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Entwicklung eines wissensbasierten modularen Verfahrens zur Beurteilung der thermischen Verkrümmung von IndustriedampfturbinengehäusenHeße, Christian 18 March 2011 (has links)
Thermische Gehäuseverkrümmungen spielen bei der Dimensionierung von radialen Spielen in Industriedampfturbinen eine große Rolle. Die zuverlässige Vorausberechnung der Gehäuseverkrümmung ist wichtig, um einerseits möglichst kleine Spiele und damit hohe innere Wirkungsgrade erzielen zu können und andererseits Schäden in Folge von Spielüberbrückungen auszuschließen. In der vorliegenden Arbeit wurde die Gehäuseverkrümmung mit analytischen Methoden und mit Hilfe von 3D-FE-Analysen untersucht.
Eine neue semi-analytische Berechnungsmethode auf Basis eines Stufenkörpermodells wurde entwickelt. Damit lassen sich komplexe Geometrien und unterschiedliche thermische Randbedingungen berücksichtigen. Der Einfluss von Rotationsasymmetrien auf die Verkrümmung wurde mit Hilfe einer FE-Parameterstudie untersucht und in Form von Einflussfaktoren in das Modell integriert. Im Vergleich zu vereinfachten FE-Modellen und zu gemessenen Verkrümmungen an realen Turbinengehäusen zeigt das semi-analytische Modell eine gute Übereinstimmung.
Weiterhin wurde das Verkrümmungsverhalten von Industriedampfturbinengehäusen mit Hilfe von 3D-FE-Analysen untersucht. Durch Abgleich von gemessenen und simulierten Temperaturen und Verformungen konnten Erkenntnisse zum Modellaufbau gesammelt werden. Da die thermischen Randbedingungen bei der Simulation von Gehäuseverkrümmungen von größter Bedeutung sind und Defizite beim Wissensstand zum Wärmeübergang erkannt wurden, sind umfangreiche Messungen des Wärmeübergangskoeffizienten durchgeführt worden. Damit wurde ein Beitrag geleistet, FE-Analysen zukünftig auch bei Dimensionierungs- und Auslegungsfragen einsetzen zu können.
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SENSITIVITY STUDIES ON THE THERMAL MODEL OF A SOLAR STEAM TURBINECALIANNO, LUCA January 2016 (has links)
Förr i tiden, ångturbiner har främst använts för baskraft operation. Numera med den ökade utvecklingen av varierande förnyelsbara är samma ångturbiner motstå högre cykliska operativa system med mer frekvent uppstarter och snabbt föränderliga laster. Som sådan, förbättra den operativa flexibiliteten hos installerade och framtida utformad ångturbiner är en viktig aspekt för att övervägas av utrustning. Ångturbin uppstart är en intressant fas eftersom anses vara den mest intrikata av transienter. Under denna fas kan maskinen potentiellt utsättas för omåttlig termiska spänningar och axiella gnugga på grund av differentiell termisk expansion. Dessa två termiska fenomen antingen konsumera komponent livstid eller kan leda till maskinhaveri om inte kontrolleras noggrant. Som sådan, det finns en balans som skall beaktas mellan ökande turbin uppstart hastighet samtidigt som säker drift och livslängd bevarande av dessa maskiner. För att förbättra den transienta operationer av ångturbiner, blir det viktigt att undersöka deras termiska beteende under uppstarter. För att göra detta, är det viktigt att ha verktyg som kan förutäga den termiska responsen hos maskinen. I denna avhandling fungerar effekterna av olika aspekter och randvillkor om resultaten av ST3M, en KTH internt verktyg, undersöktes med syfte att förstå hur stor blev deras inverkan på sättet att fånga den termiska beteendet hos turbinen i termer av metalltemperatur och differentiell expansion. En industriell högtrycksturbinen validerades mot uppmätta data och genomförs på en känslighetsanalys; denna analys visade att den geometriska approximation införa fel i resultaten, att användningen av empiriska Nusselt korrelationer ge liknande resultat som den validerade modellen och att håligheten antaganden har en stor inverkan på utvecklingen av expansionsskillnaden. Slutligen har en strategi för att validera någon annan liknande turbin till en av studien fallet föreslås för att ge en vägledning för framtida arbeten i hur att validera en modell och vilka är de mest inflytelserika parametrar att ta hand om. / In the past, steam turbines were mostly used for base load operation. Nowadays, with the increased development of variable renewable technologies, these same steam turbines are withstanding higher cyclic operational regimes with more frequent start-ups and fast changing loads. As such, improving the operational flexibility of installed and future designed steam turbines is a key aspect to be considered by equipment manufacturers. Steam turbine start-up is a phase of particular interest since is considered to be the most intricate of transient operations. During this phase, the machine can potentially be subjected to excessive thermal stresses and axial rubbing due to differential thermal expansion. These two thermal phenomena either consume component lifetime or can lead to machine failure if not carefully controlled. As such, there is a balance to be considered between increasing turbine start-up speed while ensuring the safe operation and life preservation of these machines. In order to improve the transient operation of steam turbines, it becomes important to examine their thermal behavior during start-up operation. To do that, it is important to have tools able to predict the thermal response of the machine. In this thesis work the impact of different aspects and boundary conditions on the results of ST3M, a KTH in-house tool, were investigated with the aim of understanding how large was their impact on the way to capture the thermal behavior of the turbine in terms of metal temperature and differential expansion. A small industrial high pressure turbine was validated against measured data and implemented on a sensitivity study; this analysis showed that the geometrical approximation introduce errors in the results, that the use of empirical Nusselt correlations give similar results to the validated model and that the cavity assumptions have a large impact on the trend of the differential expansion. Lastly, a strategy to validate any other similar turbine to the one of the study case was proposed in order to give a guide to future works in how to validate a model and what are the most influent parameters to take care of.
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Comparative analysis of development potential for biomass- vs coal-fired powerplants in Henan province,ChinaWang, Dongcan January 2017 (has links)
Coal-fired power plants’ typically large capacity and relatively low electricity generation costs in the Chinese power market can be compared with their typically low specific thermal efficiency and older age on average. At the same time, the environment pollution caused by local coal-fired power plants has started to receive due attention. Sustainable renewable energy sources and the application of effective conversion technologies for those has become a top priority of China's current energy strategy. Biomass in general and anaerobic biogas in particular can be regarded as clean, locally available renewable energy resources. Replacing coal with biomass-derived energy is especially relevant for certain locations in China. For the case of Henan province, work has already been undertaken by the local authorities for the proper estimation of the biomass potential and the selection of most applicable energy conversion technologies with the lowest environmental footprint to replace aging coal-fired plants with various biomass-based power generation facilities. / Kolkraftverkens typiska stora kapacitet och relativt låga elproduktionskostnader på den kinesiska elmarknaden kan jämföras med deras typiskt låga specifika verkningsgrader och äldre ålder i genomsnitt. Samtidigt har miljöföroreningarna som orsakas av lokala kolkraftverk börjat uppmärksammas på riktigt i Kina. Hållbara förnybara energikällor och tillämpningen av effektiv konverteringsteknik för dessa har blivit en topprioritet för Kinas nuvarande energistrategi. Biomassa i allmänhet och anaerobisk biogas (rötgas) i synnerhet kan betraktas som rena och lokalt tillgängliga förnybara energiresurser. Byte av kol mot biobränslen blir särskilt relevant för vissa platser i Kina. När det gäller Henanprovinsen har en del arbete redan gjorts av de lokala myndigheterna för en korrekt uppskattning av biomasspotentialen och en analys av de mest tillämpliga teknologier för omvandling av bioenergi med lägsta miljöpåverkan som ersätter åldrande koleldade anläggningar med olika biobränslen.
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Parní turbína v paroplynovém cyklu / Steam Turbine in the Combi CycleFiloušová, Natálie January 2017 (has links)
Diploma thesis named Steam turbine in the combi cycle deals with design of low pressure part of three-body turbine and it’s lateral outlet throat to the air condenser. Before the design itself, the thermal schema of entire turbine is calculated. Than follows the detail draft, the strength calculations are included as well. Turbine has any technological consumption of steam or any regenerativ consumption. Turbine will be suplly to Panama. The thesis includes following drawings: cut of flowing part, design of outlet throat and fixing of inner body in outer body of low pressure part. The diploma thesis is created for Doosan Škoda Power company.
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Kondenzační parní turbína / Condensing steam turbineTrávníček, Zdeněk January 2017 (has links)
The aim of the master’s thesis is to design a condensing steam turbine based on given inputs. Firstly, a design and computation of heat balance is made, followed by thermodynamic calculation of steam turbine channel and a design of compensatory piston of axial forces. Last part of the thesis consists of a review of a change of cooling water temperature in condensator on last turbine stages. The structural drawing of longitudinal section of turbine is included as well.
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Parní turbína pro biomasovou elektrárnu / Steam Turbine for Biomass Power PlantIngr, Adam January 2019 (has links)
This master‘s thesis deals with thermodynamic calculation of condensing steam turbine with controlled extraction point for heat exchanger, into biomass power plant block. Rated output of steam turbine is 6.5 MW and rated output of heat exchanger is 4.5 MW. At the beginning of the thesis is explained the heat scheme and the effect of heat regeneration on the design of turbine. Attention was also paid to the heat equation of individual thermal diagram devices and the calculation of the steam mass flow rate. The next part is focused on thermodynamic calculation of the turbine, followed by mechanical stress calculations. The calculation is divided into preliminary design and detailed calculation. At the end, the performance analysis of the designed turbine is made.
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Parní turbína - tvorba a odvod kondenzátu / Steam turbine - condensation formation and dischargeZouhar, Adam January 2019 (has links)
Master thesis is dealing with the issue of condensate creation and removal from the Nesher Ramle steam turbine during start-up and steady state. At the beginning a preliminary calculation of heat balance and the turbine itself is done. It is followed by description and design of drainage system supplemented by calculation of the steam flow through the orifices. Steam flow calculation was done via S. D. Morris, Pavelek with Kalčík and Ambrož, all three methods were compared. The main goal is the theoretical calculation of the amount of condensate created during start-up which is influenced by its initial state from which it is started. Three default states are considered, cold, warm and hot. In the last chapter the comparison of theoretical calculation with the measured data on real turbine is done and it is supported by the evaluation of the data from the measurement of the steam turbine at steady state on maximum power and half power. From the steady state analysis, percentage of water flow to expander from the total amount of condensate formed in the turbine were obtained.
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Topné výměníky, vliv zapojení na účinnost cyklu / Heat exchangers, influence of cycle efficiencyKhůlová, Jitka January 2019 (has links)
The master's thesis deals with district heat exchangers in a thermal steam cycle of combined heat and power plants and with types of condensate cascades in the multilevel heating systems. Calculation of the thermal efficiency of electricity generation is provided for the investigated thermal cycle, which was modified for three different types of cascades. Besides that, a comparison of useful electric power and electricity generation through one year period of working is made. A significant part of the work is devoted to the design of district heat exchangers, including the calculation of thermal power and heat transfer area. Main dimensions are proposed for each exchanger together with a basic drawing.
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Návrh paroplynového cyklu pro teplárenský provoz / Design of a combi cycle for heating plantRovný, Jan January 2020 (has links)
Nowadays, European power production has to meet requirements than ever before. Environmentally oriented efforts end of coal mining and burning of coal, on which economies of a great number of countries depend. The main objective of these efforts is primarily the production of green energy from renewable energy sources and reduction of dependence on fossil fuels. However, the disadvantage of renewable sources (photovoltaics, wind farms) is their dependence on the weather conditions. As a result, there might be delays in supply of electricity, which must be compensated. One of the solutions is the launch of a combi cycle plant, which has the possibility of almost prompt start-up and electricity production. The combustion of gas and liquid fuels also ensures almost emission-free operation. In addition, thanks to the use of waste heat energy from the gas turbine, it is possible to operate the combi cycle unit with the character of a power plant and as a heating plant. The aim of this thesis is to search for combi cycles and balance calculation of the combi cycle heating plant under given conditions. In the last point, the approximate dimensions of the calculated heating plant are given.
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Paroplynová turbína pro akumulaci energie / Steam-gas turbine for energy storageStaněk, Štěpán January 2020 (has links)
Master thesis discusses the growing need of electric energy storage and its effectivity and capacity. It describes an overview of possible technologies with their advantages and disadvantages. Greater attention is paid to the storage of energy in gas, so-called Power to Gas, which combines the electrolytic production of hydrogen from water and the Sabatier reaction to produce synthetic methane. This technology is introduced in the so-called SIT Brno cycle of Siemens Industrial Turbomachinery company. The main part of the thesis is focused on the description of this cycle and on the calculation of the steam-gas turbine (high-pressure and low pressure module). This thesis describes the methodology of turbine calculation and the composition of the steam gas mixture after combustion of methane. The carbon dioxide formed by combustion in the steam-gas mixture generator was replaced by steam. Part of the diploma thesis are drawings of cross-section of individual turbine modules.
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