|
|
Charge Efficiency of a Gasoline Turbocharged Engine
Holas, Tomáš ; Böhm, Michael (referee) ; Svída, David (advisor)
This bachelor thesis deals with the topic of volumetric efficiency of a gasoline turbocharged engine. The first part of this thesis is devoted to research on this topic. In the second part of the thesis an analysis of data from a 1.5 TSI engine from the Volkswagen group line-up obtained during the WLTP test was performed. This analysis was achieved by the means of creating regression models on the measured data and comparing their results. The result of this analysis was the determination of the main ordinarily measured parameters on which the volumetric efficiency depends.
|
|
|
Recent trends in electric drive units of passenger vehicles
Drapela, Lukáš ; Fridrichová, Kateřina (referee) ; Böhm, Michael (advisor)
Bachelor’s thesis is focused on providing a comprehensive overview of the current architecture of electric drivetrains for passenger cars with offering specific examples and their critical evaluation. The first part of the thesis aims to describe the function of several different types of electric motors. This thesis continues with a description of the architecture of hybrid vehicles followed by vehicles powered purely by electricity. The final part of the thesis is dedicated to current trends in increasing efficiency and range of electric cars. This part is then supported by a calculation of energy demand of the electric vehicle model for selected comparative parameters using the GT-Suite simulation programme.
|
|
|
Increasing the efficiency of modern internal combustion engines
Kuzmin, Aleksei ; Böhm, Michael (referee) ; Beran, Martin (advisor)
This bachelor's thesis deals with the issue of increasing the efficiency of internal combustion engines, which is of significant importance nowadays due to the popularity of personal cars. The given problem is closely related to the reduction of fuel consumption during the operation of the above-mentioned machines and the great pressure of emission standards. The global climate change of our planet and the great impact on human health caused by the amount of harmful emissions of exhaust gases, which are motivations for further research in the given area. For solving a specific issue was chosen a research method, which consists of using quality information sources and professional scientific articles. The basic procedures in the elaboration of this bachelor's thesis have the following character: a brief historical overview of the development of internal combustion engines, theory in the context of the issue and definition of the necessary quantities, comparison according to basic parameters (efficiency, principle of work, emissions, specific effective fuel consumption) of three current methods of solution (millerization, Atkinson cycle, variable compression ratio), discussion of achieved results, drawing of important conclusions. The conclusion of the thesis is the evaluation of the advantages and disadvantages of the chosen solutions to the given problem, the potential of using and the assumption of the future of internal combustion engines.
|
|
|
Thermodynamic 1-D model of the turbocharger of an internal combustion engine
Mrázková, Kristýna ; Böhm, Michael (referee) ; Štětina, Josef (advisor)
The thesis deals with 1D heat transfer simulation of turbine housing laying emphasis on temperature of exhaust gas leaving the turbine. The thesis covers construction and thermodynamics of turbochargers, SCR catalysts and 1D simulation software. Then the thesis focuses on exploring turbine housing 3D model discretization, building physical turbocharger model for 1D simulation of heat transfer through turbine housing with time dependent input values and predicting temperature of exhaust gas flowing through turbine outlet in compliance with NEDC cycle. Result analysis and a suggestion of subsequent actions follow.
|
|
|
Optimization of turbocharger operation to reduce thermal instability in the exhaust
Kraicinger, Vít ; Ušiak, Michal (referee) ; Böhm, Michael (advisor)
This diploma thesis deals with the reduction of instability of exhaust gas temperatures with the help of optimized turbocharger operation, for the operation of the catalyst in the optimal temperature range. The introduction describes the individual effects on exhaust gas temperatures and the effect of this temperature on emissions. Furthermore, the work describes the turbocharger's function and individual parts, especially the types of regulations used. The 1.5 TSI EA211-EVO drive unit from Volkswagen is selected for the simulations and the optimization itself. Furthermore, the work contains the creation of two models with different turbocharger control (WG, VNT), and their subsequent optimization to approximate the real speed characteristics and adjustment for the possibility of simulations of transient phenomena. At the end of the work, the mentioned optimization of turbocharger operation on the emission WLTP cycle and the subsequent comparison of the reduction of exhaust temperature instability is performed.
|
|
|
Spark-ignition engine concept for hybrid passenger car
Břoušek, Roman ; Böhm, Michael (referee) ; Drápal, Lubomír (advisor)
Thesis aims on calculating method of engine conception for hybrid power train usage. Aim is to describe briefly overview of common combustion engines in hybrid power trains of the passenger cars. According this overview a proposal of naturally aspirated spark ignition combustion engine by specified parameters in 1-D CFD will be made, while the effort is to take into account less complexity and production costs at the same time higher efficiency in the most load modes.
|
|
|
Conceptual design of the conversion of an electric motorcycle
Roman, David ; Zeizinger, Lukáš (referee) ; Böhm, Michael (advisor)
The work is about the study of the current offer of electric motorcycles, individual structural elements, and the concept of using an electric motor and battery. Furthermore, the work compares the operating costs of conventional internal combustion engines and electric motors. The main part of the work is the calculation of the battery capacity for the motorcycle, which is converted from a conventional internal combustion engine to an electric motor and the selection of a suitable engine and battery storage concept, so that the dynamics of the motorcycle is not significantly affected.
|
|
|
Dieselgas Engines
Březina, Tomáš ; Böhm, Michael (referee) ; Štětina, Josef (advisor)
This bachelor thesis deals with the topic of Dieselgas engines. The first part work is focused on the history and development of engines and motor fuels. The second part deals with diesel engines, a description of the engine operating cycle, fuel injection system, types of diesel fuel, engine efficiency and emissions. The following chapter provides an overview of gaseous fuels suitable for passenger and public transport. Of these fuels, the two most commonly used are further elaborated. The fourth chapter deals with the use of gaseous fuels in diesel engines, the possibility of conversion of these engines, both by conversion to petrol and without this change. The last chapter deals with the effect on consumption and emissions of dual fuel engines.
|
|
|
The concept of electric motors used in vehicles
Polnický, Vít ; Repka, Martin (referee) ; Böhm, Michael (advisor)
This bachelor’s thesis deals with the description of electric drives concepts in current vehicles. In the first part, the basic principle of the electric motor is explained, and different types of electric motors are described in detail. In the next part of the thesis, the electrified vehicles are divided into three groups according to the power share of electric motor for vehicle propulsion. The groups are further subdivided according to the powertrain arrangement in the vehicle, indicating the advantages and disadvantages of each concept. In the third part, specific vehicles from each group are presented and compared in terms of performance, range and price. Finally, the concepts are evaluated and a possible development is outlined.
|
|
|
An emission reduction systems for vehicles with gasoline engines
Filip, Josef ; Fridrichová, Kateřina (referee) ; Böhm, Michael (advisor)
This bachelor thesis deals with ways for emission reduction of passenger cars with an ignition engine. The introduction describes the principle of combustion, the methods of preparation of the ignition mixture and pollutants that arise during the combustion. In the main part of the work, the individual specific provisions for reducing emissions used in modern vehicles are analyzed in detail. Further the examples of current emission systems for several selected cars are presented. All the findings are summarized in the following chapter. In the next part, own configuration of the emission system is described in detail, which is designed with the regard to maximum efficiency in reducing emissions. The summary together with the evaluation of the current situation and the outline of the possible direction for further development in this area are in the last part of this work.
|
guest ::
