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Experimental thermocamera measurements
Jakl, Oldřich ; Číp, Pavel (referee) ; Petyovský, Petr (advisor)
This work is focused on the features and the principles of the measuring of the thermovision cameras. There is the identification of the basic notions and physical laws on which is based the operation of the thermovision cameras in the first part of my work. In the second part there is describtion of the function of the detectors of infrared radiation and the character of the output data of the thermovision camera. Further there are presented the experiments and the observations which bring us closer to the features of the thermovision cameras and help us interpret the data gained by camera.
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Measuring of emissivity of wet and dry surfaces
Brzobohatý, Tomáš ; Janotková, Eva (referee) ; Pavelek, Milan (advisor)
The objective of this thesis is to create summary of emissivity of wet surfaces, emissivity of rime surfaces and emissivity of dry surfaces. The next objective is to create materials for termovision measurement and find the use for this materials for practice. Theoretical part of thesis deals with a theory of ways of heat transfer (radiation mainly), description of emisivity concept, description of emisivity finding ways and the show emissivity of mesuared materials from avaible sources for working hypothesis. Emissivity of dry, wet and rime samples were measured as the experimental part of thesis. Experimental part of thesis consist of experiment description, working hypothesis, measuring instruments and measuring area description, measuring proces description and presentation of measured results. Obtained dependences are benefits for termovision measurent, energy evaluation and the thermal state microclimate simulations.
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Heat Transfer Evaluation on Falling Film Tube Bundle
Kracík, Petr ; Masaryk, Michal (referee) ; Kořista, Milan (referee) ; Pospíšil, Jiří (advisor)
Sprinkled tube bundles with a thin liquid film flowing over them are used in various technology processes where it is necessary to separate the vapour and liquid phases quickly and efficiently. The process occurs predominantly at low temperatures with a corresponding decrease of pressure around the tube bundle. Such a technology is represented for instance by an evaporator at absorption units or an evaporator for sea water desalination. In ideal conditions water boils at the whole surface of an exchanger, but in practice it must be considered that in original spots of contact between water and the exchanger wall the water will not boil at the tubes' surface but the cooling liquid will merely be heated-up. The presented dissertation thesis focuses on this issue. The objective of the thesis was to determine the heat transfer coefficient at the surface of sprinkled tube bundles of various geometries at atmospheric pressure as well as low pressure. For this purpose experiments have been carried out at tube bundles consisting of copper tubes of 12,0 mm diameter placed horizontally one above another that were heated by water. Three types of tubes (smooth, sandblasted and grooved) of four various pitches (15,0 to 30,0 mm by 5,0 mm increments) have been tested. Simultaneously individual bundles' geometries consisted of 4, 6, 8 and 10 tubes with identical surface finish. Based on the conducted experiments the mathematical model of heat transfer that involves mainly analogy criteria has been made more accurate. A temperature field at the sprinkled tube bundle surface has been scanned by a thermographic camera during the performed experiments. Influence of geometry and tube surface finish on flow mode and consequently also on heat transfer has been assessed in accordance with the compiled methodology.
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Factors affecting the degradation of photovoltaic power plant
Mačát, Jakub ; Jandová, Kristýna (referee) ; Vaněk, Jiří (advisor)
My diploma thesis focuses in its theoretical part on the analysis of photovoltaic cells, panels, their properties and defects . Further there are described materials from which the cells and panels are produced today but also there are mentioned materials which could affect the near future. There are also state the methods of measurement of photovoltaic cells . The practical part analyzes selected photovoltaic panels, determines the level of degradation by measurement and calculation with using the intensity of solar radiation. All results are entred into graphs and tables.
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Heat Transfer Evaluation on Falling Film Tube Bundle
Kracík, Petr ; Masaryk, Michal (referee) ; Kořista, Milan (referee) ; Pospíšil, Jiří (advisor)
Sprinkled tube bundles with a thin liquid film flowing over them are used in various technology processes where it is necessary to separate the vapour and liquid phases quickly and efficiently. The process occurs predominantly at low temperatures with a corresponding decrease of pressure around the tube bundle. Such a technology is represented for instance by an evaporator at absorption units or an evaporator for sea water desalination. In ideal conditions water boils at the whole surface of an exchanger, but in practice it must be considered that in original spots of contact between water and the exchanger wall the water will not boil at the tubes' surface but the cooling liquid will merely be heated-up. The presented dissertation thesis focuses on this issue. The objective of the thesis was to determine the heat transfer coefficient at the surface of sprinkled tube bundles of various geometries at atmospheric pressure as well as low pressure. For this purpose experiments have been carried out at tube bundles consisting of copper tubes of 12,0 mm diameter placed horizontally one above another that were heated by water. Three types of tubes (smooth, sandblasted and grooved) of four various pitches (15,0 to 30,0 mm by 5,0 mm increments) have been tested. Simultaneously individual bundles' geometries consisted of 4, 6, 8 and 10 tubes with identical surface finish. Based on the conducted experiments the mathematical model of heat transfer that involves mainly analogy criteria has been made more accurate. A temperature field at the sprinkled tube bundle surface has been scanned by a thermographic camera during the performed experiments. Influence of geometry and tube surface finish on flow mode and consequently also on heat transfer has been assessed in accordance with the compiled methodology.
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Experimental thermocamera measurements
Jakl, Oldřich ; Číp, Pavel (referee) ; Petyovský, Petr (advisor)
This work is focused on the features and the principles of the measuring of the thermovision cameras. There is the identification of the basic notions and physical laws on which is based the operation of the thermovision cameras in the first part of my work. In the second part there is describtion of the function of the detectors of infrared radiation and the character of the output data of the thermovision camera. Further there are presented the experiments and the observations which bring us closer to the features of the thermovision cameras and help us interpret the data gained by camera.
|
|
|
Measuring of emissivity of wet and dry surfaces
Brzobohatý, Tomáš ; Janotková, Eva (referee) ; Pavelek, Milan (advisor)
The objective of this thesis is to create summary of emissivity of wet surfaces, emissivity of rime surfaces and emissivity of dry surfaces. The next objective is to create materials for termovision measurement and find the use for this materials for practice. Theoretical part of thesis deals with a theory of ways of heat transfer (radiation mainly), description of emisivity concept, description of emisivity finding ways and the show emissivity of mesuared materials from avaible sources for working hypothesis. Emissivity of dry, wet and rime samples were measured as the experimental part of thesis. Experimental part of thesis consist of experiment description, working hypothesis, measuring instruments and measuring area description, measuring proces description and presentation of measured results. Obtained dependences are benefits for termovision measurent, energy evaluation and the thermal state microclimate simulations.
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Factors affecting the degradation of photovoltaic power plant
Mačát, Jakub ; Jandová, Kristýna (referee) ; Vaněk, Jiří (advisor)
My diploma thesis focuses in its theoretical part on the analysis of photovoltaic cells, panels, their properties and defects . Further there are described materials from which the cells and panels are produced today but also there are mentioned materials which could affect the near future. There are also state the methods of measurement of photovoltaic cells . The practical part analyzes selected photovoltaic panels, determines the level of degradation by measurement and calculation with using the intensity of solar radiation. All results are entred into graphs and tables.
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