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The earth as we know it can only continue to exist if humanity finds a way to switch to a sustainable use of energy and resources. This work contributes to the research carried out to achieve this goal by improving the coating of adsorptive materials. These are used in heat transformation and drying processes that allow for efficient temperature and humidity control in buildings. A central component of these adsorptive coatings is the binder that acts as "glue" in the manufacturing of the coating. In this work the methods to evaluate binder performance regarding their thermal stability under the process conditions, their mechanical stability and their influence on the adsorptive properties of the coating were established. The coatings have to meet special requirements due to the thermal stresses and low pressure atmosphere they experience in these applications. A selection of silicone binders was then characterized with the established tests according to these requirements. Additionally a selection of inorganic binders was investigated because they allow for the use of high desorption temperatures and thus a high energy efficiency of the process. Out of these binders Silres® MP50E emerged as the most promising one due to very good adsorptive properties of the coating, its good temperature stability and ease of use. While some of the inorganic binders showed very good adsorptive properties and temperature stability the mechanical stability of all inorganic binders was not sufficient for their use in adsorption heat transformation technology. This is the first time that a broad selection of binders was evaluated with regards to adsorptive coatings and the results published in literature. With a suitable binder identified, the next step was to optimize the coating of the heat exchangers in order to work out how to manufacture the most efficient and powerful heat exchangers. Samples with different coating thicknesses were manufactured in small scale and full scale and their adsorption behavior was characterized. It could be shown for the first time that it is possible to increase energy efficiency by improving the mass ration of adsorber to coating and increase the delivered power at the same time. This was shown for small and full scale samples. It was shown that under the corresponding conditions the heat transfer from the coating layer to the adsorber metal substrate is the limiting step in the process. These results can now be used for the planning and construction of adsorbers. With knowledge of a suitable binder and how to coat efficient, powerful adsorbers, the coating process itself was improved to allow for industrial scale manufacturing. A central point here is the ability to control slurry rheology. Out of many rheology additives those that are suited for the application in adsorption heat transformation were identified and their influence on the slurry rheology thoroughly characterized. Additionally the process of slurry preparation could be simplified for several different adsorbents. Here it was shown that the supersonic deagglomeration step is not necessary to prepare a slurry. Extending the possible coating techniques and in addition to the dip coating process used so far, the spray coating of adsorptive coatings was established for the first time in literature. This process is widely used in the industry and allows for easier plugin into existing coating processes. For the coating of high resolution patterns a proof of concept of the screen printing process was carried out.
Enhancing cross-functional integration in new product development becomes increasingly important for industrial players to keep up with shorter product life cycles in technological innovation dynamics. Abundant research reflects the topic's significance, yet ambiguity in empirical results persists and industrial adoption of existing methods remains incremental. This thesis employs a qualitative approach to build a case study at the design-manufacturing interface of new product development of electrified cars. Cross-functional coopetition, as the joint occurrence of cooperation and competition, is adopted to generate an in-depth understanding of integration dynamics. Socio-organizational and contextual aspects are found to shape integration in a new product development context substantially. A model of interface dynamics is developed which provides for analysis and prediction of these aspects' impact on effective integration. A grounded theory approach to enhance integration is explored that introduces constraints as stimuli to consider manufacturability aspects in the design process. Constraint introduction is found to positively impact both cross-functional integration and creativity, with eight characteristics of constraint quality identified as moderating factors. A theoretical model is contributed which outlines cause-effect relationships of constraints' impact on antecedents of new product development success. It substantiates constraints' role in innovation contexts and encourages application for design-manufacturing integration as well as for other interfaces or purposes.
This doctoral research is located in the branch of sustainability sciences that has the realisation of sustainable development as its core subject of research. The most broadly accepted notion of sustainable development is that which evolves along the resolutions, declarations, and reports from international processes in the framework of the United Nations (UN). The consensual outputs from such processes feature global-generalised and context-free perspectives. However, implementation requires action at diverse and context-rich local levels as well. Moreover, while in such UN processes national states are the only contractual parties, it is increasingly recognised that other ("nonstate") actors are crucial to sustainability. The research presented here places the attention on bottom-up initiatives that are advancing innovative ways to tackle universal access to clean energy and to strengthen small-scale family farmers. This means, the focus is on bottom-up initiatives advancing local implementation of global sustainability targets, more precisely, targets that make part of the Sustainable Development Goals two and seven (SDG 2 and SDG7). The research asks how such bottom-up initiatives can contribute to the diffusion of sustainability innovations, thereby also contributing to social change.
Responsible consumption and production is one of the Sustainable Development Goals of the United Nations. To achieve this goal the currently high extraction rates of natural resources, that our economy is based on, needs a transformation of the consumption and production system considering technological as well as social change. One of the promising transition approaches is seen in collaborative consumption with its many facets of socio-cultural innovations and fast growing number of participants and businesses. With a decreasing production of goods, due to a utilisation of underutilised assets, these offers might support an absolute reduction of the global resource use. However, a positive environmental effect depends on the setting and the social practices of such sharing offers and is not sustainable or resource efficient generally. Also, resource efficient practices with a low diffusion potential that stick in a niche offer no leverage to achieve sustainable consumption patterns. Thus, this paper describes a mixed method approach to analyse the resource efficiency and diffusion potential of 20 sharing offers in the area of mobility, housing & travel and everyday objects in Germany. Results show that the overall positive environmental connotation of sharing offers cannot be confirmed. We identified five clusters of offers that are all treated to be differently when it comes to deploying the positive potential and avoid unnecessary societal effort to achieve the mentioned Sustainable Development Goal.
Nowadays, the main impetus to apply additive manufacturing (AM) of metals is the high geometric flexibility of the processes and its ability to produce pilot or small batch series. In contrast, resource and energy intensities are often not considered as constraints, even though the turnout of additive manufacturing is high, at least compared to chip removing processes.
The study at hand analyses the material characteristics and environmental impacts of a hose nozzle as an example of a commercial product of simple geometry. The production routes turning (conventional manufacturing) and laser beam melting (additive manufacturing) are compared to each other in terms of natural resource use, climate change potential and primary energy demand. It is found, that the product shows a lower demand for natural resources when produced via AM, but higher carbon emissions and energy demand when using a steel, that is mainly (80%) produced from high-alloyed steel scrap. However, different case studies during the sensitivity analyses showed that a number of factors highly influence the results: the steel source as well as the source of electricity play a major role in determining the environmental performance of the production routes. The authors also found that other production processes (here cold forging of tubes) might be an eco-friendly alternative to both routes, if feasible from an economic point of view.
In regard to the material characteristics, experimental testing revealed that the material advantages of AM produced hose nozzles (in particular higher yield strength) are reduced after a solution heat treatment is applied to the as-produced material, in order to increase corrosion resistance. However, products that do not require this production step might benefit from the higher yield strength, as a lower wall thickness could be realised.