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Tracking the grounding line migration at Getz Ice Shelf using Sentinel-1 A/B
Get PDFThe grounding line (GL) defines the boundary of grounded ice of marine ice sheets in Greenland and Antarctica. The speed and extent of GL retreat indicate the ice sheet stability, making it essential to track and quantify their migration. Grounding lines move in response to changes in the ice sheet geometry, and they also exhibit periodic displacements due to tidal ice shelf flexure. This tidally induced motion enables the accurate and spatially dense mapping of GLs using Synthetic Aperture Radar (SAR) satellites via Differential Interferometric SAR (DInSAR).
We have developed a statistical method to analyze DInSAR-derived GLs, allowing us to identify regions of high spatial variation and extract migration patterns from our generated time series. We present its application to the GLs of Getz Ice Shelf in Antarctic
Enhancing Aeolus Data Quality: From Processor Evolution to Reprocessing Campaigns in Aeolus DISC Phase F
Get PDFCoupled Mode Flutter Analysis of Turbomachinery Blades Using a Frequency Domain Coupling Scheme for the p-k Method
No full textAerodynamic coupling of mode shapes becomes a concern for turbomachinery blades with a low mass ratio of structure-to-air.
Applying the p-k method allows to investigate the aeroelastic stability equation but comes with a high computational effort when aerodynamic forces have to be computed at various sampling points in advance.
The work presents a new approach in an attempt to reduce the effort by coupling the frequency domain CFD solver with the eigenvalue solution
MEmilio v2.2.0 - A high performance Modular EpideMIcs simuLatIOn software
No full textMEmilio implements various models for infectious disease dynamics, from simple compartmental (ODE) models through Integro-Differential equation-based (IDE) models (sometimes also denoted "age of infection models") to agent- or individual-based models (ABMs). Its modular design allows the combination of different models with different mobility patterns. Through efficient implementation and parallelization, MEmilio brings cutting edge and compute intensive epidemiological models to a large scale, enabling a precise and high-resolution spatiotemporal infectious disease dynamics
Konzeptionierung und Auslegung eines Mechanical Ground Support Equipments für CubeSats unter Berücksichtigung von Responsive Space Bedingungen
Get PDFDie Bachelorarbeit Konzeptionierung und Auslegung eines Mechanical Ground Support Equipments für CubeSats unter Berücksichtigung von Responsive Space Bedingungen umfasst die gesamte Entwicklungsphase eines Produktes. Diese erstreckt sich von der Bedarfsermittlung und Konzeption bis hin zur Erstellung eines finalen CAD-Modells. Der Prozess ist strukturell angelehnt an die VDI 2221 unter Verwendung klassischer Entwicklungsmethodiken. Eine zusammenfassende Auswertung und das Resümee schließend diese Arbeit ab
Computational Fluid Dynamics Simulation for a Parametric Preswirl Rotor-Stator System
No full textThe secondary air system (SAS) has a significant impact on the performance and lifetime of the
aero engine. More than 20 % of the core flow is passed through the SAS, so its optimization is one
essential step to increase the efficiency of the entire engine. The system is a network of a great number
of elements with different complexity levels. While for some elements, like pipes or orifices, general
characteristics suffice to represent the physical behavior, for other elements or even sub-domains these
models are very sensitive and may get inaccurate with changes in design or operating conditions. This
justifies the use of 3D simulations for discrete domains that can give a more detailed picture of the
flow field. The results of these simulations can be made available for use in the 1D network model.
Vice versa the network model can provide boundary conditions for the 3D simulations, like mass flow
and temperature at the domain boundaries. An interesting domain to investigate with a 3D CFD
simulation is the stator-rotor cavity of the first high-pressure turbine stage. On the one hand cooling
air is provided for the rotor disk and blades and on the other hand inflow of hot gas into the inner
wheel space is prevented. The cavity is fed by a preswirled flow through nozzles and additionally by
a cross flow through the leakage between the stator and rotor walls from a lower radius. This leads to
a formation of a complex vortex structure in the cavity, which requires detailed 3D CFD simulations
to show all flow phenomenons accurately.
The geometrical design of those cavities differs considerably between different engines. A major
research interest lies in varying the considered geometry and in studying the effects of individually
changed geometric parameters. This allows to gain experience, which parameters are the essential
factors for optimization of the SAS. For this purpose, a parametric geometrical model that enables
the independent variation of single parameters is presented.
The steady-state RANS simulation is performed with the CFD solver TRACE, which is being
developed by DLR. The numerical setup is discussed and an overview of the flow behavior in the
cavity is given. An evaluation of the numerical methods is part of the research
Computertomographie - Potential und Anwendungsgebiete am DLR
No full textIn diesem Vortrag werden Anwendungsgebiete der Computertomographie anhand von Praxisbeispielen gezeigt. Potentiale und künftige Werkzeuge und Möglichkeiten werden auch diskutiert
FoxBench - Benchmark Array File Formats
No full textFor effective data exchange and transfer, choosing the proper file format is crucial. Different
domains have specific standards for file formats. While CSV files are commonly used, they lack
reusability. Data files are well-suited for computing clusters as they enable efficient data processing
and storage across multiple interconnected systems. Data analytics pipelines can be time-consuming
due to handling large volumes of data. Timely data access is crucial for efficient processing and
analysis. Earth system science (ESS) data commonly manifests as dense or sparse n-dimensional
data. Dense n-dimensional data is conventionally stored in arrays, while sparse n-dimensional data
is typically housed in data frames. In the realm of ESS, an array of file formats is leveraged for the
storage of dense n-dimensional data, including NetCDF4, TileDB, and Zarr. The paper at hand aims
to evaluate data file formats for retrieving multidimensional data, specifically focusing on tools within
the ESS domain. The insights from this exploration will be applicable to other data analytics projects
AEM Electrolysis Deep-Dive
No full textVortrag über den Ursprung von Überspannungen in der AEM-Elektrolyse