This thesis is focused on the thermal-hydraulic and construction design of heat exchanger with floating head. The introductory part is dedicated to the design of heat exchangers. Next part is focused on the thermal-hydraulic design created in HTRI software (module Xist. The next section is the strength calculation of selected components of the heat exchanger according to EN 13445 in software Sant'Ambrogio. The following part describes each of the analysis in software Ansys Workbench. The final part contains complete manufacturing documentation of heat exchanger.

Final thesis describes two variants of computational models to simulate cross-roll leveling of rods, which are based on the Lagrangian approach to describe the continuum. Implementation of both variants was performed in ANSYS software, and their main difference lies in the choice of the type of elements for the discretization. An integral part of this thesis is the description of the principle, which is an evaluation of the curvature of the rod after completion of the simulation leveling. In the other part of the work are presented the results, which are then compared with realized experiment and simulation algorithm for cross-roll leveling based on the Euler approach. The final part is dedicated to the optimal settings of the leveller.

Thesis deals with the compatibility of vehicles in a frontal collision. The first section discusses about compatibility from different views. There are the physical processes used in the mechanics of impact. The second part is focused on solving the compatibility of vehicles in a frontal collision by crash analysis using the finite element method. Firstly there are described collisions of vehicles from different vehicle classes (small cars, lower middle class, Pick up / SUV) into the fixed barrier by the US NCAP. Furthermore there are simulated head-on collisions of vehicles from different vehicle classes. In the end there is shown the possibility of using data from crash tests to determine the EES.

This Master thesis is based on problems of force effects of the magnetic field of short-circuit current. Firstly, I analysed the force action of the three phase busbars during the three-pole short circuit. The analysis was performed in the Ansys Maxwell program and I verified the correctness of the analysis by numerical calculation. The second practical part was executed for ABB company. The main task was to analyse the force effects of the short-circuit current in the HV switchgear with focusing on the arms and contact system of the circuit breaker. The simulations of the following configurations were performed in more details: three configurations of the simplified VD4 circuit breaker, two types of VD4 circuit-breaker contact systems and a linear circuit breaker configuration model. The objective was to calculate the forces acting on the current path of the arms and contact system of the VD4 circuit breaker during the three-phase short-circuit and to simulate the effects of forces on these current parts. For modelling of individual assemblies, calculations and simulations I used: SolidWorks 2014, Ansys Maxwell 16.0 and Ansys Workbench 14.5 programs. With SolidWorks 2014 3D CAD software were modelled simplified assemblies of circuit breakers and contact systems. These systems were imported into the Ansys Maxwell software, where the force effects of the magnetic field of the short-circuit current were calculated. In Ansys Workbench programme was simulated the effect of forces on the current circuit breakers. Moreover, the final deformations of the materials (with respect to the mechanical properties of the structure) were plotted. The analysis of force effects of the magnetic field was performed for the specified static short - circuit current value.

The thesis is focused on a test on determination of the fracture-mechanical parameters of quasi-brittle materials, especially concrete. What is referred to as the wedge-splitting test is considered, for which a variety of shapes of notched specimen can be used. This work is exclusively focused on the cylinder-shaped specimen of diameter 150 mm and breadth of 100 mm. The test is performed virtually using Atena 2D FEM software. Progress of failure is observed during loading of the specimen for various notch lengths. The amount of energy released for the development the failure outside of the tested cross-sectional area (weakened by the notch) is quantified and the size of the fracture process zone is investigated. The described analysis is performed for several material sets witch differ in cohesive properties of the quasi-brittle material expressed via the so-called characteristic length. Suitable proportions of the test specimen are sought, in order to avoid the failure and thus also the energy dissipation outside of the specimen ligament area during the experimental tests, which shall lead to more accurate estimates of fracture-mechanical parameters of the tested material.

The presented dissertation thesis is focused, as the title suggests, on the analysis of stress state aspects of quasi-brittle fracture. That means the fracture of composite materials with cement matrix (such as concrete, mortar, plaster, etc.), ceramics and other composites. Used methods are based on the theory of multi-parameter linear elastic fracture mechanics, which highlights the importance of considering of several initial terms of Williams power series, approximating the stress and displacement fields in a cracked body, within conducted fracture analyses. Determination of values of coefficients of terms of this series, recalculated into the shape functions serving in most of the conducted stress state analyses, is performed via the so called over-deterministic method. Another tool for the problem solving is nonlinear fracture mechanics, represented primarily by the cohesive crack model, namely the crack band model implemented in the used ATENA software. For the backward reconstruction of stress field in the cracked bodies the application ReFraPro is used. The analytical part deals with various aspects of wedge-splitting test – from the boundary conditions, though various possibilities of nodal selection (required as input variables for the over-deterministic method) up to the advanced (automated) analysis of numerical model. Special chapter includes atypical test specimens designed for adjusting of various levels of constraint of stress and deformation at the propagating crack tip. The study of this geometry and also the subsequent detail analysis reveals important information for real experiments. Backward reconstruction of stress field presents analysis on suitable possibilities of nodal selections as inputs into the procedure of approximation of the crack tip fields and answers the question of the necessity of application of the multi-parameter linear elastic fracture mechanics for certain fracture analyses of specimens from quasi-brittle materials. The th

The purpose of this work is to introduce explicit finite element method (FEM) and to familiarize with commercial software tools witch are capable to perform simulations. The technological conditions and the scope of application of roller burnishing are described in subsequent part. The simulation model of roller burnishing was created. Software ANSYS LS-DYNA was used to make computations. The results of simulation and technical and economical benefits of roller burnishing are presented in the conclusion.