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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Termodynamické tepelné čerpadlo / Thermodynamic heat pump

Kadlec, Stanislav January 2017 (has links)
The aim of the Diploma Thesis is to discuss the design and construction solution for circulation of the thermodynamic heat pump especially used in the heating industry with stoichiometric combustion of chosen natural gas. The basic components of the proposed heat pump are turbine, compressor and gearbox. To solve the presented aims, the thermodynamic calculation of the individual components, the determination of the efficiency of the whole equipment and the analysis of the physical properties of the natural gas with regard to the specified input and output parameters were considered. In addition, an analysis of the individual components design of the proposed equipment was carried out, on the basis the technically most acceptable variant was chosen and the equipment construction was carried out incl. connecting elements. Drawing documentation is part of the attachments. On the basis of the analysis, it can be stated that the proposed plant leads to energy savings, is ecologically sufficient and has been shown to have approximately twice the amount of heat dissipated than without its use.
82

Výzkum deformačních mechanismů pokročilých lehkých slitin / Investigation of deformation mechanisms of advanced light-weight alloys

Németh, Gergely January 2016 (has links)
The objective of this thesis is to investigate the mechanical and damping properties in AZ91 alloys with different boron concentrations and in two experimental alloys based on commercial pure magnesium. Further aim is to identify the influence of heat treatment of alloys AZ91+B on the properties mentioned above. Micro-structural observations were achieved by optical and scanning electron microscope. Mechanical tests were performed in a wide range of temperatures from 23řC to 300řC and, simultaneously, the acoustic emission was recorded at room temperature. The temperature spectrum of internal friction was determined in the temperature range from 23řC to 400řC. Moreover, the amplitude dependence of damping properties of materials were studied. Phenomena leading to dissipation of mechanical energy in the temperature spectrum were determined by micro-structural observation.
83

Analýza korozní odolnosti strojního zařízení v čistírnách odpadních vod

Dobrocká, Iva January 2019 (has links)
The thesis deals with the analysis of corrosion resistance of machinery used in wastewater treatment plants. The theoretical part of the thesis deals with the composition of waste water in terms of corrosion aggressiveness and describes the corrosive en-vironment in the WWTP. Furthermore, the types of corrosion are characterized and the exposed machinery of the WWTP with the highest level of corrosion is determined. The experimental part of the work is devoted to the analysis of corrosion resistance of corrosion-resistant austenitic steels and structural non-alloyed steels with duplex zinc coating and acrylate paint. Furthermore, structural low-alloyed steels with chemical-heat treatment by nitriding and ferritic nitrocarburizing in gas and structural non-alloyed steel with duplex system of phosphate + epoxy coating and zinc + epoxy coating are analysed as a possible replacement for stainless steels. The steels with duplex system of zinc + acrylate coating used in practice show little corrosion resistance (the first signs of corrosion after 12 h and 24 h). some chemical-heat treated steels and steel with duplex sys-tem of zinc + epoxy coating achieved the same corrosion resistance as stainless steels (264 h test time) and can be used in technical practice.
84

Návrh energeticky úsporné dřevostavby

Limberg, Tomáš January 2019 (has links)
Master thesis is focusing on desiging of low energy wooden building with hers architectonic and disposition problems. Projecting also inculde every mechanical drawings, which is needed for building permision and technical documents as well.. Projecting also included thermal and technical solution for building envelop. Master diploma thesis got static solution for selected elemnts needed for wooden construction.
85

Vliv teploty na pevnost lepeného spoje nábytkových hran z exotického dřeva

Maršálek, Hynek January 2017 (has links)
This dissertation thesis deals with the influence of temperature on the strength of the bond on furniture parts edges from exotic wood and particleboards furniture parts for the side panels. This theme covers the furniture that is during storage and transport exposed to high temperatures. It significantly affects the strength of glued joints with hot melt adhesives. This makes it necessary to pay attention when selecting the adhesive. It must withstand not only high but also low temperatures that occur during transport furniture. The practical part is focused on the problems of thermally stressed connections between the chipboard and furniture edge from exotic wood. Samples were edged by melt adhesive based on EVA copolymers, and polyurethane-based adhesive. Test samples were subjected to cyclic thermal loading that simulated conditions of the internal environment of the transport unit. Testing was used examinations peel and oblique pressure skid. The output data from these tests were evaluated between themselves and compared with edge finished by ABS edge. As a supplementary method was also used bending test, that examined the size of the internal stress in the veneer edge
86

Environmentální řešení objektu penzionu ve Velké Bíteši / Environmental solutions of building guesthouse in Velká Bíteš

Bachmayer, Milan January 2022 (has links)
The main aim of the Master project is a design of the guesthouse with wellness, which has nearly zero-energy consumption and is located in Velká Bíteš. For design is used ARCHICAD, for numeric is used DEKSOFT. This Master project consists of three parts. The first part focuses on the design of the guesthouse, the second part concentrates on a technical design and the third part focuses on the draft of different energy sources, its comparison and evaluation. Guesthouse is a three-story building with walkable flat roof. Wellness, cold rooms and massages are located in the basement. Other places of floor consist of sanitary facilities, technical rooms and common rooms. There are also guest rooms on the other floors and a conference hall on the third room. This final draft has much more positive outcomes than other alternatives; with respect to primary energy and impact on the environment. However, the final draft has higher purchase costs and its financial and operational economy is extremely dependent on the prices of electric power.
87

Identifikace tepelné vodivosti a tepelné kapacity stavebních látek metodou „Hot Wire Method“ / Identification of Thermal Conductivity and Thermal Capacity of Building Materials by the "Hot Wire Method"

Průša, David January 2019 (has links)
This aim of task deals with study of heat dissipation mechanisms and the description of physical phenomena, which is accompanied by non-stationary measurement of thermal characteristics by the method "hot-wire method". In particular, we observe the coefficient of thermal conductivity and its dependence on various variables such as the temperature of the measured sample, its moisture state, the volume of the sample and its porosity. The above mentioned findings are used for the invention of the measuring device of a nonstationary gauge, which is based on regular heating and is dedicated to measuring the thermal conductivity coefficient and the heat capacity by the "hot-wire method" method. In the last part of the thesis is verified functionality of the proposed measuring device, the suitability of the created algorithm for the processing of the measured data and the evaluation of the results was verified. The reproducibility of the measurements was verified and the measured results were compared with the measurement methods, which are commonly used. the influence of humidity on the coefficient of thermal conductivity.
88

Tepelné čerpadlo vzduch - voda / Air source heat pump

Krejsa, Petr January 2017 (has links)
The master's thesis deals with the description of heat pump technology (HP) and its use for apartment buildings. The theoretical part contains an introduction, performance of heat pump technology, in particular a compressor heat pump (CHP). In this section is also mentioned about heat pumps for an apartment buildings. Main focus of this thesis is a design of a compact air-water heat pump for the company AISECO spol. s.r.o. This section is focused a design of an individual components of cooling circulation together with proposal of the circulation and principle of operation.
89

Energetický posudek a PENB při výměně zdroje tepla v rodinném domě / Energy Assessment and PENB when Replacing Heat Source in a Family House

Minář, David January 2018 (has links)
The diploma thesis deals with energy assessment and proof of energy performance of the building when replacing the heat source in a family house. The theoretical part deals with thermography and thermocamera in energy practice. The experimental part of the thesis was focused on the thermographic survey of the object and the evaluation of the outputs. The computational part focuses on the energy analysis of the assessed energy economy.
90

Návrh zařízení pro úpravu mikroklimatu v rekonstruovaném rodinném domě / Design of an HVAC system in a retrofitted family house

Vacenovský, Jan January 2018 (has links)
This work is devoted to the design of a microclimate facility in a family house. The first part contains analysis of thermal losses before and after using thermal insulation. Based on this analysis, a heating system is proposed, including the necessary technical calculations for the operation of the system. As a heat source, a condensing boiler is selected. At the next point, the thesis focuses on the calculation of the heat gains in selected rooms in order to design a cooling device. A multisplit system is selected for cooling the rooms. In the next part the thesis deals with the design of forced ventilation of selected rooms. The ventilation system provides the necessary air exchange and covers heat losses through ventilation. At the end of the thesis is outlined the concept of regulation of individual systems and also the requirements for individual professions are described.

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