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Visualization of air jet from ventilation outlet of a passenger car dashboard
Bečica, Radek ; Bělka, Miloslav (referee) ; Lízal, František (advisor)
Goal of this master´s thesis is to experimentally analyse air jet from ventilation outlet of a passenger car dashboard using smoke visualization and to describe this air jet. Air flow was set at 30 m3/h according to requirements from Škoda Auto s.r.o. from previous experiments on a similar ventilation outlet. First type of measuring rig which was developed for previous experiments was disassembled and replaced with a new modern measuring rig which is supposed to be used for next visualizations and experiments. Visualization was performed using smoke method and laser light plane. Air jet was photographed for five defined ventilation outlet adjustments and that for a jet to free space and for a jet flowing along a wall. The wall represented a front left door of a car. Results were processed by computer and presented as pictures and tables. Resulting angles were transformed to the main coordinate system of a car. Ventilation outlet functionality with respect to the air distribution in a car was evaluated afterwards.
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Influence of fractal geometry on turbulent flow
Hochman, Ondřej ; Štefan, David (referee) ; Rudolf, Pavel (advisor)
The master’s thesis deals with computational fluid dynamics (CFD) of two orifices, that have different shapes of holes but similar cross-sectional flow areas. The first of them is orifice with circular-shaped hole, which is used for maintenance free measurement of flow. The second one is orifice with fractal-shaped hole, inspired by von Koch snow-flake. This thesis follows bachelor thesis, in which was experimentally examined, that fractal-shaped orifices have better hydraulic properties (hydraulic losses and lower pressure pulsations) than circle-shaped one. The main target is to confirm this conclusion based on experiment, this time using CFD with various types of turbulence modelling ap-proaches. Both single phase (cavitation free) and multiphase numerical simulations were realized. Each model was compared from perspective of hydraulic and dynamic charac-teristics.
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Flow measurement of air by multiport averaging probes
Šimák, Jakub ; Uher, Miroslav (referee) ; Šedivá, Soňa (advisor)
Master work deals with the measurement of fluid flow (particularly air) pipe, with orifice and multiport averaging probe. The theoretical part is followed by practical, which verifies the properties of the measured system. In a next part of semestral work are verifies the properties of multiport averaging probes Vavra s.r.o. MQS-011 and Rosemount Annubar 485. Measured values from probes are compared.
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The membrane wall of the boiler with an advanced flow control
Češla, Martin ; Tomáš, Zdeněk (referee) ; Tomáš,, Zdeněk (referee) ; Ing.Tomáš Zdeněk (referee) ; Pospíšil, Jiří (advisor)
The master thesis deals with hydraulic characteristics of once-through boilers and describes the problems which may arise during the flow of water through the evaporator. Especially the formation of aperiodic instability of the evaporator and hydraulic uniformity amongst every steam generating tube. The thesis describes parameters, which cause these problems, and solutions how to deal with them. The calculation has been done for evaporator of the boiler called K2 located in power station in Chvaletice.
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Steam turbine - condensation formation and discharge
Zouhar, Adam ; Filip, Patrik (referee) ; Fiedler, Jan (advisor)
Master thesis is dealing with the issue of condensate creation and removal from the Nesher Ramle steam turbine during start-up and steady state. At the beginning a preliminary calculation of heat balance and the turbine itself is done. It is followed by description and design of drainage system supplemented by calculation of the steam flow through the orifices. Steam flow calculation was done via S. D. Morris, Pavelek with Kalčík and Ambrož, all three methods were compared. The main goal is the theoretical calculation of the amount of condensate created during start-up which is influenced by its initial state from which it is started. Three default states are considered, cold, warm and hot. In the last chapter the comparison of theoretical calculation with the measured data on real turbine is done and it is supported by the evaluation of the data from the measurement of the steam turbine at steady state on maximum power and half power. From the steady state analysis, percentage of water flow to expander from the total amount of condensate formed in the turbine were obtained.
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CFD analysis of the airflow for the different types of flowmeters
Drexler, Pavel ; Štohl, Radek (referee) ; Šedivá, Soňa (advisor)
There are some basic information about pressure sensors and flow in the first part of my diploma thesis. For example turbulent and laminar flow, construction of pressure sensors and basic information abaut Ansys and –Fluent. Main part of this thesis is focused on CFD simulation of pressure and velocity in the vicinity of pressure sensors. I confront this simulated values with measured values in final part of this thesis.
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Fractal geometry application for orifice plate design
Hochman, Ondřej ; Fic, Miloslav (referee) ; Rudolf, Pavel (advisor)
Bachelor thesis consists of three parts. The first part is focused on research study of cav-itation and fractal geometry. It is concerned with the physical principle of cavitation, its generation, dynamics and implosion of cavitation bubbles. It also turns attention to useful application. Brief explanation of fractal geometry follows, including some famous examples. Two fractal shaped orifices were designed in the second experimental part, having the same cross-section as orifice with ordinary circle hole. These orifices were compared to each other from perspective of hydraulic losses.
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Influence of fractal geometry on turbulent flow
Hochman, Ondřej ; Štefan, David (referee) ; Rudolf, Pavel (advisor)
The master’s thesis deals with computational fluid dynamics (CFD) of two orifices, that have different shapes of holes but similar cross-sectional flow areas. The first of them is orifice with circular-shaped hole, which is used for maintenance free measurement of flow. The second one is orifice with fractal-shaped hole, inspired by von Koch snow-flake. This thesis follows bachelor thesis, in which was experimentally examined, that fractal-shaped orifices have better hydraulic properties (hydraulic losses and lower pressure pulsations) than circle-shaped one. The main target is to confirm this conclusion based on experiment, this time using CFD with various types of turbulence modelling ap-proaches. Both single phase (cavitation free) and multiphase numerical simulations were realized. Each model was compared from perspective of hydraulic and dynamic charac-teristics.
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Steam turbine - condensation formation and discharge
Zouhar, Adam ; Filip, Patrik (referee) ; Fiedler, Jan (advisor)
Master thesis is dealing with the issue of condensate creation and removal from the Nesher Ramle steam turbine during start-up and steady state. At the beginning a preliminary calculation of heat balance and the turbine itself is done. It is followed by description and design of drainage system supplemented by calculation of the steam flow through the orifices. Steam flow calculation was done via S. D. Morris, Pavelek with Kalčík and Ambrož, all three methods were compared. The main goal is the theoretical calculation of the amount of condensate created during start-up which is influenced by its initial state from which it is started. Three default states are considered, cold, warm and hot. In the last chapter the comparison of theoretical calculation with the measured data on real turbine is done and it is supported by the evaluation of the data from the measurement of the steam turbine at steady state on maximum power and half power. From the steady state analysis, percentage of water flow to expander from the total amount of condensate formed in the turbine were obtained.
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Fractal geometry application for orifice plate design
Hochman, Ondřej ; Fic, Miloslav (referee) ; Rudolf, Pavel (advisor)
Bachelor thesis consists of three parts. The first part is focused on research study of cav-itation and fractal geometry. It is concerned with the physical principle of cavitation, its generation, dynamics and implosion of cavitation bubbles. It also turns attention to useful application. Brief explanation of fractal geometry follows, including some famous examples. Two fractal shaped orifices were designed in the second experimental part, having the same cross-section as orifice with ordinary circle hole. These orifices were compared to each other from perspective of hydraulic losses.
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