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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.
41

Desenvolvimento de um módulo computacional para integração energética em plantas sucroalcooleiras na plataforma EMSO

Pina, Eduardo Antonio January 2015 (has links)
Orientador: Prof. Dr. Marcelo Modesto / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2015. / Nas últimas décadas, a integração energética tem se desenvolvido em busca do melhor uso da energia e de recursos em processos industriais e consequente redução do consumo de combustíveis fósseis e dos impactos negativos ao meio ambiente. Dentre os métodos de integração energética, o Método Pinch é, sem dúvida, o mais popular devido a sua simplicidade de implementação e eficiência. Os repetitivos cálculos que a metodologia requer levaram ao desenvolvimento de softwares a fim de agilizar e simplificar o trabalho do projetista. No presente trabalho, foi desenvolvida uma ferramenta computacional para realizar a integração energética de correntes pelo Método Pinch que será utilizada como módulo auxiliar ao programa principal do Projeto Temático FAPESP (Processo Fapesp 2012/04179-2) da Biorrefinaria Virtual de 1ª Geração, a ser desenvolvido na plataforma EMSO. A ferramenta foi desenvolvida na forma de um plug-in, o que facilita o seu uso e distribuição entre vários usuários, na linguagem de programação C++ e fornece ao usuário as metas energéticas, subsidiandoo na elaboração da rede preliminar de trocadores de calor e indicando possibilidades de integração entre correntes que demandem utilidades quentes ou frias. A validação da ferramenta se deu por meio de sua aplicação na integração energética de cinco casos de diferentes níveis de complexidade, sendo um voltado à indústria sucroalcooleira. Os resultados obtidos pelo plug-in foram comparados aos encontrados na literatura e aos da consagrada ferramenta Aspen Energy Analyser®, comprovando-se a consistência e eficiência do plug-in, até mesmo para casos mais complexos, como problemas limiares e de múltiplos pontos Pinch. Como o EMSO não oferece suporte à criação de gráficos, uma planilha suporte em Excel® foi desenvolvida a fim de construir as Curvas Compostas e a Grande Curva Composta, funcionando de modo inteiramente automatizado. / Over the last few decades, heat integration has been developed in search for the better use of energy and resources in industrial processes and eventual reduction in fossil fuels consumption and in the negative environmental impacts. Among the heat integration methods, Pinch technology is without a doubt the most popular one due to its implementation simplicity and efficiency. The monotonous calculations it requires have led to the development of computer software to reduce time and simplify the designer¿s work. In the present study, a computational tool was developed for heat integration through Pinch Analysis to be used as an auxiliary module to the main FAPESP Thematic Project (Fapesp process 2012/04179-2) program of the 1st generation virtual biorefinery, which is being developed on EMSO platform. The computational tool was developed in the form of a plug-in, making its use and distribution among several users easier, in the C++ programming language and it supplies the user with the energy targets, aiding him or her with the design of the preliminary heat transfer network and indicating integration possibilities between hot or cold utility requiring streams. The tool validation was carried out through its application in five case studies of different complexity levels, one of them being related to the sugarcane industry. The plug-in¿s results were compared to the ones gathered from the literature and the ones obtained from the well-stablished heat integration tool Aspen Energy and Analyser®, proving the plug-in¿s consistency and efficiency even for more complex cases such as threshold problems and multiple Pinch problems. As EMSO does not support the design of charts like the Composite Curves and the Grand Composite Curve, an Excel® spreadsheet was developed for this purpose, working on an entirely automated way.
42

Process Integration: Unifying Concepts, Industrial Applications and Software Implementation

Mann, James Gainey 29 October 1999 (has links)
This dissertation is a complete unifying approach to the fundamentals, industrial applications and software implementation of an important branch of process-engineering principles and practice, called process integration. The latter refers to the system-oriented, thermodynamically-based and integrated approaches to the analysis, synthesis and retrofit of process plants, focusing on integrating the use of materials and energy, and minimizing the generation of emissions and wastes. This work extends process integration to include applications for industrial water reuse and wastewater minimization and presents previous developments in a unified manner. The basic ideas of process integration are: (1) to consider first the big picture by looking at the entire manufacturing process as an integrated system; (2) to apply process-engineering principles to key process steps to establish a priori targets for the use of materials and energy, and for the generation of emissions and wastes; and (3) to finalize the details of the process design and retrofit later to support the integrated view, particularly in meeting the established targets. Pinch technology is a set of primarily graphical tools for analyzing a process plant's potential for energy conservation, emission reduction and waste minimization. Here, we identify targets for the minimum consumption of heating and cooling utilities, mass-separating agents, freshwater consumption, wastewater generation and effluent treatment and propose economical grassroots designs and retrofit projects to meet these goals. An emerging alternative approach to pinch technology, especially when analyzing complex water-using operations and effluent-treatment systems, is mathematical optimization. We solve nonlinear programming problems for simple water-using operations through readily available commercial software. However, more complex, nonconvex problems require sophisticated reformulation techniques to guarantee optimality and are the subject of continuing academic and commercial development. This work develops the principles and practice of an environmentally significant breakthrough of process integration, called water-pinch technology. The new technology enables the practicing engineers to maximize water reuse, reduce wastewater generation, and minimize effluent treatment through pinch technology and mathematical optimization. It applies the technology in an industrial water-reuse demonstration project in a petrochemical complex in Taiwan, increasing the average water reuse (and thus reducing the wastewater treatment) in the five manufacturing facilities from 18.6% to 37%. This dissertation presents complete conceptual and software developments to unify the known branches of process integration, such as heat and mass integration, and wastewater minimization, and explores new frontiers of applications to greatly simplify the tools of process integration for practicing engineers. / Ph. D.
43

Análise do circuito de água em processo de fabricação de papel imprensa integrada com produção de pastas termomecânicas. / Analysis of the water circuit of an integrated newsprint and thermomechanical pulp manufacturing process.

Hamaguchi, Marcelo 10 September 2007 (has links)
A indústria de papel e celulose passa por constantes desafios para solucionar problemas relacionados ao alto consumo de água industrial. Uma alternativa é utilizar ferramentas como a Integração de Processos, onde é possível aplicar técnicas gráficas como o \"Water Pinch\" ou técnicas com programação matemática para otimizar o circuito de água. Para contribuir com o setor, as técnicas foram aplicadas no presente trabalho utilizando-se dados reais coletados em uma unidade produtora de polpa termomecânica e papel imprensa. Com os dados, um caso base em um simulador foi desenvolvido para iniciar a análise por Integração de Processos. A análise é baseada no aproveitamento das correntes de águas residuais em outras etapas do processo sob restrições na concentração limite de contaminantes, especificamente finos e sólidos dissolvidos. Diferentemente dos trabalhos apresentados na literatura que alegam que a solução encontrada trata-se de valores otimizados, os resultados mostram que os valores encontrados através da programação matemática e do método Pinch são teoricamente corretos, porém, quando novamente simuladas sob estas novas condições obtidas por Integração de Processos, as condições operacionais da unidade industrial mostram-se inadequadas. As concentrações limites de contaminantes previamente estabelecidos pelas técnicas utilizadas são frequentemente ultrapassadas nos resultados de recálculo por simulação, e portanto, as soluções de Integração de Processos devem ser corrigidas antes de implantação. Por isso, os valores previstos, por exemplo, de redução de consumo de até 38% no projeto realístico atinge o valor de 23%, o que ainda é um bom resultado. O trabalho ainda mostra que a programação matemática é eficaz e rápida para encontrar soluções com múltiplos contaminantes, enquanto o método Pinch é mais voltado para casos com contaminante simples. / The Pulp and Paper industry has constantly struggled to solve problems related to high water consumption. One alternative is to use tools like Process Integration, where graphical methods and mathematical programming can be applied to optimize the water circuit. To contribute to the Pulp and Paper sector, the methods were applied in the present work using real process data that have been collected in an integrated thermomechanical and newsprint mill. With these data, a base case simulation was developed to initiate the analysis by Process Integration. The analysis is based on residual water reuse in other process stages under propriety constraints like contaminants concentration limits, specifically the dissolved solids and fine fibers. Differently from works presented in the references that claim that solutions found are optimized values, the results of this work show that values found by mathematical programming and pinch method are theoretically correct, however, the operational conditions of the mill become inadequate when simulated under new conditions achieved by Process Integration. The concentration limits of contaminants previously established for the methods have their values frequently exceed after recalculation by simulation, and thus, the solutions by Process Integration must be corrected before using them. So, if the predicted value for reduction of fresh water consumption is, for example, 38%, in the realistic project this value will reach only 23%, which is still a good result. The work also shows that mathematical programming is efficient to find solutions when there are multiple contaminants, while pinch method is more adequate for those cases with single contaminant.
44

Étude de la régulation post-transcriptionnelle de l’expression des gènes par la protéine de liaison à l’ARN IMP-2 au cours de la myogenèse / Post-transcriptional regulation of gene expression by IMP-2 during myogenesis.

Boudoukha, Selim 25 November 2011 (has links)
Les rhabdomyosarcomes embryonnaires et aléolaires (RMS) appartiennent aux tumeurs des tissus mous les plus fréquentes chez les enfants dont elles représentent 2/3 des cas. Plusieurs données suggèrent que la dérégulation des cellules progénitrices du muscle squelettique pourrait jouer un rôle dans l'émergence des cellules de RMS qui ont aussi bien perdu le contrôle de la régulation de la prolifération cellulaire que la capacité à se différencier.Néanmoins les mécanismes de développement des RMS restent à caractériser. La famille des IMPs et notamment IMP-2, protéines liant les ARN, sont à la fois fortement exprimées dans le muscle en régénération in vivo mais aussi dans les cellules de RMS.Au cours de ma thèse, j’ai pu mettre en évidence le rôle d’IMP-2 dans la motilité des cellules de RMS et dans les cellules musculaires ainsi que dans le contrôle de l’intégrité du cytosquelette de microtubules (MTs) et dans le remodelage des adhésions focales. En effet, IMP-2 est impliqué à la fois dans la régulation de l’expression de MuRF-3, une protéine lié àla stabilisation des MTs et de Pinch-2, un important médiateur de l’adhésion cellulaire. / The RNA-binding proteins IMPs (IGF-II mRNA binding protein) first discovered in rhabdomyosarcoma cells (RMS) are expressed during embryonic development but their expression is decreased in adult tissues.We showed that IMPs and particularly IMP-2 are strongly expressed in mouse myoblatsts, during early regeneration of skeletal muscle in vivo and in and RMS. IMP-2 loss of function experiments using siRNA have shown that IMP-2 is necessary for microtubules stability(MTs), cell motility and invasion of myoblasts and RMS.Expression of IMP-2 specifically increases MTs stability by an enrichment of detyrosinated tubulin Glu-tubulin. Detyrosination is indispensable for myogenic differentiation and plays substantial role in tumor growth. Additionaly, MTs stabilization play an important role in focal adhesion remodeling, in cytoskeleton integrity, cell adhesion and cell motility.To get new insight into molecular mechanism underlying the function of IMP-2 in MTs stability and cell motility, full ranscriptome analysis was performed between IMP-2 knockdown (KD) myoblasts and control myoblatsts. We have further shown that IMP-2 controls the mRNA levels of many important mediators of cell adhesion such as PINCH-2, as well as multiple cytoskeleton remodeling, such as MuRF-3.We have identified a number of functionally relevant protein partners of IMP-2.Moreover subsequent RNAi screens have revealed the importance of IMP-2 regulated transcripts involved in cell motility and cell adhesion In conclusion, we show that IMP-2 dependent regulation of mRNA such as MuRF3 and PINCH2 largely contributes to the motility –deficient in IMP-2 KD cells. Moreover these results indicate clearly, that further analysis of IMP2 protein partners and RNA targets regulated by IMP-2 will help to characterized the function of IMP-2 and to propose a model of IMP-2 transcriptional regulation of gene expression in myoblasts and RMS cells.
45

MHD simulations of the Reversed Field Pinch

Chahine, Robert 30 November 2017 (has links)
La dynamique des plasmas de fusion par confinement magnétique dans la configuration Reversed Field Pinch (RFP) est ´étudiée en utilisant la description magnétohydrodynamique (MHD) incompressible. Une méthode pseudo-spectrale et une technique de pénalisation en volume sont utilisées pour résoudre le système d’équations dans un cylindre. Les simulations numériques montrent que la pression joue un rôle important dans la dynamique des RFP et ne peut pas être négligée. Ainsi, ß n’est plus le paramètre principal pour décrire la dynamique des RFPs mais plutôt ß’ ∇, un nouveau paramètre qui équivaut le rapport du module de gradient de pression et le module de la force de Lorentz. A un autre niveau, l’effet du changement de la section poloïdale du RFP sur la dynamique est étudié. Les simulations des écoulements RFP ayant le même nombre de Lundquist et des sections différentes (circulaire et elliptique), montrent une grande différence dans les spectres et la diffusion turbulente radiale. Finalement, les écoulements RFP sont utilisés pour étudier l’effet dynamo. Les résultats obtenus montrent que les écoulements RFP sont capables d’amplifier un champ magnétique passif qui aura une tendance à être plus non-linéaire que le champ magnétique du RFP dans les régimes turbulents. / The dynamics of magnetic fusion plasmas in the Reversed Field Pinch (RFP) configuration are studied using an incompressible magnetohydrodynamics (MHD) description. A pseudospectral method combined with a volume penalization method are used to resolve the governing equations in a straight cylinder. Numerical simulations show that the pressure effects on the RFP dynamics cannot be neglected, and thus the _ parameter is not adequate to characterize the importance of pressure in the dynamics. A new parameter, _0r , which is the ratio of the pressure gradient’s magnitude to the Lorentz force’s magnitude, is proposed to be the proper parameter to describe the RFP dynamics. Another investigated influence on the RFP dynamics is the shaping of the poloidal cross-section. Simulations of flows with the same Lundquist number and different cross-sections (circular and elliptic) show a clear change in the spectral behaviour, as well as in the radial turbulent diffusion. Finally, the RFP flows are used to study the dynamo effect. Numerical results show that RFP flows are capable of amplifying a seed magnetic field, which will have tendency to be more nonlinear than the RFP magnetic field in the turbulent regime.
46

Etude d’un système d’amplification de puissance de type multiplicateur de courant dynamique sur l’installation SPHINX du CEA Gramat / Study of a Dynamic Load Current Multiplier system on the SPHINX facility of the CEA Gramat

Maysonnave, Thomas 20 December 2013 (has links)
Depuis plusieurs décennies, les générateurs forts courants sont utilisés dans différents domaines comme l’étude des matériaux, la radiographie ou la fusion par confinement inertiel. Ces générateurs sont capables de délivrer des impulsions de courant de plusieurs millions d’ampères avec des fronts de montée inférieurs à la microseconde. Plusieurs projets à travers le monde ont, aujourd’hui, pour but d’améliorer encore et encore le gradient de courant des impulsions transmises à la charge. De nombreux schémas d’amplificateurs de puissance, dont le rôle est de jouer à la fois sur l’amplitude du courant de charge et sur son temps de montée, ont ainsi été testés. Le multiplicateur de courant dynamique (DLCM pour Dynamic Load Current Multiplier) fait partie de ces concepts novateurs permettant de contourner les limitations des générateurs de puissances pulsées actuels. Il est composé d’un réseau d’électrodes (servant d’autotransformateur), d’un extrudeur de flux dynamique (basé sur l’implosion d’un réseau de fils cylindrique) et d’un commutateur à fermeture sous vide. Dans la thèse, le principe de fonctionnement du DLCM est analysé d’un point de vue théorique par le biais de simulations de type circuits électriques et magnétohydrodynamiques. Une étude spécifique portant sur l’organe principal du DLCM est réalisée. Il s‘agit du commutateur à fermeture sous vide. Ainsi, après une phase de dimensionnement à l’aide d’outils de simulations électrostatiques, deux versions de commutateurs sont validées expérimentalement dans des conditions proches de celles d’un tir très fort courant. Enfin, des tirs sur le générateur SPHINX du CEA Gramat, capable de délivrer une impulsion de courant de 6MA en 800ns (sur charge Z-pinch), sont exposés pour retracer l’évolution du dispositif. Les résultats probants obtenus permettent, au final, de valider le concept DLCM connecté à une charge de type compression isentropique. / For several decades, high power generators are used in various fields such as materials research, radiography or inertial confinement fusion. These generators are capable of delivering current pulses of several millions of amperes with rise times below 1 microsecond. Several projects around the world are, today, trying to improve again and again the current gradient of pulses delivered to the load. Many concepts of power amplifiers, whose role is to optimize both the amplitude of the load current and its rise time, were tested. The Dynamic Load Current Multiplier (DLCM) is one of those innovating concepts used to overcome the existing pulsed power generators limitations. It is made up of concentric electrodes (for autotransformer), a dynamic flux extruder (based on the implosion of cylindrical wire array) and a vacuum closing switch. In this these, the operating principle of the DLCM is theoretically analyzed through electrical and magneto hydrodynamic simulations. A specific study of the DLCM key component is performed. This is the vacuum closing switch. Thus, after a design phase using electrostatic simulation tools, two versions of switches are experimentally validated in conditions similar to those of a very high current shot. Finally, shots on the SPHINX facility located at the CEA Gramat, capable of delivering a current pulse of 6MA in 800ns (on Z-pinch load), are exposed to trace the evolution of this device. The convincing results are used, ultimately, to validate the DLCM concept connected to an isentropic compression experiment load.
47

Méthodologie d’optimisation hybride (Exergie/Pinch) et application aux procédés industriels / Hybrid optimization methodology (Exergy/Pinch) and application to industrial processes

Bou Malham, Christelle 07 December 2018 (has links)
Dans la perspective du présent scénario énergétique, ce travail de thèse propose une méthodologie qui associe la méthode du pincement à l’analyse exergétique de manière à dépasser leurs limitations individuelles aboutissant à une conception améliorée aux deux niveaux : paramètres opératoires et topologie. Une méthodologie globale, consistant à hybrider les deux méthodes thermodynamiques dans une approche entrelacée avec des règles heuristiques et une optimisation numérique, est donc évoquée. À l'aide de nouveaux critères d'optimisation basés sur l’exergie, l'analyse exergétique est utilisée non seulement pour évaluer les pertes d’exergie mais également pour guider les améliorations potentielles des conditions de fonctionnement et de structure des procédés industriels. En plus, au lieu de considérer uniquement l’intégration de la chaleur pour satisfaire des besoins existants, la méthodologie proposée étend la méthode de pincement pour inclure d’autres formes d’exergie récupérables et exploiter de nouvelles voies de synergie via des systèmes de conversion. Après avoir présenté les lignes directrices de la méthodologie proposée, l’approche est démontrée sur deux systèmes industriels, un procédé d’hydrotraitement de gasoil sous vide et un procédé de liquéfaction de gaz naturel. L’application du cadre méthodologique à des processus réalistes a montré comment ajuster les conditions opératoires de chaque procédé et comment mettre en œuvre des systèmes de conversion générant des économies d’énergie substantielles. / In the perspective of the prevailing and alarming energy scene, this doctoral work puts forward a methodology that couples pinch and exergy analysis in a way to surpass their individual limitations in the aim of generating optimal operating conditions and topology for industrial processes. A global methodology, a hybrid of the two thermodynamic methods in an intertwined approach with heuristic rules and numerical optimization, is therefore evoked. Using new optimizing exergy-based criteria, exergy analysis is used not only to assess the exergy losses but also to guide the potential improvements in industrial processes structure and operating conditions. And while pinch analysis considers only heat integration to satisfy existent needs, the proposed methodology allows including other forms of recoverable exergy and explores new synergy pathways through conversion systems. After exhibiting the guidelines of the proposed methodology, the entire approach is demonstrated on two industrial systems, a vacuum gasoil hydrotreating process and a natural gas liquefaction process. The application of the methodological framework on realistic processes demonstrated how to adjust each process operating conditions and how to implement conversion systems ensuing substantial energy savings.
48

Evaluation of possibilities for processes integration in ventilation equipment / Procesų integravimo vėdinimo įrenginiuose galimybių vertinimas

Misevičiūtė, Violeta 06 February 2012 (has links)
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]
49

Procesų integravimo vėdinimo įrenginiuose galimybių vertinimas / Evaluation of possibilities for processes integration in ventilation equipment

Misevičiūtė, Violeta 06 February 2012 (has links)
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]
50

Desenvolvimento de um programa computacional em Scilab® baseado no método Pinch de integração energética

Resende, Marina Garcia 25 February 2013 (has links)
Made available in DSpace on 2016-06-02T19:56:49Z (GMT). No. of bitstreams: 1 4983.pdf: 2300350 bytes, checksum: d86b92bce6ba28c7a9e288585bab12f1 (MD5) Previous issue date: 2013-02-25 / Universidade Federal de Sao Carlos / The increasing concern about environmental impacts caused by human activities has led scientists to look for ways to settle the situation. As regards chemical industries, one of the main focuses of this concern is the energy saving. Over several studies down the years, the idea of Pinch technology has risen up as one of the main and most efficient techniques of energy integration so far. It is based on the division of the problem into two systems starting from Pinch point, in which retrofits and/or synthesis of heat exchanger networks are realized separately, grounded on Thermodynamics principles. Nevertheless, at times, the calculation needed for this methodology can be tedious and time consuming. For that effect, there is the need to use software s to execute faster the initial calculations that Pinch method demands, in order to make it easier the future project of heat exchanger networks. The purpose of this work was to create a computer program in Scilab® language, for application of basic principles of Pinch analysis. Five case studies were presented to illustrate and test the performance of the new program. Furthermore, some of the main properties of this technique are presented, proving to be very interesting and inspiring for the rising or new researches in the area. From this work, it can be concluded that Pinch analysis is a relatively simple and efficient way to the retrofit and synthesis of heat exchanger networks, being able to be used in the solution of a several range of problems. Thus, energy savings associated to capital savings are possible, making it easier to exist a quality deal between the environment and profitability of chemical industries. Besides, the new program implemented in Scilab® has shown up to be a really efficient tool in the application of the method, facilitating the learning of users recent presented to Pinch technology and also being useful to more experienced designers, presenting satisfactory results regarding energy optimization of processes. / A crescente preocupação com impactos ambientais causados por atividades humanas tem levado cientistas a buscar alternativas para amenizar a situação. No que se refere a indústrias químicas, um dos focos principais dessa preocupação é a economia de energia. Através de vários estudos realizados ao longo dos anos, surgiu então a ideia da tecnologia Pinch, uma das principais e mais eficientes técnicas de integração energética existente. É baseada na divisão do problema em dois sistemas através do ponto Pinch, nos quais são realizados reprojetos e/ou sínteses de Redes de Trocadores de Calor (RTC) separadamente, fundamentados em princípios da Termodinâmica. No entanto, por vezes, os cálculos necessários a essa metodologia podem ser demorados e tediosos. Por esta razão, há a necessidade do uso de softwares para efetuar mais rapidamente os cálculos iniciais do método Pinch, facilitando, então, o futuro projeto de redes de trocadores de calor. O objetivo deste trabalho foi criar um programa computacional em linguagem Scilab®, para aplicação dos princípios básicos da análise Pinch. Cinco estudos de caso foram apresentados para ilustrar e testar o desempenho do novo programa. Ademais, são apresentadas algumas das principais propriedades relativas a esta técnica, mostrando-se bastante interessantes e inspiradoras para a realização de novas pesquisas dentro da área. Através deste trabalho, conclui-se que a análise Pinch é uma maneira relativamente simples e eficaz para síntese de RTC, podendo ser utilizada para a resolução de uma vasta gama de problemas. Desta forma, é possível uma recuperação energética aliada à economia de capital, possibilitando um acordo de qualidade entre meio ambiente e lucratividade das indústrias químicas. Ademais, o programa computacional implementado em Scilab® mostrou-se uma ferramenta bastante eficiente para aplicação do método, facilitando o aprendizado da tecnologia Pinch por usuários iniciantes e também sendo útil para projetistas mais experientes, apresentando resultados satisfatórios no que se refere à otimização energética do processo.

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