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Complex Analysis of Modal Properties of Rotating Electrical Machines
Donát, Martin ; Vlach, Radek (referee) ; Žiaran,, Stanislav (referee) ; Dušek, Daniel (advisor)
This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.
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Complex analysis of modal properties of rotating electrical machines
Donát, Martin ; Dušek, Daniel (advisor)
This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.
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Optimization of Machining Parameters Abradable Sprayed used in the Aerospace Industry
Krajkovič, Pavel ; Osička, Karel (referee) ; Kalivoda, Milan (advisor)
This thesis is focused on machining of thermal spray coatings. Particularly on testing of machining parameters and their influence on different types of abradable coatings used in the aerospace industry. The aim of research work is to test the parameters, measure cutting forces by using a dynamometer and their impact on the quality of the machined surface. Determination of the optimal machining parameters for different types of coatings based on results of measurements and the evaluation of surface quality. There are also presented techniques of thermal spray application and methods of coating evaluation. Further it describes a method of measuring cutting forces by using the dynamometer and methods of surface quality evaluation.
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Modern cutting finishing methods of outer surfaces
Laňka, Lubomír ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
This master`s thesis is focused on modern cutting finishing methods of outer surfaces. In the first part the cutting finishing technologies of outer surfaces are analysed, which is followed by a description of modern finishing methods from the fine machining up-to the nano-machining. The experimental part includes the analysis of surface roughness during front turning of a dural disc and the study of magnitudes of forces during its longitudinal turning. The thesis contains technological-economic evaluation of the achieved results.
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Residential building in Zlin
Jelínek, Roman ; Sedlák, Radek (referee) ; Benešová, Romana (advisor)
The aim of this thesis is to elaborate project documentation for new construction of low-energy residential building with 16 luxury apartments, apartment without barriers and with pharmacy of basic type. It is a four-storey detached building without basement, with flat roof, roof terraces and with balconies. Residential building is located in one of the most enjoyable parts of the city of Zlín – Jižní Svahy II in the vicinity of Central park with bicycle path and with beautiful view of the Zlín. The building will be located on land plot No. 2144/46, where is still situated unfinished building "Torso" from the late 80 years. The residential building is designed in brick system Heluz, ceiling construction is made up of prestressed hollow core slabs, perimeter walls are with external thermal insulation composite system and external doors and windows are made of plastic and aluminum with triple glazing. For heating and water heating will be utilized renewables energy, such as heat pump and solar collectors. Residential units with three residential rooms are designed with a forced ventilation by means of ventilation units with heat recovery. The building also uses modern shielding elements such as outdoor blinds and horizontal sun breakers. The part of the project are also disposition studies, seminar work and energy part.
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Measurement of velocity and frequency in synthetic jet
Flídr, E. ; Šafařík, P. ; Trávníček, Zdeněk ; Broučková, Z.
The aim of this paper is to evaluate resonance frequency of pulsation in synthetic jets of air. Resonance frequency was determined by theoretical calculation. This frequency was compared with experimental results. To obtain frequency characteristics three experimental methods were used. Velocity was measured by Pitot tube and hot wire anemometry in CTA regime. Last method was based on calculation of reaction force from relative weight changes.
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Piston for SI CNG 140 kW Engine
Hrouzek, Jan ; Drápal, Lubomír (referee) ; Svída, David (advisor)
This master’s thesis deals with the piston for modified engine 1.4 TSI from Volkswagen concern. It includes calculation of kinematics and forces reactions of the crank mechanism of the engine for speed 6071 rpm elaborated in the program Mathcad Prime. Further the work includes calculation for reducing the magnitude of lateral force and design of several variants of the piston. For the proposed design variants of the piston are performed FEM analysis of mechanical state of stress and comparisons of contact pressures in the program ANSYS Workbench.
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