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Influenc of Instability to Critical Heat Flux
Khůlová, Jitka ; Vojáčková, Jitka (referee) ; Suk, Ladislav (advisor)
This bachelor's thesis is elaborating about two-phase flow in the heated channel. It describes flow instabilities and their influence to critical heat flux. The calculation methods of two-phase flow are introduced. The homogeneous equilibrium method is selected for the practical part. The results are evaluated and possible solution to prevent flow instabilities is suggested.
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Flow in a bypass of a waterfeed valve
Waloszek, Jan ; Dohnal, Miloslav (referee) ; Juřena, Tomáš (advisor)
Fluid flow in pipes and fittings has a significant meaning in many sectors of industrial applications and thus it is important to reduce hydraulic ressistance in order to reduce pressure loses and ensure better efficiency of the system. In this thesis flow through two types of fitting is solved, using computer simulation. Empirical equations are used to verify results and to set the computer model right. This thesis formulates several conclusions in relation to k- turbulence model and accuracy of the results related to discretisation of the mesh.
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Numerical modeling of the water cooled charge air cooler in/out chamber leading to development of the analytical model
Lasota, Martin ; Pavlica, Ondřej (referee) ; Pokorný, Jan (advisor)
Diploma thesis deals with numerical simulations of an air flow in a water cooled charge air cooler (WCAC), specifically with pressure drops in inlet/outlet chamber. The simulations have been performed in a proprietary software Star-CCM+. Physical phenomena have been solved by the Reynolds-averaged Navier-Stokes (RANS) equations and consequently a matrix of pressure drops for miscellaneous variations of chamber's geometry and the initial flow conditions has been created. Based on the CFD results, dependence between calculated pressure drops and changing parameters has been analyzed and finally a 1D solver has been developed and implemented into a software OpenModelica.
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Proposal of horizontal dual-pressure heat recovery steam generator
Slíva, Karel ; Svoboda, Petr (referee) ; Baláš, Marek (advisor)
The focus of this thesis is a proposal of a horizontal dual-pressure heat recovery steam generator. The introductory part includes thermal calculation, as well as a design of the layout and a design of the heat transfer surfaces and the layout of the boiler. Individual chapters are broken down according to the outline of the proposal for the arrangement of the heating surfaces, according to the parameters of the flue gas and steam. The master thesis contains a scheme of a real heat transfer temperature diagram and it also includes the calculation of connecting and downcomer pipes and drums. The final part describes the calculation of the boiler draft loss. The main idea of the thesis is accompanied by the technical documentation of the drawing of the boiler.
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Theoretical use of nanotechnology for filtration in HVAC systems
Bosák, Jan ; Ell, Jiří (referee) ; Rubina, Aleš (advisor)
Thesis solves problems using the nanotechnology for air filtration in HVAC systems. Main specialization work is air filtration for clean spaces with high classes of purity. For example Hospitals, sophisticated technology service, pharmacy etc. Thesis is devide for three parts. First part contains foundation infromations about theory and making fabrics by nanotechnology. Next I described laws of physics, That were using during the solving filtration´s issues. Goal for second part was making the experiments, which should show abilities and properties nanofilters during the air filtration in real environment HVAC systems. In the end measure part is compare nanofilters with common filters. There is describe nanofiltres behavior and their possibilies during the filtration as well as. In last part I expressed own opinions on air filtration by nanofibers. Opinions were making throught informations, That I found out in the process working on thesis and my experiences in HVAC field. By this facts I did compare for get a better idea. Additionally last part contains summary infomations from previously parts and own vision to development in the future. Goal work isn´t promotion and advertising sorts technologies. Ask is just summary and describe discovered knowledges, considered opinions ensue from measuring, information from the Net and people Who work in nanotechnology field.
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Absorption Cleaning of Flue Gases Arising from the Incineration of Wastes
Jecha, David ; Klemeš,, Jiří (referee) ; Žaloudík, Petr (referee) ; Bébar, Ladislav (advisor)
This doctoral thesis deals with potentials of methods for cleaning of flue gas from pollutants such as acidic components. Wet method of flue gas cleaning is analysed in detail with special focus on elimination of sulphur dioxide (SO2). Introduction presents advantages and disadvantages of thermal processing of waste and production of undesired pollutants. Following parts comprise facts about main pollutants produced from incineration. Legislation providing for emission of gaseous pollutants from incinerators is also given. Chapter concerning methods of pollutants elimination is mostly focused on absorption (wet and/or semidry scrubber) and adsorption methods. Several up-to-date technological procedures are mentioned; they have a multifunctional effect such as elimination of acidic components, heavy metals, polychlorinated dibenzo-p-dioxines and dibenzo-furanes from flue gas using single injection of suspense. Elimination of mercury (Hg) is among the technologies for heavy metal elimination which is described in detail. Main part of the thesis is related to experiments at two-stage flue gas cleaning equipment. Function of this experimental unit is described along with methods for measurement of individual quantities and detailed description of all the equipment and its components. Experimental measurements carried out at this equipment are explicated and assessed. Along with experimental work, the author has created a simulation model of wet flue gas cleaning in ChemCad programme. Particular operational parameters were tested on this model. This thesis contains results of the measurement which provide background for verification of the mathematical model. Further, the balance of heavy metals conducted on the basis of measurements in waste incinerator is displayed. Main contribution of the thesis may be summed up as follows: Author has designed and constructed experimental equipment for two stage flue gas cleaning. He also formed calculation for pressure drop of O-element prototype equipment and for packing column with FLEXIPAC structured packing. He created data file with measurements at the experimental unit. He determined temperature at outlet of a random device where liquid is injected into stream of hot flue gas. He designed a simulation model which is identical with experimental equipment and which usage enabled comparison of measured and calculated data; it also serves as a basis for industrial applications. Last part deals with creation off heavy metals balance in a case industrial waste incinerator.
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Design and optimization of the control valve for EHRS exchanger
Rada, Jakub ; Svída, David (referee) ; Beran, Martin (advisor)
This diploma thesis deals with the design and optimization of the control valve for EHRS exchanger. The first part of the thesis contains a research describing the historical development of internal combustion engines, their impact on the environment and especially the possible ways of waste heat recovery. The second part focuses on the design of the control valve and experimental measurement to verify its functionality. The final part contains an analysis of pressure losses of the designed valve to improve its construction disadvantages.
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Ventilation and heating in a single family house
Sláčík, Ondřej ; Lízal, František (referee) ; Charvát, Pavel (advisor)
This master’s thesis deals with the design of the ventilation and heating system in low-energy single family house. The thesis is divided into three parts. The first part of the thesis provides an overview of the project together with the requirements of the house owner. The options for heating and ventilation in low-energy buildings are also discussed in this part. The second part deals with the design of the ventilation system with heat recovery. The design includes determination of the amount of ventilation air, selection of a suitable ventilation unit and the design of the supply air and return air ductworks. The last part focuses on the heating system. It includes the calculations of the heat loss of the house and design of floor heating. Furthermore, the selection of heat source together with the safety measures is described in this part. Both design parts include the bills of materials, along with the budget and the drawings.
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Cleaning of biogas by the PSA (pressure swing adsorption)
Navrátil, Petr ; Houdková, Lucie (referee) ; Leštinský, Pavel (advisor)
The topic of this master thesis is upgrading of biogas. As a mixture of gases produced during anaerobic digestion, contains methane which is highly energy valuable gas. But also other substances that we want to remove. We will present the motivation for upgrading biogas and the possibility of separation, generally the pressure swing adsorption method. The key parameter of this technique is the choice of a suitable adsorbent. This is possible based on the knowledge of adsorption processes, therefore, is also described below. The objective of this thesis is to determine the parameters of the pressure swing adsorption metod. To do this it is necessary to determine the adsorption capacity of the adsorbent, measure breakthrough curves of carbon dioxide and methane, and determine the pressure drop of solid bed, etc. As a result we can finally make a balance and evaluate the applicability in practice.
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Design of a space heating system and hot water heating for family guest-house
Nykl, František ; Pech, Ondřej (referee) ; Katolický, Jaroslav (advisor)
This diploma thesis describes the detailed design of heating and hot water heating for a family quest-house. At first the reader is introduced to the designed building, its design and construction elements. The thesis presents the calculation procedure and design of the heating system. This consists of designing radiators, the heat source, the circulating pumps, regulations of the heating system and the design of its security elements. The thesis also describes the design of the heat exchanger for hot water and security. In conclusion, an evaluation of operating costs with the recommended solution for their reduction. The thesis also includes drawing documentation of structural drawings, heating and unrolled schema that is mentioned in the attachment.
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