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Cavitation erosion testing
Sochorec, Rostislav ; Moravec, Prokop (referee) ; Rudolf, Pavel (advisor)
The thesis is a literature survey of three most common methods of accelerated tests of cavitation erosion. These are cavitation induced by changing flow velocity in relatively conventional high-speed water tunnels, vibratory method which uses ultrasound to produce cavitation, and jets of liquid impacting surface of materials. In order to understand them, there is also a brief general introduction to the issue of cavitation and most important factors which can have effect on cavitation tests results.
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Rocket fuel pumps
Kalina, Adam ; Sluše, Jan (referee) ; Rudolf, Pavel (advisor)
This bachelor thesis deals with the pumps used in rocket technology, their operating parameters and general geometry. Particular attention is paid to inducers. Their influence on cavitation in pumps and overview of the different types that are used in various rocket engines. Is mentioned here how cavitation is created, what are the types of cavitation and its impact on the operation of the pump.
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Cavitation erosion
Lecnar, Lukáš ; Hudec, Martin (referee) ; Rudolf, Pavel (advisor)
This bachelor’s thesis focuses on cavitation erosion and it is divided into two main parts. The first part is devoted to the search of cavitation erosion focusing on erosion mechanisms. In the first chapter of this search is briefly described cavitation process and different types of cavitation are listed here. Hydrodynamic cavitation which is the key type for this bachelor’s thesis is described in the following chapter. The final and the most extensive chapter is devoted to cavitation erosion of solids which is largely associated with the effects of the mechanical action of the fluid. The second part is devoted to the experimental study of cavitation erosion of samples. The goal was to document the experiment which was carried out in order to gain knowledge about the material removal by cavitation erosion.
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Nucleation rate in binary cavitating systems - A comparison of experimental data and classical nucleation theory predictions
Němec, Tomáš
A brief review of recent literature on proton exchange membrane fuel cell (PEMFC) modelling is presented and the governing equations of the transport processes in the proton exchange membrane are presented. Consequently, the model of water transport in the membrane electrode assembly of a fuel cell in commercial software FLUENT is investigated. The aim of this work is to test the possibilities of the PEMFC modelling using FLUENT. Special attention is given to the water management and the properties of the fuel cell membrane.of four binary mixtures, i.e. diethylether - nitrogen, propane - carbon dioxide, isobutane - carbon dioxide, and chlorodifluoromethane - carbon dioxide. The predictions of the classical nucleation theory show very good agreement with the measured nucleation rates.
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