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Found 21 results.

High density power electronics for FC- and ICE-Hybrid Electric Vehicle Powertrains (HOPE)

Das Projekt "High density power electronics for FC- and ICE-Hybrid Electric Vehicle Powertrains (HOPE)" wird vom Umweltbundesamt gefördert und von Siemens AG durchgeführt. Objective: The project HOPE is addressing power electronics. It is based on previous EU research projects like the recently finished FW5 HIMRATE (high-temperature power modules), FW5 PROCURE (high-temperature passive components), and MEDEA+ HOTCAR (high-temperature control electronics) and other EU and national research projects. The general objectives of HOPE are: Cost reduction; meet reliability requirements; reduction of volume and weight. This is a necessity to bring the FC- and ICE-hybrid vehicles to success. WP1 defines specifications common to OEM for FC- and ICE-hybrid vehicle drive systems; Identification of common key parameters (power, voltage, size) that allows consequent standardisation; developing a scalability matrix for power electronic building blocks PEBBs. The power ranges will be much higher than those of e.g. HIMRATE and will go beyond 100 kW electric power. WP2 works out one reference mission profile, which will be taken as the basis for the very extensive reliability tests planned. WP3 is investigating key technologies for PEBBs in every respect: materials, components (active Si- and SiC switches, passive devices, sensors), new solders and alternative joinings, cooling, and EMI shielding. In WP4 three PEBBs will be developed: HDPM (high density power module) which is based on double side liquid cooling of the power semiconductor devices; IML (power mechatronics module), which is based on a lead-frame technology; and SiC-PEBB inverter (silicon carbide semiconductor JFET devices instead of Si devices). WP5 develops a control unit for high-temperature control electronics for the SiC-PEBBs. Finally WP6 works on integrating the new technologies invented in HOPE into powertrain systems and carries out a benchmark tests. All the results achieved in HOPE will be discussed intensively with the proposed Integrated Project HYSIS where the integration work will take place. It is clear from the start that many innovations are necessary to meet the overall goal.

Storage of hydrogen in hydrides

Das Projekt "Storage of hydrogen in hydrides" wird vom Umweltbundesamt gefördert und von Weierstraß-Institut für Angewandte Analysis und Stochastik durchgeführt. Hydrogen is the ideal synthetic fuel to convert chemical energy into electrical energy or into motive power because it is light weight, highly abundant and its oxidation product is vapor of water. Thus its usage helps to reduce the greenhouse gases and it conserves fossile resources. There is even a clean way to produce hydrogen by electrolysis of water by means of photo voltaics (SvW06, VSM05, PMM05). There are various possibilities to store the hydrogen for later use: Liquid and gaseous hydrogen can be stored in a pressure vessel, hydrogen can be adsorped on large surface areas of solids, and finally crystal lattices of metals or other compounds can be used as the storage system, where hydrogen is dissolved either on interstitial or on regular lattice sites by substitution (SvW06, San99). The latter process and its reversal is called hydriding respectively dehydriding. The subject of this proposal is the modeling and simulation of that process. The main problem of a rechargeable lithium-ion battery is likewise a storage problem, because in a rechargeable battery, both the anode and cathode do not directly take part in the electrochemical process that converts chemical energy into electrical energy, rather they act as host systems for the electron spending element, which is here lithium (Li). During the last month the applicant developed and exploited a mathematical model that is capable to capture the storage problem of an iron phosphate (FePO4) cathode, where the Li atoms are stored on interstitial lattice sites (DGJ07).

Litebus-Modular Lightweight Sandwich Bus Concept

Das Projekt "Litebus-Modular Lightweight Sandwich Bus Concept" wird vom Umweltbundesamt gefördert und von Technische Universität Clausthal, Institut für Polymerwerkstoffe und Kunststofftechnik durchgeführt. Die öffentlichen Verkehrsmittel sollen durch technische Neuerungen, etwa bei der Materialauswahl, umweltschonender betrieben werden. Bei den Werkstoffen werden Hybrid-Materialien und Sandwichverbunde aufgrund ihres geringen Gewichts, der hohen Steifigkeit und des guten Crashverhaltens immer wichtiger für den Fahrzeugbau. Im Rahmen des EU-Projektes ging es darum, die bisher übliche Metallbauweise von Bussen durch leichtere Strukturen zu ersetzen. Als neue Materialien für die Karosserie empfehlen sich lasttragende Sandwichverbunde aus faserverstärkten Kunst- und Schaumstoffen. Zwischen zwei Schichten von hochstabilen Kunststoffen wird quasi als mittlere Schicht ein steifer Schaumstoff eingelagert. Solche innovativen Materialkombinationen haben sich im Flugzeugbau oder auch für Windenergieanlagen aufgrund ihrer guten Leichtbaueigenschaften bereits etabliert - und könnten nun auch im Busbau eingesetzt werden. Hauptaufgabe der Clausthaler Wissenschaftler waren die Material- und Prozessauswahl der Busstrukturkomponente. Außerdem arbeiteten sie an deren Gestaltung mit. Die Wahl fiel schließlich auf eine Kombination unterschiedlicher Materialien wie Glas- und Kohlenstofffasern mit Epoxidharz als Matrix sowie einem Strukturschaum als Kernwerkstoff für die Erfüllung der hohen Anforderungen in Bussen. Innerhalb des Gesamtprojekts ist eine Zelle des neuen Busses gebaut und mit Sitzen und Fenstern ausgestattet worden. Zur Überprüfung der Bussicherheit wurde ein Überrolltest durchgeführt. Die Zelle bestand den Test mit, lediglich die äußere der Doppelglasscheiben ging zu Bruch. Alle drei am Projekt beteiligten Busbaufirmen wollen die erarbeiteten Erkenntnisse für folgende Fahrzeuggeneration aufnehmen und verstärkt faserverstärkte Kunststoffe einsetzen. Bei der Entwicklung der Sandwichbauweise für Busse waren Wissenschaftler aus ganz Europa beteiligt gewesen. Die Projektkoordination lag beim INEGI - Instituto de Engenharia Mecanica e Gestao Industrial, Leca do Balio, Protugal.

Integration of routine Aircraft measurements into a Global Observing System (IAGOS)

Das Projekt "Integration of routine Aircraft measurements into a Global Observing System (IAGOS)" wird vom Umweltbundesamt gefördert und von Forschungszentrum Jülich GmbH, Institut für Chemie und Dynamik der Geosphäre durchgeführt. IAGOS is a design study pursuing the preparation of a resilient distributed infrastructure for routine observations of atmospheric composition, aerosols, clouds and contrails on the global scale from commercial in-service aircraft. Observations in the Up per Troposphere and Lower Stratosphere (UTLS) are critical for improving the scientific understanding of chemistry-climate interactions, particularly those associated with the roles of clouds, aerosols and chemical composition. This information is essen tial for improving the scientific basis related to predictions of global climate change and for the assessment of surface air pollution, including the influence of aviation impacts and of emissions from other parts of the world on Europe. In IAGOS, new instrument packages will be developed which include state of the art developments based on the former MOZAIC instrumentation for O3, H2O, CO and NOy/NOx with significant reductions in size and weight. A central element is the certification of the packa ges for installation and deployment on Airbus longrange aircraft and for maintenance in compliance with aeronautical regulations. New instrumentation will be designed for aerosol, cloud particles and for stratospheric water vapour. Another important elem ent is the design of realtime data provision from the new instruments to meteorological services. Finally, IAGOS will establish the logistic and financial boundary conditions for the operation of the new infrastructure and will initiate the dialog betwe en scientific partners, users and airlines interested in supporting the new infrastructure. IAGOS is epected to make a significant step forward in the development of a globally operated in situ ob-servation network for the climate system.

Biological Regulation of Subsoil C-cycling under Field Conditions

Das Projekt "Biological Regulation of Subsoil C-cycling under Field Conditions" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Bodenbiologie durchgeführt. The nature of the microbial communities inhabiting the deeper soil horizons is largely unknown. It is also not clear why subsurface microorganisms do not make faster use of organic compounds under field conditions. The answer could be provided by a reciprocal soil transfer experiment studying the response of transferred soils to fluctuations in microclimate, organic inputs, and soil biota. The subproject P9 will be responsible for the establishment of reciprocal transfer experiments offering a strong link between subgroups interested in organic matter quality, transport of organic substances, as well as functions of the soil microbial community. A single, high molecular weight substrate (13C labelled cellulose) will be applied at two different levels in the pre-experiment to understand the dose-dependent reaction of soil microorganisms in transferred surface and sub-soils. Uniformly 13C labelled beech roots - representing complex substrates - will be used for the main reciprocal soil transfer experiment. We hypothesize that transferring soil cores between subsoil and surface soil as well as addition of labelled cellulose or roots will allow us to evaluate the relative impact of surface/subsurface habitat conditions and resource availability on abundance, function, and diversity of the soil microbial community. The second objective of the subproject is to understand whether minerals buried within different soil compartments (topsoil vs. subsoil) in the field contribute to creation of hot spots of microbial abundance and activity within a period of two to five years. We hypothesize that soil microorganisms colonize organo-mineral complexes depending on their nutritional composition and substrate availability. The existence of micro-habitat specific microbial communities could be important for short term carbon storage (1 to 6 years). The third objective is to understand the biogeography and function of soil microorganisms in different subsoils. Parent material as well as mineral composition might control niche differentiation during soil development. Depending on size and interconnectedness of niches, colonization and survival of soil microbial communities might be different in soils derived from loess, sand, terra fusca, or sandstone. From the methodological point of view, our specific interest is to place community composition into context with soil microbial functions in subsoils. Our subgroup will be responsible for determining the abundance, diversity, und function of soil microorganisms (13C microbial biomass, 13C PLFA, enzyme activities, DNA extraction followed by quantitative PCR). Quantitative PCR will be used to estimate total abundances of bacteria, archaea and fungi as well as abundances of specific groups of bacteria at high taxonomic levels. We will apply taxa specific bacterial primers because classes or phyla might be differentiated into ecological categories on the basis of their life strategies.

Shifts in the climate niche of mammals: evolutionary constraints or adaptation potential?

Das Projekt "Shifts in the climate niche of mammals: evolutionary constraints or adaptation potential?" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Institut für Geo- und Umweltnaturwissenschaften, Abteilung für Biometrie und Umweltsystemanalyse durchgeführt. Predictions of effects of climate change on species distributions assume constant climatic niches. Our current understanding of how climate niches developed through evolution is very limited. This project shall analyse how climate niche of the 5488 mammal species worldwide is related to their phylogenetic position. The hypothesis is that closely related species will also have similar climate niches, indicating climate niche conservation. Based on current distributions and environmental data, we shall quantify the climate niche of each species and compare it to that of its closest relative (sister species). We shall investigate whether climate niche position is similarly phylogenetically constrained as other species traits such as body weight, gestation length or litter size. The huge breadth of mammal ecologies, their highly resolved phylogenetic tree, their high conservation relevance and their relatively well-known geographical distribution make them an ideal study system. In the process of this study, new methodological standards for the analysis of niche evolution will be developed, including randomisation tests, virtual species analysis and character tracing of climate niche position. In the end, we shall be able to specify the adaptation potential to climate change for a large number of species studied.

Innovationsplattform einer grünen, detektierbaren und direkt recycelbaren Lithium-Ionen Batterie

Das Projekt "Innovationsplattform einer grünen, detektierbaren und direkt recycelbaren Lithium-Ionen Batterie" wird vom Umweltbundesamt gefördert und von Pure Devices GmbH durchgeführt. Ziel dieses Teilvorhabens ist die Entwicklung eines Niederfeld Lithium-NMR Sensors zur Detektion von Lithium in den einzelnen Prozessschritten beim Recycling von LIB. Für die Qualitäts- und Prozesskontrolle mittels Protonen-NMR gibt es in der Industrie bereits viele Anwendungen (solid fat content, contactless weight checking, polymer profiling). Eine Prozesskontrolle an Lithium-haltigen Substanzen durch Li-NMR im Niederfeld ist eine neue Anwendung, welche in diesem Projekt implementiert werden soll. Ziel ist es die Lithiumströme im Recycling-Prozess und der Verbleib von Lithium in den einzelnen abgetrennten Komponenten zu verfolgen. Eine solcher Li-NMR Sensor zur Prozesskontrolle ließe sich durch weitere Optimierungen zu einem Produkt weiterentwickeln und ermöglicht so die Etablierung einer weiteren Messmethode zur Lithiumdetektion.

Qualifizierung des Elektronenstrahlschweißens im Dickblechbereich für Anwendungen im Windenergieanlagenbau

Das Projekt "Qualifizierung des Elektronenstrahlschweißens im Dickblechbereich für Anwendungen im Windenergieanlagenbau" wird vom Umweltbundesamt gefördert und von RWTH Aachen University, Institut für Eisenhüttenkunde - IEHK durchgeführt. Due to ecological reasons and because of the need to remain independent from foreign energy suppliers, the power generation in offshore wind parks becomes more and more important in Germany. It is therefore planned to build up approximately 1,300 new offshore wind power plants with a capacity of 6,500 MW near the German coastline until 2020. The structures are installed on the ground of the sea in a water depth that might in some cases reach 50 m. The mechanical loading situation for these structures is characterised by an enormous weight combined with high cyclic stresses resulting from the service loads and the tide. Hence, hot rolled steels with a yield strength of 355 MPa are employed in a maximum thickness of 100 mm. Until now, the required toughness properties for these structural steels and their welds are 40 J at -20 C. However, in a plate thickness of 100 mm, only the submerged arc welding (SAW) process can be used to guarantee such toughness properties, but especially in these heavy plates, submerged arc welding is rather time consuming and consequently more uneconomic compared to other welding techniques. Due to these disadvantages, it can even be expected that only part of the planned power plants will be built up in time as the high welding time of several hours per m causes too many delays. From the point of structural integrity, it can be argued wether a Charpy impact toughness of 40 J is really required, as this criterion is only set based on experiences of mechanical and civil engineers. Thus, it can be concluded that different welding techniques should be regarded as alternatives to SAW in case that the 'real' toughness requirements are less than 40 J at -20 C. Electron beam welding would be a favourable welding process for such heavy plates as even 100 m thick plates can be welded in one single step, but until now the toughness requirements of 40 J have not yet been met. It is therefore the aim of the research project to reinforce the electron beam welding process for the application to heavy plates in offshore wind power plants. To reach this aim, the following tasks are be carried out: - improvement of the electron beam welding process in order to achieve better toughness properties of the welds, - application of reliable fracture mechanics concepts in order to calculate realisitc toughness requirements. With regard to the process, already a this stage of the project an enormous improvement of the toughness properties of EB weld seams could be demonstrated based on optimisation of the welding process. Furthermore, it could be shown that by establishing the leakage before breakage criterion combined with regular inspections, the toughness requirements can be significantly reduced. Thus, the EB welding can be applied to offshore wind energy installations even if steels of higher yield strength (e.g. S460Q) are selected.

Fuzzy-Based Sediment Transport Simulation Using Contemporary Modeling Concepts and Measurement Methods as Validation

Das Projekt "Fuzzy-Based Sediment Transport Simulation Using Contemporary Modeling Concepts and Measurement Methods as Validation" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Wasser- und Umweltsystemmodellierung durchgeführt. An estimate of sediment transport rates in alluvial rivers is important in the context of erosion, sedimentation, flood control, long-term morphological assessment, etc. Extensive research during the last decades has produced a plethora of sediment transport models. Sediment transport is complex and often subject to semi-empirical or empirical treatment. Most of the sediment transport functions are based on simplified assumptions that the rate of sediment transport could be determined by one or two dominant factors, such as water discharge, average flow velocity, energy slope, and shear stress (Yang, 1996). In many practical situations prediction errors of these models are observed to be high.An alternative approach is to use data driven modelling, which is especially attractive for modelling processes about which adequate knowledge of the physics is limited, like in the case of sediment transport. Over the last decade fuzzy rule-based models have been introduced in engineering as a powerful alternative modelling tool. The fuzzy rule-based approach introduced by Zadeh (1965) is being widely utilized in various fields of engineering. It is a qualitative modelling scheme in which the system behaviour is described using a natural language (Sugeno & Yasukawa, 1993). This research focuses on the applicability of a data-driven fuzzy rule-based modelling approach in estimating sediment transport rates. It also aims at the comparison of the results of the fuzzy rule-based model with the results of other commonly utilized sediment transport functions.A number of variables play important roles in determining sediment transport capacity. These variables are: flow depth, particle fall velocity, particle diameter, flow velocity, energy or water surface slope, shear velocity, shear stress, fluid density, sediment density, stream power, unit stream power, and discharge. Additionally; size, shape, and unit weight of bed composition; morphology of bed forms and availability of sediment from source area affect sediment transport capacity. The most significant factors affecting sediment transport capacity will be identified and used for constructing a fuzzy model. The fuzzy model identification is usually carried out in two steps: (1) determining the number of fuzzy rules and their associated membership functions and (2) optimizing the fuzzy model. The fuzzy logic toolbox in MATLAB will be used for performing the fuzzy modelling.A general fuzzy system has the components of fuzzification, fuzzy rule base, fuzzy output engine, and defuzzification. Fuzzification converts each piece of input data to degrees of membership by a look-up in one or more several membership functions. Intuition, fuzzy clustering, neural networks, genetic algorithms, and inductive reasoning can be among many ways to assign membership values or functions to fuzzy variables...

Zuverlässigkeit und Haftung im Kontext von Climate Engineering: Eine integrierte Betrachtung (CELARIT)

Das Projekt "Zuverlässigkeit und Haftung im Kontext von Climate Engineering: Eine integrierte Betrachtung (CELARIT)" wird vom Umweltbundesamt gefördert und von Universität Bielefeld, Fakultät für Geschichtswissenschaft, Philosophie und Theologie, Abteilung Philosophie durchgeführt. In Anbetracht der potentiell katastrophalen Nebeneffekte von Climate Engineering (CE) wird generell ein passgenaues Haftungsregimes als Voraussetzung für einen international anerkannten und legitimen Einsatz für erforderlich gehalten. Diesbezüglich ergeben sich jedoch zwei grundsätzliche Fragen: Zum einen bedarf der Klärung, ob ein Haftungsregime als Mittel der Zuordnung und Verteilung von Risiken gewollt und realisierbar ist; zum anderen ist zu untersuchen, wie mit der Tatsache umzugehen ist, dass die Einschätzung der durch CE hervorgerufenen Klimaeffekte nur auf numerischen Klimamodellen, nicht aber auf empirischen Daten beruht. Obwohl das Thema der Haftung für CE-induzierte Schäden in der Literatur zunehmend Beachtung gefunden hat, wurde diesen Fragen bislang noch nicht systematisch Aufmerksamkeit geschenkt. Auch ist ungeklärt, wie Urteile über die Robustheit und Verlässlichkeit konkurrierender Modelle, die Auswirkungen eines CE-Einsatzes simulieren, getroffen werden können. Noch nicht beleuchtet worden ist schließlich, ob und wie die Entscheidung darüber, wie Beweise zu beurteilen sind, das Verhalten der Streitparteien (Staaten) beeinflusst, insbesondere im Hinblick auf die Frage, wann und ggf. wie CE eingesetzt wird. Angesichts dieser Forschungslücken kommt in vorliegendem Projekt, anders als in traditionellen Haftungsregimen, der Verlässlichkeit und Robustheit von Modellen zentrale Bedeutung zu. Vor diesem Hintergrund wird CELARIT (1) der Frage nachgehen, wie konkurrierende Modelle vor Gericht oder einem anderen zuständigen Gremium beurteilt, verglichen und bewertet werden können, und mit welchen Abstrichen erhöhte Robustheit und Verlässlichkeit einhergehen; (2) untersuchen, ob und ggf. nach welchen Kriterien ein Modell vor Gericht als zulässige Methode der Beweiserbringung herangezogen werden kann; und (3) erarbeiten, wie ein Schaden in einer Situation festgestellt werden kann, in der der kontrafaktische Zustand, welcher zur Ermittlung des Schadens herangezogen wird (eine Welt ohne CE oder sogar ohne Klimawandel), keiner Beobachtung zugänglich, sondern selbst Ergebnis eines numerischen Modells ist. Schließlich (4) wird das Problem in einem größeren Zusammenhang betrachtet. Es wird untersucht, wie Modelle trotz ihrer beschränkten Verlässlichkeit genutzt werden können, um mit CE zusammenhängende Maßnahmen zu steuern, und wie wissenschaftliche Politikberatung angemessen mit Unsicherheit und Nichtwissen umgehen kann. CELARIT bringt die Projektpartner von CEIBRAL (Klimamodellierer, Ökonomen, Juristen und Philosophen) erneut zusammen, geht jedoch insoweit einen großen Schritt über CEIBRAL hinaus, als eine methodische Neuorientierung in Richtung einer integrierten Untersuchung unternommen wird, und zwar von Anfang an disziplinübergreifend hinsichtlich sämtlicher Forschungsfragen.

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