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Uncertainty propagation and management of mixed uncertainties for multi-fidelity multi-disciplinary analysis of propeller with different blade sweep
Get PDFA study on the uncertainty quantification and propagation in a multi-fidelity, multi-disciplinary framework, focusing on aerodynamics, aeroacoustics, and aeroelasticity in propeller blade design is presented. Employing the Lattice Boltzmann Method (LBM) for high-fidelity simulations and the Lifting Line Free Vortex Wake (LLFVW) and Finite Element Analyses (FEA) for mid-fidelity simulations, the study analyzes a 2-bladed, 0.3m diameter propeller using NACA4412 airfoil cross-section, across nine blade sweep configurations. It investigates the effects of two uncertain parameters: freestream velocity, using Interval analysis, and blade tip offset, using Monte Carlo Simulation. The differential analysis between mid and high-fidelity methods shows an uncertainty range of 13.83% to 30.32% for freestream velocity and 2% to 32.48% for blade tip offset, due to the inclusion of the mid-fidelity method. Using the Halton sampling method, it is demonstrated that the uncertainty in the sweep parameter is propagated differently across various performance metrics of the propeller. A backward sweep tends to increase both the mean (by 5-6 %) and uncertainty (by 2-4 %) in all performance parameters, suggesting a potential enhancement in performance but with increased risk. In contrast, a forward sweep reduces mean performance (by 2-3 %) and uncertainty (by 4-6 %) of all parameters except structural deflection, which shows an increasing trend (by 0.5-2 %). This indicates a more reliable aerodynamic and aeroacoustic performance but potentially less efficient operation and increased risk in structural integrity.This project has received funding from Innovate UK under Grant Agreement No 10003388AIAA SCITECH 2024 Foru
Sewage fungus occurrence in English rivers
No full textThe dataset contains the location and date (month/year) of sewage fungus observed in rivers by Environment Agency environment officers (2000-2020). The data were obtained via a standard data request to the Environment Agency. Spatial locations were limited to a 10 x 10 km resolution by the Environment Agency, and no information was provided on the river or pollution source, to comply with their data protection rules.Central England NERC Training Alliance (CENTA
Control of an over-actuated fixed-wing vectored thrust eVTOL
Get PDFA novel full-envelope controller for an over-actuated fixed-wing vectored thrust eVTOL aircraft is presented. It proposes a generic control architecture applicable to piloted, semi-automatic and fully-automated flight consisting of an aircraft-level controller (high-level controller) and a control allocation scheme. The aircraft-level controller consists of a main inner-loop non-linear dynamic inversion controller and an outer-loop proportional-integral linear controller. The inner-loop classical non-linear dynamic inversion controller is used for forward cruise flight while the outer-loop proportional-integral linear controller is used for hover/low speed control and position control. The control allocation scheme uses a novel architecture which transfers the non-linearity in the vectored thrust effector model formulation to the computation of the actuator limits by converting the effector model from polar to rectangular form thus allowing the use of a linear optimisation technique. The linear optimisation technique is an Active Set Linear Quadratic Programming constrained optimisation algorithm with a weighted least squares formulation. The control allocation allocates the overall control demand (virtual controls) to individual redundant effectors while performing control error minimisation, control channel prioritization and control effort minimization. Simulation results shows forward transition from hover to cruise and clearly demonstrates that the controller can handle saturation (position or rate). The proposed controller can also handle actuator failures.2024 UKACC, 14th International Conference on Control (CONTROL
Characterisation of Wire Arc Additive Manufactured Superalloys
No full textCharacterisation of two superalloys to understand the response of Wire Arc Additive Manufactured (WAAM) superalloys for high temperature applications. With an aim to understand if machine hammer peening (MHP) can be used to obtain a performance similar to the wrought alloys.Defence Science and Technology Laboratory (DSTL
Characterizing China's road network development from a spatial entropy perspective
No full textUnderstanding the spatial characteristics of road networks is crucial for the planning of road networks. Although road networks have been frequently evaluated in combination with various socioeconomic factors, the current road network development in developing countries still needs to be better understood. Combining road network density and spatial entropy for 2728 counties in China, we provide a comprehensive assessment of road networks and their key influencing factors. Our results indicate a significant spatial heterogeneity of the road network development, especially on both sides of the Heihe-Tengchong line. Demographic-economic and topographic variables jointly explained 54.2% and 65.1% of the spatial variations in road network density and entropy, respectively. Road entropy increases with road network density in line with a saturation curve from provincial to national scales, which offers guidance for future road planning. Using a K-means clustering analysis, we categorized China's road networks into four groups corresponding to the development stages. Our findings improve the current understanding of road network development in China and provide important implications for national road network planning in the future.This work was supported by the National Natural Science Foundation of China (31988102)Journal of Transport Geograph
Commentary:- Can I use that tool?
Get PDFThe decision as to whether a given tool can be used for the purposes of conducting a digital forensic examination of a device and its data may seem straightforward, but it is not. As part of their work, practitioners must always seek to identify and use tools that are appropriate for their investigative tasks, deploy them reliably within an applicable scenario, and be able to trust and understand the results that they provide. Before they can begin to do this, they must first ask themselves the question - ‘can I use that tool?‘, where this work considers how a practitioner may begin to formulate an answer. By unpacking the hidden complexity of this question, it is suggested that five sub-questions must be explored by any practitioner when seeking to use a tool, namely - (1) ‘what does that tool do?‘; (2) ‘how do I use that tool?‘; (3) ‘how does the tool do it?‘; (4) ‘does the tool do it properly?’ and (5) ‘should I use the tool?‘. This work discusses each in turn and the risks they pose to a practitioner.Forensic Science International: Digital Investigatio
Thermodynamic analysis of decarbonizing NGCC power plants by the tail-end green ammonia-driven calcium looping
Get PDFThis work proposes a novel ammonia driven tail-end calcium looping (CaL) process to capture carbon emission from natural gas combined cycle (NGCC) power plants for net-zero energy. Two integration schemes are introduced, including sensible heat thermochemical recuperation (SHTR) and carbonation heat thermochemical recuperation (CHTR) driven by combustion of partially cracked ammonia as a zero-carbon fuel. Results show that energy penalties can be reduced from 9.6 % in the NGCC power plant with the CaL-Oxy method to 1.8 % in the SHTR scheme and 1.4 % in the CHTR scheme, respectively. Comparing with the NGCC base power plant and the NH3-based thermochemical recuperation power plant, energy savings can be achieved at 5.44 MJLHV/kg CO2 in the SHTR scheme and 6.73 MJLHV/kg CO2 in the CHTR scheme. Additionally, exergy analysis shows that the reduction of exergy destruction in the carbonation and calcination processes determines the thermodynamic performance enhancement. Cascaded heat recovery of carbonation heat and the heating supply method of calcination narrow the energy level difference, contributing to the reduction of exergy destruction. Sensitivity analysis indicates that reorganizing a more efficient thermodynamic cycle can offset the energy consumption of CO2 capture from flue gas, resulting in an optimized negative energy penalty at −0.8 %.This work was supported by grants from Natural Science Foundation of Guangdong Province (No. 2024A1515012661), and Guangzhou Basic and Applied Basic Research Foundation (No. 2024A04J3828), Engineering and Physical Sciences Research Council, UK (EP/X03593X/1), and China Postdoctoral Science Foundation (No. 2024T170587, No. 2024M752134).Energ
Sensing spatial inequality of socio-economic factors for deploying permanent deacons in the UK
Get PDFIntegrating spatial inequality perspectives in strategic decision-making can ensure positive impacts on resource distribution for public welfare and sustainable development. This study aims to apply evidence-based approaches in deploying permanent deacons. The empirical case study has been conducted at the St Helens denary of the Liverpool archdiocese, UK. Assisting with charitable works is one of three served areas by the Roman Catholic Church facilitated by deacons. The deployment of permanent deacons could benefit from being evidence-based so that a deacon can serve to ease the socio-economic (e.g., population density, long-term health conditions, housing system, employment status, education level, social status) inequality in the most deprived area. We used geographic information system (GIS) based algorithms, Getis-Ord Gi* for hot spot analysis to find the clustered area by considering the socio-economic factors. The open/freely available government census dataset was found to help extract socio-economic parameters. Furthermore, a GIS-based multi-criteria assessment technique was conducted by applying map algebra (raster calculator) to identify the deprived area with ranks considering multiple socio-economic conditions, where served areas by the existing deacons were considered to constrain. The served areas were estimated by applying network analysis where OpenStreetMap and location existing deacons were used as input. Our empirical case study identified the central and northern parts of the deanery as the most and least deprived areas, respectively. Finally, Liverpool archdiocese could consider deploying new permanent deacons in St Helens denary based on suggested deprivation ranks. Therefore, the appropriate number of deacons in the deprived areas can quickly and effectively respond to the needy and enhance communities’ resilience and sustainable development by ensuring proportionate resource distribution.PorticusThis research was run under the Ministry Research Project in collaboration with Liverpool Hope University and Liverpool Archdiocese, funded by Porticus Trust (https://www.porticus.com/).Frontiers in Sociolog
Dataset for "Application of Spatial Offset Raman Spectroscopy (SORS) and Machine Learning for Sugar Syrup Adulteration Detection in UK Honey"
No full textHoney authentication is a complex process which traditionally requires costly and time-consuming analytical techniques not readily available to the
producers. The aim of this study was to develop non-invasive sensor methods coupled with multivariate data analysis for de-tecting the type and percentage
of exogenous sugar adulteration in UK honeys. For this purpose, we employed through-container Spatial Offset Raman Spectroscopy (SORS) on 17 different
types of natural honeys produced in the UK over the course of a season and the same honey samples spiked with rice and sugar beet syrups at levels 10%,
20%, 30%, 50% w/w. The data acquired were used to construct prediction models for 14 types of honey with similar Raman fingerprint using different
algorithms, namely PLS-DA, XGBoost and Random Forest with the aim to detect the level of adulteration per type of sugar syrup. The best performing
algorithm for classification was Random Forest with only 1% of the pure honeys misclassified as adulterated and < 3.5% of adulterated honey samples
misclassified as pure. Random Forest was further employed to create a classification model which successfully classified samples according to the type of
adulterant (rice or sugar beet) and the adulteration level. In addition, we collected SORS spectra from 27 samples of heather honey (24 Calluna vulgaris and 3
Erica Cinerea) produced in the UK and cor-responding subsamples spiked with high fructose sugar cane syrup and performed exploratory data analysis with
PCA and classification with Random Forest which both showed a clear sepa-ration between pure and adulterated samples at medium (40%) and high (60%)
adulteration levels and a 90% success at low adulteration levels (20%). The results of this study demonstrate the potential of SORS in combination with
machine learning to be applied for the authentication of honey samples and the detection of exogenous sugars in the form of sugar syrups. A major advantage
of the SORS technique is that it is a rapid, non-invasive method deployable in field with potential application at all stages of the supply chain.Innovate U
AI-driven multidisciplinary conceptual design of unmanned aerial vehicles
Get PDFThis paper presents a multidisciplinary conceptual design framework for unmanned aerial
vehicles based on artificial intelligence-driven analysis models. This approach leverages AI-
driven analysis models that include aerodynamics, structural mass, and radar cross-section
predictions to bring quantitative data to the initial design stage, enabling the selection of the
most appropriate configuration from various optimized concept designs. Due to the design
optimization cycle, the initial dimensions of key components such as the wing, tail, and fuselage
are provided more accurately for later design activities. Simultaneously, the generated structure
enables more suitable design point selection through the feedback loop within the design
iteration. Therefore, in addition to reducing design costs, this approach also offers a substantial
time advantage in the overall design process.AIAA SCITECH 2024 Foru