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Study of Thermal Properties of Materials
Štefková, Pavla ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The doctoral thesis deals with study of thermal properties of materials. Behavior of homogeneous matters at different temperatures is well described in theory and experimentally verified. Overall effect of all components of mixture and other influences related with material creation affect behaviour and properties of heterogeneous matters. For study of thermal properties can be used transient method of measurement which provide a picture about overall influence of all components of mixture on studied heterogeneous material and among others enable determination of thermophysical properties of whole macroscopic system in observed temperature range. Properties of solid matters, thin foil and liquids can be measured by means of pulse and step-wise transient method which is used for experimental activity in the thesis. It is contact measurement method and its principle is based on small quantity of heat generating inside the specimen and temperature response measuring. Theoretical part of thesis is focused on creation of method for determination of thermophysical parameters. The base is differential equation of the heat conduction. Its solution is temperature function. Three methods of evaluation are described mathematically. They start from general relations designed for study of fractal structure physical properties (maximum of function method, differential method and multi-parametric non-linear regression method).
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Optimalisation of thermal properties of solar cell modules
Dohnalová, Lenka ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of presented diploma thesis is study of thermal properties structures of photovoltaic cells. The main goal of this thesis is study of ways of heat spreading from volume and planar materials (conduction, convection and radiation). Then it is needed to determine contributions of heat spread from laminated photovoltaic cell and compare them to results measured by transient pulse method, step wise method and with thermo-camera using. At the beginning of this thesis it will be needed to define heat and ways it’s spread. Heat is closely connected with temperature. That is reason why will be there spoken about temperature and methods of its measuring. Than there will be defined basic thermo-physical parameters of materials. Thermo-physical parameters of materials will be measured by transient methods that will be characterized later and by thermo-camera. This thesis deals with photovoltaic cells, so there will be described their structure, properties, utilization and way of their production. Subsequently after the definition of all needed terms the experimental part of this thesis will be introduced. It will be needed to characterize measured volume material and define its thermo-physical parameters. Using the pulse transient method, step wise method and thermo-camera there will be measured the thermal response of PMMA sample, nonlaminated photovoltaic cell and also samples of laminated photovoltaic cells. Findings of all described methods will be finally compared.
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Study of Electric and Dielectric Properties of Alkali-Activated Aluminosilicate with Increased Electrical Conductivity
Florián, Pavel ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
This dissertation deals with the study of electric and dielectric properties of composite structures on the base of alkali-activated aluminosilicates with admixtures of various carbon particles. These materials fabricated from alkali-activated blast furnace slag, quarz sand, natrium water glass as alkali activator, water, dispersant and small amount of carbon admixture (carbon black, graphite powder, carbon fibers or carbon nanotubes) to increase electric conductivity may be used for example to construction of snow-melting, deicing and self-monitoring systems. Their current-voltage characteristics and impedance spectra were used for determination of electric and dielectric properties of these structures. The equivalent circuits were used for evaluation of impedance spectra. The results were correlated with thermal properties of these structures.
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Study of thermal properties of materials for solar cells lamination
Dohnalová, Lenka ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of presented bachelor´s thesis was study of thermal properties of materials for solar cells lamination. The main goal of this thesis was measuring and characterisation of the basic thermal properties of volume materials and plastic films, which are used to solar cells lamination. At first a thermal response to a concrete thermal pulse was measured by the thermoelectric thermometer. Then there was studied the distribution of temperature on the surface of a sample during heating and cooling by the non-point heat source. At the beggining of this thesis it was needed to define heat and ways it´s spread, then the basic thermal properties and also methods of their determination. The ways of measuring temperature were described and then used in praxis. My thesis deals with study of thermal properties volume materials. It was needed to characterize measured volume material and define it´s thermal parameters, because the values of thermal parameters of measured samples of lamination films were compared to these values. This thesis is concerned in solar cells too. So there were also described their structure, properties, utilization and way of their production. After the definition of all needed therms the experimental part of this thesis was begun. At first the thermal response of each of the eight different samples was measured by the pulse transient method. Then there was studied the thermal field on the surface of the sample by thermocamera through using the pulse transient method. Findings of both methods were finally compared.
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Study of Thermal Properties of Materials for Cooling of Photovoltaic Panels
Dohnalová, Lenka ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of this doctoral thesis is to study the thermal properties of PCM materials and discussion of their use for cooling of photovoltaic systems. The aim of the study is to measure and characterize the thermal properties of commercial PCM materials (Micronal®), their practical use is related to the phase transitions. The behavior of bulk materials at different temperatures is well described theoretically and experimentally verified. For the application use it is necessary to examine and determine the thermal properties of PCM materials depending on the phase transitions during heating and cooling. To study the thermal properties of materials the known transient methods of measuring are used which give full information about the behavior of the materials investigated in dependence on the temperature and thus allow the determination of the thermo-physical parameters of the system. For the transient measurements there are used especially pulse transient and step wise method. Newly is used also combination of linear temperature rise (the ramp wise) and the step wise method. The principle is based on the generation of a small amount of heat inside the studied sample and it is measured the thermal response of the system from which it may be then determined the necessary thermo-physical parameters. The theoretical part of this thesis focuses on characterization of methods for the determination of thermo-physical parameters of the investigated material. In the experimental part of the approached process of experiment, the results, the method of evaluation of the obtained data and also the discussion of results from the viewpoint of potential applications are presented.
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Study of Electric and Dielectric Properties of Alkali-Activated Aluminosilicate with Increased Electrical Conductivity
Florián, Pavel ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
This dissertation deals with the study of electric and dielectric properties of composite structures on the base of alkali-activated aluminosilicates with admixtures of various carbon particles. These materials fabricated from alkali-activated blast furnace slag, quarz sand, natrium water glass as alkali activator, water, dispersant and small amount of carbon admixture (carbon black, graphite powder, carbon fibers or carbon nanotubes) to increase electric conductivity may be used for example to construction of snow-melting, deicing and self-monitoring systems. Their current-voltage characteristics and impedance spectra were used for determination of electric and dielectric properties of these structures. The equivalent circuits were used for evaluation of impedance spectra. The results were correlated with thermal properties of these structures.
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Study of Thermal Properties of Materials for Cooling of Photovoltaic Panels
Dohnalová, Lenka ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of this doctoral thesis is to study the thermal properties of PCM materials and discussion of their use for cooling of photovoltaic systems. The aim of the study is to measure and characterize the thermal properties of commercial PCM materials (Micronal®), their practical use is related to the phase transitions. The behavior of bulk materials at different temperatures is well described theoretically and experimentally verified. For the application use it is necessary to examine and determine the thermal properties of PCM materials depending on the phase transitions during heating and cooling. To study the thermal properties of materials the known transient methods of measuring are used which give full information about the behavior of the materials investigated in dependence on the temperature and thus allow the determination of the thermo-physical parameters of the system. For the transient measurements there are used especially pulse transient and step wise method. Newly is used also combination of linear temperature rise (the ramp wise) and the step wise method. The principle is based on the generation of a small amount of heat inside the studied sample and it is measured the thermal response of the system from which it may be then determined the necessary thermo-physical parameters. The theoretical part of this thesis focuses on characterization of methods for the determination of thermo-physical parameters of the investigated material. In the experimental part of the approached process of experiment, the results, the method of evaluation of the obtained data and also the discussion of results from the viewpoint of potential applications are presented.
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Study of Thermal Properties of Materials
Štefková, Pavla ; Pavlík, Zbyšek (referee) ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The doctoral thesis deals with study of thermal properties of materials. Behavior of homogeneous matters at different temperatures is well described in theory and experimentally verified. Overall effect of all components of mixture and other influences related with material creation affect behaviour and properties of heterogeneous matters. For study of thermal properties can be used transient method of measurement which provide a picture about overall influence of all components of mixture on studied heterogeneous material and among others enable determination of thermophysical properties of whole macroscopic system in observed temperature range. Properties of solid matters, thin foil and liquids can be measured by means of pulse and step-wise transient method which is used for experimental activity in the thesis. It is contact measurement method and its principle is based on small quantity of heat generating inside the specimen and temperature response measuring. Theoretical part of thesis is focused on creation of method for determination of thermophysical parameters. The base is differential equation of the heat conduction. Its solution is temperature function. Three methods of evaluation are described mathematically. They start from general relations designed for study of fractal structure physical properties (maximum of function method, differential method and multi-parametric non-linear regression method).
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Optimalisation of thermal properties of solar cell modules
Dohnalová, Lenka ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of presented diploma thesis is study of thermal properties structures of photovoltaic cells. The main goal of this thesis is study of ways of heat spreading from volume and planar materials (conduction, convection and radiation). Then it is needed to determine contributions of heat spread from laminated photovoltaic cell and compare them to results measured by transient pulse method, step wise method and with thermo-camera using. At the beginning of this thesis it will be needed to define heat and ways it’s spread. Heat is closely connected with temperature. That is reason why will be there spoken about temperature and methods of its measuring. Than there will be defined basic thermo-physical parameters of materials. Thermo-physical parameters of materials will be measured by transient methods that will be characterized later and by thermo-camera. This thesis deals with photovoltaic cells, so there will be described their structure, properties, utilization and way of their production. Subsequently after the definition of all needed terms the experimental part of this thesis will be introduced. It will be needed to characterize measured volume material and define its thermo-physical parameters. Using the pulse transient method, step wise method and thermo-camera there will be measured the thermal response of PMMA sample, nonlaminated photovoltaic cell and also samples of laminated photovoltaic cells. Findings of all described methods will be finally compared.
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Study of thermal properties of materials for solar cells lamination
Dohnalová, Lenka ; Matiašovský, Peter (referee) ; Zmeškal, Oldřich (advisor)
The topic of presented bachelor´s thesis was study of thermal properties of materials for solar cells lamination. The main goal of this thesis was measuring and characterisation of the basic thermal properties of volume materials and plastic films, which are used to solar cells lamination. At first a thermal response to a concrete thermal pulse was measured by the thermoelectric thermometer. Then there was studied the distribution of temperature on the surface of a sample during heating and cooling by the non-point heat source. At the beggining of this thesis it was needed to define heat and ways it´s spread, then the basic thermal properties and also methods of their determination. The ways of measuring temperature were described and then used in praxis. My thesis deals with study of thermal properties volume materials. It was needed to characterize measured volume material and define it´s thermal parameters, because the values of thermal parameters of measured samples of lamination films were compared to these values. This thesis is concerned in solar cells too. So there were also described their structure, properties, utilization and way of their production. After the definition of all needed therms the experimental part of this thesis was begun. At first the thermal response of each of the eight different samples was measured by the pulse transient method. Then there was studied the thermal field on the surface of the sample by thermocamera through using the pulse transient method. Findings of both methods were finally compared.
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