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CFD Simulation of a Sub-millimetre Rising Bubble in a Stagnant Liquid.
Crha, Jakub ; Basařová, P. ; Kašpar, O.
Hydrodynamics of the multiphase apparatus is strongly affected by fluids used in the process. One of the main quantities, which determine the hydrodynamic behaviour is the rising velocity of gaseous bubbles. This velocity can be determined easily in small scale apparatuses, but it can be much more challenging in industrial-scale devices. For that reason, mathematical modeling is used. COMSOL Multiphysics, finite element CFD solver, was used to describe the behaviour of the single bubble rising in aqueous solutions of ethanol and n-propanol. Aqueous solutions of low-carbon alcohols are extensively used in many multiphase chemical processes such as distillation, flotation and in multiphase reactors. Bubble velocities and shapes obtained from the simulation were compared to experimental and theoretical values. Two initial diameters of bubbles were used – 0.6 and 0.8 mm. Terminal velocities and shapes deformations obtained from COMSOL of 0.6 mm bubble were in an agreement with theoretical and experimental values.
Plný tet:  PDF
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Collision of a Small Bubble with a Large Falling Particle
Vejražka, Jiří ; Hubička, M. ; Basařová, P.
The motion of a tiny bubble (< 1mm) in a neighborhood of a solid sphere falling through a liquid is studied. A model assuming irrotational flow around the sphere and spherical bubble shape is provided; this model is validated by comparison with the experiment. The model can be further simplified by neglecting inertial forces, which are negligible in present experiments. Results of the model are provided also for the opposite limit, in which the inertial forces are dominating the bubble motion.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22014011511310 - PDF
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Associative Anaphora in the Milan Kundera´s Novel "Žert" - Identification, Functioning, Formal Exponents
BASAŘOVÁ, Petra
This thesis deals with questions of so called associative anaphora, which represents one of means of textual references. Firstly, the term is generally delimitated after a study of specialized literature. Then, the analysis is demonstrated at the French version of the novel by Milan Kundera called "La Plaisanterie" and the sequences found in this book are commented and classified on the basis of given criteria into several subcategories. The emphasis is put on semantic relations between coreferential segments and possible influence of using of determiners on functioning of these relations. In addition, the work aims to focus whether the associative link and lexical stereotypes are connected. The final task of this work is the comparison with Czech original and there is demonstrated by a summary what language means are used in Czech language to express such anaphoric links.
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Reforms of the European Parliament from the beginning till 2010
Bašarová, Petra ; Karpová, Eva (advisor) ; Machytka, Daniel (referee)
This bachelor thesis tries to describe main moments of the development of the European Parliament. The European Parliament is one of the most important institutions of the European Union. As the only European institution represents direct interests of citizens. During the development of the European integration his importance and role was changed. In the history it had to face many problems, but nowadays represents European institution, which can markedly influence functioning of the European Union. The first chapter describes the beginning of the European parliament till the period of adopting the Maastricht treaty, the second chapter is focused on the development in 90's and in the beginning of the new century. The third chapter deals with changes that the Lisbon treaty brought.
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Theoretical Description of Motion of a Spherical Bubble in Neighbourhood of a Falling Particle
Basařová, P. ; Vejražka, Jiří ; Zedníková, Mária ; Hubička, M.
The aim of this work is to broaden the knowledge of the hydrodynamic interactions that occur between bubbles and solids of a comparable size. Focusing on collision processes between a single rising bubble with mobile surface and a larger falling solid spherical particle in stagnant liquid, the theoretical model describing the bubble trajectory is given here. The model is based on forces acting on the bubble and utilizes also equation for the bubble motion. The bubble is considered to be spherical and its motion is straight and rectilinear. The particle is spherical and moves vertically down with a steady velocity; the flow around the particle is axially symmetric.
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