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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.
111

Návrh parního plynového kotle / Gas steam boiler design

Vacek, Jiří January 2021 (has links)
The aim of this thesis is a draft of a gas steam boiler with steam output of 200 t/h. The first part of the paper provides stoichiometric calculations, then there are calculations of the dew point, boiler efficiency and the amount of gas. After that, calculations and a draft of the combustion chamber are carried out and then heat balances are drafted. In the following text, geometric properties of individual heat exchanging surfaces are drafted. At the end, there are control calculations. This thesis contains a blueprint of the gas steam boiler.
112

CFD analýza tepelného zatížení trubkovnice / CFD analysis of thermal stress of a tubesheet

Vince, Tomáš January 2021 (has links)
This diploma thesis focuses on the phenomena of multiphase flow in a steam generator as a one of probable causes of tubes and tubesheet weld cracking. In the first part of the work, a research was carried out focusing on the boiling and the phenomenon of two-phase flow in technical applications, its characteristics and properties. The thesis continuous with an overview of available numerical multiphase models in the ANSYS Fluent 2021 R1 and a research of previously published works focused on two-phase flow with the presence of boiling. The research is followed by a description of the particular boiler, which is part of the nitric acid production plant in the chemical company DUSLO, a.s., its operating conditions and a more detailed description of the issue that is being addressed in this thesis. The second part of the work continuous with a description of the computational model, including a description of the geometry of the model and used simplifications, the computational mesh and the description of boundary conditions. Important part is the description of calculation setting of steady-state and transient CFD simulations in ANSYS Fluent. Finally, the results of the two-phase flow calculation are presented and then discussed in the conclusions.
113

Návrh autonomního topného zdroje / Project of Autonomous Heating Source

Pejcl, Jiří January 2014 (has links)
The diploma thesis deals with design of a suitable heat source for heating and hot water. There are dealt with operational costs of different types of heat sources, which are compared with one another. The next part is the implementation of specific proposal of the heat source - heat pump ground/water with deep wells and measuring system. The last part describes measuring several operating modes of the heat pump.
114

Kotel na spalování výpalků lihovarů / Steam boiler for fytomass

Baláš, Jiří January 2008 (has links)
The purpose of this Diploma Thesis was the construction design of the steam boiler for fytomass. For the specified parameters of biomass have been gradually implemented stoichiometric calculations of which are further based calculation of enthalpies of combustion gas. In the next part have been dealt with heat balance of the boiler, the efficiency of the boiler, recirculation of exhaust gases and the temperature of the combustion gases in outlet from fire. Thereinafter, the proposal of particular heat surfaces of steam boiler was solved, so that the resulting number and size correspond to the desired parameters. The parameters are temperature, pressure and the amount of steam.
115

Kotle na spalování biomasy / Steam boiler for biomass

Knichal, Jaroslav January 2008 (has links)
At present, people already fully aware of how expensive it is energy dependence on fossil fuels. Trying to reduce this dependence goes hand in hand with environmental limits, which restrict the production of dangerous compounds. Biomass is a fuel that does not create large amounts of sulfur and carbon dioxide generated during combustion is in a closed cycle. Different types of biomass have different calorific value, and therefore different demands on the quantity needed to produce MWh. It is therefore necessary to choose the fuel with regard to the availability of in the site.
116

Odsíření spalin fluidního kotle. / Desulphurisation of flue gas fuidized bed boiler.

Miklík, Tomáš January 2009 (has links)
The aim of this thesis is to design a desulphurization device for the fluid boiler. In the fluid boiler, fuel with extremely high sulphur content is burnt and the combustion products are not desulphurized to the required level, therefore it is necessary to build a desulphurization device. The thesis consists of two parts – theoretical and practical. In the theoretical part I stated the emission limits of sulphur dioxide, elaborated possible desulphurization methods and described the sorbets suitable for desulphurization. In the practical part I chose a dry desulphurization method with fluid reactor, to which a dry sorbent on the basis of lime hydrate is dosed. For the required parameters, I designed the whole desulphurization equipment including cloth filters, all necessary silos and major components. It is a design proposal with a layout and a spatial model.
117

Roštový kotel na spalování peletek / Steam boiler with wood pelets firing.

Zekič, Daniel January 2010 (has links)
The aim of this diploma thesis is the construction design of the steam boiler burning pellets. Set parameters: 450°C; 5,2 MPa; 30t/h. Decision procedure: stoichiometric calculation, energy balance, calculation of combustion chamber and heat delivery surface.
118

Bilanční model jednotky pro energetické využití biomasy / Heat and mass balance model of unit for biomass combustion

Tomšů, Ondřej January 2010 (has links)
This work deals with the creation of a mathematical model for calculating mass and energy balances of the energy units for utilizing the biomass combustion by computational software W2E and it is engaged in necking the validity of the balance model for the real technology unit for combustion different types of biomass. There are presented basic informations of balances and described the procedure how to solve balance calculations of energy units. Introductory part deals with biomass as a renewable energy source, which has a large potential in energy system. There are presented all its important parameters, its types, methods of treatment and utilization power production. Next chapters focus on biomass combustion devices, theirs classification and theirs technological principles. For the specific type of biomass boiler (of capacity 1 MW with movable, inclined grid) - here was created balance model. The choice of this equipment is preferred primarily by the fact that the middle capacity power boilers can be considered as the most suitable heat sources in terms of efficient combustion of biomass. Another motivation is a key objective of this work, which is creation of balance model of the unit which energy utilizes of biomass, which belong into this category of heat sources and is available for real measurements. There are presented the available computing systems for balance modeling with the preference of the analysis program W2E and MS Excel. They are verified as the best instruments for creation balance model at the practical chapter of this work. The main output of presented thesis is thus balance model developed in W2E program which has been compared and modified to the real characteristics of biomass boiler. For this purpose were used the archived data from previous measurements and new actual measurements, which focused on the acquisition of the missing operational data and verifying the reasons of variance of the model and real status. In the conclusion, there are evaluated the basic operating parameters of the technology in various operating states by W2E analysis model.
119

Parní kotel na spalování lihovarských výpalků 50t/h. / Steam boiler burning fytomass waste

Plot, Rostislav January 2010 (has links)
This thesis deals with the calculation of the boiler on stillage. Nowadays, when there's fossil fuels are just biomass seems adequate compensation. The great advantage of biomass boilers is a small amount of emissions, especially the greenhouse gas CO2. Of a given fuel composition is made thermal calculation and dimensioning of heat transfer surfaces of steam boilers. The resulting calculation must follow the parameters of steam at the outlet from the boiler.
120

Vysoce efektivní kondenzační kotel na zemní plyn / Heigh effective condensation boiler feeded by natural gas

Renfus, Jaromír January 2010 (has links)
The dissertation is concerned with a problem of condensing boilers. The attention will apply to the condensing boiler which is filled in an absortion springle for a better an-nealing of exhaust gas. On this account the dissertation is possible to divide by some parts. There is a generally resolution of a condensing boiler´s principle and an effective annealing of exhaust gas for low temperatures in the first part. A description of an ab-sorption circulation follows in the second part. A practical part solves a suggestion of the condensing boiler with an absorption afterheat removal springle, an assesment of working parameters and a calculation of heat transfer surfaces. A technoeconomic ana-lysis of a proposed arrangement is made in the final part.

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