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Design of heat exchanger for heating and humidification of combustion air
Pollach, Ondřej ; Lisý, Martin (referee) ; Baláš, Marek (advisor)
The diploma thesis‘ goal is to design shell and tube combustion air preheater for biomass boiler. The diploma thesis also includes the research of the effect of flue gas condensation on boilers power increase. The first part of the diploma thesis is theoretical introduction about types of air preheaters, options of air moisturing and effect of flue gas condensation on boiler. Following part describes the thermal calculations and construction design of air preheater as well as the condensing flue gas power increase and power increase due to humidification of combustion air.
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Replacement of existing heat exchanger
Vaculík, Štěpán ; Toman, Filip (referee) ; Baláš, Marek (advisor)
This thesis deals with the possibilities of replacing an existing inefficient heat exchanger with a new one. In the first theoretical part a research of heat exchanger types, their operational features and suitable application is carried out. In the second practical part, the control calculation of the existing bundle heat exchanger with U-tubes is performed first, followed by the thermo-hydraulic design of a new bundle heat exchanger with straight tubes and a new plate heat exchanger. In the last part of the work, a comparison and assessment of which of the alternatives is the most suitable is made.
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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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Design of heat exchanger for heating and humidification of combustion air
Pollach, Ondřej ; Lisý, Martin (referee) ; Baláš, Marek (advisor)
The diploma thesis‘ goal is to design shell and tube combustion air preheater for biomass boiler. The diploma thesis also includes the research of the effect of flue gas condensation on boilers power increase. The first part of the diploma thesis is theoretical introduction about types of air preheaters, options of air moisturing and effect of flue gas condensation on boiler. Following part describes the thermal calculations and construction design of air preheater as well as the condensing flue gas power increase and power increase due to humidification of combustion air.
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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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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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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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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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Software Aided Design and Assessment of Shell and Tube Heat Exchangers
Létal, Tomáš ; Klemeš,, Jiří (referee) ; Vincour, Dušan (referee) ; Jegla, Zdeněk (advisor)
Subject of this work is a development of an integrated software environment for mechanical design and check of shell and tube heat exchangers. Processes of mechanical design and checks well as software which perform these processes are broken down to basic methods and parts. Mechanical design is usually performed according to some standards. In this work, ČSN EN 13445 is used. This standard describes mostly design check calculations which can be easily algorithmized. On the contrary, design calculations are described to some extent in few simple cases and mechanical design of shell and tube heat exchanger has not been fully algorithmized yet. Subject of this work is design of software, which will be capable of automatically performing mechanical design from datasheet as an input. Based on breakdown of design and check processes, requirements for key software features are derived. Important part of presented work is design and implementation of key modules – data model of shell and tube heat exchanger, module for mechanical design check according to ČSN EN 13445. These modules form basis of the software which will be developed further in future work.
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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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