Model-Based Design of High Energy All-Solid-State Li Batteries with Hybrid Electrolytes

As the aircraft industry becomes more committed to sustainable aviation, hybrid-electric propulsion systems containing batteries with higher gravimetric energy density attract increasing attention to reduce fuel consumption. Future aircrafts could benefit from next-generation chemistries like oxide-based all-solid-state Li-battery (ASSB) technologies. However, producing and evaluating a wide range of design parameters for maximising the gravimetric energy density of ASSB experimentally is both time- and resource-intensive. Physics-based modelling promises to identify optimal designs for battery cells with respect to high gravimetric energy density more time and cost-efficient. In this regard, we applied a pseudo-two-dimensional model for the model-based evaluation of Li-ASSB with various hybrid electrolytes containing oxide and polymer electrolytes. This way we elucidate which electrolyte performs well with present technology and which has the potential to become an attractive alternative in the future. After identifying design variables to improve ASSB with the help of sensitivity analysis, a genetic algorithm is used to predict the optimal design parameters to achieve higher gravimetric energy density. The conducted study reveals that ASSB based on 12.7 vol% of garnet Li$_{6.4}$La$_{3}$Zr$_{1.4}$Ta$_{0.6}$O$_{12}$ (LLZTO) is the best option based on present manufacturing constraints. Hybrid electrolytes based on 10 wt% of Li$_{1.3}$Al$_{0.3}$Ti$_{1.7}$(PO$_{4}$) $_{3}$3 (LATP) could be promising for future aircrafts with further improvements in ASSB manufacturing process

Structural Batteries for Aeronautic Applications—State of the Art, Research Gaps and Technology Development Needs

Radical innovations for all aircraft systems and subsystems are needed for realizing future carbon-neutral aircraft, with hybrid-electric aircraft due to be delivered after 2035, initially in the regional aircraft segment of the industry. Electrical energy storage is one key element here, demanding safe, energy-dense, lightweight technologies. Combining load-bearing with energy storage capabilities to create multifunctional structural batteries is a promising way to minimize the detrimental impact of battery weight on the aircraft. However, despite the various concepts developed in recent years, their viability has been demonstrated mostly at the material or coupon level, leaving many open questions concerning their applicability to structural elements of a relevant size for implementation into the airframe. This review aims at providing an overview of recent approaches for structural batteries, assessing their multifunctional performance, and identifying gaps in technology development toward their introduction for commercial aeronautic applications. The main areas where substantial progress needs to be achieved are materials, for better energy storage capabilities; structural integration and aircraft design, for optimizing the mechanical-electrical performance and lifetime; aeronautically compatible manufacturing techniques; and the testing and monitoring of multifunctional structures. Finally, structural batteries will introduce novel aspects to the certification framework

Structural Batteries for Aeronautic Applications—State of the Art, Research Gaps and Technology Development Needs

Radical innovations for all aircraft systems and subsystems are needed for realizing future carbon-neutral aircraft, with hybrid-electric aircraft due to be delivered after 2035, initially in the regional aircraft segment of the industry. Electrical energy storage is one key element here, demanding safe, energy-dense, lightweight technologies. Combining load-bearing with energy storage capabilities to create multifunctional structural batteries is a promising way to minimize the detrimental impact of battery weight on the aircraft. However, despite the various concepts developed in recent years, their viability has been demonstrated mostly at the material or coupon level, leaving many open questions concerning their applicability to structural elements of a relevant size for implementation into the airframe. This review aims at providing an overview of recent approaches for structural batteries, assessing their multifunctional performance, and identifying gaps in technology development toward their introduction for commercial aeronautic applications. The main areas where substantial progress needs to be achieved are materials, for better energy storage capabilities; structural integration and aircraft design, for optimizing the mechanical-electrical performance and lifetime; aeronautically compatible manufacturing techniques; and the testing and monitoring of multifunctional structures. Finally, structural batteries will introduce novel aspects to the certification framework

Aerodynamic Interaction of High-Speed Trains with Infrastructure Components

Recent projects of alp-crossing tunnels (Brenner Tunnel 57 km, Koralm 33 km, Semmering 27 km) lead to a special focus of investigations in aerodynamic interaction and design concepts for the tunnel equipment. Train passing of High- Speed Rails cause pressure or suction which lead to dynamic loading on sidelong infrastructure components. In tunnels the pressure loads are up to 10 times higher compared to loads on noise barrier walls situated along the open track. The waves are reflected at the tunnel portals and claim the fatigue strength of different tunnel installations. This paper presents exemplary the impact of dynamic interaction and influence on fatigue strength on internal tunnel installations for different tunnel configurations. The pressure loads were taken by using Computational Fluid Dynamics (CFD) analysis calibrated on experimental validations at the Tunnel Simulation Facility Göttingen (TSG) in model scale experiments (1:25). A generic model of the Austrian Railjet manufactured with 3D printing was run at speeds up to 230 km/h. The pressure predicted by CFD compare remarkably well with the measurements. Various configurations of the tunnel cross section and cavities of cross passing of a single track tunnel were tested. The pressure during and after train passage were evaluated, and used for the time-dependent numerical analysis to calculate strain and deformation by the transient loading on tunnel installations. For a typical configuration of installation the technical life span was evaluated and compared with the cumulative damage method after Palmgren- Miner. The Life Cycle Analysis LCA showed that the geometry of shallow cavities of the tunnel walls has only minor influence on the theoretical service life of structural components. However, the numerous wave reflections occurring at the door position after the train has passed has a substantial impact on the service life

Assessment of the pressure load in cavities in a single-track tunnel by model-scale experiments and CFD simulation

In the Alps, several very long single-track, twin-tube tunnels either have been opened recently (Gotthard Base Tunnel, CH) or are under construction (Koralm Tunnel, AT; Brenner Base Tunnel, AT-IT; Semmering Base Tunnel, AT). Pressurized cross-passage tubes spaced every 325 to 500 meters interconnect the main tunnel tubes and are sealed with air-tight doors which must sustain high pressure loads. The impact of the cavity between the main tube and the cross passage door on the pressure load was studied in model-scale (1:25) experiments at the Tunnel Simulation Facility Göttingen (TSG) and with Computational Fluid Dynamics (CFD). In the narrow, single-track model tunnel, a shallow cavity was installed at the location where both the train head with strong gradients in its attached pressure field and the train entry wave reflected from the opposite tunnel exit arrive at the same time. Thus, the maximum possible pressure drop is generating at this position. Three different shapes were tested, a narrow and a wide with rectangular base and a wide with trapezoidal base, all enlarging the cross-section area up to 25%. A generic model of the Austrian Railjet manufactured with 3D printing was run at speeds up to 230 km/h. CFD simulations using unsteady RANS with sliding mesh approach were set up according to the experiments. The pressure development during the Railjet passage through the plain tunnel predicted by CFD compare remarkably well with measurements. For the cross tunnel cavities, the TSG test conditions were simulated. The potential of the various configurations to mitigate the pressure load in the cavity and the impact of the cavities on the tunnel pressure during and after train passage were evaluated. The change of the extremal pressure in comparison to the plain tunnel is rather small (10-15%). However, the wide cavities show a tendency of increasing the pressure load while the narrow cavity gives rather neutral results, even showing some potential to reduce pressure waves after the train has left the tunnel

Sexl Physik 8: für die 7. und 8. Klasse der allgemein bildenden höheren Schulen (2. Teil)

Dieser Band behandelt die Physik des 20. Jahrhunderts (Relativitätstheorie, Quantenmechanik, Kern- und Teilchenphysik, Kosmologie) im philosophisch-historischen Kontext. Wie in jedem Band des Lehrgangs sind übersichtliche Zusammenfassungen, Test- und weiterführende Fragen sowie Rechenbeispiele enthalten

Sexl Physik 7: für die 7. und 8. Klasse der allgemein bildenden höheren Schulen (1. Teil)

Die Schwerpunkte dieses Bandes sind die Erarbeitung der Themen Optik, Atombau und Elektrodynamik über einen historisch-philosophischen Zugang. Wie in jedem Band des Lehrgangs sind übersichtliche Zusammenfassungen, Test- und weiterführende Fragen sowie Rechenbeispiele enthalten

Analysis of pressure loads on installations in high-speed tunnels- with model scale experiments and numerical simulations

Trains passing through railway tunnels cause pressure and suction waves which affect the vehicle, tunnel equipment, and passenger comfort. In the Alps, several very long single-track, twin-tube tunnels either have been opened recently or are under construction. Pressurized cross passage tubes spaced every 333 to 500 meters interconnect the main tunnel tubes and are sealed with air-tight doors which must sustain high pressure loads. The impact of various configurations of the shallow cavity between the main tube and the cross passage and the pressure loads generated on installations in different configurations of high-speed tunnels are analysed by using Computational Fluid Dynamics (CFD) analysis and experimental validations at the Tunnel Simulation Facility Göttingen (TSG) in model scale experiments (1:25). The effects on internal tunnel installations (e.g., emergency exit doors) were investigated in connection with their structural dynamics using FEA. The life span was evaluated and compared with the cumulative damage method after Palmgren-Miner

Auswirkung aerodynamischer Zugsbelastungen verschiedener Tunnelkonfigurationen auf Tunnelnotausgangstüren

Zugsdurchfahrten in Eisenbahntunneln verursachen aerodynamische Belastungen durch Druck/Sogwellen, welche Fahrzeug, Tunnelausrüstung und den Fahrkomfort beeinträchtigen können. Im Rahmen eines kürzlich abgeschlossenen Forschungsprojekts wurde die aerodynamische Auswirkung bei Zugsdurchfahrten von Hochgeschwindigkeitszügen mittels strömungsmechanischen Berechnungen untersucht und mit der in ihrer Art weltweit einzigartigen und innovativen Tunnelsimulationsanlage (TSG) des Deutschen Zentrums für Luft- und Raumfahrt (DLR) in Göttingen versuchstechnisch bestätigt. Der Beitrag umfasst die Untersuchung von Tunnelausrüstungsgegenständen am Beispiel einer Notausgangstür mit unterschiedlichen aerodynamischen Belastungen bei Zugsdurchfahrten. Mittels numerischen Analysen im Zeitbereich wurden unterschiedliche Türkonfigurationen (Variation der Eigenfrequenzen) mit den errechneten bzw. gemessenen Drucksignaturen belastet, und auf dynamische Erhöhung und Zusatzschwingungen untersucht. Anschließend wurde die Schädigungssumme mittels linearer Schadensakkummulation nach der Hypothese von Palmgren-Miner auf Ermüdung bewertet und die theoretische Lebensdauer ermittelt. Es konnte unter den getroffenen Annahmen exemplarisch gezeigt werden, welche Parameter positive Effekte auf die theoretische Lebensdauer von Ausrüstungsbauteilen aufgrund der Belastungsänderung haben. Die Forschungsarbeiten wurden im Rahmen des VIF 2014 Projekts OPTUNAMIK durchgeführt und von der ÖBB-Infrastruktur AG sowie der österreichischen Forschungsförderungsgesellschaft finanziell unterstützt