This thesis describes an innovative method for topographic measurement of diffuse surfaces. Tested surface is measured indirectly using nanoparticles distributed across the studied area. An image of every particle is captured by CCD camera as a double helix point spread function whose angular rotation corresponds to local surface height. Used point spread function is the result of an interference of non-diffracting vortex beams that are formed by a spiral phase mask from light originating from a nanoparticle. Diploma thesis presents an overview of current techniques for surface topography measurement. Next, working principle of proposed method is described and its experimental application is discussed. An influence of signal-to-noise ratio and image sampling on reconstruction precision is studied using numerical simulations and, as a result, optimal experimental parameters are proposed. Practical potential of the method is demonstrated by 3D reconstruction of planar and spherical surfaces in the depth range of up to 9 times the depth of focus of used microscope objective.

This diploma thesis deals with the design and creation of an algorithm for generating simulated signal data from a vibration diagnostics device. The first part is focused on theoretical acquaintance with vibration diagnostics and characteristics of individual defects of rotary machines. The next part deals with the possibilities of mathematical and kinematic simulations using a computer software. The main part of this work is dedicated to design and creation of software for generating simulated signal data. In the last part, the principle of simulation of specific defects of rotary machines is clearly demonstrated.

This thesis deals with the reactive power compensation, namely the possibility of reactive power compensation in Petrochemie company using a passive power factor correction system instead of synchronous generators, as part of the contract Kompel company. The thesis analyzes problems of definition of power in circuits with sinusoidal and nonsinusoidal voltages and currents. Furthermore, this thesis describes the power factor correction systems used in the low and medium voltage industrial and distribution networks. The last four chapters contain description of the existing state of power plant in Petrochemie company. There are considered the possibility of use of existing power factor correction system owned by company. The new static power factor correction system is suggested and functionality of power factor correction systems is verified through the simulations.

This thesis deals with a procedure for determining the complete processing of aerodynamic flow instabilities (rotating stall and surge) in a centrifugal compressor. At small flows the performance of a compressor system is limited by the surge line, which is caused by flow instabilities. Numerical solution is obtained using the method of transfer matrix. This system is simulated through several models with local resistances that represent the dissipation of pressure energy. Pulses are excitated in these models by the pressure jump placed before the centrifugal compressor. From the frequency-amplitude characteristics for the selected range of frequencies and flow the impedance characteristic of the compressor system is determined. We are looking for problematic frequencies in this characteristic that cause flow instabilities in the compressor system.

The main purpose of this master’s thesis is to propose the methodology suitable for experimental evaluation of additional mass, stiffness and damping by which a liquid layer in the sealing gap affects the rotor. Sealing gaps are important structural elements of hydrodynamic machines. An appropriate design of a sealing gap including the additional effects determination is an inevitable part of the machine overall dynamic design. The thesis also provides a literature search in the field of rotor dynamics and additional effects of a liquid. The designed experiment aiming to determine additional effects of the liquid is based on rotor dynamics evaluation by means of the radial forces measurement. The experiment results were used to determine dynamic properties of dry and wet rotor of the testing device.

The aim of the master’s thesis is an investigation of volume mesh quality, turbulent models and models of rotation and their influence on aerodynamic coefficients of rotating wheels. Mesh independence study and near-wall prism layer modelling are also of high importance. Subsequently, the appropriate turbulent model is used for research of wheel rotation on drag and lift on a front and rear axle of the vehicle compared to the stationary case.

This dissertation thesis deals with the computational modelling of the dynamic response of the rotating electrical machine structure on the application of the magnetic forces. Apart from the dynamic response of the ideal symmetrical machine, the influence of the air gap eccentricity on the dynamics response is studied in this work. A basic type of the air gap eccentricity, which is caused by eccentric mounting of the rotor pack on the shaft of the rotor, is considered. The calculations the dependence of the magnetic forces on the time and a misalignment of the rotor pack are performed as first. The computational model of the magnetic field of the rotating electrical machine, which is based on solution of the electromagnetic coupled field analysis by finite element method, is used for this purpose. An analysis of the influence of the unbalanced magnetic pull and the stiffness of some parts of the machine on the modal properties of the machine is performed in the second part of this thesis. A third part of this thesis is focused on the calculation of the dynamic response of the machine during the steady state operation of the machine and the influence of the rotor pack misalignment on the dynamic response is studied. The obtained results showed that the tangential components of the magnetic forces, which act on the stator pack, excite significant torsional vibration of the stator. Besides the vibration of the stator of the machine, the influence of the rotor pack misalignment on the sound power of the machine, vibration of the rotor, loads of rotor bearings and air gap eccentricity is studied in this thesis.

The aim of this diploma thesis was to design experimental setup for planar samples erosion by means of the water jet on the rotational sample configuration, laboratory experimental testing and its evaluation by means of the 3D optodigital microscope Olympus DSX 510. There were observed typical erosion patterns at the solid tested material surfaces as well as the cavitation erosion. Experiments were carried out at the following water pressures: 0.432 MPa, 1.50 MPa on the rotating sample, at 2.50 MPa on steady sample and on flooded sample for different treatment times. Experimental results of waterjet impact on rotating sample were compared with the theoretical modelling data obtained by CFD modelling. Computational modelling was done in two parts: 3D modelling of water jet flow impact on rigid steady surface and 3D modelling of water jet impact on rigid moving surface. The latter modelling was solved as two phase modelling, where the computational model “Volume of Fluid” was employed. The aim of the study was to find out for the individual cases under study appearance of the water flow and the changes of the magnitude of the force of the impinging water jet on the wall.

This diploma thesis discusses the issue of the fluid flow instabilities due to rotating discs. It also deals with the calculation of axial force in centrifugal pumps and pressure distribution on cover and support disc of the impeller. Computational simulation of rotating disc is presented with the aim of capturing flow instabilities. Next computational simulation focuses on modelling a gap between the support disc (rotor) and the stator part of the pump for three different geometries, where axial force, pressure distribution on the support disc and loss torque are calculated for each of three models. Obtained results are then compared with the experiment in the conclusion

This diploma thesis deals with modeling and CFD calculation of aerodynamic characteristics of vehicle, influenced by loaded or unloaded tires and boundary conditions applied on this tires. These calculations are combined with three types of variable rear body shape of DrivAer vehicle. There is a complete analysis and evaluation of the effects of these factors.