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Assessment of heat exchangers replacement
Kocanda, Tomáš ; Baláš, Marek (referee) ; Milčák, Pavel (advisor)
This thesis addresses the issue of heat dissipation from the oil system, specifically the lubricating oil of a diesel generator at a nuclear power plant. The literature review section introduces diesel generators, describes the heat exchangers used, and provides a detailed explanation of the problem in the context of a nuclear power plant. In the computational section, a verification calculation of the existing shell-and-tube oil cooler is first performed, followed by the design of a new plate heat exchanger according to specified parameters without altering the layout. In the final part of the thesis, an analysis of the new design compared to the existing one is conducted, including an evaluation of the layout.
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Design of a heat exchangers for cooling process gas
Janoušek, Petr ; Baláš, Marek (referee) ; Toman, Filip (advisor)
Heat exchangers are one of the most used devices in the energy industry. This thesis deals with the overall design of heat exchangers according to the required parameters. Its aim is to perform thermal and hydraulic calculation of two different heat exchangers designed for process gas cooling and compare their resulting design. Specifically, the thesis designs shell and tube heat exchangers, where the first one is an exchanger with straight tube and the second one is an exchanger with U-tubes. The first and second chapters are theoretical sections dealing first with the general issue of heat exchangers and then specifically with shell and tube heat exchangers. The complete design of the straight tube heat exchanger is carried out in chapter three, where its modelled form is also presented. The following chapter deals with the design of the second U-tube exchanger. The final chapter copes with the evaluation and comparison of both types.
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Feedwater heater design
Holčapek, Josef ; Tomáš,, Zdeněk (referee) ; Skála, Zdeněk (advisor)
This diploma thesis deals with the design of a feedwater heater. The aim of the work is to perform thermal, hydraulic and stress analysis. A preliminary technical documentation is also part of this work. The first part contains a summary of basic types of heat exchangers and processes of heat transfer. The main part is focused on thermal analysis to determine the main parameters of the heat exchanger. Next part is followed up by hydraulic analysis to determine the pressure drop of the heating water. After that is created design of heat exchanger with stress analysis of the proposed wall thicknesses of the shell, water chambers and tubesheet. Achieved results are summarized and evaluated at the end of the diploma thesis.
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Truck oil cooler
Pobořil, Martin ; Krištof, Ondřej (referee) ; Bartuli, Erik (advisor)
This diploma thesis deals with designing, fabrication and testing of transmission oil cooler of a truck made of polymeric hollow fibers. Literary research was done in the field of currently used vehicle gearboxes. An overview of properties and a distribution of oils was presented. Oils perform mainly lubricating, hydraulic and cooling function in the gearbox. The thesis contains a design of a cooler according to the specified parameters and its manufacturing process which was done by fiber winding technology. The device X-Winder was used. The program controlling all movements of the machine was programmed. The manufactured cooler passed tear tests and a measurement of characteristic parameters was taken. The pressure drop in fibers was measured at 80 °C . The aim of measurement at 60 and 70 °C was to get a pressure drop in shell and a thermal performance of the cooler. It was found out that the pressure drop dependence on a the shell flow is almost identical for both temperatures, which implies that the effect of the temperature on the pressure drop is negligible. The measurement of thermal performance was done under the same conditions as the measurement of the shell pressure drop. Its maximum achieved reading was 4,8 kW, at shell flow 100 liters per hour and at the temperature 59 °C. The achieved thermal performance is comparable to the thermal performance of standard metal coolers.
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Tubesheet analysis according standards and FEM
Horniak, Patrik ; Vincour, Dušan (referee) ; Pernica, Marek (advisor)
The focus of this master’s thesis is strength design of tube sheet, which is part of shell and tube heat exchanger, with fixed tube sheets. This tube sheet is integrated with both shell and channel of the heat exchanger. First part of the thesis is focused on literature review of shell and tube heat exchangers, tube sheets and calculation standards, which are used for their strength design. The strength design of tube sheet is presented in second part of the thesis, according to the standards: ČSN EN 13445, ASME BPVC VIII and TEMA, along with comparison of these standards. Last section of the thesis deals with the implementation of FEM analysis and its comparison to the analytic approach of strength design, used in accordance to the standards mentioned above.
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Aspects of tubular heat exchangers modeling using available software tools
Ondriašová, Patricie ; Kilkovský, Bohuslav (referee) ; Jegla, Zdeněk (advisor)
The proposed master´s thesis looks into the aspects of tubular heat exchangers modeling using available software tools. In the first – theoretical part there is a description of distribution and types of heat exchangers, including a detailed description of the industrial heat exchanger solved in this thesis. Another chapter is devoted to the main computational relations and calculation methods used in the context of thermo-hydraulic calculation. The main part of thesis consists of chapters, which are devoted to selected available software and perform calculations using the software in the specific industrial case. Finally, there is summary of the various software and a recommendation for the specific program for the need.
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Heat transfer in the tubular exchangers
Horvát, Petr ; Krištof, Ondřej (referee) ; Svěrák, Tomáš (advisor)
Shell and tube heat exchangers and their use in cooling processes are the major topic of this thesis. The theoretical part of the thesis starts with the mechanisms of heat transfer and then deals with shell and tube heat exchangers. Their position, design specifications and equations for calculations are given. In the experimental part, the heat transfer on semi-operating shell and tube heat exchangers with baffles and glass or silicon carbide heat exchange surface is examined by cooling the humid air by 50% propylene glycol in tubes. For four or five coolant flows and three airflows, input and output flow temperatures including relative air humidity were measured. Differences in exchanged heat between the exchangers were negligible due to the low local air heat transfer coefficient, although silicon carbide has two orders of magnitude better thermal conductivity than glass. Much higher efficiency was performed by the carbide heat exchanger because the difference between air outlet temperature and liquid inlet temperature was one and half times higher for the glass heat exchanger. That was reflected in a decrease in mean temperature difference, which resulted in a 16 % higher experimental heat transfer coefficient compared with the glass surface. The theoretical model using the j factor, the correction factors for the baffles, and the correction for air humidity condensation have proven to be appropriate. For the glass surface, for the highest air flow rates the model gives an appropriate heat-transfer coefficient; at lower flow rates it gives slightly higher values. For the silicon carbide surface, it gives a lower heat-transfer coefficient because the model failed to consider a lower mean temperature difference. The results also evaluate the heat loss through the shell and the heat exchanged in addition by air humidity condensation.
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Design of heat exchangers for high temperature applications
Jonák, Martin ; Kilkovský, Bohuslav (referee) ; Kermes, Vít (advisor)
This thesis is devoted to thermal-hydraulic design and rating of heat exchangers with the specialized commercial software HTRI. These heat exchangers are solved for real high-temperature applications, where the hot fluid is a flue gas with high temperature (above 500 °C). In the thesis is made a brief analysis of the conventional design of heat exchangers usable for high-temperature aplications, description of the basic relations, description and brief user manual of software HTRI. Further, work includes a comparative study of methods for calculation of pressure drop of the fluid at 180° elbows, as support analysis for solution of required applications characterized by low pressure drop of process fluids.
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Calculation algorithms for thermal-hydraulic design and rating of unconventional heat transfer equipment
Mikeška, Petr ; Kohoutek, Josef (referee) ; Jegla, Zdeněk (advisor)
The aim of diploma thesis is creating calculation algorithms off single types unconventional heat transfer equipment and their aplication in thermal - hydraulic calculations in the industrial aplication . The main attention is paid to shell and tube heat exchangers with ROD and disc baffle system and radiation heat exchanger. All of these exchangers are used mainly in process of waste thermic destruction. The theoretical part of the work describes construction details of each heat exchanger and calculation algorithms of these equipments. The practical part of the work applies theoretic calculation alghortims in the industrial aplication which is design and rating. In the final part advantages and disadvantages of results have been assessed for construction and process aspects.
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Intermediate heat exchanger natrium - natrium
Kupčík, Petr ; Martinec, Jiří (referee) ; Šen, Hugo (advisor)
This paper deals with intermediate heat exchangers in nuclear power plants. First section of this paper is devoted to analysis and divide of construction designs of intermediate heat exchangers in commercial and experimental power plants. There is a description of thermal, hydraulic and strength calculations during projection of IHX in the second chapter. There has been made a blueprint of loop type IHX in the final chapter of this paper.
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