard.

Wear Evaluation of Engine Piston Rings Coated With Dual Layer Hard and Soft Coatings

The main objective of this investigation is the evaluation of the performance of hard diamond-like-carbon (DLC) or tungsten carbide (WC) and soft (epoxy composite) dual-coatings on the internal combustion (IC) engine piston rings as a protective coating to reduce their wear. The rings were coated with DLC or WC by physical vapor deposition (PVD) method and then soft polymeric composite coating (epoxy/graphene/base oil SN150) was applied on the hard coating. The tribological tests of the dual-coated piston rings were conducted for 3.6 × 105 cycles at 1500 rpm engine speed and 50% rated load of a diesel engine in order to evaluate the wear performance of the piston rings. Scuffing of cylinder liner and piston rings interface was prevented by the application of polymer composites over the hard-coated rings. DLC hard and soft polymer composite dual coating over the top piston ring was found to have the lowest wear rate 1.69 × 10−12 mm3/N·m compared with the wear rate of dual coatings on the middle and lower rings.

The impact of modern constructional solutions of internal combustion engines upon ecological safety of their application

Piston combustion engines used for propelling vehicles have a significantly harmful impact upon people’s living environment. As a result, for many years now the development of combustion engines has been to a large extent defined by growing legal ecological requirements. New constructional solutions are being introduced, the conditions of working processes in engine cylinders are being changed, new solutions are being implemented in fuel feeding systems, air intake systems and fumes exhaust. The composition of conventional fuel is being modified, alternative fuels are being sought for and new types of powering systems are being developed. This paper presents the comparison of selected efficiency and ecological indicators of two engines having the same construction, but different in the type of powering and the method of controlling the process of supplying fuel and air into cylinders. One of the engines is Perkins 1104D-44TA, mechanically controlled and equipped with a feeding system with distributor injection pump. The second one is the Perkins 1104D-E44TA, electronically controlled, where fuel is supplied into the cylinders by means of the Common Rail system. During the tests, the engines operated according to two load characteristics. Hourly and specific fuel consumption as well as concentration levels of main components of exhaust fumes and smokiness have been iden-tified and compared.

Design Optimization Study of a Nonlinear Energy Absorber for Internal Combustion Engine Pistons

Piston impacts against the cylinder liner are the most significant sources of mechanical noise in internal combustion (IC) engines. Traditionally, the severity of impacts is reduced through the modification of physical and geometrical characteristics of components in the piston assembly. These methods effectively reduce power losses at certain engine operating conditions. Frictional losses and piston impact noise are inversely proportional. Hence, the reduction in power loss leads to louder piston impact noise. An alternative method that is robust to fluctuations in the engine operating conditions is anticipated to improve the engine's noise, vibration and harshness (NVH) performance, while exacerbation in power loss remains within the limits of conventional methods. The concept of targeted energy transfer (TET) through the use of nonlinear energy sink (NES) is relatively new and its application in automotive powertrains has not been demonstrated yet. In this paper, a TET device is conceptually designed and optimized through a series of parametric studies. The dynamic response and power loss of a piston model equipped with this nonlinear energy sink is investigated. Numerical studies have shown a potential in reducing the severity of impact dynamics by controlling the piston's secondary motion.

Optimization of Internal Combustion Engine Piston

Optimization of Internal Combustion Engine Piston

System based on thermal control of the HCCI technology developed for reduction of the vehicle NOX emissions in order to fulfil the future standard Euro 7

On the present the environmental protection belongs among the most important worldwide priorities. From this reason there is valid within the framework of the European Union the standard Euro, which is specifically defined in the transport area. Nowadays the actual issue of this standard is signed Euro 6. It is established in order to eliminate most of the undesirable air pollutants. However, there is already prepared a new and even stricter emission standard Euro 7. It is a well-known fact that the actual emission standards are very hard and the automobile factories, together with the engine design concepts are trying to fulfil the new emission standards, mainly the NOX emission requirements. These circumstances also caused the infamous affair “dieselgate”. The new engine concept, which is called HCCI (Homogeneous Charge Compression Ignition), could be a suitable solution of the present NOX emission problems. Principle of the HCCI technology is based on self-ignition of the homogenous fuel mixture using compression in order to reduce emissions, whereas the NOX emission level is almost negligible. However, there are also several essential problems connected with the above-mentioned innovative technology, for example a high level of pressures arising during the compression process and intensive heat release. Another serious problem is a complicated control of the self-ignition process. This article presents an original technical solution, which enables to regulate the whole self-ignition process and in this way to ensure a reliable operation of the HCCI engine. We would like to emphasize also a fact that this unique solution was applied for a patent, as well. The innovated piston combustion engine was installed in the experimental vehicle designed for participation at the international competition shell eco marathon 2018 in London focused on minimisation of the fuel consumption.

Diagnosis of EMD645 diesel engine connection rod failure through modal testing and finite element modeling

Abstract Connection rods are best known through their use in internal combustion piston engines. GM-GT26 locomotive uses a 3300 horse power V type engine with 16 cylinders that works at maximum crank speed of 900 RPM. The present study is concerned with the failure of a 645E3B engine connection rod with a reported catastrophic deformation due to unknown reasons. This rod has suffered from simultaneous bends in two surfaces with obvious marks of failure. A theoretical procedure, an experimental modal analysis technique and simulation by using finite element engineering softwares are used for this study. It includes finding the natural frequencies and the corresponding mode shapes for a new connection rod. This is then used to validate the FEM simulated model. The critical loads and the buckling forces on the connection rod are then calculated. The maximum loads are calculated by using the classical approaches and are verified by simulation in ADAMS-Engine software. The dynamic modeling includes rigid and flexible beam models and the torsional modes of vibrations are also considered. It is concluded that the connection rod failure is due to buckling at the presence of hydrolock phenomenon. The outcome of this research provides vital information for the proper operation and maintenance of heavy duty Diesel engines.

Influence of Lubricating Oil Improvers On Performance of Crankshaft Seals

Abstract This paper presents an original method for checking influence of lubricating oil improvers on performance of crankshaft seals of combustion piston engine. Crankshaft seals were tested with the use of a modified friction node of T-02 four-ball apparatus in laboratory conditions. The tests were conducted according to a worked-out algorithm. Their results confirmed usefulness of the method for determining „harmful” performance of sealing systems, which makes it possible to assess operational usability of lubricating oil improvers. On the basis of an analysis of the results a scientific hypothesis saying that lubricating oil quality affects correctness of performance of crankshaft seals of combustion piston engine, was formulated. The hypothesis was verified by means of induction inference and statistical method with taking into account Fisher statistics.

Piston kinematics of a combustion engine with unconventional crank mechanism

The article deals with a theoretical solution of kinematic variables describing the movement of a combustion engine piston with unconventional mechanism FIK protected by patents No. 283742 and No. 283743 [1]. The course of the path, the velocity, and the acceleration were calculated to assess the dynamic properties of the unconventional mechanism, which transform the piston linear movement to rotational movement by using a swinging board, a baseboard and a crankshaft.

Possibilities to reduce emissions of nitrogen oxides from combustion engines specified for experimental vehicles

This paper is focused on the systems of fuel maps and pre-ignition maps as well as on the possibilities how to reduce emissions by tuning of these maps. The experimental research was realised using a single-cylinder small-volume piston combustion engine installed in the experimental vehicle, which was specified for the international competition Shell Eco-marathon. The main purpose of the performed research and development activities was a minimisation of the fuel consumption and reduction of the gaseous emissions. There were achieved significant positive results in this way, namely an improvement of the whole combustion process and increasing of the applied fuel efficiency by tuning of the fuel maps and pre-ignition maps. Very good results obtained by us at the international competition Shell Eco-marathon 2017 in London confirmed the above-mentioned achievements.

Possibilities to reduce emissions of nitrogen oxides from combustion engines specified for experimental vehicles

This paper is focused on the systems of fuel maps and pre-ignition maps as well as on the possibilities how to reduce emissions by tuning of these maps. The experimental research was realised using a single-cylinder small-volume piston combustion engine installed in the experimental vehicle, which was specified for the international competition Shell Eco-marathon. The main purpose of the performed research and development activities was a minimisation of the fuel consumption and reduction of the gaseous emissions. There were achieved significant positive results in this way, namely an improvement of the whole combustion process and increasing of the applied fuel efficiency by tuning of the fuel maps and pre-ignition maps. Very good results obtained by us at the international competition Shell Eco-marathon 2017 in London confirmed the above-mentioned achievements.

Features of Load and Wear of Main Propulsion Devices on Sea-Going Ships with Piston Combustion Engines and Their Impact on Changes in Technical States of the Systems

Abstract The paper presents the specificity of operation of propulsion systems of seagoing ships which causes the need to control the load on them, especially on their engines called main engines. The characteristics of the load on the propulsion systems, especially on the main engines as well as on the shaft lines and propellers driven by the engines, along with the process of wear in tribological joints (sliding tribological systems) of the machines have been described herein. Using examples of typical types of wear (both linear and volumetric) for the tribological systems of this sort, interpretation of states of their wear has been provided with regards to the wear levels defined as acceptable, unacceptable and catastrophic. The following hypotheses have been formulated: 1) hypothesis explaining necessity to consider the loads on the systems under operation as stochastic processes; 2) hypothesis explaining a possibility of considering the processes as stationary; and 3) hypothesis explaining why it can be assumed that a given technical state of any tribological system can be considered as dependent only on the directly preceding state and stochastically independent of the states that existed earlier. Accepting the hypotheses as true, a four-state continuous-time semi-Markov process has been proposed in the form of a model of changes in condition of a propulsion system (PS) of any ship. The model includes the most significant states affecting safety of a ship at sea, such as: s0 - PS ability state, s1 - PS disability state due to damage to the main engine (ME), s2 - PS disability state due to damage to the shaft line (SL) and s3 - PS disability state due to damage to the propeller (P). Probability of occurrence (changes) of the states has also been demonstrated.

Operational Degradation of Spheroidal Graphite Cast Iron EN GJS SiMo

The specifics of low-alloyed cast irons after EN 16124 standard of type GJS SiMo for high temperature applications of exhaust tracts of internal combustion piston engines. Boundary exposition temperature. Structure failure of cast iron by temperature overloading. Metalography, SEM, XRD of overexposed exhaust pipelines. Failure reason hypothesis of useful properties by exceeding of critical temperature.

Ecological analysis related to creation of gaseous emissions within transport focused on fulfilment of the future emission standards

Questions of ecology in the area of transport are always very topical because the newest emission standards concerning the piston combustion engines are very hard with regard to protection of the environment and human health. Nowadays the most often used driving units that are applied within the road transport as well as in the marine transport are the diesel engines. In the last period occurred information about a fact that in some of the motorcars was installed a software, which enabled to hide the over-limit values of the nitrogen oxides during the emission testing process. This affair is called “dieselgate”. It is a well-known fact that the actual emission limits are very hard and there is arising a serious problem for automobile factories to meet the demanding emission requirements. Therefore it was elaborated an ecological analysis or study concerning the gaseous emissions produced in the road transport. This analysis is based on application of the experimental fuels. As the experimental combustion engine it was chosen just such kind of the motorcar engine, which is relevant to the cause “dieselgate”, i.e. the diesel piston combustion engine. The testing fuels were created by mixing of the biodiesel and the ULSDF (Ultra Low Sulphur Diesel Fuel), using various mutual ratios between these fuels. The individual measurements were performed at the various engine loading levels and engine speeds in order to investigate an influence of the experimental fuels on the real operational characteristics of the given testing engine.