Preliminary design trades for the liquid hydrogen storage system of a short-range aircraft are presented. Two promising insulation methods, namely rigid foam and multilayer insulation, are identified as main design drivers. In addition, the maximal pressure and the shape of the hydrogen storage tank influence the aircraft performance and the insulation efficiency. In this study, the hydrogen storage tanks are integrated in wing pods. The main effects driven by the design parameters are addressed using conceptual and preliminary methods: models are carried out for the storage mass, additional drag, propeller efficiency loss and the dynamical thermodynamic behavior of the liquid hydrogen storage. These effects are coupled making an integrated design method necessary. For the sizing of the liquid hydrogen storage, a multidisciplinary workflow is set up including the aircraft sensitivities on the design mission block fuel. The trade-off study reveals the opposing trend between insulation efficiency and aircraft performance. For the insulation architecture based on rigid foam, the penalties implied by the storage tank on aircraft level and the penalties due to vented hydrogen can be balanced and result in minimal block fuel for the design mission. The application of multilayer insulation avoids venting during the design mission, but has an increased penalty on the aircraft performance compared to rigid foam insulation. Besides the criterion of minimal block fuel, the dormancy time is compared, indicating the thermal efficiency. Applying multilayer insulation, the dormancy time can be increased significantly calling for a discussion of operational requirements for hydrogen-powered aircraft.

The aircraft design process is a complex task that requires the collaboration of disciplinary experts from various fields. In practice, this complexity requires a large investment in setting up communication interfaces for the exchange of disciplinary data, and serious misinterpretations are not uncommon. To increase the efficiency and robustness of data exchange, a common language is essential. As such, the Common Parametric Aircraft Configuration Schema (CPACS) serves as a central data model, which currently includes detailed parametrizations of aircraft geometry and analysis results from traditional disciplines (e.g., aerodynamics, structure, etc.). However, with the recent interest in alternative propulsion and complex on-board system architectures, CPACS is proving to be too limited to meet the needs of the various disciplinary system experts. The particular challenge here is to enable different views on the same systems, i.e., a functional/logical as well as a geometric/physical representation, without violating the principle of unambiguous data. Therefore, this paper proposes an extension of CPACS which introduces an explicit system definition covering both representations. Its potential is demonstrated by two use cases from disciplinary experts in the field of on-board system design at the Hamburg University of Technology (TUHH), based on data provided by aircraft design experts. Through validation against the experts’ needs, the proposed system definition proves to bridge the gap between preliminary aircraft design and on-board system design, enabling a holistic, robust and efficient aircraft design process.

The design of novel aircraft concepts powered by electric propulsion systems is a highly multidisciplinary task that requires expert knowledge to be included in the early design phase. Such expertise is typically provided by engineering routines that are not directly linked to the overall aircraft design. This paper presents a digital framework to employ heterogeneous methods at component level to size a complete electrical powertrain within the aircraft design process. A standardized interface and an automated execution workflow are developed to enable consistent data exchange between disciplines, integration of the powertrain architecture into the data model, and synthesis of component results within the overall aircraft design process. The framework is applied for the sizing of the powertrain of a plug-in hybrid electric aircraft. By supporting the integration of expert knowledge at component level in the aircraft design process, this paper facilitates technology assessment at the early design stage.

Liquid Hydrogen (LH2) as an energy carrier for passenger aircraft has the potential to combine low climate impact and high lifecycle energy efficiency. Due to its significantly different physical properties compared to kerosene, the integration of LH2 fuel storage and distribution systems interacts with the general configuration of the aircraft. In order to assess promising configuration combinations quantitatively, an aircraft design and assessment framework is further developed. These additions are aimed at capturing the interdependencies originating from the fuel system integration choices at the aircraft level and quantifying the effect of trim drag. The framework is applied to a selection of LH2 mid-to-long-range aircraft designs. A comparison of the mass breakdown, aerodynamics breakdown and performance indicators such as specific energy consumption is carried out for the framework-generated aircraft models. A trim drag induced block fuel penalty is quantified for the aircraft selection as well as a mitigation strategy based on operational constraints.

In this paper, we present an approach to automate the evaluation and improvement of geometric requirements during preliminary aircraft design, specifically focusing on the complex integration of subsystems like fuel systems. Utilizing the Codex (COllaborative DEsign and eXploration) platform and its submodule codex-geometry, we use Semantic Web Technologies (SWTs) to create a domain-neutral, integrated data representation. The system checks for compliance with geometric constraints in order to reduce manual work in the design. Building on previous work for requirement evaluation, this current research expands the system’s capabilities to suggest improved component placements when geometric inconsistencies are detected. The capabilities of this approach are demonstrated in an example use case placing fuel system components. Furthermore, we explore the use case of design space allocation impacted by an uncontained engine rotor failure.