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Evaluation of the alternatives of PCDD/F removing in the incineration plants
Frýba, Lukáš ; Kropáč, Jiří (referee) ; Bébar, Ladislav (advisor)
The thesis is focused on analyzing the current status of the technology used for cleaning flue gas from persistent organic pollutants, especially PCDD/F. For the three most commonly used methods of solution operational and energy efficiency comparison was made, where achievable energy export and the impact of the change in working conditions on the efficiency indicators of energy production and use of the energy was evaluated. In conditions we considered an alternative machine-technological solutions used for the final disposal of persistent organic pollutants resulting from the waste combustion in terms of additional operating costs and energy efficiency.
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Evaluation of particle deposition rate in cement plant ductwork
Dorniak, Michal ; Kilkovský, Bohuslav (referee) ; Vondál, Jiří (advisor)
The submitted thesis deals with calculation of pressure drop in pipeline of cement industry, which is directly correlated with energy consumption of raw mill exhaust fans. The introduction in submitted thesis describes theoretical basics of cement production. Part of theoretical analysis is about detailed study of calculations of different friction factors. Separately for gas and separately for solids. In the practical part, a mathematical model of universal configuration of pipeline for pressure drop calculations was created. The last part evaluate impacts of pressure drop on energetic demands of raw mill exhaust fans.
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Study of the Gas Blow-by through the Turbocharger Sealing System
Požár, Vladimír ; Novotný, Pavel (referee) ; Vacula, Jiří (advisor)
The work focuses on the investigation of gas flow within the sealing system of a turbocharger, specifically in the compressor section. The sealing „piston” ring located here is the main subject of the study, primarily examining the influence of the ring's geometry and its positioning in the shaft groove on gas leakage into the bearing housing. Furthermore, the behavior of this flow under various boundary conditions is assessed by testing different flow types.
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Effect of a Tension on Pressure Drop Across the Flexible Bank of Polymeric Hollow Fibres in Crossflow
Kroulíková, Tereza ; Baláš, Marek (referee) ; Dančová,, Petra (referee) ; Hnízdil, Milan (advisor)
Pressure drop, such as the heat transfer rate, is an important parameter in heat exchanger design. Its values also determine the required pump performance for given medium. Several empirical relationships defined for calculating the pressure drop over a bank of tubes have been preserved from the last century; however, these relationships are based on measurements performed on large rigid tubes, thus, they do not include flexibility of thin fibres, and the pressure drop values calculated by the model might not reflect reality. This dissertation thesis discusses the air-side pressure drop of a bank of hollow polymer fibres, in particular, the effect of the tension in said fibers. Therefore, other possible effects of influence, such as random fiber pitches and fiber length differences, were minimized. A special device was made for tensioning the hollow fibre heat exchanger in order to measure the pressure drop. A set of measurements was performed, and the measured values were analysed and compared to two empirical models. At the end of the thesis, two model proposals for two geometries, namely for heat exchangers with a staggered design and dimensionless pitches of 2x2 and 2x3.
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Evaluation of particle deposition rate in cement plant ductwork
Dorniak, Michal ; Kilkovský, Bohuslav (referee) ; Vondál, Jiří (advisor)
The submitted thesis deals with calculation of pressure drop in pipeline of cement industry, which is directly correlated with energy consumption of raw mill exhaust fans. The introduction in submitted thesis describes theoretical basics of cement production. Part of theoretical analysis is about detailed study of calculations of different friction factors. Separately for gas and separately for solids. In the practical part, a mathematical model of universal configuration of pipeline for pressure drop calculations was created. The last part evaluate impacts of pressure drop on energetic demands of raw mill exhaust fans.
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Experimental support for the development of specific integrated equipment
Hrbáček, Jiří ; Jegla, Zdeněk (referee) ; Kilkovský, Bohuslav (advisor)
Regenerative heat exchangers are used in a wide range of industries and in the technical equipment of buildings. These heat exchangers play an important role in saving thermal energy and removing volatile organic compounds from flue gases. The theoretical part of the work deals with the division of regenerative exchangers into rotary and switching exchangers and the possibilities of their use. These types of heat exchangers are used in many applications, e.g. as a heat exchanger using waste heat to preheat the process gas (regeneration layer), or as catalysts to accelerate the reaction required to remove volatile organic compounds (catalytic layer), or as integrated equipment where both the regeneration layer and the catalytic layer. The aim of the diploma thesis is experimental support in the development of a computer program for the design of a specific integrated device. The program allows the calculation of the regeneration and catalytic bed, or both beds simultaneously, i.e. integrated equipment. The diploma thesis deals with the support of a mathematical model for the calculation of the regeneration bed. Pressure loss and heat transfer play an important role in the selection and subsequent calculation of a suitable bed. To calculate them, it is possible to find more available computational relationships that differ significantly in their accuracy. It is therefore necessary to select the most suitable ones for the computational model. The practical part of the work then deals with research, analysis, and assessment of the suitability of methods used to calculate pressure losses based on a comparison with the values measured on experimental equipment. Subsequently, the work deals with computational methods for determining the heat transfer coefficient of the packed bed. A significant part of the practical part deals with the modification of the experimental equipment for the verification of computational relations for the determination of heat transfer with measured data.
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Heat transfer design
Murín, Milan ; Brázdil, Marian (referee) ; Špiláček, Michal (advisor)
The bachelor thesis deals with a design of water – water heat exchanger with two types of baffle systems, disk and doughnut, and segmental. The thesis contains classification and description of tubular heat exchangers, geometry design, and calculation of pressure drops and heat transfer of the device for both eventualities. It also contains construction drawings of both types of baffles.
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Effect of exchanger fouling and heat transfer coefficient
Konopiský, Karel ; Kracík, Petr (referee) ; Baláš, Marek (advisor)
This diploma thesis covers the influence of fouling in heat exchangers and heat transfer coefficient. In the first part of the thesis are covered the characteristics of fouling and its formation, process, and effects on heat transfer surfaces in exchangers. In the next part of the thesis, chemical analysis of cooling water is performed on an extracted sample and the potential of fouling is determined based on the analysis. In the conclusion part, computational models of fouling in the tube side of the heat exchanger are presented; fouling of an actual heat exchanger is calculated and compared with data captured during the operation of the heat exchanger.
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Modern technological elements for tubular heat exchangers
Plánková, Tereza ; Babička Fialová, Dominika (referee) ; Jegla, Zdeněk (advisor)
The aim of this diploma thesis is to get acquainted with modern technological elements currently used in shell-and-tube heat exchanger in the shell-side and tube-side, thermal-hydraulic calculation of selected elements and comparison of thermal-hydraulic properties with classically used competing technological elements. The work deals mainly with EM baffle in the tube-side and tube inserts like the twisted tape type (and its modifications) and coiled wire in the tube-side. The theoretical part is focused on acquaintance with classical technological elements in shell-and-tube heat exchanger and with basic thermal-hydraulic calculations, practical part then on acquaintance with modern elements and thermal-hydraulic calculation of selected elements. These calculations are then compared with the results of the thermo-hydraulic calculation of similar elements.
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Application of Polymeric Hollow-Fiber Membranes in Air Filtration
Bulejko, Pavel ; Dohnal, Mirko (referee) ; Friess, Karel (referee) ; Svěrák, Tomáš (advisor)
Membrány z dutých vláken jsou široce využívány v aplikacích týkajících se úpravy kapalin jako např. při čištění odpadních vod, v membránových kontaktorech a bioreaktorech, membránové destilaci apod. I když jsou často využívány při separacích směsí plynů, je jejich použití pro mechanickou filtraci aerosolů velmi vzácné. Tato práce se zabývá filtrací vzduchu pomocí polypropylenových membrán z dutých vláken včetně jejich filtrační účinnosti, tlakových ztrát a také zanášením při dlouhodobé filtraci. Filtrační účinnost byla proměřena za použití různých aerosolů jako TiO2 a síran amonný. Tlakové ztráty byly měřeny při různých konfiguracích, tj. různé filtrační ploše a průměru vlákna membrány. Zanášení membrán bylo testováno použitím normovaného prachu definovaného normou ANSI/ASHRAE 52.2. Predikční modely pro filtrační účinnost a permeabilitu/tlakovou ztrátu membrány byly aplikovány na parametry membrán z dutých vláken a porovnány. Tyto membrány mají velikost pórů kolem 90 nm a poměrně nízkou porositu a tím vysoký potenciál pro separaci nanočástic ze vzduchu. Dále byla provedena analýza filtračního koláče a vyhodnocení energetických nároků a porovnány s teoretickými modely. V závěru práce je nastíněn odhad ceny životního cyklu při filtraci pomocí těchto membrán.
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