|
|
Experimental verification of flood hose bag functionality
Valdová, Klára ; Dráb, Aleš (referee) ; Žoužela, Michal (advisor)
This bachelor's thesis deals with functionality verification of one type of flood protection system. It is a large-volume hose bag Protex-K with the nominal diameter of 680 mm, which is supplied by the company KOEXPO OSTRAVA, joint stock company. The bag is made of polyethylene fabric and filled with cement and fly ash mixture, which is fed into the bag by means of screw pumps. The first part of the work is focused on the classification of flood barriers and their laboratory tests. The bag with the nominal diameter of 680 mm underwent the stability test, its discharge coefficient and specific leakage were determined. The volumic mass of the cement-flyash mixture was determined both in the dry and in the saturated condition. All these tests were performed in the laboratory of Water Management Research of the Faculty of Civil Engineering Brno University of Technology. The work also includes the data obtained by measuring, processed and presented in the tabular and graphical form.
|
|
|
Experimental verification of flood kidney three bag functionality
Požárová, Miroslava ; Dráb, Aleš (referee) ; Žoužela, Michal (advisor)
This bachelor's thesis deals with the system of large-volume flood bags Protex - K manufactured by the company KOEXPRO OSTRAVA, joint stock company. The bags consist of polyethylene fabric filled with cement and fly ash mixture. The system enables creation of many shape modifications. One of them is the so-called triplet formed from three hose bags with the nominal diameter of 300 mm. The goal of the work was to verify functionality of this bag in one of the hydraulic troughs in the Laboratory of Water Management Research of Department of Water Structures of the Faculty of Civil Engineering, Brno University of Technology. To assess the functionality, the bag stability was tested with various water levels, and discharge coefficient and specific leakage per one standard meter of the bag was determined. The resulting discharge coefficient was compared with discharge coefficients of similarly shaped constructions. The work includes comparison of the flood bags with commonly used bags. Furthermore, the data obtained by measuring and processed in the tabular and graphical form are presented in the work.
|
|
|
Evaluation of Selected Software Tools for Modeling the Leakage of Hazardous Substances in Accidents in the Chemical Industry
Hrušková, Veronika ; Martincová, Jana Victoria (referee) ; Adamec, Vladimír (advisor)
The thesis is aimed at the modeling of releases of hazardous substances to the designated software tools. The work consists of three parts. The first part is theoretical, which deals with hazardous substances and their legislation, accidents in industry, physical models of leakage and dispersion of hazardous substances and factors influencing their spread in the air and finally software tools. The second part, experimental, describes some software tools and their subsequent modeling. The third part is devoted to the results of modeling and analysis of selected software tools. The aim of the thesis is to analyze selected software tools for modeling the release of hazardous substances, to compare their explanatory power and potential use.
|
|
|
The design of the small water reservoir
Galuška, Martin ; Hyánková, Eva (referee) ; Doležal, Petr (advisor)
The concept of this work is to assess options of a small water reservoir design on the selected area Bezměrov. Part of the work refers to different types and functions of small dams and their water management solutions. There is a geological survey presented which is describing the composition of the soil layers and investigating available materials for dam constructions. Water balance has been processed for considered dam profiles evaluating specific outflow of the catchment area, vapor and leakage through a simplified design of the dam. That creates a basic conception about possibilities of water manipulation in this area. Based on this evaluation there are several options processed to explore the retention effects of this two small water reservoirs system above Bezmerov locality.
|
|
|
Influence of degasing on casting quality by high pressure casting
Míšek, Jakub ; Kolmačka, Marek (referee) ; Roučka, Jaromír (advisor)
This thesis examines the influence of the degassing process on hydrogen contend and on the quality of part casted by high pressure casting technologies. The type of defects occurring in the casting is analyzed based on macrostructure and microstructure observations. For the overall assessment is used the statistical observation of the evolution trend of scrapping during the experiment. The results show that shortening of the degassing time may affect the incidence of porosity defect.
|
|
|
New Conceptions of Power Pulse Converters Using Extremely Fast Switching Semiconductors Based on SiC
Kuzdas, Jan ; Chlebiš,, Petr (referee) ; Drábek,, Pavel (referee) ; Vorel, Pavel (advisor)
This work deals with high power pulse converters (tens of kW) using new semiconductor devices of silicon carbide (SiC). Firstly the current state of the issue is analyzed. A research in a specific area of high power buck converters with pulse transformer follows. There was a strong emphasis on minimizing size and weight. The design process was focused also on reliability and robustness. To achieve the defined objectives, it was necessary to use the latest available switching transistors and diodes, and an unusually high switching frequency (100 kHz at a power of about 16 kW). Due to the high switching frequency, we achieved small size of pulse transformers and output chokes. An optimization of high-frequency pulse transformer with demand on minimum volume and weight of core and windings represents a separate theoretical part of the thesis. There have been proposed several analytical solutions of optimization problems, the results of which could overlap with the implementation in practice of switching power supplies. The combination of high switching frequency, fast semiconductors and the high power brings various parasitic effects to the power circuit. In the thesis, these parasitic effects are analyzed. Solutions which minimize or completely remove those effects were theoretically designed and successfully implemented, tested and finalized in experimental part of the work. Detailed description of the implementation of functional sample and series of validation measurements are included in the final part.
|
|
|
Tightness measurement of hermetic compartments in NPP
Sklenár, Ondrej ; Martinec, Jiří (referee) ; Šen, Hugo (advisor)
This diploma thesis deals with measuring the tightness of the hermetic area of nuclear power plant in the way of improving safety. Describes the layout and function of this area - the primary circuit of NPP with WWER 440/213 reactors, as well as methodology for leakage search and leakage calculation procedures. Personal contribution to the issue is a proposal improving tightness of the current state in hermetic area of NPP Jaslovské Bohunice – transition of jacketed pipe designed to collect water from the floor in the box of the steam generator to the heat exchanger of the shower system. This system belongs to the safety system designed to reduce pressure in the LOCA type of accident.
|
|
|
Analysis of sublimit sources of danger from the viewpoint of prevention of serious accidents in the Czech Republic.
FUNJEKOVÁ, Kristýna
The bachelor thesis is Analysis of sub-limit sources of hazards in terms of major accidents prevention in the Czech Republic. It deals with the issue of unclassified hazards sources that do not fall within the scope of Act no. 224/2015 Coll., on major accidents caused by selected hazardous substances or chemical mixtures. The aim of the thesis is to describe the characteristics of lower-tier establishments with hazardous substances and to evaluate the sources of hazards within the lower-tier establishments and beyond the lower-tier establishments.The bachelor thesis is divided into two parts. In the theoretical part, attention is paid to scientific literature, relevant legislation and documentation regulating the issue of unclassified sources of hazards. The research part focuses on the analysis of the sub-limit sources of hazards structure in the individual Czech Republic regions and deals with the current approach of the regional fire rescue services to this issue in order to answer the research questions and the achieved objectives of the thesis. A SWOT analysis has been carried out in order to evaluate the sub-limit sources of hazard in the individual regions in relation to the number of inhabitants of the region as well as the current approach to solving the issue of the lower-tier establishments by the regional fire rescue services. At the conclusion of the thesis, changes for the regional fire rescue services concerning the minimization of hazards represented by the lower-tier establishments are proposed.
|
|
|
The Effect of Angle of Attack on a Blade Cascade with Overlap
Procházka, Pavel P. ; Uruba, Václav ; Pešek, Luděk
This experimental study was carried out to study an aeroelastic coupling in the case of a blade cascade with overlap exposed to tunnel freestream of different angle of attack (AoA). Three of five blades were constructed to allow vertical position changing by the effect of three shakers. Particle Image Velocimetry was used to measure averaged velocity and dynamical parameters of the flow. Mainly, the effect of AoA will be discussed as well as the influence of blade enlargement and Re number. The influence of potential endplates will be indicated.
|
|
|
Influence of degasing on casting quality by high pressure casting
Míšek, Jakub ; Kolmačka, Marek (referee) ; Roučka, Jaromír (advisor)
This thesis examines the influence of the degassing process on hydrogen contend and on the quality of part casted by high pressure casting technologies. The type of defects occurring in the casting is analyzed based on macrostructure and microstructure observations. For the overall assessment is used the statistical observation of the evolution trend of scrapping during the experiment. The results show that shortening of the degassing time may affect the incidence of porosity defect.
|
guest ::
