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Assessment of non-elliptic lift distributions on span-extended wing design
Get PDFIn the pursuit of reducing the environmental impact of aviation, novel aircraft concepts
and technologies are receiving increased attention from researchers and manufacturers.
Amongst the solutions expected to improve aerodynamic efficiency, aircraft
with high aspect ratio wings are being regarded as a promising solution, despite the
numerous hindrances derived from such a configuration. Furthermore, the current
socio-economic prospect has exacerbated the need to address the multi-disciplinary
nature of the conceptual design process, in which traditional methods are becoming
less reliable for the modelling of the envisioned novel configurations and technologies.
To address some of these challenges, an elegant analytical approach promising
improvements in the aero-structural efficiency and flight dynamic characteristics of
wings has gained the interest of researchers around the world. This design approach
proposes to remove the fixed-span constraint and instead prescribe structural requirements.
This yields a set of non-elliptic lift distributions with theoretically improved
aero-structural efficiency and lateral-directional flight dynamic characteristics. However,
conclusions on the actual benefits and practical implications of the application
of this theory remain unsettled. This thesis investigates some of the research questions
posed by such an approach applied to the conceptual design of high aspect ratio
wings. To do so, it provides a multidisciplinary physics-based design environment
that integrates in-house developed and existing computational models within a setbased
design approach. This allows for the analysis of feasible solutions with regard
to overall performance improvement whilst shedding light on the relevant trade-offs.
The proposed design and analysis approach yields span-extended configurations
for which aerodynamic efficiency is improved through span extension and the consequent
growth in wing structural weight is reduced as a result of the applied non-elliptic
spanloads. The presentation of alternative figures of merit to comparatively assess the
performance of the designs provides further insight than the use of other traditional
metrics such as the lift-to-drag ratio. This yields several span-extended configurations
without penalties in performance, following the methodology and metrics employed
in the proposed design and analysis process. Furthermore, the semi-analytical approach
to proverse yaw enables to identify the unconventional behaviour of induced drag during aileron deflection on wings with the selected non-elliptic spanloads. Additionally,
it highlights that attainment of these solutions are highly dependent on flight
condition, aileron sizing and location within a given spanload, and the magnitude of
deflection. Overall, this thesis contributes to a further insight on the aero-structural
trade-offs and proverse yaw characteristics derived from the use of such a design
approach. This can facilitate the identification of the determining contributors and
compromises to be made at early stages of the design, amplifying the designer’s control
over the design and decision-making processes, while delaying critical decisions
and enhancing the optimisation process with more informed drivers.PhD in Aerospac
Modeling and simulation of cold hearth continuous casting of titanium alloys
Get PDFIn the present study, an alternative sustainable method of manufacturing Ti6Al4V alloys from industrial scraps/swarfs is discussed. CFD modeling and simulation of cold hearth continuous casting process is done using FLOW-3D TruVOF and FAVOR techniques. A high-performance computing is utilised to optimise the computing resources to simulate the hydrodynamic and thermal behaviour of the liquid metal. Simulations with different superheating temperatures is conducted to understand the flow properties and solidification. These findings provide valuable insights into understanding of flow properties and thermal distribution for reliable molten metal delivery contributing to efficient recycling and sustainable manufacturing processes.The project was funded by an EPSRC Programme Grant SAM (EP/W01906X/1)Light Metals 2025. TMS 2025 Annual Meeting & Exhibitio
Risk assessment for digital transformation projects in construction Enterprises: an enhanced FMEA model
Get PDFThe digital transformation of the construction industry is crucial for advancing global digital economies, but it involves significant risks that require a standardized and robust assessment methodology. This paper presents an enhanced Failure Mode and Effect Analysis (FMEA) model that integrates the Multiple Attribute Border Approximation Area Comparison (MABAC) method with Grey Relational Analysis (GRA). Unlike previous approaches, this integration aligns grey relational changes with border approximation vector components, capturing both positive and negative correlations between modes. This enhances the prioritization process by distinguishing failure modes that may amplify or mitigate each other’s impact, leading to more precise risk assessments and mitigation strategies. The model also employs interval numbers instead of crisp numbers to reduce information loss from decision-making ambiguities caused by heterogeneous expert evaluations. Applied in a real-life case study, the improved model effectively accommodates biases and hesitations in expert decision-making, enhancing the accuracy and reliability of risk assessments in digital transformation projects. The findings highlight the model’s potential as a comprehensive and reliable framework for identifying, prioritizing, and mitigating risks in the digital transformation of the construction industry.Expert Systems with Application
Comparative life-cycle assessment of novel steel section design with wire arc additive manufacturing
Get PDFAdditive manufacturing, particularly Wire Arc Additive Manufacturing (WAAM), is emerging as a promising technology in the construction sector due to its potential to reduce environmental impacts. Life-Cycle Assessment (LCA) is a crucial methodology for evaluating the environmental footprint of products and processes that can be carried out from raw material extraction to the end of production, commonly referred to as “cradle-to-gate” analysis. This study focuses on the environmental impact of 3D-printed steel elements using WAAM technology for construction applications. Specifically, the conventional production of Circular Hollow Section (CHS) steel components was compared with the innovative production of Tubular Sandwich Section (TSS) steel components using WAAM. The analysis provides a comparison of the carbon footprint associated to both production methods, highlighting in detail the emission factors associated with each step of the WAAM production. The results highlighted that WAAM not only offers design and structural benefits to build complex-shaped geometries but also contributes to more sustainable construction practices with a lower “cradle-to-gate” carbon footprint due to the reduced material consumption associated with material efficiency.REWAS 2025REWAS 2025: Circular Economy for the Energy Transitio
Circular economy in post consumption network: the role of re-commerce groups in social media platforms
Get PDFThe success of the circular economy transition depends on the involvement of all stakeholders. However, research on consumer participation in the circular economy is limited. This study identifies the micro-level dynamics of the circular economy within the post-consumption network, mainly focusing on re-commerce operations. Through exploring re-commerce networks in 20 countries and a statistical analysis of factors influencing sales performances on Facebook, this research aims to identify the primary elements influencing re-commerce activities on Facebook and their role in promoting circular economy. This study uses grounded theory and a mixed-methods approach, combining literature reviews and interviews, to explore the impact of re-commerce on the circular economy. Based on the research findings, this research develops four propositions to promote future research on post-consumption networks in the circular economy context.Electronic Commerce Research and Application
Glycerol immobilises anaerobic digestate supplied nitrogen
Get PDFAnaerobic digestate, a nutrient rich by-product of the biogas industry, is frequently applied to agricultural land as a fertiliser. However, nitrogen losses from its application negatively impact air and water quality. Therefore, methods are needed to reduce these losses. The aim of this study was to test the efficacy of applying digestate with glycerol, an organic carbon rich by-product of the biodiesel industry, on microbial nitrogen immobilisation and the soil microbial community. Soil was incubated with digestate, applied at a rate equivalent to 250 kg-N ha-1, in a laboratory experiment over 50 days with glycerol additions at either 0, 12, 24 or 36 kg-C m3 of digestate. The addition of glycerol resulted in significantly higher microbial biomass carbon and increased the relative abundance of Gram-negative bacteria. The 24 and 36 kg-C m3 doses of glycerol resulted in similarly greater and longer lasting effect on microbial biomass carbon, indicating that beyond 24 kg-C m3 digestate that nitrogen (or other essential nutrients) became the limiting factor for microbial growth instead of carbon. Soil available nitrogen decreased throughout the study and remained at lower concentrations in glycerol treatments than the digestate only treatment by the end of the study. These results demonstrate that glycerol has the potential to reduce nitrogen losses from digestate application by immobilising nitrogen in the microbial biomass. Therefore, the co-application of digestate and glycerol to soil is a potential mechanism for the biogas and biofuel industries to valorise their respective by-products. Further research is needed to verify that this method is viable under field conditions.Biotechnology and Biological Sciences Research CouncilThis work was funded by Biotechnology and Biological Sciences Research Council, UK, as part of the Food Biosystems DTP, grant number BB/T008776/1, and Future Biogas Ltd.Waste and Biomass Valorizatio
Iron and nitrogen co-doping biochar for simultaneous and efficient adsorption of oxytetracycline and norfloxacin from wastewater
Get PDFThe global proliferation of antimicrobial resistance (AMR) poses a critical challenge to environmental and public health, driven by excessive antibiotic release from medical, agricultural, and aquaculture activities. This study investigates the synthesis and application of Fe/N-doped biochar derived from Enteromorpha clathrata (EC) for the removal of oxytetracycline (OTC) and norfloxacin (NOR) from water. The biochar, synthesized via pyrolysis and NaOH activation, was characterized by BET, SEM, and XPS analyses, revealing a porous structure with enriched functional groups. The EC-derived biochar demonstrated high adsorption capacities for OTC (625.325 mg·g⁻1) and NOR (487.379 mg·g⁻1) under neutral pH conditions, with adsorption following Langmuir and pseudo-second-order models, indicative of monolayer chemisorption. The biochar also exhibited excellent reusability, supporting practical applications. The strong interactions between the FeN4 active sites and the antibiotics were quantified through DFT calculations, showing binding energies of −394.91 kcal/mol for NOR and −398.10 kcal/mol for OTC, highlighting the important role of FeN4 in facilitating efficient adsorption. Additionally, density of states (DOS) analysis revealed that formation of Fe-N/O chemical bonds was confirmed through the hybridization of Fe 3d orbitals with N/O 2p orbitals. Overall, Fe/N-rich biochar contributes to its potential for practical applications in antibiotic removal from aqueous systems.Jiangsu Province Science and Technology Department, Jiangsu Provincial Department of Education, National Natural Science Foundation of ChinaThis work was supported by the Jiangsu Province Outstanding Youth Fund (BK20230012) and the High-performance Computing Platform of Jiangsu University.Industrial Crops and Product
Xylitol production from brewer’s spent grain via Pichia fermentans fermentation: optimization, scaling, and isolation
Get PDFThe primary aim of this study was to investigate the novel application of brewer’s spent grain (BSG), a waste byproduct from the brewing industry, as sustainable and cost‐effective feedstock for xylitol production using the yeast Pichia fermentans. The process encompassed fermentation optimization, scale‐up, and then downstream processing to produce xylitol. Shake flask fermentation was employed to determine optimal conditions, evaluating key parameters including inoculum concentration (12.5%), feedstock (50%), pH (7.0), temperature (30°C), incubation time (96 h), and agitation speed (150 RPM) with a maximum xylitol production of 32.74 g/L. The yield of xylitol increased to 34.57 g/L by scaling up in an 8‐L bioreactor within an incubation time of 72 h. Downstream processing, including centrifugation, charcoal treatment, and ethanol purification was performed successfully, recovering xylitol crystals with a purity of 85.90%. Characterization using X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and high‐performance liquid chromatography (HPLC) confirmed the purity and composition of crystals. This research highlights the economic and environmental advantages of utilizing BSG for xylitol production, offering a sustainable route over conventional substrates.Journal of Food Processing and Preservatio
The temperature dependence of greenhouse gas production from Central African savannah soils
Get PDFSavannahs cover 20 % of the global land surface, but there have been few studies of greenhouse gas (GHG) dynamics from savannah soils. Here, we assess potential turnover of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from surface (0–10 cm) and subsurface (20–30 cm) soils from two contrasting tropical savannah sites in the Republic of Congo, Central Africa, under dry (40 % water-filled-pore-space, WFPS) and wet (70 % WFPS) conditions. Under baseline conditions (25 °C), we found soils were sources of CO2 and N2O, but a sink for CH4. Assessment of the temperature response of GHG fluxes between 20 and 35 °C revealed variable temperature dependences. That is, CO2 fluxes showed a strong temperature response, whereas the temperature response of N2O fluxes was only significant under dry conditions, and no significant temperature response of CH4 fluxes was observed. The temperature quotient (Q10) of soil respiration increased from 1.58 ± 0.004 to 1.92 ± 0.006 at sites with lower soil organic carbon contents. The relative increase in N2O with CO2 fluxes across temperatures was significantly influenced by moisture conditions at both sites. No temperature or soil moisture response was observed for CH4 fluxes, collectively implying divergent GHG responses to changing climatic conditions. Using Rock-Eval pyrolysis we assessed the organic chemistry of all soil types, which indicated contrasting degrees of stability of carbon sources between sites and with depth which, alongside significant differences in a range of other soil parameters (including organic matter content, total carbon, total nitrogen, electrical conductivity, and pH), may account for site-specific differences in baseline GHG emissions. Taken together, our results are amongst the first measures of GHG temperature sensitivity of tropical savannah soils, and demonstrate that soil CO2 emissions are more sensitive to warming and changes in moisture than the emissions of other GHGs, although relatively low compared to responses reported for soils from other tropical ecosystems. This implies that GHG fluxes form savannah soils in the region may be at least partially resilient to climate-induced soil warming compared to other ecosystems.British Geological Survey, Natural Environment Research Council, Royal Geographical Society, Wildlife Conservation SocietyThis work was supported by the Natural Environment Research Council [NE/R016860/1], and Royal Geographical Society (with IBG) [SRG 10/19].Geoderma Regiona
Impact of whale tubercles on the aerodynamics characteristics of F1 front wing - adjoint optimization
No full textThis research aimed to investigate the impact of varying tubercles frequency and amplitudeon the leading edge of a double-element Formula One (F1) front wing at two different ride heights in the pre-stall regime. A bio-inspired tubercle distribution was implemented, varying in amplitude and frequency across the span. Computational simulations were performed at 30m/s using the κ − ω SST model. The results showed that implementing bio-inspired tubercles on front wings did not improve aerodynamic efficiency at any ride height. The clean leading-edge model consistently achieved the highest lift-to-drag ratio at both ride heights. Configurations with various tubercle amplitude presented different results: for low-amplitude tubercles, the down force increased compared to the baseline at the cost of increased drag. Models with higher amplitude tubercles led to significant down force reduction due to flow separation, further diminishing aerodynamic performance. Variations in tubercle frequency had minimal impact on aerodynamic performances. Among the tubercle configurations tested, the model with the lowest amplitude and the fewest tubercles achieved the highest aerodynamic efficiency.AIAA SCITECH 2025 Foru