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Steam turbine
Čípek, Petr ; Škorpík, Jiří (referee) ; Fiedler, Jan (advisor)
The aim of the thesis is to design a high-speed steam turbine as a small energy source. Steam turbine consists of a high-pressure, a medium-pressure and a low-pressure part with a removable condensing module. High-pressure part is designed to perform a single-stage radial turbine with axial steam outlet. The work also includes the layout of the modules and sections. To design individual parts are used steam table „X-steam“.
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Design of high-speed induction motor
Svoreň, Jan ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This work deal with troubleshooting of problem parts of high-speed induction machines. Introduction is about conception of induction machines with reference to construction specialities due to high rpm and because machines are fed by inverter. Next part is focused to design problems. A classical induction machine was measured to determination change of various losses in classic and high-speed induction machines. The computation of laboratory sample high-speed motor was specified for calculation of effective resistance and leakage reactance of solid-steel rotor with copper layer. The results of numerical calculation were validated by using finite elements method and machine design was adjusted for improving operation characteristic.
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Design of a High-speed Solid-rotor Asynchronous Generator for an Expansion Turbine
Pribulla, D. ; Vítek, O.
In this paper, an electromagnetic design of a slitted solid-rotor high-speed generator is presented. Recommendations for an analytical preliminary design were summarized. The design was further optimized using 2-D finite element method. The power of the machine is 6.15 kW at 150 000 rpm and 2% slip. An efficiency of 90% was reached, despite of high eddy losses in the machine rotor. Our design may prove to be a cost-effective alternative to the permanent magnet synchronous machine in the cryogenics application after the thermal and mechanical analysis.
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Optimization of Machining Technologies for Special Applications
Ohnišťová, Petra ; Maňková, Ildikó (referee) ; Neslušan, Miroslav (referee) ; Píška, Miroslav (advisor)
This thesis is focused on the optimization of the milling technologies for special applications with respect to the required fatigue properties of aircraft components. The theoretical part of the thesis describes in detail the key features of the high-speed and high-feed milling, surface integrity after milling and fatigue characteristics of the studied component. The key aim of the work is devoted to the analysis of the influence of the cutting conditions of the high-speed peripheral and high-feed face milling of the bottom wing panel from aluminium alloy 7475-T7351 on the surface integrity in relation to the final fatigue properties. Therefore, the part of the work is a study of metallographic structure of the material, measurement of the accompanying machining phenomenon and quantities, advanced analysis of the surface integrity (amplitude characteristics, S-N parameters), manufacturing of the highly accurate fatigue samples and fatigue testing. Furthermore, the development of sample damage during in situ tensile loading and the development of sample damage during cyclic in situ fatigue tensile loading is also studied. The achieved results and fractography of fracture surfaces show that the studied cutting conditions have a significant effect on the quality of machining and resistance to mechanical stress, but they are not a decisive factor in terms of the fatigue crack nucleation. The effect of the achieved topography for the studied cutting conditions is suppressed by the presence of large intermetallic inclusions (Al7Cu2Fe; Al-Cr-Fe-Cu-Si) with a size from 2 µm to 20 µm, being the origin on the fatigue crack nucleation.
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Design Of A High-Speed Generator For A Helium Expansion Turbine
Pribulla, Daniel
This paper presents design of an ultra-high-speed generator, propelled by a helium expansionturbine. The power output of the presented generator is 5 kW at 160 000 rpm. Very highefficiency, over 95%, was achieved thanks to the use of permanent magnet synchronous machine typeand proper material selection. Special care was taken during design of the machine rotor to meet bothmechanical and electromagnetic requirements. Only high-strength materials can withstand the load.Stator sheets have to be very thin, to suppress the skin effect and eddy current losses, especially withthe 4 pole configuration. It was shown that the design process for standard, low-speed machines canbe used with the awareness of it’s limitations. Weak points of the design, which should be furtherinvestigated, were pointed out.
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Design Example Of Radial Active Magnetic Bearing For High-Speed Machine
Rura, David
Development of high-speed electrical machines reopened a door for further development in a field of magnetic bearing. Conventional ball bearings reached their limits and can’t bear such as high-speed in many modern turbo applications. Another way is to use air bearing which perform lower load capacity and stiffness. Hence, magnetic bearing seemed to be an advantageous solution in many application. The main cons of active magnetic bearing (AMB) are its space requirement and in case of active bearing also power amplifier and controller. In this paper the design of radial AMB for a motor 12 kW, 45000 rpm is calculated. Typically, analytical solution excludes side phenomenons and thus analytically modelled radial AMB is optimized numerically. This paper provides a full design of AMB including design geometry and performance properties.
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Finite Element Analysis of High Speed Induction Motor With Axially Slitted Rotor
Klíma, Jiří
This paper deals with an analysis of three phase, two pole high speed induction machine with axially slitted solid rotor. The finite element model of induction motor with axial slits has been developed and motor has been analyzed for several slips in order to get performance characteristics. Setting the simulation is crucial and will be discussed. All-important fields and performance characteristics are presented.
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Steam turbine
Čípek, Petr ; Škorpík, Jiří (referee) ; Fiedler, Jan (advisor)
The aim of the thesis is to design a high-speed steam turbine as a small energy source. Steam turbine consists of a high-pressure, a medium-pressure and a low-pressure part with a removable condensing module. High-pressure part is designed to perform a single-stage radial turbine with axial steam outlet. The work also includes the layout of the modules and sections. To design individual parts are used steam table „X-steam“.
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Design of high-speed induction motor
Svoreň, Jan ; Ondrůšek, Čestmír (referee) ; Vítek, Ondřej (advisor)
This work deal with troubleshooting of problem parts of high-speed induction machines. Introduction is about conception of induction machines with reference to construction specialities due to high rpm and because machines are fed by inverter. Next part is focused to design problems. A classical induction machine was measured to determination change of various losses in classic and high-speed induction machines. The computation of laboratory sample high-speed motor was specified for calculation of effective resistance and leakage reactance of solid-steel rotor with copper layer. The results of numerical calculation were validated by using finite elements method and machine design was adjusted for improving operation characteristic.
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Analysis of the availability of broadband in a particular location
Burian, Petr ; Toman, Prokop (advisor) ; Pavlíček, Antonín (referee)
The aim of this thesis is to analyze the availability of broadband internet in the small village Vysoký Újezd in the Central Region. The first part describes theoretically different technologies that offer broadband Internet access and are available in the Czech Republic. The second part contains all offer nationwide and regional providers of broadband, offering services in the area of the selected municipalities. The most used technologies in the village are Wi-Fi and ADSL, conversely via cable TV or fiber optic networks in the municipality are not available. Work can help the inhabitants of Vysoký Újezd select appropriate high-speed Internet connection. The last part contains its own survey among the inhabitants of the village, focusing on their Internet connection. The answers are presented in graphs, commented and evaluated.
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