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Degradation and fatigue life methods for ceramic matrix composite and nickel superalloy materials in gas turbine combustor liner
Get PDFThis paper investigates the durability of Ceramic Matrix Composite (CMC) and Nickel Superalloy materials in gas turbine combustor liners across different flight conditions. Thermo-mechanical and physical properties of CMCs are assessed and compared with selected superalloys (i.e., Inconel 625, Hastelloy X, SiC/SiC, Al2O3/B4C, and Al2O3/SiO2) using Finite Element Analysis (FEA). An integrated methodology employing Computational Fluid Dynamics (CFD) and FEA is introduced to analyze thermal stresses and fatigue life, establishing a direct connection between combustion dynamics and structural responses. The study addresses a research gap by thoroughly evaluating CMC materials in gas turbine combustor liners, offering valuable insights for material selection and design strategies in aerospace engineering. The findings enhance understanding of CMC behavior, showcasing their reliability and durability for gas turbine components and their usage for advancements in aerospace applications.This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under grant agreement No 886840International Conference on Flexible Automation and Intelligent Manufacturing (FAIM 2024)Flexible Automation and Intelligent Manufacturing: Manufacturing Innovation and Preparedness for the Changing World Orde
A modular multifidelity approach for multiphysics oleo-pneumatic shock absorber simulations
No full textA numerical framework is developed and tested to simulate the internal dynamics of oleo-pneumatic shock absorbers. A modular approach is devised to address the multiphysics nature of the problem, starting with three dimensional scale resolving turbulence simulations and two dimensional axisymmetric multiphase URANS simulations. These simulations capture the main dominant aspects of energy dissipation through turbulence, and the multiphase mixing which can affect the working fluid properties. Internal flow simulations are run on a representative shock absorber geometry based on dimensions provided in the validation study together with sizing guidelines from the literature. A lower fidelity two-equation dynamic system solver is used to scan the design space and test the sensitivity towards various design parameters, in addition to identifying parameter combinations that would be of interest to investigate using higher fidelity methods.This research was funded by Innovate UK grant number 10002411Proceedings of the Cambridge Unsteady Flow Symposium 2024Proceedings of the Cambridge Unsteady Flow Symposium 202
Experimental investigations on solid and metal-cored creep-resistant wires deposited under GMA and PTA-based wire arc additive manufacturing (WAAM)
Get PDFWire arc additive manufacturing (WAAM), also known as Arc-DED, possesses great potential for efficient production using various materials and wire types. This study utilized gas metal arc (GMA) and plasma transferred arc (PTA) variants of WAAM to deposit 2.25Cr-1Mo steel employing a metal-cored wire (MCW) and a solid wire counterpart having the same chemical composition for the comparative study. Initially, bead-on-plate trials were conducted with both WAAM processes and different shielding gas combinations in GMA-WAAM using the cored wire. The heat input versus deposition ratio was analysed to assess the heat input and the effects of shielding gases in GMA-WAAM. Arc behaviour was monitored with a process camera, and bead morphologies and dilutions were compared. Furthermore, test walls were deposited under the two WAAM processes and the shielding gas conditions, employing the cored and solid wire. Detailed microstructural study was conducted through optical microscopy, and hardness tests were performed to determine the mechanical properties. Energy dispersive X-ray spectroscopy (EDS) was used to examine the elemental composition and potential segregation in walls deposited with cored and solid wires. Results indicated a lower heat input when using cored wire and variable heat input due to shielding gases. A bainitic/martensitic microstructure was observed in test walls deposited with cored and solid wires with comparable microstructural features. The PTA process produced higher hardness than GMA, and solid wire exhibited slightly higher hardness than cored wire. Selection of shielding gas also influenced the hardness. Finally, the EDS maps and elemental study revealed comparable results for both wires. The results show good performance and outcome for cored wire.The International Journal of Advanced Manufacturing Technolog
Data "Raw thermograms for Multi-parameter optimisation for thermal diffusivity estimation using through transmission thermography"
No full textReduction in ochratoxin a occurrence in coffee: from good practices to biocontrol agents
Get PDFOchratoxin A (OTA) is a mycotoxin mainly produced by Aspergillus section Circumdati and section Nigri across the coffee chain. OTA is nephrotoxic and is a threat to human health. This review summarizes current knowledge on how to reduce OTA concentration in coffee from farm to cup. After a brief introduction to the OTA occurrence in coffee, current good management practices are introduced. The core of this review focuses on biocontrol and microbial decontamination by lactic acid bacteria, yeasts and fungi, and their associated enzymes currently reported in the literature. Special attention is given to publications closest to in vivo applications of biocontrol agents and microbial OTA adsorption or degradation agents. Finally, this review provides an opinion on which future techniques to promote within the coffee supply chain.Cranfield University, Centre de Coopération Internationale en Recherche Agronomique pour le DéveloppementJournal of Fung
Recent advances in mechanical analysis and design of dynamic power cables for floating offshore wind turbines
Get PDFThis review paper presents a comprehensive analysis of the mechanical design and analysis of dynamic power cables for marine renewable energy applications, focusing on research from the last two decades. The review covers key aspects such as mechanical properties, failure mechanisms, fatigue analysis, experimental studies, local cable analysis, and global load analysis. The study aims to provide a concise summary of the state-of-the-art, identifying recent advancements and research gaps in the field. The methodology involves a systematic review of relevant literature, including journal articles, conference papers, and industry reports. The findings are synthesised to provide insights into the current understanding of power cable design and analysis, as well as to highlight areas requiring further research and development. The review is intended to serve as a valuable resource for researchers, engineers, and stakeholders in the marine renewable energy sector, contributing to the development of more reliable and cost-effective dynamic power cable solutions.Ocean Engineerin
Chlorine-induced stress corrosion cracking of single crystal superalloys at 550 °C
Get PDFThis study has investigated the effect of NaCl and different gaseous environments on the stress corrosion cracking susceptibility of CMSX-4 at 550 °C. The presence of SOx leads to the rapid dissociation of NaCl into Na2SO4 and the release Cl2 and HCl, which then trigger an active oxidation mechanism and stress corrosion cracking. The incubation time for crack initiation at 690 MPa and in the presence of a sulphur containing environment is 10 min. A working hypothesis is that stress corrosion cracking occurs due to the hydrogen released at the oxide/alloy interface when metal chlorides are formed; however, this hypothesis needs to be further explored.Rolls RoyceHigh Temperature Corrosion of Material
Understanding the interests of academics from diverse disciplines to identify the prospective focus for a UK-based transdisciplinary network involving farm-to-fork stakeholders on antimicrobial resistance in agrifood systems: an online survey
Get PDFAntimicrobial resistance (AMR) evolution and onward transmission of resistance genes is impacted by interrelated biological and social drivers, with evidence and impacts observed across human, animal and environmental One Health domains. Systems-based research examining how food production impacts on AMR in complex agrifood systems is lacking, with little written on management approaches in the UK that might prevent and respond to this challenge. One approach is the creation of a transdisciplinary network to enhance capacity, capability and collaboration between agrifood-focused disciplines and stakeholders. This co-creation platform for network-wide systems-based activities would reduce inefficiencies in AMR-related activities around agrifood, providing a cross-cutting, cohesive community to deliver transformational guidance on relevant, practical agrifood solutions that add value by reducing AMR, antimicrobial usage and associated costs, and decreasing resultant environmental contamination by prioritising challenges, sharing knowledge and best practice, and co-creating practical solutions with key stakeholders. An online survey determined prospective network focus, structure and priorities, with responses analysed using mixed methods. Survey results suggested respondents have interests in synthesising data using systems-approaches and using certain disciplines such as ‘social sciences’ within network activities. There were disconnects in how and whom to work with on this, with generalised use of ‘social science/scientists’ but lack of disciplinary understanding (e.g., anthropology, sociology) suggesting disciplinary differences awareness-training is useful. A similar generalisation is seen for mathematics/statistics. There are strong interests in working with food system practitioners (e.g., farmers/vets), providing opportunities for farm/field visits/knowledge exchange, and human health, reflecting the need for farm-to-fork understanding of impacts. There were notable mentions of policy/governance, emphasising translational research desires to create meaningful change. Disciplines/fields did not always align with identified interests e.g., systems and implementation science, suggesting the utility of network activity around introducing these disciplines e.g., methodology-focused rather than subject-focused conferences exploring lateral thinking about subjects. We suggest starting by developing understanding of the most important research questions by working with stakeholders, then working back to how we would achieve desirable project outcomes and who else is needed for this.The authors thankfully acknowledge their individual funders for their support for this work, including the Food Standards Agency, Quadram researchers, the BBSRC, and the Academy of Medical Sciences (AMS).One Healt
Computational investigation of the aerodynamic performance of an optimised alternative fuselage shape
Get PDFPurpose – The purpose of this study is to re-evaluation fuselage design when the main wing’s has the ability to fulfill stability requirements without the need for a tailplane. The aerodynamic requirements of the fuselage usually involve a trade-off between reducing drag and providing enough length for positioning the empennage to ensure stability. However, if the main wing can fulfill the stability requirements without the need for a tailplane, then the fuselage design requirements can be re-evaluated. The optimisation of the fuselage can then include reducing drag and also providing a component of lift amongst other potential new requirements.
Design/methodology/approach – A careful investigation of parameterisation and trade-off optimisation methods to create such fuselage shapes was performed. The A320 Neo aircraft is optimised using a parameterised 3D fuselage model constructed with a modified PARSEC method and the SHERPA optimisation strategy, which was validated through three case studies. The geometry adjustments in relation to the specific flow phenomena are considered for the three optimal designs to investigate the influencing factors that should be considered for further optimisation.
Findings – The top three aerodynamic designs show a distinctive characteristic in the low aspect ratio thick wing-like aftbody that has pressure drag penalties, and the aftbody camber increased surface area notably improved the fuselage’s lift characteristics.
Originality/value – This work contributes to the development of a novel set of design requirements for a fuselage, free from the constraints imposed by stability requirements. By gaining insights into the flow phenomena that influence geometric designs when a lift requirement is introduced to the fuselage, we can understand how the fuselage configuration was optimised. This research lays the groundwork for identifying innovative design criteria that could extend into the integration of propulsion of the aftbody.Aircraft Engineering and Aerospace Technolog
Developing a stackable programme based on the advanced air mobility systems MSc course
Get PDFFor the purpose of open access, the author has applied a Creative Commons Attribution (CC BY) license to any Author Accepted Manuscript version arising.This study proposes the development of content and materials for a stackable programme that aligns with the existing Cranfield University Advanced Air Mobility Systems (AAMS) MSc Course and integrates with ongoing Future Flight Challenge (FFC) projects, emerging research and development (R&D) capacities, and the growing demand for skilled professionals in the sector. The programme is structured into four phases: enhancement of taught modules through technology-enhanced teaching (TET), enrichment of project-based learning, bolstering of student experience and career development, and a stackable approach adaptable to various educational levels. This approach was evaluated using courses from the 2022/23 and 2023/24 academic years.This research is funded by the Future flight: closing the skills gaps project Stackable Programme on Advanced Air Mobility, grant number 10069102.2nd IFAC Workshop on Aerospace Control Education - WACE 2024IFAC-PapersOnLin