Modellierung und Charakterisierung für eine präzise Werkstoffbeschreibung
Das Forschungsvorhaben strebt an, durch eine umfassende Digitalisierung sowie anwendungsspezifische Charakterisierung und Modellierung der Werkstoffe eine realitätsnahe Beschreibung von Druckbehältern zu entwickeln. Ziel ist es, das Verhalten des Gesamtsystems während der Herstellung und im gesamten Produktlebenszyklus präzise abzubilden und so die Auslegung inline-überwachter Druckbehälter zu optimieren.
Lightweight pressure vessels are a key enabler for the use ofCO2-neutral, hydrogen-based drives in transportation. While battery storage will continue to dominate the passenger car sector in the foreseeable future, hydrogen is now the preferred solution as an alternative to conventional fuels for heavy vehicles such as trucks, buses, trains and marine applications. However, the hydrogen must be stored at high pressures (350-700 barü) or low temperatures. Due to the lightweight construction requirements, this can only be attractively implemented for mobile applications by using carbon fiber reinforced plastics (CFRP) as a material.
© IKVTraditionally, these thick-walled structures are manufactured from thermoset systems using the wet winding process. However, the significantly higher material utilisation should be emphasised, which has a positive effect on theCO2 savings potential. The laminate structure of the fiber composite winding is determined to a large extent by the limits of the fiber sliver placement options. A homogenisation of the local stress in the laminate and thus optimum material utilisation has not yet been achieved, which leads to overdimensioning and thus increased material usage. Furthermore, the effective properties of the material, ageing and loads are of a stochastic nature, which currently also leads to significant overdimensioning. However, this over-dimensioning can be reduced by developing and using inline-capable process monitoring to detect strength-reducing process deviations.
The technological objective of the research project is to achieve a realistic description of the container materials and the overall system during manufacture and the product life cycle by means of end-to-end digitalization and application-specific characterization and modelling. The interactions within the machine-process-material-morphology-material property relationship will be analysed experimentally and simulatively, modelled using suitable methods and made usable for optimisations in the simulation in the form of a digital twin of the manufactured pressure vessels. Building up this understanding and mapping it in virtual methods is a central goal in order to significantly increase the degree of material utilisation and thus ensureCO2 savings through resource efficiency.
Furthermore, alternative materials such as pre-impregnated fiber tapes, so-called towpregs, are to be improved and used, which promises a high material savings potential. Particularly with regard to the materials used, a pronounced dependence of the mechanical properties on hydrostatic pressure, temperature and physical stress, such as the influence of media, can be seen, which also has an effect on the damage behaviour. To this end, the research project is developing a testing system that enables materials to be tested under cyclic, dynamic triaxial loads using hydrogen as the pressure medium.
Project data and funding
The research project (03LB3099A) is funded by the Federal Ministry of Economics and Climate Protection (BMWK) as part of the program “CO2 savings through resource efficiency and substitution” from the announcement of the Technology Transfer Program Lightweight Construction (TTP LB). The consortium project comprises a total of ten partners from research and industry along the entire value chain of pressure vessel production and is coordinated primarily by IKV Aachen.
Project duration: 01.07.2023 – 30.06.2026
Funding:
