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RANS/LES and LBM/VLES aero-acoustic analysis of weapon bays at transonic Mach number
No full textNumerical aero-acoustic analysis was conducted on a weapon bay of a generic aircraft model using two conceptually different solvers, one based on the Navier-Stokes equations, the other based on the lattice-Boltzmann approach. The bay model was installed on a representative combat aircraft, incorporating doors and a store. The effect of angle of attack and store position on the aero-acoustic response within the weapon bay was analysed at a transonic Mach number of 0.90. It was found that both numerical approaches are capable of predicting, with good accuracy, the weapon bay’s acoustic spectrum (±10 dB) and store forces and moments (±10%),as compared to experimental data.AIAA Aviation Forum and Ascend 202
An optimization-driven design framework for inertance-integrated hydraulic shock absorbers: incorporating nonlinear and parasitic effects
Get PDFIntegrated spring-damper-inerter systems have been shown to outperform traditional damper-only absorbers in suppressing mechanical vibrations, driving interest in incorporating hydraulic stiffness, damping, and inertance components into automotive shock absorbers to enhance ride comfort. Extensive research has been conducted to identify the optimal absorber configuration from a vast design space. However, existing design approaches often neglect the nonlinear and parasitic effects (NPEs) inherent in hydraulic components and consider only limited topological layouts, thereby limiting the comprehensiveness and accuracy of the design space exploration. This oversight can result in discrepancies between simulated and real-world performance, potentially leading to suboptimal designs. To address this, a novel computer-aided engineering (CAE) framework is proposed for optimizing the configuration of inertance-integrated hydraulic shock absorbers. The framework follows a three-step process: (i) a graph-based method for enumerating all feasible hydraulic network layouts from a predefined catalog of components, (ii) an automated MATLAB subroutine for modeling these networks in Simscape, incorporating component models that explicitly account for NPEs, and (iii) a MATLAB-CarMaker co-simulation workflow for optimizing the hydraulic networks within a high-fidelity vehicle model. A case study involving a saloon car subjected to an ISO 8608 rough road input demonstrates the effectiveness of the framework. The optimized absorber design improves ride comfort by 17.6% when the NPE associated with hydraulic inertance realization is neglected and by 8.3% when it is considered, both while meeting dynamic tire load and suspension travel constraints. These results emphasize the importance of incorporating NPEs in the design process and validate the framework as an effective CAE tool for developing high-performance hydraulic absorbers for practical applications.Engineering with Computer
Methodology for exploring SOFC system layouts in a highly integrated hybrid propulsion system
Get PDFThis paper presents a methodology to compare different layouts of a solid oxide fuel cell (SOFC) system, focusing on component integration and constraints for low-emission aircraft propulsion. The SOFC system is a subsystem of an Integrated Power and Propulsion System (IPPS) fueled by hydrogen and tightly coupled with a micro gas turbine (mGT). The methodology presented here is applied to the case study of a mGT-SOFC and will later help to define the SOFC system layout for the 1MW+ IPPS of the FlyECO project.
Due to the low power density of current SOFCs designed for stationary applications, technology projections are used to explore a scenario of entry into service in 2050. Parametric analyses have been performed to consider possible future developments and performance opportunities on the basis of anticipated increases in SOFC power density, which so far could only be implemented on a laboratory scale.
Different SOFC system layouts are defined by assuming different aircraft operating conditions (take-off and cruise) as design point, due to the important impact of ambient pressure and temperature in-flight variation on the SOFC system, the related components and the overall performance. To maximize the synergy between SOFC and mGT, all layouts are based on a pressurized SOFC and include a heat exchanger for heat recovery and flow pre-heating.
The system performance exploration is carried out with the W-TEMP software, varying the hybridization factor of the mGT-SOFC system between 5% and 20%, and comparing its performance to a baseline H2-fueled mGT. The results obtained for this performance exploration report details on the coupling aspects between the micro gas turbine and the SOFC system and show clearly the advantages of mGT-SOFC integration in terms of net efficiency and production of water, which can be used in the combustion chamber of the mGT to limit the formation of NOx. In conclusion, a procedure to preliminary estimate the mass of the main components in each layout is also presented, to assess how different choices in the design of the mGT-SOFC can affect its weight.This project has received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No 101138488 and by the UK Research and Innovation (UKRI) funding guarantee under the project reference 10106893.ASME Turbo Expo 2025: Turbomachinery Technical Conference and Expositio
Corrigendum to “Deposition of alginate-oregano nanofibres on cotton gauze for potential antimicrobial applications” [Int. J. Biol. Macromol. Vol. 319 (2025), 1-16 Article 145, 372]
No full textOriginal article: Orisawayi AO, Lu H, Badruddin IJ, et al., (2025) Deposition of alginate-oregano nanofibres on cotton gauze for potential antimicrobial applications. International Journal of Biological Macromolecules, Volume 319, Part 1, August 2025, Article number 145372The authors regret that the < “Highlights” and “Graphical Abstract”, which were submitted during the manuscript submission process, were inadvertently omitted in the final published version of the article. These components were provided as part of the supplementary materials during submission and were intended to summarise and visually communicate the key findings of the study. For reference, the original highlights and graphical abstract are attached to this corrigendum. The omission does not affect the content, interpretation, or conclusions of the published manuscript. The authors would like to apologise for any inconvenience caused. Highlights i. Integration of nanofibres with a combination of alginate oregano essential oil (OEO) on cotton bandage.ii. Significant anti-bacterial properties against Methicillin-resistant Staphylococcus aureus (MRSA) and Listeria monocytogenes due to OEO integration.iii. Improved thermal stability of nanofibres, crucial for maintaining structural properties.iv. Utilise eco-friendly and cost-efficient materials as a potential alternative to conventional wound dressings.Graphical abstract[Figure presented]International Journal of Biological Macromolecule
Insights into crack prevention and property improvement for additively manufactured ultra-high-strength steel structures with complex geometries
No full textHybrid wire-arc directed energy deposition (WDED), in which complex features are deposited onto a forged base, offers a cost-effective solution for manufacturing geometrically complex ultra-high-strength steel components, particularly for aerospace applications. However, cracking at the base forging/build interface during post-build heat treatment limits its widespread application. This study investigates the underlying causes of interfacial cracking, highlighting microstructural inhomogeneity, elemental segregation and transformation stresses as likely key contributing factors. A modified three-step post-build heat treatment incorporating a normalisation step was developed to mitigate some of these issues. The optimised process successfully suppressed cracking by refining prior-austenite grains before the application of a conventional quenching step. This enhanced tensile performance beyond AMS6419K standards, supporting the industrial implementation of hybrid WDED in aerospace structures.This work is financially supported by the ‘Hybrid Direct Energy Deposition Sprint’ project (NO. 113345) funded by the Aerospace Technology Institute (ATI) and ‘Landing Gear Industrial Breakthroughs (I-Break)’ (10003486) funded by Innovate UK.The authors would also like to acknowledge facilities access and support from the Henry Royce Institute through EPSRC grants EP/R00661X/1, EP/S019367/1, EP/P025021/1, and EP/P025498/1.Additive Manufacturing Letter
Multi-task deep learning for lung nodule detection and segmentation in CT scans: a review
Get PDFThis article belongs to the Special Issue Signal and Image Processing Applications in Artificial Intelligence, 2nd EditionLung nodule detection and segmentation are essential tasks in computer-aided diagnosis (CAD) systems for early lung cancer screening. With the growing availability of CT data and deep learning models, researchers have explored various strategies to improve the performance of these tasks. This review focuses on Multi-Task Learning (MTL) approaches, which unify or cooperatively integrate detection and segmentation by leveraging shared representations. We first provide an overview of traditional and deep learning methods for each task individually, then examine how MTL has been adapted for medical image analysis, with a particular focus on lung CT studies. Key aspects such as network architectures and evaluation metrics are also discussed. The review highlights recent trends, identifies current challenges, and outlines promising directions toward more accurate, efficient, and clinically applicable CAD solutions. The review demonstrates that MTL frameworks significantly enhance efficiency and accuracy in lung nodule analysis by leveraging shared representations, while also identifying critical challenges such as task imbalance and computational demands that warrant further research for clinical adoption.Electronic
Stakeholder engagement in environmental innovation
Get PDFThis chapter explains why stakeholder engagement is even more critical for environmental innovation than for traditional innovation, arguing that learning how to successfully engage stakeholders in environmental innovation is one of the most critical levers in transforming our organizations and economy towards environmental, as well as social, sustainability. Five theoretical lenses that that are useful for thinking about stakeholder engagement in innovation are introduced: stakeholder theory, resource-based view, absorptive capacity, institutional logics and dynamic capabilities. The evidence from a systematic review of 88 peer-reviewed articles is synthesized into a framework for stakeholder engagement in environmental innovation, with each element of the framework illustrated with empirical evidence from eight case studies of environmental innovation partnerships. The framework sets out the engagement management, engagement learning and operational capabilities required to engage stakeholders in environmental innovation, as well as the outcomes and benefits of such engagement. Research directions are identified, and guidelines for practices are proposed.The Routledge Companion to Responsible Busines
Self-healing mechanism in polymer composite materials
Get PDFThe current self-healing mechanisms are still a long way from being fully
implemented, and most published studies have only shown successful damage
repair at the laboratory level. The complex nature of these mechanisms makes it
difficult to implement them in real-life situations where the component or structure
must continue to function. For complete healing, a molecular-level chemical
reaction is required with the aid of external stimuli such as heating, light, and
temperature change. Existing self-healing mechanisms are almost impossible to
implement in critical applications such as 3D-printed products due to the
requirements of external stimulations and reactions. The objective of this
research is to investigate the strain release behaviour during crack growth of
polymeric beams under elastic loads for self-healing. The mechanical behaviour
of polymer components has been studied for many years, and their basic features
are well understood. In this study, the elastic and plastic responses of 3D-printed
beams made of Acrylonitrile butadiene styrene (ABS), thermoplastic
polyurethane (TPU), and thermoplastic elastomers (TPE) were investigated
under different bending loads. Two types of 3D-printed beams were designed to
test their elastic and plastic responses under different bending loads. These
responses were used to develop an innovative self-healing mechanism based on
origami capsules that can be triggered by crack propagation due to strain release
in a structure. The origami capsules, made of TPU in the form of a cross with four
small beams either folded or elastically deformed, were embedded in a simple
ABS beam. When crack propagation occurred in the ABS beam, the strain was
released, causing the TPU capsule to unfold with the arms of the cross in the
direction of the crack path. This increased the crack resistance of the ABS beam,
which was validated in a delamination test of a double cantilever specimen under
quasi-static load conditions. The results showed the potential of the proposed
self-healing mechanism as a novel contribution to existing practises primarily
based on external healing agents. The self-healing mechanism of TPU and TPE
origami capsules has been demonstrated and reported for the first time. These
materials achieved a good balance of mechanical strength and self-healing
ability. A thicker beam structure tends to yield higher strain energy than do low
thickness values for the beam. Since the strain energy release is dependent on
how much cracking has propagated, so the higher strain release from the DCB
TPU star and roll contributes to the rate at which crack propagation extends.PhD in Manufacturin
On the application of trapped vortices in motorsport application for improved aerodynamic performance using passive and active flow controls
No full textNew regulations introduced by the Fédération Internationale de l’Automobile (FIA) for the 2026 Formula 1 season mark the first instance of active flow control methods being endorsed in Formula 1 competition. While active methods have demonstrated significant success in airfoil development, their broader application to grounded vehicle aerodynamics remains unexplored. This research investigates the effectiveness of trapped vortex cavity (TVC) technology in both active and passive flow controls, applied to a NACA0012 airfoil and an inverted three-element airfoil from a Formula 1 model. The investigation is conducted using numerical methods to evaluate the aerodynamic performance and potential of TVC in this paper. In the single-airfoil case, a circular cavity is placed along the trailing edge (TE) on the suction surface; for the three-element airfoils, the cavity is positioned on each airfoil to determine the optimum location. The results show that the presence of a cavity, particularly with active flow control, significantly improves the lift-to-drag ratio (CL/CD) for both the single airfoil and the three-element airfoils. A maximum enhancement of 1160% was recorded for the single airfoil, while the three-element airfoils saw an improvement of 313% compared to their original configurations. However, when the TVC was placed in positions other than the TE of the mid-airfoil, a performance reduction was observed, even with active blowing applied. The passive flow control approach, which requires no additional energy input, yielded a modest improvement of 3.52% for the NACA0012 airfoil. However, passive control underperformed due to unstable vortex interactions with each airfoil element for the inverted three-element airfoil case. Even with optimal placement and geometrical modifications, the maximum CL/CD ratio for passive control was only 96% of the original CL/CD of the unmodified three-element airfoils, suggesting that passive flow control is less effective here compared to active flow control
Dataset " Protective performance of building cladding against fragmentation impact"
No full textThe dataset supports a journal article investigating the fragment penetration performance of low carbon construction materials subject to improvised explosive devices. The dataset contains the experimental data collected during gas gun testing and results discussed in the article.British Arm