In the project AKIRA concepts for the connection of thermal protection systems to cryogenic fuel tanks of reusable spacecraft are developed and tested. The challenge lies in the effective, weight-optimized insulation of the cryogenic fuel tank while simultaneously minimizing heat flows in the TPS mountings to prevent local overheating of components.
DLR (CC BY-NC-ND 3.0).
For the DLR flight experiment REFEX, the department is responsible for the design and construction of the metallic structure of the missile, the folding wings and the fibre composite fairings.
Within the VLM project thermally stable stabilization fins were developed. The supporting structure consists of CFRP/sandwich, the leading edge of GFRP and the fuselage connection of aluminium. The joints are completely glued. Compared to a metal structure, it was possible to save 25% mass at double the stiffness without incurring costs.
Within the framework of the Collaborative Research Centre TRR40, basic investigations on transpiration cooling are carried out in cooperation with the Institute for Thermodynamics of Aerospace at the University of Stuttgart. For the future design of transpiration-cooled systems, numerical and analytical models will be developed and validated by means of detailed experiments.
The 3-stage small carrier VLM and the 2-stage ballistic version VS-50 are developed in German-Brazilian cooperation. The department is responsible for the fairing structure, the tail structure with stabilising fins and the mechanical separation system. At DLR, the project is managed by the Mobile Rocket Base (MORABA).
As part of the HGF camp initiative DLR@UniST, the ZURAM® ablative thermal protection material was developed. The characterisation in plasma wind tunnels of the Institute for Space Systems of the University of Stuttgart and the Institute for Aerodynamics and Flow Technology of the DLR in Cologne has shown a performance on the level of comparable materials such as PICA (NASA) or ASTERM (Arianegroup). Thanks to its 3D reinforcement, ZURAM® is highly resistant to shear forces.
In addition to the temperature resistance of the materials, the minimisation of thermal expansion and expansion management play a central role in the mostly hybrid design concepts of spacecraft. This is particularly true in the field of space propulsion. In the field of satellites, the department is working on innovative approaches for the cost-effective development and construction of highly integrated commercial satellite systems. Technologically, the focus is on new manufacturing processes for satellite structures and propulsion.
In addition to basic research, the work is predominantly project-oriented and should lead to proven and operational structures. This system-oriented approach leads to the integration of different areas during the development process. Within the department, all necessary disciplines are covered from the preliminary draft to the qualification test. In addition to commercial FEM and CAD software, special simulation tools are available in the area of design and calculation. Research work on actively cooled structural elements is a focal point.
During the production of the corresponding structural components, the competences of other departments of the institute are integrated in addition to our own production facilities. This means that almost all material classes and corresponding manufacturing processes are available for structural design. To qualify the systems, our own testing facilities and various non-destructive testing methods are available. A realistic testing of the structures is aimed at in-flight tests. This usually takes place within joint projects at national and European level and in cooperation with other research institutions.