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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
641

Strukturální analýza bloku motoru / Structural Analysis of an Engine Block Design

Chevtaikin, Sergei January 2019 (has links)
This master thesis focuses on structural analysis of combustion engine block. The main goal of this work was the design and compare individual solutions of long and short engine’s blocks. First part of work shows existing engine block designs and solutions. Based on the research part, the CAD design of the engine blocks and their discretization was performed by pre-processor programs. Structural analysis and their final comparison were provided by FEM and MBS programs.
642

Návrh snížení počtu svarů u rámových dveří kolejových vozidel z Al slitin / Proposal of welds number reduction on aluminium aloys frame doors for rail vehicles

Šplíchal, Jan January 2019 (has links)
This Diploma thesis presents possible proposals of welds number reduction frame doors for rail vehicles welded from profiles from aluminium alloy EN AW 6060, which is heat treated by temper T66. Profiles are welded by TIG process with additional material S Al 5087 (AlMg4,5MnZr). The heat treatment by the welding cycle causes a change in structure of basic material and decrease of mechanical properties due to dissolution of precipitates. To measure the necessary mechanical properties of the material after welding a tensile test was performed on the delivered samples. The resulting values from tensile test were subsequently used as cut – off values in the new door frame design by FEM simulation in Virtual Performance Solution software with PAM – Crash extension. The newly designed frame was welded according to the necessary welding procedure specifications, which are also part of the thesis. The conclusion is devoted to the economic evaluation of the current and new design of the door frame.
643

Konstrukční návrh manipulačního zařízení ve výrobě pneumatik / Design of Tyre Production Line Manipulation Equipment

Solař, Adam January 2019 (has links)
The subject of this diploma thesis is to design a new construction of the machinery, which is used for manipulation with tire carts in rubber industry. The reason for the new design is to eliminate the main shortcomings of the existing provision. The aim of this project was to elaborate an overview of the current designs of the handling equipment in question and to subsequently construct a new suitable design solution. In addition, several conceptual calculations were needed to be used in the selection of the appropriate electric motor, transmission, pneumatic cylinders and wiring. The relevant parts were designed using structural FEM analyses. The several variants of the solutions were considered for a suitable construction design. Based on these FEM simulations, the relevant parts have been modified in terms of geometry so that the resulting manipulating machinery meets all the criteria, especially regarding safety.
644

Topologická optimalizace pohyblivé, pevné a základní desky elektromechanického vstřikolisu / Topology optimization of movable, fixed and based plate of electromechanical injection-moulding machine

Kecík, Samuel January 2019 (has links)
The master thesis deals with the design of geometry of plates of the injection molding unit using the FEM tool Topological Optimization. The reason for this is to reduce the weight of these components, which is beneficial in the transport and assembly of the injection molding machine. However, the final models of geometry of plates must meet certain requirements in terms of the limit state of deformation, the limit state to the critical value of the equivalent stress. This condition involves both limit state of elasticity and limit state of fatigue. Computational modeling and also Topological Optimization are performed in ANSYS Workbench.
645

Výpočtové posouzení přírubových spojů / Analytical calculations of flange joints

Polišenská, Anna January 2019 (has links)
This Master’s thesis deals with flange joints. A suitably designed flange joint (FJ) construction and installation is necessary to ensure the reliability of piping systems and machinery where these joints are used. The thesis describes the procedures of their design and assessment in terms of tightness, strength and durability. It focuses on the stiffness calculation of all components of FJ – primarily the stiffness of flanges, bolts and seals. The main part of the work was to create a computational program by using the Python language to determine the appropriate preload force in the bolts. The program uses the procedures described in the ČSN EN 1591-1 standard. The thesis describes computational algorithms of this program, verification of the program and its use in the assessment of FJ on a specific technical work – pressure vessel with adjacent piping. Verification was performed by comparing the acting force to the seals obtained from the computational program and the stress-strain analysis using the finite element method (FEM), where the load model in this stress-strain analysis included the preload force obtained from the computational program. The application of the pressure vessel computational program consisted in determining the preload forces for all FJs of this assembly. The last part describes the assessment of the most loaded FJ. Again, stress-strain state was evaluated using FEM and FJ was assessed for tightness, strength and durability using the NTD A.S.I. standard.
646

Návrh vysokootáčkového elektrického stroje. / Design of a high-speed electrical machine.

Šolc, Martin January 2019 (has links)
This diploma thesis is dedicated to design of highspeed induction motor with power 30 kW, 60 000 rpm. In the beginning of the thesis basic problematic of highspeed motors, used materials and motor types is discussed. The practical part of the thesis concerns design of the motor itself, creating a model in ANSYS Maxwell software, performing several simulations and optimalization of the designed machine. In the last parf of this thesis each simulation is evaluated and the final model of the machine is introduced.
647

Návrh magnetického ložiska pro elektrický stroj / Design of a Magnetic Bearing for an Electrical Machine

Rúra, Dávid January 2019 (has links)
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.
648

Simulační a experimentální analýza řezání kotoučovou pilou / Simulative und experimentelle Analyse des Kreissägens

Helienek, Matúš January 2018 (has links)
This thesis deals with analysis of dynamic forces and vibrations created during cutting with saw. The analysis is done on both simulation and experimental level. Acquired signals are evaluated with signal tools as STFT, CWT and DWT.
649

Šestiválcový řadový vznětový motor s vypínáním válců / Six-cylinder in-line diesel engine with cylinder deactivation

Novosád, Ivan January 2020 (has links)
Master 's thesis deals with design of a drivetrain of six cylinder inline engine with cylinder deactivation for heavy agricultural vehicles. In this thesis were devised various possibilities of crankshaft balancing, the best design solution of counterweight was based on optimization in software Catia. Further, the crankshaft was analysed for force and momentum loading and torsional vibration, based on which, the torsional vibration damper was designed. There were considered several options for cylinder deactivation, which were analysed for finest run of engine and the best thermal distribution. Based on these criteria, the best option was to deactivate 2nd and 5th cylinder. The crankshaft was analysed for the fatigue failure by finite element method. The fatigue failure is the most dangerous case for the crankshaft, the resulting safety factor for this limit state is 3,05.
650

Návrh závodního vozidla kategorie R1 / Design of R1-Class Racing Car

Bureš, David January 2020 (has links)
The goal of this thesis is to create a conceptual design of a rally car in Ra5 (former R1) category. The thesis contains interpretation of regulations, overview of former cars in this category and requirements for such vehicle. The thesis describes choice of vehicle and description of modifications, including specific components. The thesis also describes construction of several designs of rollcage, which were mutually compared, and their homologation tests. The thesis also determines small series price of such vehicle.

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