Com o constante desenvolvimento das áreas urbanas e aumento do consumo energético destinado a conforto térmico, um estudo foi realizado para formulação de uma metodologia de análise termoeconômica de sistemas distritais de resfriamento. O objetivo principal é descrever uma metodologia referente à implantação de sistemas distritais no Brasil, por sua vez, o objetivo secundário é aplicar a metodologia no estado de São Paulo, analisando as premissas utilizadas na metodologia. Primeiramente, apresentou-se uma visão geral e revisão de literatura dos sistemas de aquecimento e resfriamento distrital, indicando suas vantagens e desvantagens, bem como as diversas aplicações e desafios para sua implantação. Aplicações no cenário mundial foram expostas e analisadas, demonstrando que sua utilização em diversos países se estende por décadas. As principais vantagens observadas nas aplicações existentes estão relacionadas a maior eficiência energética e exergética global, redução das emissões de gases poluentes e confiabilidade do sistema. Por fim, a metodologia aplicada está apresentada em cinco etapas, de forma ordenada, baseando-se nas etapas de um projeto de sistemas distritais. Seu resultado é baseado em rotinas, simulações de processos e procedimentos de otimização, bem como aplicação de indicadores energéticos. Ao final das etapas e seu desenvolvimento matemático obtém-se um estudo preliminar de viabilidade da implantação de um sistema distrital. O estudo de caso apresentado aplica a metodologia para a cidade de São Paulo buscando descrever com detalhamento as premissas e etapas descritas. / The constant development of urban areas and increased energy consumption for thermal comfort encourage studies that formulate a methodology for thermoeconomic analysis of district cooling systems. The main objective is to describe a thermoeconomic methodology related to the implementation of district systems in Brazil. The secondary objective is to apply the methodology in the state of São Paulo, analyzing the premises used in the methodology. At first, an overview and literature review of district heating and cooling systems was presented, indicating their advantages and disadvantages, just as the various applications and challenges for their implementation. Applications on the world stage have been introduced and analyzed, demonstrating that their use in several countries extends for decades. The main advantages observed in the existing applications are related to global energy and exergy efficiency, reduction in greenhouse gases and reliability of the systems. Finally, the applied methodology is presented in five steps in an orderly manner based on the steps of a district system project. Its result is based on routines, process simulations and optimization procedures, as well as application of energy indicators. At the end of the steps and their mathematical development a preliminary study of the feasibility of the implantation of a district system is obtained. The present case study applies the methodology for the city of São Paulo and describe in detail the premises and steps.

More electric aircraft systems, high power avionics, and a reduction in heat sink capacity have placed a larger emphasis on correctly satisfying aircraft thermal management requirements during conceptual design. Thermal management systems must be capable of dealing with these rising heat loads, while simultaneously meeting mission performance. Since all subsystem power and cooling requirements are ultimately traced back to the engine, the growing interactions between the propulsion and thermal management systems are becoming more significant. As a result, it is necessary to consider their integrated performance during the conceptual design of the aircraft gas turbine engine cycle to ensure that thermal requirements are met. This can be accomplished by using thermodynamic modeling and simulation to investigate the subsystem interactions while conducting the necessary design trades to establish the engine cycle. As the foundation for this research, a parsimonious, transparent thermodynamic model of propulsion and thermal management systems performance was created with a focus on capturing the physics that have the largest impact on propulsion design choices. A key aspect of this approach is the incorporation of physics-based formulations involving the concurrent usage of the first and second laws of thermodynamics to achieve a clearer view of the component-level losses. This is facilitated by the direct prediction of the exergy destruction distribution throughout the integrated system and the resulting quantification of available work losses over the time history of the mission. The characterization of the thermodynamic irreversibility distribution helps give the designer an absolute and consistent view of the tradeoffs associated with the design of the system. Consequently, this leads directly to the question of the optimal allocation of irreversibility across each of the components. An irreversibility allocation approach based on the economic concept of resource allocation is demonstrated for a canonical propulsion and thermal management systems architecture. By posing the problem in economic terms, exergy destruction is treated as a true common currency to barter for improved efficiency, cost, and performance. This then enables the propulsion systems designer to better fulfill system-level requirements and to create a system more robust to future requirements.

A significant part of world energy consumption balance, approx. 40 %, is utilized in buildings. Maintenance of comfortable conditions and improvement in the living, working or recreational environment is a desire for every human. Therefore it is no surprise that there has been a sudden increase in scientific research in the field of building’ energy efficiency. Despite the relevance of the problem there is no sustaining methodology for evaluating building’ energy efficiency by applying sustainable energy development approach. The majority of the researchers don’t assess different potential of the analyzed energy flows nor systems operational regimes. The aim of the work is to evaluate the possibilities for applying exergetical process and system integration method in the design, operation and normalization of the office building service systems: to prepare design solutions that increase buildings’ service systems’ thermodynamical efficiency and covers individual processes and elements’ chain systems. The thesis is divided into the introduction and three main chapters, conclusions, a list of literature and a list of publications. In this work the building service systems’ analysis incorporates three interconnected methods: system analysis, life cycle and thermodynamical analysis. Application of system analyses enables an estimation of service system’s elements (subsystems) and their interconnections. Life cycle analysis allows estimation of total exergy demand through the... [to full text] / Ženklią dalį pasauliniame galutinės energijos vartojimo balanse, apie 40 %, užima energijos dalis, suvartojama pastatuose. Komfortinių sąlygų palaikymas ir gerinimas gyvenamojoje, darbo ar poilsio aplinkoje yra natūralus kiekvieno žmogaus poreikis. Pastaruoju metu stebimas ryškus mokslinių tyrimų suaktyvėjimas didininat energijos vartojimo pastatuose efektyvumą. Nepaisant aktualios problematikos, nuoseklios, darnia energetikos plėtra grindžiamos pastatų energetinio efektyvumo vertinimo metodikos iki šiol nėra. Daugelio tyrėjų naudojami metodai neįvertina skirtingų analizuojamų energijos srautų kokybinių potencialų, nekreipiamas dėmesys į skirtingus sistemų veikimo režimus jų eksploatavimo metu. Darbo tikslas – įvertinti galimybes taikyti procesų ir sistemų integracijos metodą viešųjų pastatų mikroklimato sistemų projektavime, naudojime bei normavime, sukuriant individualius procesus ir visą įrenginių sistemą aprėpiantį priemonių kompleksą, kurio dėka būtų padidintas energijos vartojimo pastate termodinaminis naudingumas. Disertaciją sudaro įvadas, 3 skyriai, pagrindinės išvados, naudotos literatūros sąrašas. Disertaciniame darbe pastato inžinerinių sistemų tyrimui panaudoti trys metodai: sisteminė analizė, gyvavimo ciklo analizė ir termodinaminė (ekserginė) analizė. Sisteminės analizės naudojimas leidžia apibrėžti pastato inžinerinių sistemų elementus bei jų tarpusavio ryšius. Pasitelkus gyvavimo ciklo analizę nustatomi eksergijos poreikiai per visą sistemos gyvavimo... [toliau žr. visą tekstą]

The dissertation investigates the issues of efficient energy use in building engineering systems possibilities by applying processes integration. Indoor climate formation systems are indicated as signally energy use building engineering systems. Traditional methods for evaluation of heat transfer in heat exchangers tender limited solutions for efficiency use of energy in them. The main object of dissertation is to evaluate processes integration method application possibilities for determination and improving of public buildings engineering systems. The dissertation also focuses on combine the possibilities of processes integration in building engineering systems with minimizing exergy streams in the systems. The paper approaches a few major tasks: determination of problematic building engineering systems, equipment and processes by viewpoint of energy efficiency, analysis of ventilation design solutions, creation of algorithm for exergy input minimizing in building engineering systems processes by combination of thermodynamical and Pinch analysis methods. The dissertation consists of four parts including Introduction, 4 chapters, Conclusions and References. The introduction reveals the investigated problem, importance of the thesis and the object of research and describes the purpose and tasks of the paper, research methodology, scientific novelty, the practical significance of results examined in the paper and defended statements. The introduction ends in presenting the... [to full text] / Disertacijoje nagrinėjamos procesų integracijos metodo taikymo galimybės sprendžiant efektyvaus energijos vartojimo pastatų inžinerinėse sistemose problemas. Tarp pastato inžinerinių sistemų darbe išskiriamos ženkliau energiją naudojančios, mikroklimatą pastatuose formuojančios sistemos. Klasikiniai tyrimo metodai, skirti šilumos mainams šilumokaičiuose, kurie atlieka šilumos perdavimo funkciją, nagrinėti pateikia gana ribotus sprendinius, kaip efektyviai naudoti energiją juose. Pagrindinis disertacijos tikslas – įvertinti procesų integravimo metodo taikymo galimybes viešųjų pastatų inžinerinių sistemų termodinaminiam efektyvumui nustatyti ir gerinti. Disertacijoje taip pat siekiama derinti procesų integracijos galimybes inžinerinėse sistemose siekiant minimizuoti eksergijos srautus jose. Darbe sprendžiami keli pagrindiniai uždaviniai: probleminių, energinio efektyvumo požiūriu, pastato inžinerinių sistemų, įrenginių ir procesų jose nustatymas, vėdinimo sistemų projektinių sprendimų ypatybių nustatymas, algoritmo, skirto procesų eksergijos sąnaudoms mažinti pastato inžinerinėse sistemose sudarymas derinant termodinaminės ir Pinch analizės metodus. Disertaciją sudaro įvadas, keturi skyriai, rezultatų apibendrinimas, naudotos literatūros ir autorės publikacijų disertacijos tema sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas... [toliau žr. visą tekstą]

Disertacijoje nagrinėjamos procesų integracijos metodo taikymo galimybės sprendžiant efektyvaus energijos vartojimo pastatų inžinerinėse sistemose problemas. Tarp pastato inžinerinių sistemų darbe išskiriamos ženkliau energiją naudojančios, mikroklimatą pastatuose formuojančios sistemos. Klasikiniai tyrimo metodai, skirti šilumos mainams šilumokaičiuose, kurie atlieka šilumos perdavimo funkciją, nagrinėti pateikia gana ribotus sprendinius, kaip efektyviai naudoti energiją juose. Pagrindinis disertacijos tikslas – įvertinti procesų integravimo metodo taikymo galimybes viešųjų pastatų inžinerinių sistemų termodinaminiam efektyvumui nustatyti ir gerinti. Disertacijoje taip pat siekiama derinti procesų integracijos galimybes inžinerinėse sistemose siekiant minimizuoti eksergijos srautus jose. Darbe sprendžiami keli pagrindiniai uždaviniai: probleminių, energinio efektyvumo požiūriu, pastato inžinerinių sistemų, įrenginių ir procesų jose nustatymas, vėdinimo sistemų projektinių sprendimų ypatybių nustatymas, algoritmo, skirto procesų eksergijos sąnaudoms mažinti pastato inžinerinėse sistemose sudarymas derinant termodinaminės ir Pinch analizės metodus. Disertaciją sudaro įvadas, keturi skyriai, rezultatų apibendrinimas, naudotos literatūros ir autorės publikacijų disertacijos tema sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas... [toliau žr. visą tekstą] / The dissertation investigates the issues of efficient energy use in building engineering systems possibilities by applying processes integration. Indoor climate formation systems are indicated as signally energy use building engineering systems. Traditional methods for evaluation of heat transfer in heat exchangers tender limited solutions for efficiency use of energy in them. The main object of dissertation is to evaluate processes integration method application possibilities for determination and improving of public buildings engineering systems. The dissertation also focuses on combine the possibilities of processes integration in building engineering systems with minimizing exergy streams in the systems. The paper approaches a few major tasks: determination of problematic building engineering systems, equipment and processes by viewpoint of energy efficiency, analysis of ventilation design solutions, creation of algorithm for exergy input minimizing in building engineering systems processes by combination of thermodynamical and Pinch analysis methods. The dissertation consists of four parts including Introduction, 4 chapters, Conclusions and References. The introduction reveals the investigated problem, importance of the thesis and the object of research and describes the purpose and tasks of the paper, research methodology, scientific novelty, the practical significance of results examined in the paper and defended statements. The introduction ends in presenting the... [to full text]

Na atualidade, a geração de eletricidade e a produção de etanol de segunda geração a partir de materiais lignocelulósicos se apresentam como uma alternativa de desenvolvimento tecnológico no setor sucroenergético. Não obstante, a introdução de novos processos produtivos representa um verdadeiro desafio devido à complexidade e diversidade das rotas tecnológicas alternativas que podem ser avaliadas. Além disso, existem fatores econômicos e ambientais, que devem ser considerados durante o desenvolvimento e consolidação destas novas configurações. Nesse sentido, o presente trabalho tem como objetivo desenvolver uma metodologia para realizar a hierarquização exergética e exergo-ambiental de processos para obtenção de etanol e eletricidade a partir da cana-de-açúcar em distintas configurações de biorrefinarias. Para este fim, dados técnicos de operação foram adotados nas rotas tecnológicas envolvidas, bem como os aspectos ambientais da utilização destes sistemas. Os modelos propostos avaliaram as rotas Convencional (Caso 1), Bioquímica (Caso 2) e Termoquímica (Caso 3), utilizando programas de simulação e ferramentas matemáticas para simular estes processos. Ainda, a integração dos processos e diferentes usos para o bagaço excedente foram estudados, junto com diversos métodos de pré-tratamento visando à otimização e hierarquização destas rotas. O resultado final indicou configurações ótimas que permitiram a hierarquização em termos do índice exergético de renovabilidade dos processos de produção das rotas analisadas. Desse modo a rota convencional otimizada apresentou a máxima eficiência exergética dos processos e, por tanto, o menor custo exergético unitário médio das plataformas avaliadas. Ao passo que a rota bioquímica foi o sistema que promoveu um incremento de 28,58 % e 82,87 % na produção de etanol, quando comparado com o Caso 1 e o Caso 3, respectivamente. Além disso, a rota termoquímica apresentou a configuração com a maior taxa de geração de eletricidade excedente (214,98 kWh/TC). Em relação aos resultados do impacto ambiental das rotas tecnológicas, encontrou-se que a configuração mais sustentável foi a plataforma bioquímica, apresentando as menores taxas de emissões globais de CO2 (131,45 gCO2/MJ produtos). / Currently, electricity generation and second-generation bioethanol production from lignocellulosic materials represent technological alternatives in the sugar-energy sector. Nevertheless, the introduction of new production processes represents a real challenge due to the complexity and diversity of the technological routes that can be evaluated. In addition, there are economic and environmental factors that must be considered during the development and consolidation of these new configurations. Accordingly, this project aims to develop a methodology to perform the exergy and exergo-environmental analysis, evaluation and ranking of processes in order to obtain ethanol and electricity from sugarcane in different biorefinery configurations. Hence, operating technical data of each technological route were adopted as well as the environmental aspects of using these systems. The proposed models assessed the Conventional (Case 1), Biochemical (Case 2) and Thermochemical (Case 3) routes using simulation programs and mathematical tools to simulate the ethanol production and electricity generation. Furthermore, the process integration and different uses for the excess bagasse were studied with various pretreatment methods aiming the optimizing and ranking of routes. The results indicated optimal settings that allowed the ranking in terms of the environmental exergy indicator \"renewability\" of the production processes for analyzed routes. In this way, the optimized conventional route presented the maximum exergy efficiency of the processes, therefore the lowest exergetic cost average of the evaluated platforms. While the biochemical route was the system that promoted an increase of 28.58 % and 82.87% in the ethanol production, when compared to Case 1 and Case 3, respectively. In addition, the thermochemical route presented the configuration with the highest power generation rate exceeding (214.98 kWh/TC). Concerning, the environmental impact results, it was found that the most sustainable configuration was the biochemical platform, which presented the lowest overall CO2 emissions rates (131.45 gCO2/MJ products).

O processamento de petróleo e seus derivados é analisado pela aplicação combinada e sistemática da Primeira e da Segunda Lei da Termodinâmica, análise exergética, permitindo a localização dos principais processos destruidores da capacidade de realização de trabalho ao longo da cadeia de processamento. Após a localização das irreversibilidades, diversas opções para melhoria dos processos são avaliadas. A exergia consumida nos processos é dividida em renovável e não renovável e posteriormente repartida, junto com as respectivas emissões de CO2, entre as diversas correntes de cada unidade de processamento. Para uma repartição racional dos fluxos exergéticos e de CO2, a análise exergoeconômica foi utilizada. Um sistema, que permite interações cíclicas entre a cadeia produtiva dos principais combustíveis utilizados no Brasil e a produção de eletricidade, foi elaborado a fim de permitir uma comparação entre os diversos combustíveis levando em consideração toda a cadeia produtiva. Esta comparação está fundamentada no consumo de exergia renovável e não renovável e nas emissões de CO2. Pode-se concluir que o coque de petróleo é o combustível que mais emite CO2, em seguida, encontram-se o carvão e a gasolina. O diesel hidrotratado vem após a gasolina, devido principalmente ao consumo de hidrogênio pelo hidrotratamento. Embora o diesel convencional emita mais SOx e NOx, este diesel exige menos exergia não renovável e emite menos CO2 que o diesel hidrotratado. O hidrogênio, se produzido da forma convencional (reforma a vapor de hidrocarbonetos leves), é o combustível mais intenso em exergia não renovável e com emissão de CO2 próxima ao valor da gasolina e maior que o valor obtido para o diesel convencional. O etanol se mostra uma boa alternativa ao uso dos derivados de petróleo, mesmo considerando configurações típicas para as usinas sucroalcooleiras. / The oil processing is analyzed by the combined and systematic application of the First and Second Laws of Thermodynamics, exergy analysis, allowing the location of the processes responsable for the main destructions of work capability along the processing chain. After the location of irreversibilities, several options for improving processes efficiency are evaluated. The exergy consumed in the processes is divided into renewable and non-renewable and then distributed, along with their CO2 emissions, among the various currents of each processing unit. For a rational distribution of the exergy and CO2 flows, exergoeconomy analysis takes place. A system that allows cyclical interactions between the productive chain of the main fuels used in Brazil and electricity production, is designed to allow the comparison among different fuels taking into account the entire production chain. This comparison is based on renewable and non-renewable exergy consumption and CO2 emissions. It can be concluded that the petroleum coke is the fuel that emits more CO2 followed by coal and gasoline. The hydrotreated diesel comes after gasoline, mainly due to the consumption of hydrogen for hydrotreating. Although conventional diesel emit more NOx and SOx, this diesel requires less non-renewable exergy and emits less CO2 than hydrotreated diesel. Hydrogen, if produced in the conventional way (steam reforming of light hydrocarbons) is the fuel most intense in nonrenewable exergy consumption and has CO2 emission near the value of gasoline and higher than the value obtained for conventional diesel. Ethanol is a good alternative to the use of petroleum derived fuels, even considering typical configurations for sugarcane mills.

<p>U okviru doktorske disertacije predstavljen je<br />razvoj hibridnog modela za ocenjivanje životnog ciklusa<br />proizvoda i procesa. Razvoj hibridnog modela se ogleda<br />kroz unapređenje postojećeg metodskog okvira LCA, te je<br />stoga uključio razvoj svih faza LCA, a koje obuhvataju<br />definisanje cilja i predmeta, inventar životnog ciklusa,<br />ocenjivanje uticaja životnog ciklusa i interpretaciju<br />rezultata. Najznačajnija unapređenja su sprovedena u<br />okviru faza inventara životnog ciklusa i ocenjivanja uticaja<br />životnog ciklusa. Izmene koje se odnose na način<br />prikupljanja podataka, su razvijene zbog uključivanja<br />parametara potrebnih za izračunavanje vrednosti sadržaja<br />eksergije tokova. Unapređenje faze ocenjivanja uticaja<br />životnog ciklusa se ogleda kroz razvoj originalnog pristupa<br />za izračunavanje ukupne potro&scaron;nje eksergije, kroz<br />uključivanje dodatne kategorije uticaja, razvijanje<br />indikatora kategorije uticaja i razvijanje pristupa za<br />izračunavanje karakterizacionih faktora. Sprovedena je i<br />analiza postojećih LCIA metoda, radi izbora adekvatnog<br />metoda u koji će biti uključena dodatna kategorija uticaja,<br />kao i indikator kategorije uticaja, koji zajedno opisuju<br />ukupnu potro&scaron;nju eksergije tokom čitavog životnog<br />ciklusa. Takođe, prilikom razvoja kategorije uticaja su<br />po&scaron;tovani određeni kriterijumi, koje ona mora da zadovolji<br />da bi mogla biti adekvatno uključena u odabrani LCIA<br />metod. Pored toga, bitan deo unapređenja ocenjivanja<br />uticaja životnog ciklusa, leži u razvoju proračuna<br />karakterizacionih faktora. Razvijena dodatna kategorija<br />uticaja nazvana je Ukupna potro&scaron;nja eksergije - UPE, a<br />izražava se preko indikatora MJex. LCIA metod koji je<br />odabran na osnovu SWOT analize u koji je ova dodatna<br />kategorija uticaja uključena je CML metod. Postavljeni<br />hibridni metodski okvir posmatra kompletan životni ciklus,<br />ali i svaki od jediničnih procesa koji uključuju elementarne<br />tokove, odnosno tokove uzete iz prirodnog sistema bez<br />dodatne obrade, kao i tokove proizvoda, odnosno tokovekoji su na neki način izmenjeni od strane pojedinih<br />antropogenih sistema. Izračunavanje sadržaja eksergije i<br />karakterizacionih faktora je sprovedeno kako za<br />elementarne tokove tako i za tokove proizvoda.<br />Funkcionalnost i praktična primenljivost razvijenog<br />hibridnog modela je verifikovana na dva primera, koji su<br />obuvatili proizvodnju laminatnog parketa i međusobnu<br />komparaciju hibridnih baznih predajničkih stanica i<br />konvencionalnih baznih predajničkih stanica. Dobijeni<br />rezultati daju jednu zaista detaljniju i &scaron;iru sliku mehanizma<br />nastanka i izvora negativnih uticaja tokom životnog ciklusa<br />posmatranih industrijskih sistema. Time je potvrđena<br />njegovu praktična primenljivost, kao i ukupni cilj<br />istraživanja. Rezultati istraživanja realizovani u okviru<br />doktorske disertacije, u op&scaron;tem smislu, daju doprinos<br />stvaranju osnove za izdradnju puta ka razvoju i proizvodnji<br />održivih proizvoda i procesa. Razvijeni hibridni model za<br />ocenjivanje životnog ciklusa proizvoda i procesa pruža<br />dodatne informacije, koje mogu biti korisne u procesu<br />dono&scaron;enja odluka na svim nivoima, kako u industriji tako i<br />u državnim institucijama.</p> / <p>This PhD thesis presented the development of a<br />hybrid model for life cycle assessment of products and<br />processes. The development of a hybrid model includes the<br />improvement of the existing methodological LCA<br />framework, and therefore of all phases of the LCA:<br />definition of goal and scope, inventory analysis, life cycle<br />impact assessment and interpretation. The most significant<br />improvements have been made within the inventory<br />analysis and life cycle impact assessment phases.<br />Improvement have been made in relation to the method of<br />data collection, due to the inclusion of parameters for<br />calculation of the exergy content of in- and output flows.<br />Improvement of the life cycle impact assessment phase is<br />reflected through the development of original approach for<br />calculating the total consumption of exergy, through the<br />inclusion of additional impact category, development of<br />indicator for impact category and development of method<br />for calculation of characterization factors. The analysis of<br />existing LCIA methods was performed, in order to choose<br />the appropriate method that will incorporate this additional<br />impact category, as well as an impact category indicator,<br />which together should describe the total consumption of<br />exergy throughout the entire life cycle. Further,<br />development of this impact category have been complied<br />with certain criteria which it must meet in order to be<br />properly incorporated in the chosen LCIA method. Besides<br />this, an important part of improvement of the life cycle<br />impact assessment is the development of method for<br />calculation of characterization factors. Developed<br />additional impact category is named Total exergy<br />consumption, and it&#39;s expressed through indicator of MJex.<br />LCIA method that is chosen based on the performed<br />SWOT analysis and which incorporated this additional<br />impact category is CML method. Developed hybrid<br />methodological framework takes into account the entire life<br />cycle, and each of the unit processes that involves<br />elementary flows (flows taken from the natural system<br />without any further processing), as well as product flows(flows that are in some way altered by certain<br />anthropogenic system). Calculation of exergy and<br />characterization factors was performed for both elementary<br />and product flows.<br />Functionality and practical applicability of the<br />developed hybrid model was verified through two case<br />studies, which are the production of laminate parquet<br />flooring and comparison of hybrid base transceiver stations<br />and conventional base transceiver stations. The obtained<br />results provided more detailed and more broader insight of<br />the mechanism of the generation and source of negative<br />impacts throughout the life cycle of observed industrial<br />systems. Thus, the practical applicability of the developed<br />hybrid model and goal of the research have been<br />confirmed. The results of the research contribute to<br />creation of the foundation for designing a path towards<br />development and manufacturing of sustainable products<br />and processes. The developed hybrid model for the life<br />cycle assessment of products and processes provides<br />additional information that may be useful in decisionmaking<br />process at all levels, within both industry and<br />government institutions.</p>

The change in climate as a consequence of anthropogenic activities is a subject ofmajor concerns. In order to reduce the amount of greenhouse gas emissions inthe atmosphere, the utilization of renewable, fossil-free power generationapplications becomes inevitable. Geothermal and solar energy play a major rolein covering the increased demand for renewable energy sources of today’s andfuture’s society. A special focus hereby lies on the Concentrating Solar Powertechnologies and different geothermal concepts. The costs for producingelectricity through Concentrating Solar Power and therefore Parabolic Trough Collectorsas well as geothermal conversion technologies are still comparatively high. Inorder to minimize these expenses and maximize the cycle’s efficiency, thepossible synergies of a hybridization of these two technologies becomeapparent. This thesis therefore investigates the thermodynamic and economicbenefits and drawbacks of this combination from a global perspective. For that,a Parabolic Trough Collector system is combined with the geothermal conversionconcepts of Direct Steam, Single and Double Flash, Organic Rankine as well asKalina Cycles. The solar integrations under investigation are Superheat,Preheat and Superheat &amp; Reheat of the geothermal fluid. The thermodynamicanalysis focuses on the thermal and utilization efficiencies, as well as therequired Parabolic Trough Collector area. The results indicate that in the caseof the Superheat and Superheat &amp; Reheat setup, the thermal efficiency canbe improved for all geothermal concepts in comparison to their correspondinggeothermal stand-alone case. The Preheat cases, with the major contributionfrom solar energy, are not able to improve the cycle’s thermal efficiencyrelative to the reference setup. From an exergy perspective the findings varysignificantly depending on the applied boundary conditions. Still, almost allcases were able to improve the cycle’s performance compared to the referencecase. For the economic evaluation, the capital investment costs and thelevelized costs of electricity are studied. The capital costs increasesignificantly when adding solar energy to the geothermal cycle. The levelizedelectricity costs could not be lowered for any hybridization case compared tothe reference only-geothermal configurations. The prices vary between20.04 €/MWh and 373.42 €/MWh. When conducting a sensitivity analysison the solar system price and the annual mean irradiance, the Kalina Superheatand Superheat &amp; Reheat, as well as the Organic Rankine Preheathybridizations become cost competitive relative to the reference cases.Concluding, it is important to remark, that even if the hybridization of the ParabolicTrough and the different geothermal concepts makes sense from a thermodynamicperspective, the decisive levelized costs of electricity could not be improved.It is, however, possible that these costs can be further reduced under speciallocal conditions, making the addition of Parabolic Trough solar heat tospecific geothermal concepts favorable.

Afin de faire face aux fortes températures rencontrées par les composantsen aval de la chambre de combustion, des prélèvements d’air plus frais sont réalisésau niveau du compresseur. Cet air alimente les cavités en pied de turbine et refroidiles disques rotor permettant d’assurer le bon fonctionnement de la turbine.Ce manuscrit présente une étude numérique de l’effet de ces écoulements de cavitéau pied de la turbine sur ses performances aérodynamiques. Les phénomènesd’interaction entre l’air de cavité en pied de turbine et l’air de veine principal est unphénomène encore difficilement compris. L’étude de ces phénomènes est réalisée autravers de différentes approches numériques (RANS, LES et LES-LBM) appliquéesà deux configurations pour lesquelles des résultats expérimentaux s ont disponibles.Une première configuration en grille d’aube linéaire en amont de laquelle différentesgéométries d’entrefer (interface entre plateforme rotor et stator) et débits de cavitépouvaient être variés. Une seconde configuration annulaire composée de deux étagesde turbine comprenant les cavités en pied et plus proche d’une configuration industrielle.Les pertes additionnelles associées à l’écoulement de cavité sont mesurées etétudiées à l’aide d’une méthode basée sur l’exergie (bilans d’énergie dans l’objectifde générer du travail). / In order to deal with high temperatures faced by the components downstreamof the combustion chamber, some relatively cold air is bled at the compressor.This air feeds the cavities under the turbine main annulus and cool down the rotordisks ensuring a proper and safe operation of the turbine. This thesis manuscriptintroduces a numerical study of the effect of the cavity flow close to the turbine hubon its aerodynamic performance. The interaction phenomena between the cav-ity andmain annulus flow are not currently fully understood. The study of these phenomenais performed based on different numerical approaches (RANS, LES and LES-LBM)applied to two configurations for which experimental results are avail-able. A linearcascade configuration with an upstream cavity and various rim seal geometries(interface between rotor and stator platform) and cavity flow rate avail-able. Arotating configuration that is a two stage turbine including cavities close to realisticindustrial configurations. Additional losses incurred by the cavity flow are measuredand studied using a method based on exergy (energy balance in the purpose togenerate work).