TY - GEN A1 - Seidlitz, Holger A1 - Hajhariri, Aliasghar A1 - Eberwein, Robert A1 - Perrone, Luca Pakj A1 - Cozzani, Valerio A1 - Otremba, Frank ED - Di Benedetto, Almerinda ED - Portarapillo, Maria T1 - Study the Impact of Spacer at Thermal Degradation Process of MLI-based Insulation in Fire Condition T2 - Proceedings of the 15th International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions N2 - To reduce carbon dioxide emissions, energy carries such as hydrogen consider to be a solution. Consumption of hydrogen as a fuel meets several restrictions such as its low volumetric energy density in gas phase. To tackle this problem, storage as well as transportation in liquid phase is recommended. To be able to handle this component in liquid phase, an efficient thermal insulation e.g., MLI insulation is required. Some studies have been revealed vulnerability of this type of insulation against high heat flux, for instance a fire accident. Some investigations have been depicted the importance of consideration of the MLI thermal degradation in terms of its reflective layer. However, limited number of studies have been focused on the thermal degradation of spacer material and its effect on the overall heat flux. In this study, through systematic experimental measurements, the effect of thermal loads on glass fleece, glass paper as well as polyester spacers are investigated. The results are reported in various temperature and heat flux profiles. Interpreting the temperature profiles revealed as the number of spacers in the medium increases, the peak temperature detectable by the temperature sensor on the measurement plate decreases. Moreover, the contribution of each individual spacer in all cases regarding the experimental temperature range is assessed to be around 8%. This value may increase to around 50% for glass paper and polyester spacers, and to around 25% for glass fleece spacers as the number of spacer layers increases up to six layers. To utilize the outcomes of the experiment later and integrate the results into numerical and CFD simulations, a model is proposed for the mentioned experimental temperature range up to 300°C to predict a heat flux attenuation factor. The model proposes a fitting factor that can reproduce the least square fitted line to the experimental data. KW - Multi-Layer Insulation (MLI) KW - Cryogenic KW - Liquid Hydrogen KW - Heat transfer Y1 - 2024 UR - https://zenodo.org/records/12621001 U6 - https://doi.org/10.5281/zenodo.12621001 SP - 744 EP - 755 CY - Napoli, Italy ER - TY - PAT A1 - Seidlitz, Holger A1 - Ambrosio, Marcello A1 - Müller, Michael A1 - Hansen, Torsten T1 - Sandwichlaminatstruktur, deren Verwendung und ein Verfahren zur Verwendung der Sandwichlaminatstruktur N2 - Sandwichlaminatstruktur mit einer ersten und einer zweiten Oberfläche, die einander gegenüberliegen, umfassend ein Kernelement, das eine erste Oberfläche und eine der ersten Oberfläche gegenüberliegende zweite Oberfläche aufweist, mindestens zwei Heizschichten, von denen mindestens eine Heizschicht auf der ersten und mindestens eine Heizschicht auf der zweiten Oberfläche des Kernelements angeordnet ist, und mindestens zwei Gewebelagen, von denen jeweils mindestens eine Gewebelage jeweils auf der dem Kernelement abgewandten Seite der mindestens zwei Heizschichten angeordnet ist, wobei das Material des Kernelements als Wabenvlies ausgebildet ist, welches Polyesterfasern, Polyamidfasern, Polyetherfasern und/oder deren Mischungen umfasst, wobei an den mindestens zwei Heizschichten Anschlüsse für eine Spannungsquelle angeordnet sind und die mindestens zwei Heizschichten als Leitfähigkeitssensoren zur Leckageüberwachung dienen. KW - Sandwichlaminatstruktur KW - Heizschicht KW - Leckageüberwachung Y1 - 2024 ER - TY - GEN A1 - Seidlitz, Holger T1 - Das Runde muss ins Eckige - mobile Wasserstoff-Kugelspeicher sollen Energieversorgung fächendeckend sichern T2 - CU reports N2 - Dem Wasserstoff-Transport widmen sich im TransHyDE-Projekt Mukran sechs Partnerinstitutionen aus Wissenschaft und Wirtschaft. Gemeinsam entwickeln sie neuartige sphärische Wasserstoffhochdruckspeicher mit einer lasttragenden Hülle aus carbonfaserverstärktem Kunststoff (CFK). Diese bieten einen „optimalen Kompromiss aus belastungs- und funktionsgerechter Geometrie“ und ermöglichen – eingebaut in standardisierte Containerquader – einen effizienten Transport mit hohem Nutzlastverhältnis. KW - Sphärische Wasserstoffhochdruckspeicher KW - Wasserstofftransport KW - Kugeltank KW - Wickelprozess Y1 - 2024 UR - https://digitalmagazin.b4bschwaben.de/de/profiles/610b21560ff9/editions/938f18855a9b7f4385ee/pages/page/13 SN - 2699-4534 VL - 01/2024 IS - 1 SP - 24 EP - 25 ER - TY - GEN A1 - Błędzki, Andrzej A1 - Seidlitz, Holger A1 - Köhler, Mathias A1 - Urbaniak, Magdalena A1 - Demski, Szymon A1 - Boczkowska, Anna T1 - Reusing and recycling of composite wind turbine blades. A review of current practices and prospects. Part 4.** Novel academic research T2 - Przemysł chemiczny N2 - A review, with 21 refs., of new resins for manufacturing, repair methods and recycling possibility stds. for established end-of-life management published in last 2 years. KW - Polymer composites KW - Wind turbine blades KW - High-performance wind turbines KW - Repair and recycling methods KW - End-of-life management KW - World’s largest wind turbines Y1 - 2025 U6 - https://doi.org/10.15199/62.2025.1.10 SN - 0033-2496 VL - 104 IS - 1 SP - 133 EP - 141 PB - Wydawnictwo SIGMA-NOT, sp. z.o.o. ER - TY - GEN A1 - Cieślik, Iwona A1 - Seidlitz, Holger A1 - Duchna, Monika A1 - Zasada, Dariusz A1 - Kwaśny, Mirosław A1 - Adamczyk-Cieślak, Bogusława T1 - Chemical method of doping Inconel 713C powder with rhenium for 3D printed manufacturing. Influence of rhenium dopants on the microstructure changes T2 - Archives of Civil and Mechanical Engineering N2 - A well-known method of doping powders in the industry is mechanical alloying synthesis. This method synthesizes metal powders by grinding them in high-energy mills, which prevents the achievement of well-dispersed particles throughout the volume and control of particle morphology, size, and agglomeration. In the present work, rhenium doping of IN 713C was carried out in a polyester network system based on organic acids and diols with specially selected catalysts and experimental parameters leading to the complexation of Rhenium ions. In addition, neutral reagents were used in this research, contributing to the greening of many key industries. The obtained IN 713C powder with rhenium showed high dispersion without agglomeration effect and reasonable flowability. Depending on the polymerization process parameters, the morphology of the rhenium particles on the surface of IN 713C can be modified. The IN 713C powder, with and without rhenium, was used in the SLM process to fabricate IN 713C alloy samples. The study examines the effect of rhenium doped IN 713C on the microstructure and hardness changes of the alloy produced by the 3D-printing methods. This type of chemical modification methods can effectively enhance the hardness and affects the elongation of dendrites in the structure of IN 713C alloys manufactured by the additive methods. KW - Rhenium KW - Chemical doping KW - Inconel 713C KW - Microstructure KW - 3D printing Y1 - 2025 U6 - https://doi.org/10.1007/s43452-025-01159-w SN - 2083-3318 VL - 25 IS - 2 PB - Springer Science and Business Media LLC ER - TY - GEN A1 - Popiela, Bartosz A1 - Günzel, Stephan A1 - Schukar, Marcus A1 - Mair, Georg W. A1 - Krebber, Katerina A1 - Seidlitz, Holger T1 - Impact of internal pressure control during manufacturing on residual stresses and safety performance of type 4 pressure vessels T2 - Composites Part C: Open Access N2 - Composite pressure vessels are commonly manufactured using the wet filament winding process, where various process parameters can influence the performance of the finished component. In this study two designs of wet filament wound 6.8-liter type 4 composite pressure vessels were manufactured. Both differ only by the internal pressure used during the filament winding, which primarily influences the residual stress state in the composite structure. An extensive experimental study was carried out, including 10 slow burst tests and strain measurements with fiber optic sensors. Significant differences can be observed in the performance of the two designs even though the used stacking sequence, materials and other manufacturing parameters are the same for both designs. A discussion of the differences in the behavior of both cylinder types is provided, including the strain distribution in slow burst tests and failure mechanism. KW - Residual stresses KW - Slow burst tests KW - Filament winding KW - Type 4 composite pressure vessels KW - Hydrogen Y1 - 2025 U6 - https://doi.org/10.1016/j.jcomc.2025.100581 SN - 2666-6820 VL - 17 PB - Elsevier BV ER - TY - JOUR A1 - Popiela, Bartosz A1 - Günzel, Stephan A1 - Sklorz, Christian A1 - Widjaja, Martinus Putra A1 - Mair, Georg W. A1 - Seidlitz, Holger T1 - Application of the incremental hole-drilling method for residual stress determination in type 4 pressure vessels JF - Materials Testing N2 - Hole-drilling method is a standardized technique for obtaining residual stresses in isotropic structures. Previous studies provide a foundation that enables the use of this method to investigate orthotropic structures, such as fiber-reinforced composites. In this study, the incremental hole-drilling method was applied to investigate residual stresses in filament wound type 4 composite pressure vessels. The investigated composite cylinders were manufactured with different internal pressure functions during the winding process, to achieve distinct residual stress states. Additionally, the influence of the initial loading under sustained internal pressure and increased temperature on the stress distribution was investigated. It was shown that the residual stress state can be influenced by varying the internal pressure in the winding process. After testing at sustained load and increased temperature, a stress redistribution was observed, which took place due to creep phenomena. Finally, a discussion of the challenges for the application of the hole-drilling method to composite pressure vessels is provided. KW - hole-drilling method KW - filament winding KW - type 4 composite pressure vessels KW - residual stresses KW - stress redistribution Y1 - 2025 U6 - https://doi.org/10.1515/mt-2024-0328 SN - 0025-5300 VL - 67 IS - 4 SP - 663 EP - 674 PB - Walter de Gruyter GmbH ER - TY - GEN A1 - Błędzki, Andrzej A1 - Seidlitz, Holger A1 - Köhler, Mathias A1 - Urbaniak, Magdalena A1 - Demski, Szymon A1 - Boczkowska, Anna T1 - Reusing and recycling of composite wind turbine blades. A review of current practices and prospects. Part 5**. New industrial projects. Wind energy in China T2 - Przemysł chemiczny N2 - A review, with 23 refs., of projects mainly from last 2 years currently commercialized by large consortia often in cooperation with academic teams. Many detail information about wind energy development and wind turbine blades recycling in China was delivered. KW - Polymer composites KW - Wind turbine blades KW - Currently project by large consortia KW - Wind energy in China KW - Comprehensive management methods Y1 - 2025 U6 - https://doi.org/10.15199/62.2025.1.11 SN - 0033-2496 VL - 104 IS - 1 SP - 142 EP - 152 PB - Wydawnictwo SIGMA-NOT, sp. z.o.o. ER - TY - JOUR A1 - Hartung, David A1 - Seidlitz, Holger A1 - Osiecki, Tomasz A1 - Sztorch, Bogna A1 - Przekop, Robert E. A1 - Kazimierczuk, Magdalena T1 - Flax fiber reinforced PET-G composites with improved interfacial adhesion JF - Polimery N2 - Recycled PET-G (rPET-G) composites reinforced with flax fiber were obtained. To improve interfacial adhesion, the fiber was treated by washing and finishing with bio-based epoxidized soybean oil and admixture acid. The effect of fiber surface treatment on its properties and those of the composites was evaluated by TGA, FT-IR and SEM, as well as by contact angle, flexural and tensile measurements. The results indicated delayed degradation of the treated flax fiber with a fiber mass loss of about 4 wt%. The flexural strength and modulus increased for the washed and finished flax fiber compared to the untreated one. While the tensile properties were influenced by structural effects resulting from the fiber treatment. These findings contribute to the development of more sustainable and high-performance natural fiber-reinforced thermoplastic composites. KW - natural fibers KW - composites KW - epoxidized soyabean oil KW - admergin acid Y1 - 2025 U6 - https://doi.org/10.14314/polimery.2025.2.4 SN - 2957-0263 VL - 70 IS - 2 SP - 113 EP - 123 PB - LUKASIEWICZ Research Network - Industrial Chemistry Research Institute CY - Warsaw ER - TY - GEN A1 - Seidlitz, Holger A1 - Gebhard, Johannes A1 - Stamp, Benno T1 - Nicht nur leicht, sondern auch recycelbar : Monomaterial ersetzt Multimaterialverbunde im Automobilinnenraum T2 - Kunststoffe N2 - Leichtbau spielt nicht nur bei Automobilen mit Verbrennungsmotoren, sondern auch bei Elektrofahrzeugen eine wichtige Rolle. Die dafür genutzten Materialverbunde lassen sich häufig jedoch nicht recyceln. Bei Mercedes-Benz setzt man deshalb seit Kurzem im Interieur auf Monomaterialsandwiche. Diese verbessern nicht nur die Recyclingfähigkeit, sondern bringen teilweise auch mehr Leistung. KW - Recycling KW - Monomaterial KW - Automobilinnenraum Y1 - 2025 UR - https://www.kunststoffe.de/a/fachartikel/nicht-nur-leicht-sondern-auch-recycelbar-6610346 UR - https://epaper.kunststoffe.de/read/24/24/2025-03-14/1 SN - 0023-5563 VL - 2025 IS - 03 SP - 18 EP - 21 PB - Carl Hanser Verlag CY - München ER - TY - GEN A1 - Seidlitz, Holger A1 - Gebhard, Johannes A1 - Stamp, Benno T1 - Not only lightweight, but also recyclable : mono-material replaces multi-material composites in car interiors T2 - Plastics insight N2 - Lightweight construction plays an important role not only in cars with combustion engines but also in electric vehicles. However, the composite materials used for this purpose are often not recyclable. Mercedes-Benz has therefore recently started developing mono-material sandwiches for the interior. These not only improve recyclability, but also increase performance in some cases. KW - Recycling KW - Mono-Material KW - Mercedes Benz KW - Lightweight Y1 - 2025 UR - https://en.kunststoffe.de/a/specialistarticle/not-only-lightweight-but-also-recyclable-6701555 SN - 2941-4202 VL - 2025 IS - 03 SP - 13 EP - 17 PB - Carl Hanser Verlag CY - München ER -