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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Jednoválcový motor pro silniční závodní motocykl / Single-cylinder Engine of a Road Racing Motorcycle

Švábík, Roman January 2015 (has links)
The aim of this thesis is design of one cylinder engine, with stroke volume 250ccm, for a Moto3 category racing motorbike. At the begin the thesis describes rules for engine design for Moto3 racing motorbike category and gives a summary about current technologies in engine design and motorcycle development. Another part describes construction features of engine design, completed with crank shaft analysis using the LSA method.
12

Zvýšení výkonu přeplňovaného motoru pro Formuli Student / Performance optimisation of turbocharged engine for Formula Student

Špičák, Milan January 2015 (has links)
Diplomová práce je zaměřena na výběr pohonné jednotky pro Formuli Student, sestavení spolehlivého výpočtového modelu za využití pokročilého testování. Dále se zaměřuje na přípravu vhodných podmínek pro testování, samotné testování a následnou kalibraci řídicí jednotky pro validaci simulací a také pro efektivní a spolehlivé řízení motoru v náročných závodních podmínkách. Je zároveň součástí komplexního projektu, který se zabývá celkovým vývojem přeplňovaného jednoválcového motoru pro tým TU Brno Racing.
13

Ventilový rozvod přeplňovaného motoru formule Student / Valve Train for Turbocharged Formula Student Engine

Buchta, Martin January 2016 (has links)
This diploma thesis deals with valve train design of turbocharged engine used in Formula Student category race car. Based on thermodynamic model, a proper valve timing was chosen to achieve maximum power at high engine speed. A kinematic model was used to compute final cam profiles and CAD model was created.
14

Understanding complex CI-combustion strategies : an experimental investigation

Michailidis, Antonis D. January 2012 (has links)
Within this body of work several series of experiments will investigate the nature of complex combustion in an experimental single-cylinder engine emulating a modern passenger car size compression-ignition (CI) engine. Regimes of single, piloted single and piloted split-main injections will be tested and compared in terms of combustion characteristics, specific emission output and cyclic behaviour to determine how increased injection complexity affects the emissions and output of the modern CI engine. Through these tests, the effect of fuel-line stationary waves will be demonstrated and investigated, showing conclusively that optimised engine calibration is essential to account for injector-generated waves in any multiple injection scenario. This data will then be confirmed with a dedicated analysis using an injector rate measuring tube. The tests will then be expanded to include examination into the behaviour of injector needle-lift standard deviation over its operating cycle, in-cylinder pressure standard deviation behaviour and trends over the combustion cycle as well as IMEP variability. Through these tests a novel method to detect start of combustion will be proposed and compared to conventional methods. Low temperature combustion (LTC) will be tested under incremental injection complexity. Tests will be optimised for combustion phasing and injection pressure, with a view to analysis of emissions, output and cyclic behaviour to establish whether the knowledge gained about conventional combustion holds true under LTC. Optimization of engine parameters will be shown to result in easier to implement LTC regimes with superior emissions characteristics. Finally, LTC tests will be expanded to include 30% and 50% by volume gas-to-liquid fuel (GTL) blends in order to determine whether fuel characteristics further influence emissions, output and cyclic behaviour in LTC through complex injection regimes. How GTL-blend ratio affects trends in emissions and cyclic behaviour will also be examined and compared to conventional diesel fuel.
15

Konstrukce experimentálního jednoválcového motoru s plovoucí vložkou / Design of Experimental One-cylinder Engine with Floating Liner

Svoboda, Radovan January 2013 (has links)
The aim of this master`s thesis was to design a single-cylinder test engine for measuring of the friction forces between the piston group and the cylinder liner. Main engine parameters are based on the common production engine. A floating liner device was chosen for a friction forces measurement. It was necessary to solve an attachment and sealing of the floating liner. Stress-strain analysis of the floating liner has been done. Next step was to re-design a production crankshaft also with a connected balancing devices for single-cylinder engine. Powertrain was seated in a completely new units. Finally the engine was completed and mounted on a stand.
16

Jednoválcový motor pro silniční závodní motocykl / Single-cylinder Engine of a Road Racing Motorcycle

Morozov, Anton January 2014 (has links)
This thesis describes the design of four-stroke single-cylinder liquid-cooled engine with a displacement of 250 cm3 designed for Moto3 road racing motorcycle. The first chapter describes designs of existing modern engines and requirements to these engines. The next section describes the design of crank mechanism and its components. The following part describes balance shaft, timing mechanism, cylinder, cylinder head, crankcase, cooling system, lubrication system.
17

Jednoválcový čtyřdobý motor motokrosového motocyklu / Single-Cylinder Four-Stroke Engine of a Motocross Motorcycle

Vacula, Jan January 2015 (has links)
This diploma thesis is focused on construction of one-cylinder four stroke engine designed for motocross competition. The target was create the 3D model, which has foundation on the thermodynamic simulation. Kinematics of timing mechanism was designed in Lotus Simulation. For checking the main bearings life calculation was performed.
18

Fuel consumption measurements and fuelconditioning in high-pressure fuel systemfor single cylinder test cell / Mätning av bränsleförbrukning och konditionering av bränsle i högtrycksbränslesystem för encylinderprovcell

Aksoy, Can Aksoy January 2019 (has links)
This master thesis is part of a bigger project issued by AVL with the purpose to design a high pressure compression ignition fuel system for their single cylinder test cell at their facility in Södertälje. Typically compression-ignition fuel tests are being run within an operating pressure range of 500-2400 bar, but this system has to be able to run with pressures up to 3500 bar. The project was intended to be carried out by two participants where this master thesis covers the evaluation of how fuel consumption rates shall be measured in the system described above as well as how the fuel shall be conditioned. The selected concept for measuring fuel consumption rate was based on measuring the mass flow on the low-pressure side of the system with a Coriolis flowmeter. The chosen temperature sensor for monitoring the temperature on the high-pressure side was a K-type thermocouple which would be directly connected to the fuel rail in the system. A bleeder was selected on the basis that it had been used in one of AVL's old test cells. A heat exchanger could not be chosen. However a rough estimation of the capacity needed for a heat exchanger was calculated for future reference. The methodology used to develop a concept was based on the engineering project process taught to students at Karlstad University. First a project plan was made followed by a solution-independently expressed product specification including a specification of requirements and QFD-matrix. Several concepts were generated for measuring the fuel consumption by evaluating different measuring principles, available components, possible positions of the components within the system and combinations with different fuel supply concepts. Less extensive methods were used for the remaining tasks in the detailed engineering phase of the project. The concepts were compared using Pugh's analysis and a concept was selected in collaboration with AVL. The majority of the objectives for this master thesis could be successfully carried out. The documentation and drawings requested by the client, manufacturing of the system, implementation and validation into the test cell could not be done due to lack of time. This, along with the selection of a heat exchanger and low-pressure thermocouple was left for future work.
19

Simulation numérique d'écoulements autour de corps non profilés par des modèles de turbulence hybrides et un schéma multirate / Numerical simulation of flows around bluff bodies with hybrid models and a multirate scheme

Itam, Emmanuelle 30 November 2017 (has links)
Ce travail est une contribution à la simulation numérique d'écoulements turbulents autour de corps non profilés. Après avoir précisé les ingrédients numériques et les modèles de turbulence utilisés dans nos simulations, nous présentons une étude sur l'évaluation des effets de la procédure dynamique des modèles de sous-maille dans un modèle VMS-LES et une approche hybride RANS/VMS-LES. Des problèmes d'écoulements autour d'un cylindre seul et en tandem sont considérés. Nous étudions ensuite le comportement de modèles de turbulence hybrides pour la simulation d'écoulements en régime sous-critique autour d'un cylindre circulaire. Le calcul de l'écoulement autour d'un cylindre de section rectangulaire par l'approche VMS-LES est aussi présenté. Enfin, dans une dernière partie, après avoir fait une revue des travaux importants sur les schémas d'avancement en temps multirate, nous proposons une nouvelle approche explicite multirate par agglomération de volumes finis que nous appliquons à des calculs d'écoulements turbulents complexes en utilisant un modèle de turbulence hybride. / This work is a contribution to the numerical simulation of turbulent flows around bluff bodies. After specifying the numerical ingredients and the turbulence models used in our simulations, we present a study on the impact of the dynamic sub-grid scale modeling in VMS-LES model and a RANS/VMS-LES hybrid turbulence approach. Simulations of flows around a cylinder and a tandem are performed. Next, we assess the behaviour of some hybrid turbulence models for the simulation of flows around a circular cylinder in the subcritical regime. The computation of the flow around a rectangular cylinder with the VMS-LES approach is also presented. At last, after a review of some important works on multirate time advancing schemes, we propose a new volume-agglomeration explicit multirate approach that is applied to the computation of complex turbulent flows by a hybrid turbulence model.
20

Development Of An Advanced Methodology For Automotive IC Engine Design Optimization Using A Multi-Physics CAE Approach

Sehemby, Amardeep A Singh 09 1900 (has links) (PDF)
The internal combustion engine is synonyms with the automobile since its invention in late 19th century. The internal combustion engine today is far more advanced and efficient compared to its early predecessors. An intense competition exists today amongst the automotive OEMs in various countries and regions for stepping up sales and increasing market share. The pressure on automotive OEMs to reduce fuel consumption and emission is enormous which has lead to innovations of many variations in engine and engine-related technologies. However, IC engines are in existence for well more than a century and hence have already evolved to a highly refined state. Changes in IC engine are therefore largely incremental in nature. A deterrent towards development of an engine configuration that is significantly different from its predecessor is the phenomenal cost involved in prototyping. Thus, the only viable alternative in exploring new engine concepts and even optimizing designs currently in operation is through extensive use of CAE. In light of published work in the field of analysis of IC engines, current research effort is directed towards development of a rational methodology for arriving at a weight-optimized engine design, which simultaneously meets performance of various attributes such as thermal, durability, vehicle dynamics and NVH. This is in contrast to the current methodology adopted in industry, according to which separate teams work on aspects of engine design such as combustion, NVH (Noise, Vibration and Harshness), acoustics, dynamics, heat transfer and durability. Because of the involvement of heterogeneous product development groups, optimization of an engine for weight, which can have a significant impact on its power-to-weight ratio, becomes a slow process beset with manual interventions and compromise solutions. Thus, following the traditional approach, it is quite difficult to claim that an unambiguous weight-optimized design has been achieved. As a departure from the practiced approach, the present research effort is directed at the deployment of a single multi-physics explicit analysis solver, viz. LS-DYNA - generally known for its contact-impact analysis capabilities, for simultaneously evaluating a given engine design for heat transfer, mechanical and thermal loading, and vibration. It may be mentioned that only combustion analysis is carried out in an uncoupled manner, using proven phenomenological thermodynamic relations, to initially arrive at mechanical and thermal loading/boundary conditions for the coupled thermo-mechanical analysis. The proposed methodology can thus be termed as a semi-integrated technique and its efficacy is established with the case study of designing a single cylinder air-cooled diesel engine from scratch and its optimization.

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