|
|
Plain Bearings for CI Tractor Engine
Petr, David ; Ramík, Pavel (referee) ; Dundálek, Radim (advisor)
This thesis deals with the hydrodynamic plain bearings tractor diesel engine. The first part is closer acquainted with the hydrodynamic bearing, its principles and materials used. The next part work deals with the multibody system adams-engine. The main part of this work is to model the crank mechanism and its storage in hydrodynamic bearings in the MBS program and the subsequent simulation under different operating conditions.
|
|
|
Eccentricity and broken rotor bars of induction motor
Magic, Matej ; Janda, Marcel (referee) ; Vítek, Ondřej (advisor)
Thesis presents the possibilities of diagnostics of induction motor using vibration measurements. Basis of the work is monitoring of vibration changes in case of eccentricity and interruption of rotor bars in induction motor. One part of the thesis is the measurement and processing of measured data from damaged motors. The result should be comparison between processed data, reference induction machine and computer simulation of motor.
|
|
|
Vibrodiagnostics of electrical machines
Boháček, Daniel ; Vítek, Ondřej (referee) ; Janda, Marcel (advisor)
This thesis deals with methods of vibration analysis in electric rotating machines. From the beginning, it is necessary to explain the basic concepts and introduce the issue of vibration. Next time, the work is focused on sources of vibration in electrical machines. Defects on electric rotating machines causing vibrations are described. Sensing is performed using sensors of deflection, speed and acceleration. The measured signal needs to be adjusted and filters, approximations and sampling will cover this in the next chapter. The main objective is the methods of analysis, which include the best known in the field of frequency analysis (FFT) and the envelope method in the time domain. This includes other methods such as Kurtosis factor, Crest factor, etc. There is also a basic block diagram for measuring vibrations. This block diagram is programmed and has a graphical user interface. The last part is an evaluation of the measured data of the engines.
|
|
|
Static analysis of steel footbridge
Mareková, Adela ; Martinásek, Josef (referee) ; Vlk, Zbyněk (advisor)
The subject of the bachelor thesis is static analysis of a steel footbridge. Two different models of this structure are created in RFEM 5.16 software. The first model consists only of the upper part of the structure, the second model includes also the bottom part – columns. The load is calculated manually and applied on both models in the same way. RFEM software was also used for performing the calculation. The results from models are compared between each other and ultimate limit state assessment is carried out.
|
|
|
Design of lathe chuck with machine-adjustable excentricity
Petrych, Jan ; Holub, Michal (referee) ; Tůma, Jiří (advisor)
This master´s thesis focuses on constructional design of chuck with settable eccentricity in two axes. The first part consists of brief analysis of the clamping of CNC machines and summary of available chucks with settable eccentricity. Next part deals with study of possible construction designs. Two construction variants will be based on those designs in the next part. Following part then describes dimensionality of the main parts of the chuck. Based on the calculations, the 3D model of chosen variant is created with the description of its functionality. Finally the conditions of operation for the chuck are described.
|
|
| |
|
|
Termální vývoj Saturnova měsíce Enceladu
Kozoň, Marek ; Čadek, Ondřej (advisor) ; Běhounková, Marie (referee)
We study thermal evolution of Enceladus on very long time scales. In order to do so, we created a Fortran program modeling tidal deformation and thus induced heat dissipation as well as conductive transport of the heat in the body of the moon. Effect of long-lived radioactive isotopes decay in the core on the heat generation is included. We show the dependence of a thermal scenario character on different minimal viscosity and constant eccentricity values and study chosen cases in detail. We further demonstrate that, if orbital eccentricity evolution is incorporated, its initial value has no essential effect on the thermal evolution result, with the body always freezing quickly. Lastly, we examine the dependence of a thermal scenario on added values of hydrothermal heating power from the core and present that a power magnitude can be found, with which the satellite does not freeze, nor overheats in the first 4 billions of years what is necessary for maintaining a thermal activity on Enceladus since its formation to the present time. 1
|
|
|
Methods of analysis of vibration signals
Sivera, David ; Hájek, Vítězslav (referee) ; Janda, Marcel (advisor)
The aim of the thesis is to focus on the different methods of analysis of vibration signals. Focusing on the physical fundamentals of vibrations and a description of their origin in an electrical machine. Describe the vibration sources from mechanical across the electromagnetic to the aerodynamic. Defining the current defects of electric machines and sensors suitable for the measurement of vibrations in an electric machines. Introduction to the methods of analysis of vibration signals in the time and frequency domain. Then using some of these methods for the analysis of vibration signals measured asynchronous motors with different manufacturer defined production defect. The conclusion is composed from the comparison between measured and analyzed results.
|
|
| |
|
|
Eccentricity and broken rotor bars of induction motor
Magic, Matej ; Janda, Marcel (referee) ; Vítek, Ondřej (advisor)
Thesis presents the possibilities of diagnostics of induction motor using vibration measurements. Basis of the work is monitoring of vibration changes in case of eccentricity and interruption of rotor bars in induction motor. One part of the thesis is the measurement and processing of measured data from damaged motors. The result should be comparison between processed data, reference induction machine and computer simulation of motor.
|
guest ::
