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Light Weight Mesh Experiments
Nováček, Richard ; Botta, Miroslav (referee) ; Šimek, Milan (advisor)
Semestral thesis deals new technology Lightweight Mesh and its implementation on a laboratory task to the subject of wireless sensor networks and the creation of appropriate documentation, which will serve as a basis to students. Also included is the use of serial communication, timer and ADC in Atmel Studio.
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Calculation and optimization of synchronous servomotor reluctance torque.
Kroupa, Martin ; Hájek, Vítězslav (referee) ; Ondrůšek, Čestmír (advisor)
This work is mainly focused on construction and design simulation of synchronous servomotor. This motor is built by 30 permanent magnets which are attached to rotor and solved in Ansoft Maxwell 14 software. The main purpose was to calculate reluctance torque, which is significant during the motor operational mode and its optimization. Ansoft Maxwell 14 can analyze in 2D mode as well as in 3D mode, for analysis it uses method of finite elements. Subjects can be analyzed in static conditions, or in any way of transient movement. Optimization in 2D, where we will change the shape in the area of air gap, will only be used as revision that the reluctance torque is bounded with this factor. The main simulations were supposed to be done in 3D model, where the role of rotation should have been taken in account to the final result. These simulations were replaced by alternative calculation. On behalf of achieved results, the optional rotation is stated in the end of my work.
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Distributed Ray Tracing in Reasonable Time
Slovák, Radek ; Polok, Lukáš (referee) ; Herout, Adam (advisor)
This thesis deals with the method of distributed ray tracing focusing on optimalization of this method. The method uses simulation of some attributes of light by distributing rays of lights and it produces high quality and partly realistic images. The price for realitic effects is the high computational complexity of the method. The thesis analysis the theory connected with these aspects. A large part describes optimalizations of this method, i.e. searching for the nearest triangle intersection using kd-trees, quasi random sampling with faster convergence, the use of SSE instruction set and fast ray - triangle intersection. These optimalizations brought a noticable speed - up. The thesis includes description of implementation of these techniques. The implementation itself emphasises the practical usability including generating some advanced animations and universal description of objects.
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Flow modelling for applications in process industry
Bialožyt, Michal ; Jegla, Zdeněk (referee) ; Hájek, Jiří (advisor)
Tato diplomová práce se zabývá vlivem zjednodušené geometrie na výpočet pomocí počítačového modelování proudění. Konkrétně se jedná o možnost náhrady části trubky porézní vrstvou, která má odpovídající tlakovou ztrátu jako nahrazený úsek. Řešen je také přestup tepla a jeho vliv na proudění a tlakovou ztrátu. Jako nejúčinnější řešení se ukázalo zakomponování vlivu přestupu tepla na tlakovou ztrátu do porézní vrstvy. Toto řešení nevyžaduje použití rovnice energie a je tudíž nejméně výpočetně nákladné. Získané poznatky jsou poté testovány na modelu reálného výměníku tepla, který má problémy se zanášením a distribucí proudu. Náhrada porézní vrstvou se ukázala jako spolehlivé řešení. Dalším bodem práce je testování závislosti výpočtu turbulentního difúzního spalování na jemnosti výpočetní sítě. K tomuto účelu byl využit model spalovací komory. Po prvním výpočtu byla výpočetní síť, na základě výsledků, zjemněna v oblasti vířiče a v oblasti plamene, kde dochází k největším gradientům. Po adaptaci výpočetní sítě bylo dosaženo téměř dvojnásobného počtu buněk a výpočet byl opakován. Výpočet s adaptovanou výpočetní sítí se ukázal být mnohokrát časově náročnější a byl proto zastaven jelikož přesahuje rámec této práce. Předběžné výsledky byly zpracovány.
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Numerical Modelling of Counter Flow in T-Junction
Míčka, Martin ; Šperka, Oldřich (referee) ; Štigler, Jaroslav (advisor)
The main objective of this master thesis is to implement the numerical modelling of the confluence of streams in the Tee-junction using Fluent CFD software. Modelling is carried out for different ratios of flow rates in steady flow. Calculations are evaluated, using a new mathematical model, by curves of loss coefficients. Furthermore, the influence of the selected type of the mesh in geometry on results from numerical modelling of flow is examined. Geometry of the Tee-junction is created in Gambit software. Finally, the results obtained from numerical modelling are confronted with results from an experiment.
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Unstructured Mesh Generation
Rozehnalová, Petra ; Roupec, Jan (referee) ; Hlavička, Rudolf (advisor)
Meshes based on triangulation (2D) or tetrahedralization (3D) are widely used in applications such as computer graphics, interpolation, surveying, and terrain modelling. Although the most important use is in numerical methods for the solution of partial differential equations. This solution is use for simulation of complex physical processes, which are described by this equations. The main topic of this thesis is mash generation.
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Verification of nonlinear material models of concrete
Král, Petr ; Němec, Ivan (referee) ; Hradil, Petr (advisor)
Diploma thesis is focused on the description of the parameters of nonlinear material models of concrete, which are implemented in a computational system LS-DYNA, interacting with performance of nonlinear test calculations in system LS-DYNA on selected problems, which are formed mainly by simulations of tests of mechanical and physical properties of concrete in uniaxial compressive and tensile on cylinders with applying different boundary conditions and by simulation of bending slab, with subsequent comparison of some results of test calculations with results of the experiment. The thesis includes creation of appropriate geometric models of selected problems, meshing of these geometric models, description of parameters and application of nonlinear material models of concrete on selected problems, application of loads and boundary conditions on selected problems and performance of nonlinear calculations in a computational system LS-DYNA. Evaluation of results is made on the basis of stress-strain diagrams and load-displacement diagrams based on nonlinear calculations taking into account strain rate effects and on the basis of hysteresis curves based on nonlinear calculations in case of application of cyclic loading on selected problems. Verification of nonlinear material models of concrete is made on the basis of comparison of some results of test calculations with results obtained from the experiment.
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Air flow load on a roof structure induced by a helicopter during erection works
Fidler, Tomáš ; Križan, Jiří (referee) ; Nevařil, Aleš (advisor)
Diploma thesis is focused on modeling rotor downwash generated by the main rotor of helicopter and analyzing its effects on the roof structure. Theoretical definition of rotor downwash flow is described in the first part of the text. Governing equations of computational fluid dynamics are briefly explained as well as boundary layer and finite volume method. Next part inquires into numerical simulation of rotor downwash based on height of rotor above the roof, shape of roof plane and climatic conditions. Results are compared with climatic load values provided by actual Czech construction standard in the end of the text.
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System for digital short-range wireless communication
Rébl, Miroslav ; Kolka, Zdeněk (referee) ; Tošovský, Petr (advisor)
This project includes the design of the System for digital short-range wireless communication. The methodology of the communication between net only one device type based system is proposed. The thesis describes system communication rules and used ways for protection of a correct transmission. Furthermore,the project descibes realizasion of the digital wireless communication with selected functions.
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Calculation of heat and force field UniGear ZS1
Mokrý, Lukáš ; ABB, Drahomír Tůma, (referee) ; Dohnal, Petr (advisor)
The aim of my work is to describe high-voltage switchgear type UniGear 500R, which is part of UniGear switchgears family. I will focus on heating issue of one 500R unit and its parts during operation. Maximum values of this heating is limited by standards and can´t be exceed to ensure safe and reliable operation. That is why the heating tests are necessary part of designing and developing switchgears. Calculation will be made by two different ways. First is classic one-pole heating net method and second is numerical simulation in Solidworks flow simulation program. Except the theoretical description there will be presented also used 3D model and explanation of both method, used to calculation and simulation. Last point of this work is measuring of this type of switchgear and getting real data. The main point there is to compare measured values with values calculated and decide if is possible to simulate tests with appropriate accuracy. Then would be also possible to substitute the real test in laboratory, which costs many thousand crowns and takes lots hours of time. This work is collaborated with EJF division of ABB Company, where I am employed. Heating issues in this company is always on process, because of developing and improving of their products. So this work could be helpful in this field. ABB provides all materials needed, especially technical catalogues, 3D model and final values from laboratory measuring. Support from college faculty is mainly in study consultations and proposing of calculations making. In the end of work will be make final comparison and evaluation of achieved results.
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