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A new approach to modelling process and building energy flows in manufacturing industryOates, Michael January 2013 (has links)
Global conservation of energy and material has become a key topic among governments, businesses, local societies and academics. A point made by many on the subject of energy begin by stating the importance of conserving the earth’s natural resources, and the need to reduce greenhouse gas emissions in a bid to reduce global warming. This research is no exception, concentrating on an energy and material intensive sector of the global economy; manufacturing industry. This research formulates a methodology for modelling energy flows between a factory building, its manufacturing process systems and the materials used. The need for such an approach arises from the gap in knowledge between the understanding of energy consumed by factory buildings and process systems in manufacturing industry. Factory buildings are purpose built environments that house manufacturing processes, manufacturing plant, materials and occupants. Modern production lines are designed to optimise the flow of materials throughout a factory; to and from storage, production, assembly and distribution. Manufacturing production systems dictate the shape and size of factory buildings. This can lead to a high proportion of the overall energy consumption to be attributed to building services. The coupling of factory energy flows assists energy managers at both the facility and process levels, in order to identify efficiency improvements and reduce energy use and associated carbon emissions. A better understanding of the overall energy balance of a factory environment will allow energy to be used in a more sustainable manner. Simulation tools are widely used in the disciplines of building design and manufacturing systems engineering. Traditional building energy flow paths are well documented and are handled within dynamic building modelling tools. Globally, manufacturing activities cover a wide field of industrial practice and use a range of simulation software packages such as flow diagramming packages, computational fluid dynamics, discrete event tools, direct coding, optimisation tools etc. The increasing use of simulation makes it difficult for a manufacturing systems analyst to choose a suitable approach for energy modelling. An important aspect of the methodology described in this thesis is the coupling of energy flows that occur internally (within a factory boundary) and externally (outside a factory boundary e.g. weather) in relation to time and location within and around a factory environment. Building modelling tools provide a structured and well defined approach to monitoring energy flows within traditional built environments. The methodology extends the framework of an existing building modelling tool; the International Building Physics Toolbox (IBPT), to include the simulation of manufacturing process systems and material flow within a factory. There is a wide range of manufacturing processes used in industry so the scope of this research is reduced to thermal and electrical processes only. A thermal process is considered to be an extension of a thermal zone (such as a room), as defined in building modelling tools. Two thermal processes are considered; processes that act on a volume of gas (i.e. air) and those that act on a volume of liquid. Material flow is represented in the model by time series. The lumped capacitance method is used to approximate the change in surface temperature of a material in relation to its stored energy, long wave radiation between the material and its surroundings, and convective heat transfer. To validate the use of the IBPT algorithms to model building physics, the results derived by using the IBPT are compared with those derived by using an industry standard trusted building modelling tool called ‘Integrated Environmental Solutions Virtual Environment’ (IES VE), in comparable areas of building modelling. Three industrial case studies have been analysed, and these represent real scenarios from the automotive and aerospace manufacturing industry sectors. Two out of the three case studies include the simulation of the building (fabric and heating system), material flow and manufacturing process systems (air and liquid based). The third case study focuses on process modelling only, with future scope to include the factory building. Data obtained from industrial practice is used to validate the results of energy modelling using the proposed method. Results from the case studies demonstrate the capabilities of the proposed method of modelling factory energy flows and associated energy consumption at both facility and process level. Opportunities to reduce energy use and associated carbon emissions are also identified. The methodology does have some limitations in the form of the number of manufacturing process types represented and the complex nature of modelling real energy flows that occur within factory buildings. However the findings of the research show that an integrated approach to modelling factory energy flows through development of a building modelling framework has real benefits for manufacturing industry. These benefits are very unlikely to be realised by modelling processes and buildings separately, as is the way current modelling methods are carried out by the separate discipline areas of building design and manufacturing systems. Factory energy managers and future factory designs are example areas in which the presented integrated tool would be most beneficial used. Future research within this area could include an extension of the framework to model moisture transfer, the inclusion of further types of manufacturing process systems and further investigation into the coupling of time-driven and event-driven hybrid modelling techniques to simulate material flow both in terms of locality and thermal behaviour.
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Study of Solid State Photocatalysts and other Energy Materials using Synchrotron Radiation2012 September 1900 (has links)
This work presents a spectroscopic and theoretical study of several energy materials using synchrotron-based techniques. Two classes of materials are studied: solids that have reported photocatalytic properties, and lithium compounds that are thought to form during the cycling of
modern battery electrodes.
An overview of synchrotron soft X-ray spectroscopic techniques is presented, along with the theory and procedures associated with performing such measurements. These measurements are compared to density functional theory (DFT) calculations, as implemented by the WIEN2k package, along with a description of the DFT method. Calculated electronic structure is shown to be a useful aid in interpreting the results of X-ray emission and X-ray near-edge absorption measurements (XES and XANES), allowing conclusions about the physical structure and properties of the materials to be reached.
Two photocatalytic systems are outlined, the first of which is a solid solution of GaN and ZnO (GaN:ZnO) that exhibits an unexpected reduction in band gap. By carefully comparing common hybridized features from O, N and Zn core emission lines, a binding energy picture of the valence and conduction bands of GaN:ZnO is constructed, allowing its band gap reduction to be described as a consequence of heterojunctions between predominantly GaN and ZnO regions within the solid solution. This description attempts to resolve controversy in the literature regarding the origin of the band gap reduction, as well as to rule out a hypothesized oxynitride superlattice structure as the explanation.
The second photocatalytic system studied is a carbon nitride derivative, poly(triazine imide) (PTI) that displays high crystallinity and that could be very inexpensive to produce due to its elemental abundance. Through resonant excitation, two inequivalent N sites in PTI can be probed by X-ray emission spectroscopy, indicating the material is not a conjugated polymer like other reported carbon nitrides. The band gap of the system is observed to decrease in response to disordered Li loading, an e ect that is con rmed by DFT calculation. Several potential disorder models of the Li loading of PTI are investigated with DFT force minimization in order to choose a structural candidate capable of producing calculated X-ray spectra that agree with our measurements.
The presented lithium study attempts to use a modern soft X-ray absorption facility to characterize the Li surface by-products inherent to the charge-discharge cycling of a battery electrode. A survey of potential Li compounds was performed using Li K-edge XANES will be compared to DFT calculations and X-ray Raman Scattering measurements performed by collaborators in the future. Correlating measurements of the survey compounds with charge-cycled electrode measurements will be an area for future work.
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Termoelektrický solární generátor / Thermo-electric solar generatorKočvárek, Ondřej January 2008 (has links)
The introduction of this work is devoted to the description of physical principals and condtruction of modern semiconductor thermoelectric transformers. This work describes thein basic characters and the most commonly used materials for thein production. Further, it mentions the basic principals and physical effects that describe the thermoelectric conversion of energy and the nondestructive method for establishing the basic material characteristics of thermoelectric transformers. The substantiv part of this work is the measuring of the material’s characteristics of the accessible thermoelectric elements through the medium of experimental measuring network. The optimal construction of thermoelectric solar generators used for individual thermoelectric elements are designed based on the taken measurements and the evaluation of material’s characteristics of the observed thermoelectric elements.
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Ökobilanzierung im Kontext planerischer Interessen - Bewertungsverfahren für BauprodukteGruhler, Karin, Deilmann, Clemens 23 September 2014 (has links)
Die ökologische Bewertung von Bauteilen stößt in der Praxis auf erhebliche Wissens- und Anwendungsdefizite. Die Komplexität der an Bauteile gestellten Forderungen und die unterschiedlichen Informationsinteressen von Bauherren, Planern und Produzenten erschweren die Entwicklung geeigneter Informations- und Bewertungsmodelle. Eine am IÖR durchgeführte Forschungsarbeit hat die Anwendungsmöglichkeiten der Ökobilanz als Analyse- und Bewertungsinstrument geprüft.
Im Rahmen der Arbeit wurden methodische Probleme untersucht und ein Bewertungsansatz für Bauteile entwickelt. Es wird deutlich, dass die Ergebnisse der Ökobilanz für den Planer von Bedeutung sind, dass er als Entscheidungshilfe jedoch einen inhaltlich breiteren Bewertungsansatz benötigt. Es wird vorgeschlagen, die Bilanz von Bauteilen neben den für eine Ökobilanz typischen Umweltwirkungen um funktionsbezogene, technische, gesundheitsorientierte und wirtschaftliche Aspekte zu erweitern. Des Weiteren wird festgestellt, dass die Bilanzierung von Bauteilen vom methodischen Ansatz her stets eine Kombination aus Produkt- und Betriebsbilanz ist, wobei die betriebliche Bilanzierung aufgrund der langen Nutzungsdauer von Bauprodukten stärker in den Vordergrund rücken sollte.:Tabellenverzeichnis................................................................................VI
Abbildungsverzeichnis...........................................................................VII
Einleitung.................................................................................................1
A Bestimmung eines spezifischen Bilanzansatzes – methodische
Untersuchungen zu Bilanzmodellen.........................................................5
1 Stoffstrombetrachtungen und Ökobilanz – Zusammenhänge...............7
1.1 Stoffstrombetrachtungen – Antwort auf das Umdenken in der
Umweltpolitik...........................................................................................7
1.2 Stoffstrommanagement – Einordnung der Ökobilanz........................7
2 Unterschiedliche Bilanzmodelle im Rahmen von Stoffstrombetrachtungen –
Methodendiskussion..............................................................................11
2.1 Ökobilanzen als Synonym für die Analyse und Bewertung von
Stoff- und Energieflüssen......................................................................11
2.2 Unterschiedliche Bilanzmodelle im Rahmen von Stoffstrombetrachtungen.......................................................................12
2.3 Auswertung der dargestellten Modelle............................................22
3 Produkt- und Betriebs-Ökobilanzen – Detailuntersuchungen.............25
3.1 Ökobilanzen – allgemeine Definition................................................25
3.2 Produkt-Ökobilanzen nach ISO-Norm..............................................25
3.2.1 Festlegung des Zieles und des Untersuchungsrahmens..............28
3.2.2 Sachbilanz....................................................................................29
3.2.3 Wirkungsabschätzung..................................................................29
3.2.4 Auswertung..................................................................................30
3.3 Betriebs-Ökobilanzen......................................................................30
3.4 Produkt- und Betriebs-Ökobilanz im Vergleich.................................32
4 Spezifischer Bilanzansatz für Bauteile................................................34
4.1 Betrachtungsgegenstand Bauteil – Besonderheiten.......................34
4.2 Bestimmung eines spezifischen Bilanzansatzes für Bauteile...........35
B Eingrenzung eines spezifischen Bilanzrahmens – methodische
Untersuchungen zu Betrachtungsinhalten und -grenzen......................39
1 Problembereiche im Rahmen der Produkt-Ökobilanz..........................41
1.1 Zieldefinition....................................................................................41
1.1.1 Funktionale Äquivalenz.................................................................42
1.1.2 Untersuchungsrahmen.................................................................45
1.2 Sachbilanz.......................................................................................52
1.2.1 Input- und Outputgrößen in der Sachbilanz..................................52
1.2.2 Methodische und datenbezogene Probleme.................................54
2 Spezifik des Bauteiles Außenwand im Kontext planerischer
Interessen und Ziele.............................................................................58
2.1 Anforderungen an das Bauteil Außenwand......................................58
2.2 Anforderungen an das Bauen – gesetzliche Bestimmungen,
Verordnungen und Vorschriften.............................................................59
2.3 Interessen und Ziele der Akteursgruppe Planer..............................60
2.4 Eingrenzung eines spezifischen Bilanzrahmens für das Bauteil
Außenwand............................................................................................65
3 Beschreibung des spezifischen Bilanzrahmens...................................69
3.1 Lebenswegphasen..........................................................................69
3.2 Lebenswegkriterien.........................................................................71
3.2.1 Funktionale Anforderungen..........................................................72
3.2.2 Ökologische Anforderungen..........................................................75
3.2.3 Ökonomische Anforderungen........................................................77
C Bilanzbeispiel – Bauteilbewertung im Test.........................................79
1 Außenwandvergleich auf Grundlage ausgewählter Einzelkriterien.....81
1.1 Unterschiedliche Außenwandkonstruktionen – Aufbau und Mindestanforderungen..........................................................................81
1.2 Außenwandvergleich auf Grundlage unterschiedlicher Einzelkriterien ..............................................................................................................82
1.2.1 Bereich Funktion...........................................................................82
1.2.2 Bereich Gesundheit.......................................................................87
1.2.3 Bereich Stoffe/Energie..................................................................92
1.2.4 Bereich Ökonomie.........................................................................99
2 Außenwandvergleich – komplexe Bewertung...................................101
Zusammenfassung..............................................................................105
Anhang A – Spezifischer Bilanzansatz.................................................107
Anhang B – Spezifischer Bilanzrahmen................................................113
Anhang C – Bilanzbeispiel....................................................................117
Literaturverzeichnis.............................................................................123
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