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Verification of thermal-insulation properties of the foil materials
Šot, Petr ; TROJAN,, Karel (referee) ; Šťastník, Stanislav (advisor)
The master´s thesis deals with verification of thermal insulating property of thermoreflection foil insulations. The teoretical part of thesis focuses on the energy demand of buildings, the problems of heat transfer material, terms required for study of thermoreflection thermal insulation and experimental methods for determination of thermal insulating properties of insulators. In the next part the chapter is accompanied by an overview of the most common insulation materials which used in construction. The last part of teoretical part is devoted to the description of thermoreflect formation and analysis of the spread of thermal insulating layers of thermoreflection thermal insulation. The first part of thesis is devoted to the use of thermoreflection therm insulation in buildings. The second part of thesis is devoted to the design, assembly and calibration of the measuring device that uses a method of protected warm chamber. It is declared as a binding method of detection of the heat transfer performance of thermoreflection thermal insulation. The developed measuring device allows detection of endpoints in some direction of propagation of heat. Measurment of heat transfer coefficient devoted the third part of practical part. This part contains a description of the samples used for the measurement of the heat transfer coefficient. In the fourth chapter of the practical part are presented the results of the heat transfer coefficient measurments on selected samples of thermoreflection foil insulation. It is shown the characteristic of heat transfer coefficient of individual samples, the dependence of the heat transfer coefficient on the position of the sample in the measuring device and the recommendation of an appropriate use of sample in the works for the climatic conditions of the Czech republic. The work concludes the chapter of comparing and evaluating of all samples with practical recommendations.
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Study utility properties of heat-reflective insulation for the buildings
Rauchfussová, Karolína ; TROJAN,, Karel (referee) ; Šťastník, Stanislav (advisor)
Presented work deals with the study progressive heat-reflecting foil thermal insulating materials and defines their thermal insulation properties. The work describes a transport mechanism of thermal energy in the structure of heat-reflecting materials, their physical properties, especially heat resistance, compared to the conventional thermal insulating materials available on Czech market. The main applications ways and installation methods of these materials (especially in low-energy and passive buildings) are also shown. The practical part is focused on asembling the measuring device HOT BOX in accordance with the valid standards, to determine the heat resistance of heat-reflecting materials. In next step the measurement of reflection of aluminum foils (an integral part of the structural arrangement heat-reflecting foil insulations) was performed.
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The Effect of Sawdust on the Refractoriness of Insulation Chamotte
Smékalová, Veronika ; Kotásek, Martin (referee) ; Sokolář, Radomír (advisor)
Lightweight refractory products have their place between refractory materials. Still the most common way of lightweighting is by using burnable components. This bachelor work includes the theoretical part, which deals with raw materials for lightweight fireclay, manufactory, and also testing lightweight refractory products. The second part of this work deals with foreign research and its results in this area. The practical part examines the influence of the types of sawdust (spruce or beech) on properties of lightweight refractory materials. The work focuses mainly on heat resistance, temperature usability, thermal conductivity, and density. These properties are evaluated with consideration to the ash which is created by burning sawdust.
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Influence of the oxide layer on the cooling of steel surfaces
Resl, Ondřej ; Pohanka, Michal (referee) ; Chabičovský, Martin (advisor)
This thesis deals with the influence of the oxide layer on the spray cooling of steel surfaces. As part of the work steel samples with oxide layer are made and the thickness, porosity and surface roughness of this layer are characterized. The average thermal conductivity of porous oxide layer is determined for different regimes of oxidation. Further, the influence of the oxide layer on the heat transfer coefficient during the spray cooling is experimentally investigated on created samples and the basic numerical simulation of the cooling is done for selected experiment with oxide layer. The thesis also contains theoretical introduction to given issue.
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Systems of energy efficient buildings
Šlampová, Kateřina ; Horák, Petr (referee) ; Počinková, Marcela (advisor)
The topic of this diploma thesis is systems of energy efficient buildings with a focus on the building envelope. The first theoretical part describes the quantities that we consider when designing the building envelope. The second half of the theoretical part is with reference to the experimental part of the thesis focused on a special type of vertical perimeter structure, namely walls with live vegetation installed from the outside of the structure. The second, practical part of this work, deals with the design of heating and hot water supply for a multifunctional building. The design is elaborated in two variants - heating by means of radiators in the first variant and in the second variant by means of floor heating for residential units of the solved building. The third part define an experiment, which had the task of comparing the measured quantities on two types of vertical perimeter structures, namely a structure with growing greenery from the outside and an identical structure only without a layer of greenery. At the same time, the task was to check the possible influence of the applied greenery on heat losses, and thus the design of the heating system.
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Study of energy accumulation during phase change of paraffin wax
Lapčíková, Tereza ; Krouská, Jitka (referee) ; Zmeškal, Oldřich (advisor)
This thesis deals with the study of the process of energy storage during phase transformation, the so-called latent heat for commercial materials of the Rubitherm® RT line (Rubitherm Technologies GmbH) with applications in the construction industry. The thermophysical properties of Rubitherm® RT35HC, RT28HC and RT18HC materials differing in phase transformation temperature were investigated using the transient method. For the Rubitherm® RT35HC material a value of the thermal conductivity coefficient in the solid phase of 0.21 W/m/K and in the liquid phase of 0.23 W/m/K was determined. The specific heat capacity value in the solid phase was determined to be 1980 J/kg/K and in the liquid phase 1995 J/kg/K. For Rubitherm® RT28HC, the value of the thermal conductivity coefficient in the solid phase was determined to be 0,23 W/m/K and the value of the specific heat capacity in the solid phase was determined to be 1997 J/kg/K. For the Rubitherm® RT18HC material, a liquid phase thermal conductivity coefficient of 0,27 W/m/K and a liquid phase specific heat capacity of 2010 J/kg/K were determined. Using differential scanning calorimetry (DSC), the melting temperature of the Rubitherm® RT28HC sample was determined at 27.43 °C and solidification at 23.51 °C, while for the Rubitherm® RT35HC sample melting occurred at 36.51 °C and solidification at 31.86 °C and 32.28 °C. In the experimental part of this work, modifications were made to the measuring apparatus used in such a way that it could be used for the study of materials that change their state of matter during the experiment.
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Study of the behavior of vacuum insulation based on secondary raw materials
Zelenka, Jakub ; Novák, Vítězslav (referee) ; Zach, Jiří (advisor)
The bachelor's thesis deals with an extensive literature research on the topic of vacuum insulation and their use in civil construction and other areas of application. The theoretical part is devoted to the composition of vacuum insulation and materials suitable for the production of their cores. Based on the performed research, the design of possible alternative core insulators based on natural secondary raw materials has been conducted. These can be used in the production of vacuum insulation.
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Study of the behavior of insulating materials in a high humidity environment
Havelka, Jindřich ; Peterková, Jitka (referee) ; Zach, Jiří (advisor)
Extruded polystyrene (XPS) is presented as non-absorbent material and it is applied in building construction with high moisture, such as inverted roof. The reason for that is a very good ratio of thermal and mechanical properties and it is used in moisture-loaded applications due to the closed pore structure and high diffusion resistance factor, which are declared by the manufacturers. Long-term experience and studies show that XPS accumulates moisture during long-term exposure in an environment with high humidity. A long-term water absorption test at full immersion for 84 days has been proposed to better illustrate the trend of increasing water absorption. A total of 6 products from different manufacturers that are recommended for inverted roof application, were tested. All tested XPS products have reached high amount of water absorption. The main goal was to map the real properties of XPS at high humidity loads. It was found that each product showed a different degradation of thermal conductivity at the same volume moisture value. Furthermore, there was found the connection between the surface structure and amount of water absorption. Products with waffle structure had higher humidity than products with a fine structure.
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