Greece

Eco-design is an innovative design methodology that focuses on minimizing the environmental footprint of industries including aviation right from the conceptual and development stages. However rising industrial demand calls for a more comprehensive strategy wherein beyond environmental considerations competitiveness becomes a critical factor supported by additional pillars of sustainability such as economic viability circularity and social impact. By incorporating sustainability as a primary design driver at the initial design stages this study suggests a shift from eco-driven to sustainability-driven design approaches for aircraft components. This expanded strategy considers performance and safety goals environmental impact costs social factors and circular economy considerations. To provide the most sustainable design that balances all objectives these aspects are rigorously quantified and optimized during the design process. To efficiently prioritize different variables methods such as multi-criteria decision-making (MCDM) are employed and a sustainability index is developed in this framework to assess the overall sustainability of each design alternative. The most sustainable design configurations are then identified through an optimization process. A typical aircraft component namely a hat-stiffened panel is selected to demonstrate the proposed approach. The study highlights how effectively sustainability considerations can be integrated from the early stages of the design process by exploring diverse material combinations and geometric configurations. The findings indicate that the type of fuel used and the importance given to the sustainability pillars—which are ultimately determined by the particular requirements and goals of the user—have a significant impact on the sustainability outcome. When equal prioritization is given across the diverse dimensions of sustainability the most sustainable option appears to be the full thermoplastic component when kerosene is used. Conversely when hydrogen is considered the full aluminum component emerges as the most sustainable choice. This trend also holds when environmental impact is prioritized over the other aspects of sustainability. However when costs are prioritized the full thermoplastic component is the most sustainable option whether hydrogen or kerosene is used as the fuel in the use phase. This innovative approach enhances the overall sustainability of aircraft components emphasizing the importance and benefits of incorporating a broader range of sustainability factors at the conceptual and initial design phases.

Hydrogen as a zero-emission fuel produces only water when used in fuel cells making it a vital contributor to reducing greenhouse gas emissions across industries like transportation energy and manufacturing. Efficient hydrogen storage requires lightweight high-strength vessels capable of withstanding high pressures to ensure the safe and reliable delivery of clean energy for various applications. Type V composite pressure vessels (CPVs) have emerged as a preferred solution due to their superior properties thus this study aims to predict the performance of a Type V CPV by developing its numerical model and calculating numerical burst pressure (NBP). For the validation of the numerical model a Hydraulic Burst Pressure test is conducted to determine the experimental burst pressure (EBP). The comparative study between NBP and EBP shows that the numerical model provides an accurate prediction of the vessel’s performance under pressure including the identification of failure locations. These findings highlight the potential of the numerical model to streamline the development process reduce costs and accelerate the production of CPVs that are manufactured by prepreg hand layup process (PHLP) using carbon fiber/epoxy resin prepreg material.

Hydrogen is gaining attention due to its potential to address key challenges in the sectors of energy transportation and industry since it is a much cleaner energy source when compared to fossil fuels. The transportation of hydrogen from the point of its production to the point of use can be performed by road rail sea pipeline networks or a combination of the abovementioned. Being in the preliminary stage of hydrogen use the utilization of the already existing natural gas pipeline networks for hydrogen mixtures transportation has been suggested as an efficient means of expanding hydrogen infrastructure. Yet exploring this alternative major challenges such as the pre-existence of cracks in the pipelines and the effect of hydrogen embrittlement on the material of the pipelines exist. In this paper the macroscopic numerical modeling of pipeline segments with the use of the finite element method is performed. In more details the structural integrity of intact and damaged pipeline segments of different geometry and mechanical properties was estimated. The effect of the pipeline geometry and material has been investigated in terms of stress contours with and without the influence of hydrogen. The results suggest that the structural integrity of the pipeline segments is more compromised by pre-existing longitudinal cracks which might lead to an increase in the maximum value of equivalent Von Mises stress by up to four times depending on their length-tothickness ratio. This effect becomes more pronounced with the existence of hydrogen in the pipeline network.

This paper presents TwinP2G a software application for optimal planning of investments in power-to-gas (PtG) systems. TwinP2G provides simulation and optimization services for the techno-economic analysis of user-customized energy networks. The core of TwinP2G is based on power flow simulation; however it supports energy sector coupling including electricity green hydrogen natural gas and synthetic methane. The framework provides a user-friendly user interface (UI) suitable for various user roles including data scientists and energy experts using visualizations and metrics on the assessed investments. An identity and access management mechanism also serves the security and authorization needs of the framework. Finally TwinP2G revolutionizes the concept of data availability and data sharing by granting its users access to distributed energy datasets available in the EnerShare Data Space. These data are available to TwinP2G users for conducting their experiments and extracting useful insights on optimal PtG investments for the energy grid.