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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.
131

Dvoudobý motor pro malou mechanizaci / 2-stroke Engine for Small Mechanization

Böhm, Milan January 2008 (has links)
This diploma thesis includes progress constructional design of 2 - stroke engine for small mechanization, using modern tools of computer aided design. In the first part is mentioned short summary contemporary types small mechanization with 2 - stroke engines. Follows part devoted conceptual design with calculation of the main dimensions of engine cylinder. After assesment strength load of cranked mechanism, is effected stress analysis of connection rod, whose design and modeling is part of work, how by the help of analytical figures from appropriate literature so by final element method. Last part of those work is estimation results with presentation parameters, which affect power of 2 - stroke engines for small mechanization.
132

Dvoudobý motor pro malý motocykl / 2-stroke Engine for Small Motorcycle

Hlaváč, Štěpán January 2008 (has links)
This diploma thesis contains an engineering design of a two-stroke engine for small motorcycle. In the first part, the background research of these motors was made. Main dimensions of the engine and a calculation of the forces acting in crank mechanism were determined. Further check stress analysis of connection rod and calculation using a finite element method were performed. This diploma thesis also includes virtual 3D models of all designed parts and a drawing of cross section of the motor.
133

Aplikace modelů tvárného porušování při výpočtové simulaci technologických operací / Application of ductile fracture models in computational simulation of manufacturing operations

Hůlka, Jiří January 2008 (has links)
This diploma thesis is an introduction to the ductile fracture under large plastic deformations and is focused to numerical simulation of this type of problems. Explicit finite element method (FEM) is discussed in theoretical introduction as the most powerful tool for numerical calculations in this area. Actual state of research and possibilities of ductile fracture simulations are presented. Applicable fracture criteria are collected in a summary sheet and the most important ones are selected and commented in detail. The problem of implementation of selected criteria into commercial FEM packages is discussed, too. Main part of the work is presented in chapters 7÷9 where two ductile fracture criteria (Equivalent Fracture Strain and Johnson-Cook) are applied to numerical simulation of material cutting. All results were obtained with ABAQUS/Explicit 6.5.1 and their verification was realized by experimental measurement.
134

Návrh jednoválcového zážehového motoru / Design of Single Cylinder 4-stroke SI Engine

Číž, Petr January 2008 (has links)
Thesis deals with design of the experimental single-cylinder spark ignition engines for research purposes. The main purpose of this work is the design crankcase. Summary of possible constructions of spark ignition engines is included. Basic dimensions and 3-D design of the experimental engine resulted from the summary. The numerical analysis of proposed crankcase in ADAMS (MBS) and ANSYS (FEM) software environment is also part of the work. Generally, the proposed solution of the experimental engine was focused on the universality and simplicity of the design.
135

Čtyřdobý motor pro malou mechanizaci / 4-stroke Engine for Small Mechanization

Kuchař, Patrik January 2008 (has links)
The diploma thesis deals with a proposal of the four - stroke gas engine. There are mentioned the basic draft calculations of a crank mechanism and overhead valves. Further deals with a strenght calculation of the engine piston and analysis state of stress of the engine piston by the help of Finite Element Metod.
136

Výpočtová analýza namáhání povrchových vrstev pracovního válce při válcování za tepla / Computational analysis of working roll surface layers in hot rolling

Luks, Tomáš January 2009 (has links)
This thesis is dealing with an analysis of thermal and mechanical loads on a work-roll. First, hot rolling focused on work-roll is described in general. A theoretical analysis of roll loads and the mechanisms affecting roll durability are presented here. The thesis is concentrated on creation of a model in FEM program ANSYS. The final model is loaded with different rolling schemes and monitored stresses in a surface layer. The parameters obtained from the measurements performed in a rolling mill are applied as boundary conditions within the model.
137

Návrh jednoválcového vznětového zkušebního motoru / Design Study of 1-piston CI Engine

Plička, Ladislav January 2009 (has links)
Thesis deals with design study of 1-piston CI Engine for research purposes. The main purpose of this work is the design crankcase. Thesis includes background research conversant by various conceptions experimental motors. The numerice analysis of proposed crankcase in Pro ENGINEER MECHANICA (FME) software environment in also part of the work. Generally, the proposed solution of the experimental engine was focused on the universality and simplicity of the design.
138

Stanovení provozních podmínek upínacích čelistí zkušebního stroje MTS 810 / Assessment of service conditions of the screw grips of testing machine MTS 810

Votroubek, Tomáš January 2009 (has links)
This diploma thesis is aimed to assessment of safety of screw grips of testing machine MTS 810. Some parts of grips are predisposed to damage at low temperature (-180°C), e.g. spacer, isolating ceramics lamellas, etc. To guarantee its perfect function under hard laboratory conditions the finite element analysis was performed and suitable modifications grips parts have been suggested with respect to maximum of application of recent parts. Part of the thesis is devoted to suggestion of suitable tightening torque of experimental sample under different temperatures. For necessary numerical computations FEM system Ansys was used.
139

Návrh a pevnostní kontrola senzoru pro měření teplot a sil při válcování za tepla. / Design and stress analysis of temperature and force sensor in hot rolling process.

Nejedlý, Pavel January 2009 (has links)
In the process of hot rolling is roll surface thermo-mechanically stressed. To define lifetime of roll or to increase it by change of thermal mode, temperatures and forces acting on this roll need to be known. For this purpose should be used sensors, that are placed near by surface of roll. Aim of the first part of diploma thesis is to debug 2D computing model (MKP) to achieve the match of temperature graphs with experimentally measured values, which was recorded by temperature sensors in real process of rolling. In the second part the same temperature boundary conditions are applied on 3D model, which is used to solve mechanical strength check of the temperature sensor. The last part of thesis is design and verification of mechanical strength of the designed force sensor. The used boundary conditions were acquired in Laboratory of heat transfer and flow. The computing system ANSYS 11 is used to design a model of geometry and numerical calculation. This diploma thesis will be used as donating solution for the granted project, which started in this year with Laboratory of heat transfer and flow partnership.
140

Výpočtová analýza pevnosti a životnosti turbínových lopatek / Computational analysis of strength and fatigue of turbine blades

Polzer, Stanislav January 2009 (has links)
This master thesis deals with steam turbine blade attachment. Main goal is to perform strength analysis of the given geometry under static and cyclic loads by FEM and software ANSYS. Every particular model is described separately with mentioning of the problems which had to be solved. To create model of material, the tensile tests has been performed and results has been evaluate. There were planned and performed the low cycle fatigue tests to create a model of ultimate states which is used to evaluate the fatigue life of the attachment. Results of the nonlinear FEM analysis is discussed and some improvements of the geometry has been proposed to achieve better state of stress. Finally, the plan of future work has been proposed.

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