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Pressure and velocity pulsations of liquid in thin cylindrical domain
Oborná, Eliška ; Pochylý, František (referee) ; Habán, Vladimír (advisor)
The subject of this diploma thesis is a dynamic analysis of phenomena occurring in the thin cylindrical region, ie in a gab, which flows liquid by the given parameters. Through the simplifications introduced, it comes to the problem of structural and forced vibration for both the horizontal pulsation in a tube and the area of a compensating piston. The described method uses the separation of variables for pressure function. The speed function is derived from the already known pressure field distribution using the Navier-Stokes equation.
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CFD simulation of pressure pulse propagation in twin scroll volute with shifted divider
Dohnal, Jiří ; Tuhovčák, Ján (referee) ; Katolický, Jaroslav (advisor)
The main subject of this Master’s thesis is a review of turbo-charger efficiency with split turbine channel in the process of various types of supercharging and also with diverse designs of so called divider of turbine channels. I used CFD simulation utilizing Star CCM+ software. A model of turbocharger and mesured data came from commercial model. Efficiency is evaluated on the basis of performance distributed to the turbine with similar input conditions for both steady and unsteady process. For better understanding of this subject I also included theoretical basics of supercharging of combustion engines and fluid dynamics.
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Thermodynamic Conditions in Quenching Chamber of Low Voltage Circuit Breaker
Urban, Ferdinand ; Hüttner,, Ľudovít (referee) ; Kapička, Vratislav (referee) ; Aubrecht, Vladimír (advisor)
Práce se zabývá studiem procesů probíhajících při zhášení silnoproudého oblouku ve zhášecí komoře jističe. Je zaměřena na výpočet dynamiky tekutin a teplotního pole v okolí elektrického oblouku. V práci je dále popsán vliv vzdálenosti plechů v komoře a vliv tvarů plechů z hlediska aerodynamických podmínek uvnitř komory. Dalším cílem dosaženým touto prací je poskytnutí informací o vlivu polohy elektrického oblouku na termodynamické vlastnosti uvnitř komory. Toto je důležité, zejména pokud je oblouk do komory vtahován jinými silami, např. elektromagnetickými a během tohoto vtahovacího procesu mění svůj tvar i polohu. Za účelem co nejjednoduššího, ale zároveň co nejefektivnějšího řešení úkolu, byl vyvinut software určen speciálně pro výpočet dynamiky tekutin numerickou metodou konečných objemů (FVM). Tato metoda je, v porovnání s rozšířenější metodou konečných prvků (FEM), vhodnější pro výpočet dynamiky tekutin (CFD) zejména proto, že režie na výpočet jedné iterace jsou menší v porovnání s ostatními numerickými metodami. Další výhodou tohoto softwarového řešení je jeho modularita a rozšiřitelnost. Cely koncept softwaru je postaven na tzv. zásuvných modulech. Díky tomuto řešení můžeme využít výpočtové jádro pro další numerické analýzy, např. strukturální, elektromagnetickou apod. Jediná potřeba pro úspěšné používání těchto analýz je napsáni solveru pro konečné prvky (FEM). Jelikož je software koncipován jako multi–thread aplikace, využívá výkon současných vícejádrových procesorů naplno. Tato vlastnost se ještě více projeví, pokud se výpočet přesune z CPU na GPU. Jelikož současné grafické karty vyšších tříd mají několik desítek až stovek výpočetních jader a pracují s mnohem rychlejšími pamětmi, než CPU, je výpočetní výkon několikanásobně vyšší.
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Fluid Dynamics Simulation Using Cellular Automata
Režňák, Michal ; Janoušek, Vladimír (referee) ; Peringer, Petr (advisor)
The main objective of this work was to create application for fluid flow simulation using Lattice Gas Cellular Automata. Used simulation models are HPP, FHP-I, FHP-II and FHP-III. The program is implemented in a C++ language in a way that it can run in WebAssembly web standard. Part of the work is comparison between wasm, ams.js formats and native desktop (x86_64). This shows that time for application loading in web browser is much smaller for wasm format than for asm.js and application performance in wasm format is about 24% higher than asm.js but 50% smaller than a native desktop. The application is suitable for educational purpose as a presentation of cellular automata simulation and also as an introduction to the Lattice Boltzmann method for fluid flow simulation.
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Realistic Smoke Animation
Zubal, Miloš ; Španěl, Michal (referee) ; Sumec, Stanislav (advisor)
This work makes basic analysis of historical and current algorithms for smoke animation. Modern approaches to rendering volumetric data are briefly described. We choose algorithms for implementation on basis of this analysis. These algorithms are described in detail and we make emphasis on their important properties according to dedication of this work. Detailed description of implementation follows along with performance measurement. Conclusion evaluates results of work and proposes possible extensions.
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Simulations of Photobioreactors from Hydrodynamics and Mass Transfer Point of View
Rebej, Miroslav ; Turek, Vojtěch (referee) ; Jördening, Alexandra (referee) ; Jegla, Zdeněk (advisor)
Simulations of photobioreactors with microalgae-specific cultures is a field that connects microbiology with the multiphase fluid dynamics. With microalgae cultivation, it is necessary to account various phenomena, e.g., multiphase hydrodynamics with water, CO2 bubbles and microalgae, multiphase species mass transfer, radiation transport, light attenuation, growth and culmination of microalgae and their effect on fluid properties. Computational model presented in this doctoral dissertation thesis links multiphase hydrodynamic model and the species mass transfer model. In the thesis, there is an overview of applicable computational models for the given types of photobioreactors. The multiphase hydrodynamic model and the species mass transfer model then draw from this overview. Next, the accuracy of these sub-models was compared with laboratory experiments. As a result, the developed computational model of the photobioreactor can be further extended with other sub-models, i.e., the irradiation model and the biomass growth model.
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Adaptive Simulation of Large-Scale Ocean Surface
Krijt, Filip ; Kadleček, Petr (advisor)
Physically-driven methods of simulating fluid dynamics and frequency-based ocean surface synthesis methods are of long-standing interest for the field of computer graphics. However, they have been historically used separately or without any interaction between them. This thesis focuses on the possibility of combining the approaches into one adaptive solution by proposing methods for unified surface representation, method result blending and one-way interaction between the methods. The thesis also outlines several future developments of the combined method and proposes a level-of-detail approach taking advantage of hardware tessellation that can be used regardless of what method was used for the simulation. Powered by TCPDF (www.tcpdf.org)
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Realistic Smoke Animation
Zubal, Miloš ; Španěl, Michal (referee) ; Sumec, Stanislav (advisor)
This work makes basic analysis of historical and current algorithms for smoke animation. Modern approaches to rendering volumetric data are briefly described. We choose algorithms for implementation on basis of this analysis. These algorithms are described in detail and we make emphasis on their important properties according to dedication of this work. Detailed description of implementation follows along with performance measurement. Conclusion evaluates results of work and proposes possible extensions.
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Fluid Dynamics Simulation Using Cellular Automata
Režňák, Michal ; Janoušek, Vladimír (referee) ; Peringer, Petr (advisor)
The main objective of this work was to create application for fluid flow simulation using Lattice Gas Cellular Automata. Used simulation models are HPP, FHP-I, FHP-II and FHP-III. The program is implemented in a C++ language in a way that it can run in WebAssembly web standard. Part of the work is comparison between wasm, ams.js formats and native desktop (x86_64). This shows that time for application loading in web browser is much smaller for wasm format than for asm.js and application performance in wasm format is about 24% higher than asm.js but 50% smaller than a native desktop. The application is suitable for educational purpose as a presentation of cellular automata simulation and also as an introduction to the Lattice Boltzmann method for fluid flow simulation.
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