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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

Climate Neutral Roadmap in Fossil Free Competitiveness for Paroc, Sweden : what Paroc can do to meet up with the roadmap from Fossil Free Sweden / Klimatneutral Färdplan i Fossilfri Konkurrenskraft för Paroc, Sverige : vad Paroc kan göra för att möta upp färdplanen från Fossilfritt Sverige

Mörk, Felix January 2021 (has links)
Today’s society is standing in front of a revolution where fossil energy should be replaced with renewable energy. Governmental agencies and policy makers have formed goals and regulations to become greener, and the organisation Fossil Free Sweden has published roadmaps for fossil free competitiveness. Therefore, this report has connected Paroc’s operations with a roadmap for fossil free competitiveness to form a strategic environmental plan. Early, it was recognized that the field was big and a limitation to CO2-emissions during production were established. The facts were gathered mostly throughout literature studies, scientific publications/articles, and personal communication with personnel at Paroc/Owens Corning. The results gave a description over fossil free competitiveness for the construction sector, previous, and current sustainability efforts at Paroc. After that, the report lifted suggestions of modifications to the mainstream process. Focus laid on the reduction of coke, propane, and dolomite. Later, the report discussed a possible strategy to become fossil free by 2045. It found out that there are many approaches to become climate neutral. Moreover, a need for practical testing of the solutions in the mainstream processes, and that emissions can be calculated in an absolute of relative way.
82

DEVELOPMENT OF A UNIQUE EXPERIMENTAL FACILITY TO CHARACTERIZE THE FATIGUE AND EROSION BEHAVIOR OF CERAMIC MATRIX COMPOSITES UNDER TURBINE ENGINE CONDITIONS

Panakarajupally, Ragavendra Prasad January 2020 (has links)
No description available.
83

Feedback Control for Maximizing Combustion Efficiency of a Combustion Burner System

Horning, Marcus 10 June 2016 (has links)
No description available.
84

Further development of Sand Bed Burner / Vidareutveckling av Sandbäddsbrännare

Jansson, Adam January 2014 (has links)
To determine whether a weapon system meets the requirements set for insensitivity, the system is getting exposed for special tests. One of these tests shows how the system reacts when it ends up in a fire. This test is called the "Fast Cook-Off (FCO) Test", called FCO-test, and performed with a Sand Bed Burner (SBB). According to primary testing provision, the fuel for this test is used of jet fuel such as Jet A-1. A project at Bofors Test Center (BTC) is in progress to use an alternative fuel of Liquefied Petroleum Gas (LPG). This fuel is very advantageous compared to jet fuel in terms of environmental impact, work environment and testing costs. The aim of this thesis is to improve the existing test equipment considering fire over the entire surface and solve the problems with dropped gas flow and freezing of gas bottles. SBB works in the sense that the new petrol LPG streams into the SBB and expands in the free space below the sand bed before the gas will diffuse through the bed of sand and the fire engulfs the object. LPG is a condensable gas that requires oxygen. LPG exceed from liquid to gas phase and needs a large lateral surface to take up more energy which results in better evaporationto the phase transfer. Reaction products from complete combustion of LPG are only water vapor and carbon dioxide, the same as in your exhaled air. To solve these problems it was needed to change P11 composite bottles to P45 steel bottles to get a longer evaporation and larger lateral surface. Four flow inlets instead were used of one into SBB for a better stream in the free space under the sand bed. Propane regulators used to get a lower and more constant flow to avoid freezing. Compressed airconnected tothe SBB to geta mix between oxygen and LPG. The result shows in higherheat radiation efficiency even though the flow was settled down to 1/3 with the new propane regulators. In test 2 the value was 37 kW/m2 and in test 7 it was around 57 kW/m2. Because of a smaller flow and bigger steel bottles the freezing disappeared. Smaller grain of sand together with four inlets and compressed air gave a more complete combustion.
85

An?lise do desempenho de um queimador infravermelho funcionando com g?s liquefeito de petr?leo e glicerina

Dantas, Marcello Ara?jo 31 May 2010 (has links)
Made available in DSpace on 2014-12-17T14:08:39Z (GMT). No. of bitstreams: 1 MarcelloAD_DISSERT.pdf: 3032114 bytes, checksum: 1b49aa6af338e06fe387bb398cc85b4b (MD5) Previous issue date: 2010-05-31 / The use of infrared burners in industrial applications has many advantages in terms of technical-operational, for example, uniformity in the heat supply in the form of radiation and convection, with greater control of emissions due to the passage of exhaust gases through a macro-porous ceramic bed. This paper presents an infrared burner commercial, which was adapted an experimental ejector, capable of promoting a mixture of liquefied petroleum gas (LPG) and glycerin. By varying the percentage of dual-fuel, it was evaluated the performance of the infrared burner by performing an energy balance and atmospheric emissions. It was introduced a temperature controller with thermocouple modulating two-stage (low heat / high heat), using solenoid valves for each fuel. The infrared burner has been tested and tests by varying the amount of glycerin inserted by a gravity feed system. The method of thermodynamic analysis to estimate the load was used an aluminum plate located at the exit of combustion gases and the distribution of temperatures measured by a data acquisition system which recorded real-time measurements of the thermocouples attached. The burner had a stable combustion at levels of 15, 20 and 25% of adding glycerin in mass ratio of LPG gas, increasing the supply of heat to the plate. According to data obtained showed that there was an improvement in the efficiency of the 1st Law of infrared burner with increasing addition of glycerin. The emission levels of greenhouse gases produced by combustion (CO, NOx, SO2 and HC) met the environmental limits set by resolution No. 382/2006 of CONAMA / A utiliza??o de queimadores infravermelhos em aplica??es industriais apresenta muitas vantagens do ponto de vista t?cnico-operacional, como por exemplo, homogeneidade no fornecimento de calor, na forma de radia??o e convec??o, apresentando um maior controle das emiss?es devido ? passagem dos gases de exaust?o atrav?s de um leito cer?mico macroporoso. O presente trabalho apresenta um queimador infravermelho comercial, no qual foi adaptado um ejetor experimental, capaz de promover uma mistura de g?s liquefeito de petr?leo (GLP) e glicerina. Atrav?s da varia??o de percentuais de combust?vel dual, foi avaliado o desempenho do queimador infravermelho mediante a realiza??o de um balan?o de energia e das emiss?es atmosf?ricas. Foi introduzido um controlador de temperatura com termopar modulando dois est?gios (fogo baixo/alto), utilizando v?lvulas solen?ides para cada combust?vel. O queimador infravermelho foi submetido a testes e ensaios variando-se a quantidade de glicerina inserida por um sistema de alimenta??o por gravidade. Como m?todo de an?lise termodin?mica para estimativa de carga foi utilizada uma placa de alum?nio localizada na sa?da dos gases de combust?o, sendo a distribui??o de temperaturas medida por um sistema de aquisi??o de dados que registrou em tempo real as medidas dos termopares afixados. O queimador apresentou uma combust?o est?vel para os n?veis de 15, 20 e 25 % de adi??o de glicerina em raz?o m?ssica de GLP, aumentando o fornecimento de calor para a placa. Pelos dados obtidos, observou-se que houve uma melhora na efici?ncia de 1? Lei do queimador infravermelho quando ocorre o aumento de adi??o da glicerina na mistura. Os n?veis de emiss?es de gases poluentes produzidos pela combust?o (CO, NOx, SO2 e HC) atenderam aos limites estabelecidos pela resolu??o ambiental n? 382/ 2006 do CONAMA.
86

Návrh a realizace stavebnice pro výuku a vývoj aplikací s jednočipovými mikropočítači rodiny Atmel AVR / Design and implementation of modules for teaching and developing applications with microcontroller Atmel AVR

LANGMAJER, Miroslav January 2012 (has links)
This thesis is based on the design and production of teaching kits with expansion modules which are based on the Atmel AVR microcontroller. Kit consists of a plate containing processes and basic power modules directly on the board and expansion modules "SIMAČ". "SIMAČ" modules are virtual elements that simulate the real elements and they are commonly used in industrial automation. Because of their cost they are integrated in extension kit as programmable modules. It also contains basic theoretical information about working with ATMEL AVR microcontrollers. Expansion modules with module development board and disc which will be loaded all the schemes, programs and technical documentation for individual districts will be attached to the thesis.
87

DEVELOPMENT OF A SWIRL-STABILIZED PLASMA-ASSISTED BURNER WITH A RING-PIN ELECTRODE CONFIGURATION

Nadia M. Numa (5930774) 15 May 2019 (has links)
<p>A small plasma generation system was first developed using a ring-pin electrode configuration with the goal of producing a plasma disk at the burner outlet. Two distinct plasma regimes were identified: diffused and filamentary. Diffuse discharges were generated at low frequencies while filamentary discharges were generated at moderate to high frequencies. The induced flow fields generated by both diffuse and filamentary plasma discharges were investigated using high-speed schlieren visualization and particle image velocimetry. The rise in gas temperature was measured using optical emission spectroscopy. Lastly, the electrical properties for both types of plasma discharges was measured. The measurements provided a set of pulse parameters for the investigation of the plasma-flame interaction on the atmospheric pressure burner. </p> An atmospheric pressure plasma-assisted burner with a ring-pin electrode geometry was designed and fabricated to investigate the effect of nanosecond repetitively pulsed discharges on methane-air flames. The burner can produce both Bunsen-type and swirl-stabilized flames (helical vane swirlers, swirl number of 0.62) with a modular design to allow for a removable block swirler component. Flame chemiluminescence and direct imaging of flame structure and dynamics was done to understand the burner’s operating limits. The burner can operate 6 – 13 kW flames, with flames stabilizing at approximately 2 inches above the burner exit. The effect of air flow rate on plasma formation was investigated and it was found that the high velocity of the incoming gas changes the plasma regime and electrical properties. Finally, the plasma discharge was applied on lifted, swirled flames and used for plasma-assisted ignition. For lifted swirled flames, we found that a minimum of 100 pulses is required to generate a filamentary discharge in the air stream. Higher number of pulses at high frequencies appeared to extinguish the primary flame. A minimum of 6000 was used for ignition. The plasma-assisted burner will allow for future studies to investigate the plasma flame coupling for various conditions using a wide variety of diagnostics. <br>
88

Návrh spalovací komory 30 kW pro plynná paliva / Design of combustion chamber 30 kW for gaseous fuels

Rychter, Aleš January 2014 (has links)
Master thesis deals with design of combusting chamber for gaseous fuels with predicted thermal output less than 30 kilowatts. Designed equipment will be used as a generator of flue gases with required parameters further used for experimental catalytic unit. Due to the need of draft creation inside the combustion chamber and exhaust pipe is master thesis also deals with design of ejector nozzle, which will be used for this purpose. Opening chapters of this work, considering a theoretical part, are focused on basic classification of combustion chambers and industrial burners. Next and main chapter is dedicated to main goal of this work, which is combustion chamber design, containing necessary calculations divided into balance calculation and construction design. Final chapters deals with above mentioned calculation of ejector nozzle ensuring sufficient draft and also sufficient cooling of flue gases incoming from catalytic unit.
89

Metody pro určování charakteristických parametrů procesů spalování na bázi experimentů a modelování / Methods for Determination of Characteristic Parameters of Combustion Processes on the Basis of Experiments and Modeling

Bělohradský, Petr January 2010 (has links)
The present thesis is concerned with methods for determination and modeling of characteristic parameters of combustion of gaseous fuels. The focus is stressed on formation of nitrogen oxides and heat transfer from hot flue gases into combustion chamber’s walls. Experimental work, which is focused on testing of two burners with suppressed formation of nitrogen oxides, is an important part of the thesis. Its aim is to obtain data that is necessary for further processing and modeling. The work presents two methods that may be used in modeling of characteristic combustion parameters, namely the method based on statistical processing of data and the method based on computational fluid dynamics. The approaches are applied to two devices (burner with two-staged fuel supply, burner with two-staged air supply) with the objective to analyze their parameters. First approach covers detailed planning of burner test prior to its own carrying out (definition of the goal of experiment, choice of input factors and response, experimental plan) and subsequent statistical processing of experimental data. On the contrary, CFD approach offers simulations as an alternative option to traditional experimental methods. The simulation of combustion includes building of computational grid, setup of boundary conditions, turbulence model, heat transfer model and chemical kinetics. Results of simulations are compared with experimental measured data.
90

Усовершенствованная камерная печь с автоматизированным импульсным нагревом металла : магистерская диссертация / Enhanced chamber furnace with automatically metal heating

Мирошниченко, А. С., Miroshnichenko, A. S. January 2015 (has links)
Камерная нагревательная печь усовершенствована путем реконструкции каркаса, применением новых теплоизоляционных материалов, использованием новых газовых горелок, работающих в импульсном режиме, и оснащенных системой автоматики. Решена задача нагрева массы металла до заданной температуры. Рассмотрен импульсный нагрев этой массы по заданной программе. Проведен тепловой расчет печи, гидравлические расчеты газопроводов, воздухопроводов, тракта дымовых газов, дана оценка экономической эффективности. Приведено описание системы автоматики. / A chamber furnace has been renovated with using some new technologies, as well as: reconstruction of the skeleton, using new thermoinsulation materials and installation of new gas burners operating at pulse mode with automatical control system. A task of metal mass heating up to the given temperature was solved. Heating processes at the pulse mode with set program was considered. The thermal calculation of furnace, hydraulic calculations of gas pipelines, air and flue gases supply systems were held. Economical efficiency estimation was given. Automatical control system was described.

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