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A laboratory-scale solid oxide fuel cell (SOFC) system using liquefied natural gas (LNG) as a fuel is designed to be used as an energy converter on seagoing vessels (MultiSchIBZ project). The presented system design phase is supported by thermodynamic system simulation. As heat integration plays a crucial role with regard to fuel recirculation and endothermic pre-reforming, the heat exchanger and pre-reforming component models need to exhibit a high degree of accuracy throughout the entire operating range. Compact additively manufactured tube-bundle and plate-fin heat exchangers are designed to achieve high heat exchange efficiencies at low pressure losses. Their heat transfer correlations are derived from experimental component tests under operating conditions. A simulation study utilizing these heat exchanger characteristics is carried out for four configuration variants of pre-reforming and heat integration. Their system behaviour is analyzed with regard to the degree of pre-reforming and the outlet temperature of the fuel processing module. The combination of allothermal pre-reforming with additively manufactured plate-fin heat exchangers exhibits the best heat integration performance at nominal full load and yields a partial load capability to up to 60% electrical load at net electrical efficiencies of 58 to 60% (LHV).

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Neben Geschmack und Schmelzverhalten ist der Glanz ein wichtiges Qualita ¨tskriterium von eingetafelten Schokoladenprodukten. Glanzunterschiede der Produkte ko ¨nnen auf verschiedene Ursachen im Produktionsprozess zuru ¨ckgefu ¨hrt werden. Der Ku ¨hlprozess stellt dabei einen signifikanten Einfluss dar. Die durch Scheren und Unterku ¨hlen vorkristallisierte Schokolade wird weiter abgeku ¨hlt, kristallisiert und fest aus dem Ku ¨hlprozess heraustransportiert. Das Ku ¨hlen der Schokolade im Paternoster-Ku ¨hlschrank ist weitestgehend unerforscht und wird daher in dieser Arbeit hinsichtlich des sich ergebenen Stro ¨mungsprofils und des resultierenden Temperaturprofils numerisch untersucht.

In addition to taste and melting behavior, the gloss is an important quality criterion of chocolate products. Differences considering the gloss on products can be attributed to different causes in the production process. The chocolate which has been precrystallized by shearing and supercooling is further cooled, crystallized, and transported as a solid chocolate out of the cooling process. The cooling of the chocolate is largely unexplored in a paternoster refrigerator. Therefore, the resulting flow profile and temperature profile are numerically studied in this work.