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Framework for multi-fidelity simulations of flow interaction and noise of an open rotor
Get PDFFlow-induced noise from open rotor aircraft has received immense research interests as the flow interactions of the components of open rotors lead to significant non-linear features and the flow-induced noise is complicated. Numerical approaches for predicting open rotor flow interactions and the induced noise are in demand without compromising computational accuracy and reducing cost. In this paper, an existing multi-fidelity framework for propeller noise modelling is extended to open rotor configuration. A generic contra-rotating open rotor (CROR) configuration is developed to assess the capability of this multi-fidelity framework. The flow and noise of this configuration are modelled separately in hybrid manner. The flow solution is computed using two methods, which employ unsteady Reynolds average Navier-Stokes (URANS) equations and lattice-vortex method (VLM) at respectively higher- and lower-fidelity levels. Then, the acoustic solution is computed based on the flow solution using Gutin’s method. Results show that transonic features over the rotor blades and significant tip vortices in the wake characterise the CROR flow. Multi-rotor interactions are observed. The aerodynamic loadings are investigated in terms of their mean and fluctuating components. In addition, the far-field noise from the two rotors are compared. The present multi-fidelity framework will be used in future aircraft design which involves open rotor engines. This work is being administered as part of the Innovate UK, Aerospace Technology Institute (ATI) funded research project - ONEheart (Out of Cycle NExt generation highly efficient air transport).Innovate UKInnovate UK, Aerospace Technology Institute (ATI) in the UK, under the Out of Cycle NExt generation highly efficient air transport (ONEheart) project (Ref no.10003388).AIAA SCITECH 2025 Foru
Development and application of DNA hydrogels in biosensing: current status and future implications
Get PDFAs emerging biopolymer materials, DNA hydrogels quickly respond to external stimuli to specifically recognize DNA through base pairing and have become widely used in the field of biosensors. Unlike traditional biosensing strategies, biosensors based on DNA hydrogels are highly specific, programmable and degradable. In this work, based on the advantages and wide application of DNA hydrogels in the field of biosensors, the progress of DNA hydrogel biosensors is systematically summarized in terms of the types of DNA hydrogels, detection principles and biosensor device integration. First, the types of DNA hydrogels used in biosensors are briefly introduced. Next, we thoroughly demonstrate the detection principles of DNA hydrogel biosensors; the detection principles depend on the recognition elements, signal elements, and transduction types of the DNA hydrogel used in the biosensor. In particular, we demonstrate the great potential of integrated devices and techniques used in DNA hydrogel biosensors, such as microfluidics and portable devices. Finally, the challenges and future development of DNA hydrogels in biosensing are discussed. This work can be used as a reference for research on biosensing analysis using DNA hydrogels.The authors acknowledge the Youth Innovation Promotion Association CAS (2023415) and the Guizhou Provincial Science and Technology Projects (Qiankehe Platform Talents-GCC [2023] 046).Microchemical Journa
Nature-based stormwater management for aquifer recharge: exploring bioclogging-induced challenges
Get PDFUtilising excess urban stormwater to recharge groundwater can effectively mitigate the problems caused by the over-exploitation of subsurface environments while simultaneously making full use of valuable water resources. However, bioclogging can significantly reduce the efficiency of recharge projects in practical applications. This study is distinguished by its comprehensive consideration of unsaturated hydraulic conditions during stormwater recharge, which can influence microbial activities and the evolution of bioclogging, setting it apart from the predominant focus on saturated conditions in previous research. Microbial activity in the media became more vigorous under unsaturated conditions, and the cell volume decreased to 33–50 % of that under saturated conditions. Under unsaturated conditions, microbial EPS exhibited a curled morphology. At 60 % saturation, the contents of LB-EPS and polysaccharides increased by 141.23 and 187.47 μg/g sand, respectively, compared to saturated conditions. The reduction in saturation weakened microbial migration, promoted their deposition on the media surfaces, and reduced the non-uniformity of interlayer distribution. Simultaneously, unsaturated seepage conditions attenuated the effect of flow velocity (0.5–2 mL/min) changes on microbial migration and deposition. Bioclogging under unsaturated seepage conditions was governed by both EPS action and the EPS-bacterial interaction, with EPS secretion significantly influencing the degree of internal bioclogging development. This work contributes to a more comprehensive understanding of the bioclogging mechanisms under the unique hydrodynamic conditions of stormwater recharge, enabling more precise prevention and control of bioclogging during artificial stormwater recharge.This work was supported by the open fund from the Key Lab of Eco-restoration of Regional Contaminated Environment (Shenyang University), Ministry of Education (grant no.: KF-23–10), Special Basic Research Fund for Central Public Research Institutes of China (PM-zx951–202303–125), National Natural Science Foundation of China (42272284, 42277189), China Postdoctoral Science Foundation 2023M732396, Guangxi Key Research and Development Plan (No. Gui ke AB24010113).Environmental Technology & Innovatio
The role of cognitive capital in supply chain resilience: a focus on resilient interorganizational culture in supply chain networks
No full textThis thesis's central thread comprises three papers (i.e., Papers 1, 2, and 3). Paper 1
is a literature review consolidating the state of research on collaborative
interorganizational relationships in supply chain risks. Paper 2 is a case study that
explores the role of cognitive capital in supply chain resilience. Finally, Paper 3 is a
case study analyzing how resilient interorganizational culture functions in multi-tier
supply networks.
Firms increasingly engage in developing collaborative interorganizational relationships
(CIRs) to manage supply chain risks (SCRs) and improve supply chain resilience
(SCRES). While there is a wealth of fragmented studies on CIRs and SCRs, the
literature still lacks a synthetic theoretical articulation of how various aspects of CIRs
affect different SCRs. Employing a systematic literature review approach, Paper 1
grounds CIRs in the social capital theory to explain the role of structural, relational,
and cognitive capital residing in these relationships in various SCRs. The review
reveals that the three social capital dimensions positively and negatively affect
different SCRs (i.e., environmental, supply, manufacturing, demand, information,
financial, transportation). The findings suggest that the perceived SCRs can influence
structural and relational capital. Providing a future research agenda, the literature
review calls for researching how the underexplored cognitive capital aspect influences
SCRES.
Recognized as the most challenging dimension to operationally separate from other
social capital dimensions, cognitive capital has remained an elusive concept. Adopting
a buyer-supplier case study approach during a global disruption, Paper 2 unveils
different cognitive capital elements (e.g., shared goals, assumptions, values, kinesics
language, multilingualism, virtual negotiation, prior disruption experience, shared
process capabilities), and explains how they enable positively and episodically the four
SCRES temporal capabilities to prepare, respond, recover, and learn, under
contingencies of increased and decreased demands, and suppliers’ geographical
proximity.
Forming the core identity of interorganizational relationships, interorganizational
culture is a fundamental element of cognitive capital representing symbols and
meanings shared by groups or individuals from different organizations through
intersections of cultures and boundaries. Multiple research calls have highlighted the
lack of research on interorganizational culture in SCRES. Going beyond the
established dyadic view, Paper 3 enriches the existing literature by exploring the role
of interorganizational culture in SCRES in a multi-tier supply chain network. Using a
case study of a disrupted multi-tier supply chain network, Paper 3 identifies and
explains how aligned and misaligned interorganizational cultural elements (i.e., shared
goals, expectations, understanding, processes, values) impact the SCRES elements
of collaboration, flexibility, visibility, and velocity. Applying balance theory, the study
characterizes a resilient network-level interorganizational culture by highlighting
different supply chain network-level mechanisms (i.e., cultural alignment, propagation,
transitivity) influencing SCRES elements differently.PhD in Management and Leadershi
Low-power vibrothermography for detecting barely visible impact damage in CFRP laminates: a comparative imaging study
Get PDFThe data presented in this study are not publicly available due to ongoing research.This study explores the application of low-power vibrothermography (LVT) for detecting barely visible impact damage (BVID) in carbon fibre-reinforced polymer (CFRP) laminates. Composite specimens with varying impact energies (2.5–20 J) were excited using a single piezoelectric transducer with a nominal centre frequency of 28 kHz, operated at a fixed excitation frequency of 28 kHz. Thermal data were captured using an infrared camera. To enhance defect visibility and suppress background noise, the raw thermal sequences were processed using principal component analysis (PCA) and robust principal component analysis (RPCA). In LVT, RPCA and PCA provided comparable signal-to-noise ratios (SNR), with no consistent advantage for either method across all cases. In contrast, for pulsed thermography (PT) data, RPCA consistently resulted in higher SNR values, except for one sample. The LVT results were further validated by comparison with PT and phased array ultrasonic testing (PAUT) data to confirm the location and shape of detected damage. These findings demonstrate that LVT, when combined with PCA or RPCA, offers a reliable method for identifying BVID and can support safer, more efficient structural health monitoring of composite materials.This research was funded by Lembaga Pengelola Dana Pendidikan (LPDP) of the Ministry of Finance of Indonesia grant number 20210222226064. H.F. is grateful for the support provided by the Brazilian National Council for Scientific and Technological Development (CNPq) through grant number 312530/2023-4.Applied Science
Implications of military aircraft’s mission optimal performance on gas turbine engine life expectancy
No full textDevaiah, Nalianda - Associate SupervisorGas turbine engines have a crucial role in evaluating military aircraft performance.
Operating in a range of missions and environmental conditions, they are
subjected to an excessively demanding usage often reaching their operating
limits. The impact prediction on engine components degradation of this adverse
usage requires a multi-disciplinary approach to best capture its effects.
This master thesis investigates the implications of optimal mission performance
on the degradation of military gas turbine engines. The research focuses on the
degradation of first stage of the high-pressure turbine caused by the failure
mechanisms of creep, low cycle fatigue and high cycle fatigue, each acting
independently on the turbine blades.
By exploring the implications of mission performance on engine degradation, this
study provides valuable insights for optimizing mission execution strategies and
improving operational efficiency in military aviation.
Through a comprehensive analysis, several key findings have been identified. It
was observed that as the turbine entry temperature (TET) decreases, the
stresses on the turbine blade have a disproportionately greater effect on the
overall damage. This suggests that maintaining optimal TET levels is crucial for
mitigating engine degradation, as an increase of 0.005% in blade temperature
can lead to 40% more thrust, 100% more fuel consumption but can reduce life by
18% in Creep, 15% in LCF and 14% in HCF.
In addition, the study reveals that the use of afterburner though having similar
thermo-mechanical stresses upon the blades with the maximum dry setting, the
extensive usage in a mission can significantly impact the life consumption. A
mission with 40% less overall duration can present an up to 40% reduced life
expectancy.
Lastly, the investigation highlights the significant differences in life consumption
during several optimal climb paths. A time optimized profile is found to be the
most damage inflicting having 3 times less lifespan than noise and IR optimized
paths. A life expectancy of only 80 flight hours is predicted for the usage applied
on this profile resulting from the impact of low cycle fatigue contribution.
This research contributes to the field of military-related costs by shedding light on
the operational availability of gas turbine engines.MSc by Research in Aerospac
Additive manufacturing in edible product supply chain: a sustainable perspective
No full textAs the quest for healthier lifestyles intensifies, there is a growing demand for customized nutritional options, challenging the traditional food supply chain with its perishable goods and unpredictable demand patterns. This paper explores the potential of additive manufacturing, or 3D printing, as an innovative solution to these challenges. We present a conceptual framework to assess the impact of AM on the supply chain of edible products, including food and medicine, through the lens of sustainability—encompassing environmental, social, and economic perspectives. Our systematic literature review identifies five key strategies through which AM can enhance supply chain sustainability: distributed localized manufacturing, in-house production, delayed production, mass customization, and on-demand production. This research contributes valuable insights for industry practitioners and policymakers, guiding them toward exploiting AM's potential to revolutionize the sustainable supply chain management of edible products. Our findings highlight the transformative capabilities of AM and set the stage for future research directions in the nexus of additive manufacturing and sustainable supply chain practices.Hybrid Global Joint Conference on Industrial Engineering and Its Application Areas, GJCIE 2024Lecture Notes in Management and Industrial Engineerin
A study of control mechanisms in micro and nano system-enhanced polymer nanocomposites under mechanical and electrical stimuli: an experimental and computational investigation
Get PDFNanocomposite materials, particularly those reinforced with graphene
nanoplatelets (GNPs) and Barium Titanate (BaTiO₃), have been the focus of
extensive study within diverse industries aiming to enhance mechanical and
electrical properties. This thesis investigates the intricate relationship between
external mechanical and electrical stimuli and the effectiveness of these
reinforcing agents within nanocomposites, presenting significant findings and
novel contributions, while addressing an unexplored aspect within the field.
The research highlights a two-part exploration. The first part of the thesis details
the creation of GNP/BaTiO₃ polymer nanocomposite fibrils via mechanical
stimulation, specifically cold drawing, emphasising the compatibility of recycled
polypropylene (PP)/polyethylene terephthalate (PET) blends. The resulting fibrils,
exhibiting a significant aspect ratio disparity of 400:1, have demonstrated
substantially improved electrical, thermomechanical, and electromagnetic
properties. This in-situ mechanical stimulation (cold drawing) not only alters the
morphology but also enhances electrical conductivity, limits polymer chain
mobility, and reinforces the PP matrix, significantly improving its electrical,
thermomechanical, and electromagnetic interference shielding.
In the subsequent second part of the thesis, the study explored the integration of
graphene-based materials and BaTiO₃ within epoxy composites. Computational
modelling and statistical analysis have revealed the influence of these fillers on
DC conductivity, dielectric properties, and thermal behaviour. In addition, a
comprehensive examination of variations in filler thickness and volume
percentage that seemed to significantly impact material’s behaviour has been
investigated for the first time under electric fields. Specifically, the investigation
into BaTiO₃ nanoparticles and Si-BaTiO3 in epoxy under electric fields has
revealed the interplay between electrical stimuli, material properties, and
mechanical behaviour, highlighting ferroelectric and piezoelectric effects
observed in BaTiO₃ ceramics.i
This comprehensive study not only contributes novel findings but also
significantly fills a research gap within the field of nanocomposites by presenting
an in-depth examination of mechanical and electrical responsiveness, a study
that has not been previously undertaken in such a detailed and exhaustive
manner. The research conducted, sheds light on the potential for advanced
materials in diverse industrial applications and underscores the importance of
material selection, offering a pioneering step towards potential industrial
utilisation. Additionally, this research offers guidance for further computational
exploration, particularly in selecting GNP and BaTiO₃ materials to enhance the
electrical and thermal properties of the epoxy matrixEngineering and Physical Sciences Research Council (EPSRC)PhD in Manufacturin
Optimising vehicle performance with advanced active aerodynamic systems
Get PDFThis study investigates the performance potential of advanced active aerodynamic systems on high-performance vehicles. Static and active aerodynamic configurations, including asymmetrically actuated systems, are evaluated to identify performance gains and the mechanisms driving these improvements. Vehicle performance is optimised using a minimum lap time simulation framework, which utilises a transient vehicle dynamics model and CFD-derived aerodynamic data. Results indicate that configurations with greater aerodynamic adaptability enhance acceleration, braking, cornering, and straight-line performance, yielding notable lap time reductions compared to a static aerodynamic configuration. The asymmetrically controlled aerodynamic configuration achieves the highest lap time reduction of approximately 0.92 s (0.76%) due to its ability to modulate downforce both longitudinally and laterally. Optimal control strategies show that aerodynamic elements are actuated to balance vertical tyre load shifts resulting from load transfer, prioritising downforce on underloaded tyres in demanding scenarios like braking, cornering, and acceleration. Additionally, optimal design parameters for the brake, torque and roll stiffness distributions shift rearward as configurations provide greater control of aerodynamic loads on the rear axle. Overall, this research demonstrates the performance advantages of active aerodynamic systems and offers insights into the mechanisms underlying these enhancements, establishing a foundation for further innovations in the field.Vehicle System Dynamic
Unveiling host-guest interactions and stability of amine-functionalized silica sorbents for carbon capture
Get PDFDespite making significant progress in terms of capture kinetics and capacity, the thermochemical and cyclic instability of silica-based amine functionalized adsorbents present challenges for their practical implementation and economic viability. Accordingly, this work provides a critical review to analyse factors affecting thermal and cyclic stability of functional silica-based sorbents. The first section provides background information and context for the review. The second section focuses on the synthesis routes employed for silica-based amine functionalized adsorbents. The third section delves into the mechanism underlying the thermal and cyclic instability observed in these adsorbents. The fourth section explored the factors that influence the thermal and cyclic stability of silica-based amine functionalized adsorbents. The last section dissects host-guest interaction in silica-based amine functionalized adsorbents. The review concludes by underscoring the importance of further research and development into host-guest interaction studies in amine functionalized adsorbents to optimize performance and address the challenges associated with thermal and cyclic instability, thereby enhancing the practical feasibility of these adsorbents in carbon capture applications.Petroleum Technology Development Fund (PTDF) Nigeria doctoral study scholarship (Award Number: PTDF/ED/OSS/PHD/BOO/1710/20)Materials Today Sustainabilit