|
|
Rotary Piston Engine for Small Mobile Systems
Drbal, Milan ; Puškár, Michal (referee) ; Žák,, Marek (referee) ; Píštěk, Václav (advisor)
The dissertation deals with the issue of 1D modelling of a rotary piston engine and prediction of engine characteristics for use in its further development. In this work, the 1D mathematical model of the engine is validated by measuring the combustion pressure in the work chamber, in the intake section and further in the exhaust channel. These data are used to determine the coefficients of the combustion model and, above all, the combustion chamber leakage model. Both effects cannot be modelled accurately included without measuring the work chamber pressures. The use of 1D mathematical simulations is well described in the literature for a reciprocating engine. However, their use for a rotary piston engine is more complicated from the point of view of the geometric differences of both types of engines. In this work, a suitable method of modelling rotary piston engines and their verification using technical experiments and CFD simulations will be described.
|
|
|
Neural networks used in autonomous vehicles
Ryšavý, Jan ; Píštěk, Václav (referee) ; Kučera, Pavel (advisor)
This bachelor thesis deals with the use of neural networks in autonomous vehicles. The first part of the thesis presents the basic principles of neural networks and learning methods that are used in autonomous vehicles. Then the thesis describes the architecture and functions of neural networks. The second part of the thesis also describes the different types of autonomous vehicles, their classifications and an overview of the sensors used by autonomous vehicles. The last part of the thesis deals with the implementation of neural networks in ECUs using programming languages and libraries, and applications such as object detection and marker recognition.
|
|
|
Operation of electric vehicles, hybrid vehicles and vehicles with an internal combustion engine
Herzog, Radim ; Píštěk, Václav (referee) ; Kučera, Ondřej (advisor)
This bachelor's thesis deals with the comparison of different propulsion concepts and their consumption, efficiency, and amount of emissions produced during operation. Although electric vehicles do not produce any local emissions, it is necessary to consider that emissions are generated during the production of electricity in power plants. The main part of the thesis introduces the functional principles of individual propulsion systems. Furthermore, it describes the formation of exhaust gas emissions in combustion engines and outlines their limits. Subsequently, the amount of emissions produced by a power plant for the operation of a specific example of an electric vehicle and a hybrid vehicle is calculated. Finally, a comparison of emissions production from representative examples of each propulsion system is illustrated.
|
|
|
Analysis of the crank mechanism of a two-stroke engine
Matyáš, David ; Píštěk, Václav (referee) ; Svída, David (advisor)
This diploma thesis is a comparison of two versions of the crank mechanism of the Jawa 350 two-stroke engine. The diploma thesis if prefaced by researching the design solutions of multi-cylinder two-stroke engines with examples of their use. The following is a description of the theoretical properties of the two examined crank mechanisms in terms of inertial effects. For both engine concepts, the engine performance characteristics is measured and compared to each other. The engine with modified crankshaft is subjected to a pressure indication, which serves as one of the inputs to the strength analysis of the crankshaft. This is done by a combination of MBS simulation, FEM analysis and calculation of fatigue safety factor by LSA analytic method.
|
|
|
Spark ignition engine with variable compression ratio
Fűri, Peter ; Píštěk, Václav (referee) ; Kaplan, Zdeněk (advisor)
With the aim of reducing pollutant emissions from internal combustion engines, the application of stoichiometrically operated spark ignition engines, for light vehicles, has been overcoming the compression ignition engines market share throughout the past years. The ability of a substantial reduction of the primary harmful emissions (HC, CO, and NOx). Nonetheless, with increasing attention to CO2 emissions, the development of highly efficient downsized spark ignition engines turns to be of enormous interest. However, to enable high load operation on such downsized engines, the compression ratio must be reduced due to knock limitations, reducing the partial-load operations efficiency. The work tries to describe solutions that have already been developed by various car manufacturers and to describe in detail my proposed design solution for changing the compression ratio using two-stage system.
|
|
|
Application of cooled Exhaust Gas Recirculation on modern gasoline engines
Bazala, Jiří ; Bauer, František (referee) ; Tůma, Jiří (referee) ; Píštěk, Václav (advisor)
This document describes the possibilities of increasing the efficiency of an internal combustion engine using cooled EGR (exhaust recirculation system), water injection and their combination. To investigate it the engine model was calibrated based on the experiment. It was investigated the effect of the externally cooled EGR system on key engine parameters such as efficiency, specific fuel consumption, performance and others on this model. Here it was concluded that EGR system has unsatisfactory parameters in terms of the ratio of achieved results and complexity. Therefore, the water injection model was tested on the model and compared with the EGR system. The engine model with water injection was evaluated as more advantageous. Therefore, it was decided to invest available sources to the experimental vehicle with water injection and verify experimental results with model. Using of both systems, the EGR system and water injection, and ideally with the possibility of pre-ignition, appears to be the most suitable combination with regard to the observed parameters.
|
|
|
European emission legislation
Rytina, Matěj ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
The aim of this bachelor thesis was to write about exhaust emissions and their influence on environment, briefly sum issue of emission standards up and mainly sum existing facts about the “Dieselgate” affair up. I wanted to objectively evaluate this issue in my bachelor thesis. Asset of this thesis was mend to be in fact that this affair has not been academically covered yet.
|
|
|
Development of transaxles in automobiles
Kubiš, Vojtěch ; Kaplan, Zdeněk (referee) ; Píštěk, Václav (advisor)
This bachelor thesis is concerned of development of transaxles in automobiles. Overview of types of axles is mentioned here as well as their working principles. Attention is also given to suspension and damping with description of how it works. In this thesis are described solutions of selected cars suspensions.
|
|
|
Development and weight reduction of central housing for commercial vehicles
Blecha, Martin ; Pittl, Michal (referee) ; Píštěk, Václav (advisor)
The theoretical part of the thesis is focused on the clarification of the central housing function and its placement in a truck. The central housing function and placement depend on a vehicle chassis design. There is the weight optimization of the housing which is solved in the practical part of the thesis. The optimization is based on strength calculations of the Finite Element Method. There are weight savings and financial savings evaluated at the end of the thesis.
|
|
|
Design of Car Initiator
Suchý, Jan ; Píštěk, Václav (referee) ; Novotný, Pavel (advisor)
The bachelor thesis is focused on proposal solution of automotive initiator construction and design. The proposal is being carried out with regard to the need to ensure the maximum functionality of the whole element. As for the choice of materials and used technology the costs and procedures commonly used today are not being taken into account. The main objective is to eliminate the shortcomings of current automotive initiators and the proposal of technological procedures in the production of a new component.
|
guest ::
