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Design of Turbocharger Bearing for Low Viscosity Oils
Plánka, Jakub ; Dlugoš, Jozef (referee) ; Novotný, Pavel (advisor)
The first part of the thesis describes journal bearings characteristics, their function and lubrication. The second part of the thesis is about a rotor-dynamics issue and how to use numerical and experimental methods for verification of a new bearing design. The practical part of the thesis is focused on analyse a current design of bearings in MBS. In the last part has been made and verified a new bearing design.
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Design of a Magnetic Bearing for an Electrical Machine
Rúra, Dávid ; Vítek, Ondřej (referee) ; Bárta, Jan (advisor)
The current development in the field of electric machinery is focusing on high-speed electric machines. This opens also other fields related to high-speed machines. One of them are magnetic bearing systems. Tradition approach of using ball bearing brings a few problems in design dealing with friction at high speeds. Together with magnetic bearings, development is their control. Faster chips opened a new way of thinking of control and helped to evolve robust control loops. The biggest advantage of magnetic bearing is non-friction run and almost no maintenance. Compare to traditional ball bearing, a magnetic bearing system needs more space and in some applications could happen that the shaft will be twice as long. This problem can be solved designing complex system with motor and integrated magnetic bearing what leads to downsizing. In this master thesis, the design of magnetic bearing for 12kw, 45000rpm is discussed. It focuses on practical design and correlations between parameter selection. The analytical approach is used to sketch the design and optimization is done afterwards. Problem with an analytical design is that it doesn't cover all parasitic phenomenae and thus numerical modelling snd optimization are demanded. Also, the critical speed analyze is included in this thesis. The results of the work will be used for manufacturing prototype as an extension to the existing high-speed machine.
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Seismic Analysis of The Pump 200-QHD
Čapičík, Martin ; Chlud, Michal (referee) ; Lošák, Petr (advisor)
The main goal of this thesis is dynamic analysis of shaft of booster pump QHD-200. In the beginning we offer basic equations generally used in dynamics and common/possible methods for their solution. Then we focus on specific problems connected with rotor dynamics and using simple Laval rotor we show their mathematical interpretation. Based on given load as accelerogram we create response spectrum in different ways (using different methods) and compare their CPU time demand. In the next part we make three finite element models of different physical level. We perform modal analysis and comparison of eigen frequencies, mode shapes. In following chapter transient analysis was performed on all models. As load we use accelerogram. We evaluate translations in particular positions of model. After that, we decide whether or not gap between impeller and stator case will be erased. Finally we make assessment of force acting upon bearings.
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Design of a Magnetic Bearing for an Electrical Machine
Rúra, Dávid ; Vítek, Ondřej (referee) ; Bárta, Jan (advisor)
The current development in the field of electric machinery is focusing on high-speed electric machines. This opens also other fields related to high-speed machines. One of them are magnetic bearing systems. Tradition approach of using ball bearing brings a few problems in design dealing with friction at high speeds. Together with magnetic bearings, development is their control. Faster chips opened a new way of thinking of control and helped to evolve robust control loops. The biggest advantage of magnetic bearing is non-friction run and almost no maintenance. Compare to traditional ball bearing, a magnetic bearing system needs more space and in some applications could happen that the shaft will be twice as long. This problem can be solved designing complex system with motor and integrated magnetic bearing what leads to downsizing. In this master thesis, the design of magnetic bearing for 12kw, 45000rpm is discussed. It focuses on practical design and correlations between parameter selection. The analytical approach is used to sketch the design and optimization is done afterwards. Problem with an analytical design is that it doesn't cover all parasitic phenomenae and thus numerical modelling snd optimization are demanded. Also, the critical speed analyze is included in this thesis. The results of the work will be used for manufacturing prototype as an extension to the existing high-speed machine.
|
|
|
Design of Turbocharger Bearing for Low Viscosity Oils
Plánka, Jakub ; Dlugoš, Jozef (referee) ; Novotný, Pavel (advisor)
The first part of the thesis describes journal bearings characteristics, their function and lubrication. The second part of the thesis is about a rotor-dynamics issue and how to use numerical and experimental methods for verification of a new bearing design. The practical part of the thesis is focused on analyse a current design of bearings in MBS. In the last part has been made and verified a new bearing design.
|
|
|
Seismic Analysis of The Pump 200-QHD
Čapičík, Martin ; Chlud, Michal (referee) ; Lošák, Petr (advisor)
The main goal of this thesis is dynamic analysis of shaft of booster pump QHD-200. In the beginning we offer basic equations generally used in dynamics and common/possible methods for their solution. Then we focus on specific problems connected with rotor dynamics and using simple Laval rotor we show their mathematical interpretation. Based on given load as accelerogram we create response spectrum in different ways (using different methods) and compare their CPU time demand. In the next part we make three finite element models of different physical level. We perform modal analysis and comparison of eigen frequencies, mode shapes. In following chapter transient analysis was performed on all models. As load we use accelerogram. We evaluate translations in particular positions of model. After that, we decide whether or not gap between impeller and stator case will be erased. Finally we make assessment of force acting upon bearings.
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Pohyb rotoru uloženého v aerodynamických ložiskách
Půst, Ladislav ; Šimek, J. ; Kozánek, Jan
The tilting pad bearings are very often applied in high speed rotating machines. The exact solution of bearing characteristics, including the motion of tilting pads, is very difficult and not yet completely elaborated. an approximate method for calculattion of rigid rotor motion with large amplitudes limited only by the bearing clearance is presented. The models of stiffness and damping forces valid for the entire area of journal motion in the aerodynamic bearingś clearance are based on the transformation of linear stiffness and damping characteristics calculated for two cases of stationary state and extended to the whole bearing field by using the correction function fc(r). Differential equations of motion of rigid rotor supported on two aerodynamic bearings with proposed nonlinear characteristics are numerically solved and resulting time histories of journal motion, their plane trajectories will be presented.
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Účinek motoru s omezeným výkonem na kmitání systému s blízkými rezonancemi
Půst, Ladislav
The paper discusses dynamic behaviour of two degrees of freedom system excited by centrifugal force of unbalance. electric motor with limited power drives the rotor with unbalance. This "weak" property of energy source strongly influences the responses of vibrating system, especially if its eigenfrequencies are close each other. This is often case in technical praxis, mainly in rotating machinery, where the stiffness anisotropy of rotors supports leads to interesting dynamic phenomena. Particular attention is given also to the internal dynamic interaction of mechanical part of electric motor with the processes in the electromagnetic part at the non-stationary vibrations.
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