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Ibron E-Spik Ex
A numerical study of mixing phenomena and reaction front propagation in partially premixed combustion engines Ibron, Christian 2019 Document Version: Publisher's PDF, also known as Version of record Link to publication Citation for published version (APA): Ibron, C. (2019). A numerical study of mixing phenomena and reaction front propagation in partially premixed combustion engines. Department of Energy Sciences, Lund University. Total number of authors: 1 Creative Commons License: Unspecified General rights Unless other specific re-use rights are stated the following general rights apply: Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Read more about Creative commons licenses: https://creativecommons.org/licenses/ Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. LUND UNIVERSITY PO Box 117 221 00 Lund +46 46-222 00 00 CHRISTIAN IBRON CHRISTIAN A numerical study mixing -
Desmodromics Mick Walker Explains How Ducati Beat Tbe World with Spring-Less Valve Operation
og , Desmodromics Mick Walker explains how Ducati beat tbe world with spring-less valve operation HE WORD desmodmmic wil! not be the bounce and get a higher-revving engine successful and was not developed, but in found in the Oxford or any other - in theory. the 1920s several other manufacturers tried T English dictionaries. It was coined This had been known since the early days variants of it. One layout, the Vagova, from two Greek words, meaning 'controlled of the internal combustion engine but for utilized a cam track embodying inner and run' and its mechanical function is to elimi- many years no designer managed to success- outer cam forms which guided a roller nate one of the phenomenon of valve float, fully harness it. One of the first examples of attached to one end of a 'rocker', the other or 'bounce'. This happens at high revs when completely positive mechanical valve oper- end of the rocker was forked to embrace the valve springs are unable to respond ation was used by the French Delage concern the valve stem. To provide the required quickly enough to close the valve back on in its grand prix car of 1914 - and the freedom for seating, the pivot of the rocker their seats. 11le desmodromic idea was to French knew the method as desmod- was given a small amount of spring-Ioaded replace troublesome springs with a romique. float parallel to the valve axis. me(\. jcal closing system much like that The Delage engine employed four valves Alternative methods investigated were to usedló open them. -
Effect of Using Biodiesel As a Fuel in C I Engine
International Journal of Engineering Science Invention ISSN (Online): 2319 – 6734, ISSN (Print): 2319 – 6726 www.ijesi.org ||Volume 5 Issue 7|| July 2016 || PP. 71-81 Effect of Using Biodiesel as a Fuel in C I Engine Swagatika Acharya1, Tatwa Prakash Pattasani2, Bidyut Prava Jena3 1,2Assistant Professor, Department of Mechanical Engineering, Gandhi Institute For Technology (GIFT), Bhubaneswar 3 Assistant Professor, Department of Mechanical Engineering, Gandhi Engineering College, Bhubaneswar Abstract: Biodiesels are fuels that are made from renewable oils that can usually be used in diesel engines without modification. These fuels have properties similar to fossil diesel oils and have reduced emissions from a cleaner burn due to their higher oxygen content. The present work investigates the performance of three types of biodiesel and diesel fuels in a Mitsubishi 4D68 4 in-line multi cylinder compression ignition (CI) engine using transient test cycle. The test results that will obtain are brake power, specific fuel consumption (SFC), brake thermal efficiency and exhaust emissions. An instrumentation system also will be developed for the engine testing cell and controlled from the control room. Biodiesel was also tested against diesel fuel in Exhaust Gas Recirculation (EGR) system. Thus it is possible that biodiesel fuels may work more effectively than fossil diesel in certain applications. Keywords: Biodiesel, CI engine, transient, Instrumentation, EGR I. Introduction Biodiesel, is the generic terms for all types of Fatty Acid Methyl Ester (FAME) as one among other organic renewable alternative fuel that can be used directly in any conventional diesel engine without modification. They are transesterified vegetable oils that have been adapted to the properties of fossilized diesel fuel and considered to be superior since they have a higher energetic yield been combusted in the diesel engine (Adams 1983) . -
A Camshaft Non-Linear Model for the Desmodromic Valve Train Simulation
A Camshaft Non-Linear Model for the Desmodromic Valve Train Simulation A. Rivola, *A. Carlini DIEM – Mechanical Engineering Department, University of Bologna viale Risorgimento, 2 – I40136, Bologna, Italy email: [email protected] *Test Bench Engineer, DucatiCorse s.r.l., via Cavalieri Ducati, 3 – I40132, Bologna, Italy Abstract In this paper the dynamic behaviour of the desmodromic valve train of a motorbike engine is simulated and analysed. The valve train model takes into account the mass distribution, the link elastic flexibility, and the presence of several non-linearities. The camshafts, which are supported by hydrodynamic journal bearings, are modelled by means of finite rotating elements based on Timoshenko beams with the effect of gyroscopic moment. The non-linear bearing forces are analytically obtained under the finite-length bearing assumption. The comparison between the numerical results and the experimental data – in terms of valve acceleration and camshaft angular velocity – shows that the effectiveness of the model is satisfactorily assessed. The paper mainly focuses on two points: the validation procedure of the finite element model of the camshafts, and the study of the simulated camshaft centreline trajectories. 1 Introduction This paper deals with a kineto-elastodynamic model of the desmodromic valve train of a Ducati motorbike engine. The desmodromic train is a mechanism with positive-drive cams and – in comparison with the widely-used trains having a closing spring [1–3] – presents different dynamic behaviour, as shown in [4– 7]. When operating at high-speed, a mechanism shows a dynamic behaviour which is affected by the link elastic flexibility and mass distribution, as well as the effects of backlashes and friction in joints. -
3.0 ACTUAL ENGINE CYCLE Reciprocating Internal Combustion
3.0 ACTUAL ENGINE CYCLE Reciprocating internal combustion engines operate on actual engine cycles, which are classified mainly into two groups: (i) Spark Ignition engines and (ii) Compression Ignition engines and these classifications are dependent on the mode of the ignition of the air/fuel mixture (charge) in the cylinder. The spark ignition engines operate based on the Otto cycle principle while the compression ignition engines operate basically on the Diesel cycle principle. The sequence of operations required by a reciprocating engine to perform a mechanical work could either be two or four strokes of engine piston motion which translates to one or two crankshaft revolution respectively. The piston of a reciprocating internal combustion engine could be termed as double acting (as seen in steam engines) or single acting (as is seen in most reciprocating internal combustion engines). If the engine cycle of operation takes place in only one side of the piston, its termed single acting while it is termed double acting when the cycle takes place on both sides of the piston. For an internal combustion engine to be efficient the following requirements are to be met: The mixture of fuel and air in the engine cylinder must be in the right proportion. Compression must take place on the mixture of air and fuel or air only before the addition of fuel (this is dependent on the engine cycle operation). The compressed mixture is to be ignited (which could be through the introduction of spark or auto-ignition) and the expanding combustion products used to drive the engine. -
Design of an Effective Timing System for ICE
Design of an Effective Timing System for ICE Andrea Miraglia∗ and Giuseppe Monteleoney yDepartment of Electrical, Electronics, and Informatics Engineering, University of Catania, Catania Italy ∗Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud, Catania Italy Abstract—The present paper describes the design and the a four-stroke engine, generally conical valves are employed; prototype realization process of a new effective timing system they open under the action of cams, fitted on the camshaft par- for ICE (internal combustion engine). In particular, the present allel to and activated by the crankshaft, subsequently closing paper outlines the dynamic behavior and related performance of the innovative timing system applied to a two cylinder engine. at the position due to the push by appropriate calibrated coil The procedure to validate the prototype, based on experimental springs [1], [2], [3], [4], [5]. tests carried out on a test bench, is presented and discussed. The traditional finite elements method and computational fluid A. The main timing elements dynamics (CFD) analysis are used to estimate the dynamic performance of the engine with the new timing system. The The main elements of a timing system are: comparison with the data reported in bibliography shows the • Camshaft effectiveness of the new timing system. The study indicates that the proposed system is of great significance for the development • Valves (guides, seals and springs) of timing system in an automotive engine. • Tappets • Pushrods Keywords-Specific power; Computational dynamic analysis; 3D modeling; CFD analysis; Reliability. • Rocker arms The most common valve train system involves pushrods I. INTRODUCTION and rocker arms; however, there are other valve train systems The idea of a new timing system originated from the passion available, offering such solutions as single or double camshaft. -
Modelling the Elastodynamic Behaviour of a Desmodromic Valve Train
Modelling the Elastodynamic Behaviour of a Desmodromic Valve Train Alessandro RIVOLA (*), Andrea CARLINI (*), and Giorgio DALPIAZ (**) (*) DIEM - University of Bologna Viale Risorgimento, 2, I - 40136 Bologna, Italy e-mail: [email protected] (**) Dept. of Engineering, University of Ferrara Via Saragat, 1, I - 44100 Ferrara, Italy e-mail: [email protected] Abstract This paper deals with a lumped-parameter model of a motorbike engine’s desmodromic valve train. The model of such an uncommon cam system is developed and validated with the aid of experimental measurements carried out on a test bench which operates the cam mechanism by means of an electrically powered driveline. The model describes the mechanical system taking into account the mass distribution, the link elastic flexibility, and the presence of several non-linearities. The model parameter estimation is discussed and the effectiveness of the model is assessed by a comparison with experimental results. In addition, the model is employed to estimate the magnitude of contact forces and to predict the system behaviour as a consequence of changes in some design parameters; therefore, it may be used as a tool both in design optimisation and diagnostics. 1 Introduction train of a Ducati motorbike engine. Only works on widely-used trains with closing spring were found in Nowadays the study of the dynamic response of literature [7–9]; in those cases the valve spring plays flexible mechanisms operating at high speed is an important role in the system dynamics. becoming more and more important and several Conversely, in the case of desmodromic valve trains studies can be found in literature [1–4]. -
19FFL-0023 2-Stroke Engine Options for Automotive Use: a Fundamental Comparison of Different Potential Scavenging Arrangements for Medium-Duty Truck Applications
Citation for published version: Turner, J, Head, RA, Chang, J, Engineer, N, Wijetunge, RS, Blundell, DW & Burke, P 2019, '2-Stroke Engine Options for Automotive Use: A Fundamental Comparison of Different Potential Scavenging Arrangements for Medium-Duty Truck Applications', SAE Technical Paper Series, pp. 1-21. https://doi.org/10.4271/2019-01-0071 DOI: 10.4271/2019-01-0071 Publication date: 2019 Document Version Peer reviewed version Link to publication The final publication is available at SAE Mobilus via https://doi.org/10.4271/2019-01-0071 University of Bath Alternative formats If you require this document in an alternative format, please contact: [email protected] General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Download date: 27. Sep. 2021 Paper Offer 19FFL-0023 2-Stroke Engine Options for Automotive Use: A Fundamental Comparison of Different Potential Scavenging Arrangements for Medium-Duty Truck Applications Author, co-author (Do NOT enter this information. It will be pulled from participant tab in MyTechZone) Affiliation (Do NOT enter this information. It will be pulled from participant tab in MyTechZone) Abstract For the opposed-piston engine, once the port timing obtained by the optimizer had been established, a supplementary study was conducted looking at the effect of relative phasing of the crankshafts The work presented here seeks to compare different means of on performance and economy. -
Combustion Thermodynamics of Ethanol, N-Heptane, and N-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System
energies Article Combustion Thermodynamics of Ethanol, n-Heptane, and n-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System Ireneusz Pielecha 1,* , Sławomir Wierzbicki 2,* , Maciej Sidorowicz 3 and Dariusz Pietras 4 1 Department of Combustion Engines and Transport, Faculty of Civil and Transport Engineering, Poznan University of Technology, pl. M. Sklodowskiej-Curie 5, 60-965 Poznan, Poland 2 Department of Mechatronics, Faculty of Technical Sciences, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 11, 10-710 Olsztyn, Poland 3 AC S.A., ul. 42 Pulku Piechoty 50, 15-181 Białystok, Poland; [email protected] 4 Department of Combustion Engines and Vehicles, Faculty of Mechanical Engineering and Computer Science, University of Bielsko-Biala, ul. Willowa 2, 43-309 Bielsko-Biała, Poland; [email protected] * Correspondence: [email protected] (I.P.); [email protected] (S.W.) Abstract: The development of internal combustion engines involves various new solutions, one of which is the use of dual-fuel systems. The diversity of technological solutions being developed determines the efficiency of such systems, as well as the possibility of reducing the emission of carbon dioxide and exhaust components into the atmosphere. An innovative double direct injection system was used as a method for forming a mixture in the combustion chamber. The tests were carried out with the use of gasoline, ethanol, n-heptane, and n-butanol during combustion in a model test engine—the rapid compression machine (RCM). The analyzed combustion process indicators included the cylinder pressure, pressure increase rate, heat release rate, and heat release value. -
External Combustion Engines: Prospects for Vehicular Application
EXTERNAL COMBUSTION ENGINES: PROSPECTS FOR VEHICULAR APPLICATION Roy A. Renner, California steam Bus Project, International Research and Technology Corporation, San Ramon, California External combustion engines are discussed as possible alternatives to the internal combustion engine for vehicle propulsion. Potential advantages are low levels of exhaust pollution, quiet operation, high starting torque, and possible lower costs during a vehicle lifetime. Present experience with the California steam Bus Project indicates that competitive road per formance is obtainable with steam-powered city buses, but fuel consump tion is higher than with a diesel engine. Opportunities remain open for the evolutionary improvement of thermal efficiency. Logical early applica tions include stop-and-go fleet vehicles. •GASOLINE and diesel engines have been preferred prime movers for motor vehicles during a period of many years. Despite the almost universal application of the internal combusion engine (ICE), the criteria for vehicular power plants are now being seriously reexamined. Alternatives to the ICE are being reconsidered in a new light (1, 2). The external combusion engine (ECE), of which the steam engine is the best known 0 xample, has been in use for more than 200 years. steam power was popular for auto- _obiles at the turn of this century. Prior to 1910, it was considered to be superior to the ICE for automobile propulsion in every way except first cost and convenience. Even then, the steam car was noted for its quietness and clean exhaust; freedom from gear shifting was also a decided advantage. Now that air pollution, noise, and congestion are factors no longer to be ignored, both the role of the vehicle and its source of power are being evaluated anew. -
Dynamic Balance of a Single Cylinder Reciprocating Engine with Optical Access
DYNAMIC BALANCE OF A SINGLE CYLINDER RECIPROCATING ENGINE WITH OPTICAL ACCESS By Trevor W. Ruckle A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Mechanical Engineering – Master of Science 2014 ABSTRACT DYNAMIC BALANCE OF A SINGLE CYLINDER RECIPROCATING ENGINE WITH OPTICAL ACCESS By Trevor W. Ruckle The balance within reciprocating engines has always been a concern of engine designers. Any unbalance within an engine can result in component fatigue and failure, excessive vibration, and radiated noise (airborne and structural). When an engine is created with optical access, a Bowditch piston is placed on top a standard piston. This results in the reciprocating mass being significantly greater, and it greatly increases the reciprocating force. The components that affect the balance of the engine were identified and different design aspects within each component that affect the balance were explored. The calculations that were used to calculate static and dynamic balance of the system and how these affect the design of our engine were investigated. Practical techniques were demonstrated to validate the balance of each component after they had been fabricated. Through testing, the first and second order balance effects were analyzed and the harmonic resonances within the system were identified. The interactions between the harmonic resonances and the first and second order forces were also explored. ACKNOWLEDGEMENTS I’d like to take this opportunity to thank the many individuals who have, so graciously, helped me with this research project. I would like to thank Harold Schock for acting as my advisor and supporting me during my master’s program; Dr. -
Assessment of Combustion Modes for Internal Combustion Wave Rotors
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by IUPUIScholarWorks Assessment of Combustion Modes for Internal Combustion M. R. Nalim1 Wave Rotors National Research Council, NASA Lewis Research Center, Combustion within the channels of a wave rotor is examined as a means of obtaining Cleveland, OH pressure gain during heat addition in a gas turbine engine. Three modes of combus tion are assessed: premixed autoignition (detonation), premixed deflagration, and non-premixed autoignition. The last two will require strong turbulence for completion of combustion in a reasonable time in the wave rotor. The autoignition modes will require inlet temperatures in excess of 800 Kfor reliable ignition with most hydrocar bon fuels. Examples of combustion mode selection are presented for two engine applications. Introduction Among its many applications (Shreeve and Mathur, 1985), the wave rotor in a gas turbine engine can increase its pressure The internal combustion wave rotor is a promising means ratio and peak cycle temperature beyond the limits of turboma- of pressure-gain combustion. It approaches the thermodynamic chinery. It can utilize external (i.e., conventional, steady flow) ideal of constant-volume combustion, and can provide signifi combustion or internal (on rotor) combustion. This distinction cant enhancement of gas turbine engine performance and NOx is made with reference to the wave rotor; in the thermodynamic emissions reduction. Pressure-gain combustion has been a long sense, combustion is always internal, i.e., within the working sought ideal. Indeed, the earliest working gas turbines had fluid. Past approaches have generally proposed external com valved, pulsating combustion chambers (Foa, 1960).