The field of research called "Multiphysics" deals with the interdisciplinary investigation of systems with interacting physical effects. The main challenge herein is the combination of different complex solvers within a coupling scheme. An example for a multiphysical problem is the fluid-structure interaction (FSI) or aero-thermo-structural interaction, which takes also the influence of temperature into account.
Funding: DFG
Duration: 2023 - 2025
Team: D. Hahn, M. Haupt , S. Heimbs
Effective load reduction enables a significant mass reduction of the primary structures of aircraft wings and - directly as well as through secondary effects - also a reduction of the overall mass of the aircraft. This leads to a decrease in energy consumption and emissions. Previous research has shown that both active and passive concepts reach their limits in reducing dynamic loads over the entire flight envelope and for the relevant load cases. This collaborative project aims to demonstrate the feasibility of hybrid load reduction concepts that combine intelligent structural design exploiting structural and geometric non-linearities with unconventional actuation methods such as fluidic actuators and control surfaces operated in 'reverse mode'.
First, reference use cases and requirements for combining the individual load reduction concepts and methods are defined. Then, the passive load reduction concept realised by non-linear structures is applied to the use cases. Parameter studies are to prepare the basic understanding for the combined concepts. Hybrid concept combinations will be developed with the project partners. The most promising ones will be selected and optimised for medium and long range aircraft configurations over the entire flight envelope. Based on these results, a comprehensive comparison of different hybrid concepts for load reduction will be conducted. The long-term goal is to first evaluate the load reduction potential and then the integration and compatibility with other systems, as well as the climate-relevant impact on the entire aircraft. This project will identify novel approaches to achieve significant load reduction, aiming at the realisation of a 1 g wing. It will also provide important insights for flight control, overall aircraft design and scaled flight demonstrators within the SE2A cluster.
Funding: DFG
Duration: 2023 - 2025
Team: L. Kreuzeberg, M. Haupt , S. Heimbs
This project aims to explore the current technological blank spot of how the necessary dissipation of the waste heat of the fuel cell system via the aerodynamic surfaces can be achieved, especially in unconventional aircraft configurations such as the BWB configuration. The aim is not only to develop possible technological solutions but also to develop promising methodological approaches for modelling, analysis and optimisation.
This is done in close cooperation with the partner project "B4.1: Consistent Multilevel Model Coupling and Knowledge Representation in Multidisciplinary Analysis and Design", which deals with the general methodological approach for establishing a collaborative design environment, which is also to be developed and applied here.
For the concrete application, concepts for thermal management are being developed and the hitherto unknown sensitivities resulting from the coupling of the waste heat transport from the fuel cell via a cooling fluid and the heat conduction through the surface structure to the aerodynamic surface and from there to the aerodynamic flow around it are being analysed and investigated. The focus of the work here is on the thermal-mechanical structural design of possible surface panels, including integrity and adaptivity aspects.
In addition to the precise modelling of the individual disciplines involved and their consistent three-field coupling, an integral consideration of the entire system is carried out with the help of advanced multifidelity approaches and with the partners within the subprojects B4.1 and B4.2. This enables the optimisation with focus on the interactions of the surface with the external flow field, the weight-saving design of the internal structure with integrated cooling channels.
With the collaborative, multidisciplinary analysis capability involving the individual disciplines, the design spaces will be explored, characterised, researched and exploited.
Funding: BMWK (Luftfahrtförderungsprogramm 6.2)
Duration: 2024-2025
Team: Daniel Hahn, Matthias Haupt, S. Heimbs
The joint project "SKAiB: Skalierbare Brennstoffzellensysteme für elektrische Antriebe" is working on fuel cells for future commercial aircraft. The IFL is involved in the investigation and provision of models for low-drag heat exchangers in the outer skin. The waste heat from the fuel cells is supplied to the outside air via the thermal management system using coolant. If this waste heat can be released via heat exchangers integrated into the skin, conventional, drag inducing finned heat exchangers can be reduced. In addition, a heated boundary layer can reduce the frictional resistance of a turbulent flow. The IFL is developing models of varying accuracy for the panels of such skin heat exchangers. On the one hand, high-fidelity simulations of the coupled fluid and structural behaviour in differently sized cooling channels are created. On the other hand, faster low-fidelity models are created that can be used as part of the overall design.