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Data DrivAer hp-F: Spoiler & Rear Wing Configurations Geometry Pack
No full textCAD geometry files for the 35% scale high-performance DrivAer model (DrivAer hp-F). The dataset includes CAD files for the: - DrivAer hp-F vehicle body, equipped with a 41 mm front bumper splitter, a full set of large forebody strakes, and a 10ยฐ underbody multichannel diffuser. - Rear wing with a NACA 6412 profile, chord of 110 mm, and span of 420 mm. - Spoiler with a plate size of 350 x 80 mm at a 40ยฐ angle of attack - Wheels (stationary and rotating) In reference to the publications: Steven Rijns, Tom-Robin Teschner, Kim Blackburn, Anderson Ramos Proenca, James Brighton; Experimental and numerical investigation of the aerodynamic characteristics of high-performance vehicle configurations under yaw conditions. Physics of Fluids 1 April 2024; 36 (4): 045112. https://doi.org/10.1063/5.0196979 Steven Rijns, Tom-Robin Teschner, Kim Blackburn, James Brighton; Effects of cornering conditions on the aerodynamic characteristics of a high-performance vehicle and its rear wing. Physics of Fluids 1 April 2024; 36 (4): 045119. https://doi.org/10.1063/5.0204204 This geometry pack uses components from the original DrivAer hp-F: the CAD geometry pack collection: Soares, Renan francisco; Olives, Sergio Goรยฑalons; Knowles, Andrew Paul; Garry, Kevin; Holt, Jenny (2018). DrivAer hp-F: the CAD geometry pack. Cranfield Online Research Data (CORD). Collection. https://doi.org/10.17862/cranfield.rd.c.396912
Dataset DrivAer hp-F: Force Measurements in Yaw Conditions
No full textDataset for the aerodynamic force measurements conducted on the 35% scale DrivAer hp-F model at various yaw angles in the 8x6 wind Tunnel at Cranfield University. The dataset includes aerodynamic force coefficients results from measurement on the following vehicle configurations: - DrivAer hp-F standard configuration (no spoiler or rear wing) - DrivAer hp-F spoiler configuration - DrivAer hp-F rear wing configuration The measurements on the DrivAer hp-F rear wing configuration have been conducted three times for repeability. In reference to the publication: Steven Rijns, Tom-Robin Teschner, Kim Blackburn, Anderson Ramos Proenca, James Brighton; Experimental and numerical investigation of the aerodynamic characteristics of high-performance vehicle configurations under yaw conditions. Physics of Fluids 1 April 2024; 36 (4): 045112. https://doi.org/10.1063/5.0196979 CAD files for the DrivAer hp-F configurations are available at: Rijns, Steven; Teschner, Tom-Robin; Blackburn, Kim; Ramos Proenca, Anderson; Brighton, James (2024). DrivAer hp-F: Spoiler & Rear Wing Configurations Geometry Pack. Cranfield Online Research Data (CORD). Dataset. https://doi.org/10.17862/cranfield.rd.2571520
Cellulose-based smart materials: Novel synthesis techniques, properties, and applications in energy storage and conversion devices
Get PDFThere has been a significant scope toward the cutting-edge investigations in hierarchical carbon nanostructured electrodes originating from cellulosic materials, such as cellulose nanofibers, available from natural cellulose and bacterial cellulose. Elements of energy storage systems (ESSs) are typically established upon inorganic/metal mixtures, carbonaceous implications, and petroleum-derived hydrocarbon chemicals. However, these conventional substances may need help fulfilling the ever-increasing needs of ESSs. Nanocellulose has grown significantly as an impressive 1D element due to its natural availability, eco-friendliness, recyclability, structural identity, simple transformation, and dimensional durability. Here, in this review article, we have discussed the role and overview of cellulose-based hydrogels in ESSs. Additionally, the extraction sources and solvents used for dissolution have been discussed in detail. Finally, the properties (such as self-healing, transparency, strength and swelling behavior), and applications (such as flexible batteries, fuel cells, solar cells, flexible supercapacitors and carbon-based derived from cellulose) in energy storage devices and conclusion with existing challenges have been updated with recent findings.Electro
Quaternion-based attitude estimation of an aircraft model using computer vision
Get PDFInvestigating aircraft flight dynamics often requires dynamic wind tunnel testing. This paper proposes a non-contact, off-board instrumentation method using vision-based techniques. The method utilises a sequential process of Harris corner detection, KanadeโLucasโTomasi tracking, and quaternions to identify the Euler angles from a pair of cameras, one with a side view and the other with a top view. The method validation involves simulating a 3D CAD model for rotational motion with a single degree-of-freedom. The numerical analysis quantifies the results, while the proposed approach is analysed analytically. This approach results in a 45.41% enhancement in accuracy over an earlier direction cosine matrix method. Specifically, the quaternion-based method achieves root mean square errors of 0.0101 rad/s, 0.0361 rad/s, and 0.0036 rad/s for the dynamic measurements of roll rate, pitch rate, and yaw rate, respectively. Notably, the method exhibits a 98.08% accuracy for the pitch rate. These results highlight the performance of quaternion-based attitude estimation in dynamic wind tunnel testing. Furthermore, an extended Kalman filter is applied to integrate the generated on-board instrumentation data (inertial measurement unit, potentiometer gimbal) and the results of the proposed vision-based method. The extended Kalman filter state estimation achieves root mean square errors of 0.0090 rad/s, 0.0262 rad/s, and 0.0034 rad/s for the dynamic measurements of roll rate, pitch rate, and yaw rate, respectively. This method exhibits an improved accuracy of 98.61% for the estimation of pitch rate, indicating its higher efficiency over the standalone implementation of the direction cosine method for dynamic wind tunnel testing.Sensor
Suitability analysis for extrusion-based additive manufacturing process
Get PDFAdditive manufacturing (AM) is a widely applied manufacturing paradigm used for the layer-by-layer fabrication of desired components and objects, especially for those with highly intricate geometry. Extrusion-based AM, which is a subcategory of AM processing technologies, is characterized by the facilitation of controlled and successive deposition of feedstock AM materials through the nozzles of printer heads onto a print bed. Extrusion-based AM processing enables design freedom but offers cost efficiency and process simplicity when compared to other AM categories i.e. liquid- and powder-based AM technologies. The extrusion-based AM process has become increasingly widespread over the last two decades because of the expanding material options that can be used in this technology, and its capacity to be hybridised through the addition of multiple printheads or incorporation into a secondary manufacturing system. Despite the promising aspects of the extrusion-based AM process, increasing demands for customised extrusion-based printed products and an expanding range of extrusion-based AM materials create both material- and process-related challenges that limit the suitability of extrusion-based AM processes for some specific applications. Consequently, the principal objective of this review paper is to conduct a suitability analysis of extrusion-based AM processes. The suitability analysis follows a review and discussion about the extrusion-based AM process, and an assessment of easy- and hard-to-print extrusion-based AM materials. This paper, therefore, provides a comprehensive suitability analysis of each extrusion-based AM process while also providing some promising ideas for improving their current suitability levels. The findings and ratings reported in this paper importantly offers viewpoints that would support better futuristic comparisons between developed and developing extrusion-based AM processes, especially as businesses look to adopt the right AM solutions.Additive Manufacturing Frontier
Evaluating resilience of coastal communities upon integrating PRISMA protocol, composite resilience index and analytical hierarchy process
Get PDFThis research intends to investigate the resilience of coastal communities to natural hazards upon adopting: (i) Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol as a novel approach for the selection of resilience indicators and major components; (ii) Analytical Hierarchy Process to generate a weight for each indicator and major component of resilience; and (iii) indexing method to calculate the extent of resilience for each community. The results highlight that 25.81 % of the communities in the study area are registered in the very low to low resilience class, whereas 58.07 % are classified as very high to high. Additionally, this research identifies 11 critical action areas for building resilience in Khulna City, which is crucial for major stakeholders in setting up development strategies and plans for disaster risk reduction and sustainability.International Journal of Disaster Risk Reductio
Integrated numerical and experimental workflow for high-performance vehicle aerodynamics
Get PDFThe high-performance and motorsport vehicle sectors are pushing the performance frontiers of aerodynamically efficient vehicles. Well-balanced use of accurate and consistent numerical simulation tools in combination with wind tunnel experiments is crucial for cost-effective aerodynamic research and development processes. Therefore, this study assesses the simulation performance of four Reynolds-averaged NavierโStokes (RANS) turbulence models in relation to experimental and high-fidelity delayed detached eddy simulation (DDES) data for the aerodynamic assessment of a high-performance variant of the DrivAer model (DrivAer hp-F). The influences of predominant wind tunnel conditions on the vehicleโs aerodynamic force coefficients and flow field are also investigated. Additionally, a novel CFD-based blockage correction method is introduced and applied to evaluate the accuracy of conventional blockage correction methods. Among the RANS models, the k-ฯ SST model exhibited notable relative accuracy in the prediction of force coefficients and demonstrated generally the best correlation with detailed DDES flow field data. The wind tunnel blockage effect caused a 9% increase in downforce and 16% increase in drag, whereas the interference effects from the overhead measurement system reduced downforce by 4% and drag by 8%. The novel CFD-based blockage correction method confirmed that conventional blockage correction methods adequately estimate the dynamic pressure in proximity of a wind tunnel model (<3%), but do not consider local effects on downforce and drag individually. Overall, the research extends beyond prior work on automotive applications, contributing to the advancement of aerodynamic research methodologies suitable for the complex flow fields of high-performance vehicles
Power augmentation and Ramp-Up rate improvement through compressed air Injection: a dry low NOx combustor CFD analysis
Get PDFGas turbines play a key role in accelerating the transition towards more environmentally friendly power generation. This role includes backup of renewable generation that is intermittent, providing grid inertia as well as other ancillary services for grid stability. For quick backup power, the ramp-up rate of gas turbines can be improved through air injection at the back of the compressor, facilitated by integrating compressed air energy storage. Published works have mostly focused on low-fidelity engine system analysis of air injection overall effects. No study has focused on the detailed combustor performance presented in this study. The work shows the impact of air injection on the emissions, thermoacoustic stability and liner wall durability. These yardsticks in assessing the operability of the combustor have also been used for air power augmentation and ramp-up analysis. ANSYS software was used in the computational fluid dynamics (CFD) analysis of the three-dimensional dry low NOx combustor. Low-order models were used for the thermoacoustic stability and durability analysis. For the power augmentation study, the NO and CO emissions produced at 15 % air injection are below the maximum values of the combustor in design operations. Also, the stability and durability were within limits. The ramp-up investigation indicates up to 10 % air injection is allowed and the emissions are similarly acceptable. However, the thermoacoustic analysis shows a potential for combustion instabilities at high frequencies above 1800 Hz. Generally, there was no unusual wall liner durability in these two studies. When benchmarked against previous engine-level analysis, the ramp-up rate can be potentially improved by 54 % if the small concern on thermoacoustic instability is resolved.Applied Thermal Engineerin
The role of numbers, power and status of female corporate directors on gender diversity below the board
Get PDFTurnbull James, Kim - Associate SupervisorThis thesis explores the relationship between women on corporate boards and
the representation of women in the two senior levels below the board. During the
past twenty years there has been considerable efforts to improve the numbers of
women in leadership roles. While there has been significant progress in
developing a critical mass of WoB, it has not had the anticipated effect of
improved gender diversity below the board, where progress has been slow and
has yielded inconsistent results.
Drawing on data from UK FTSE100 companies, this research moves beyond the
trickle-down effect related to critical mass theory and incorporates the constructs
of power and status to examine the relationship of women on boards and women
in the executive levels. The findings suggest that it is the confluence of women
on boards in their numbers, and in positions of power and status that drives
gender diversity below the board.
This thesis makes a number of contributions to knowledge. Taking a
configurational approach using Qualitative Comparative Analysis (QCA), was a
departure from previous research which has mostly relied on the use of traditional
regression analysis. Instead, a QCA embraces casual complexity using a
comparative case-based method to systematically analyze configurations of
conditions and outcomes. The use of this methodology was important in
developing two theoretical contributions. First, it allowed for a more complex
analysis, incorporating the theoretical lens of power and status and womenโs
numerical representation to examine the impact of the gender composition of
corporate boards on gender diversity below the board. The findings provide
empirical evidence that a critical mass of women is not enough on its own to
activate trickle-down mechanism as it is neither necessary nor sufficient in its
association with improved gender diversity in the executive levels. Instead, a
multi theoretic approach results in strong empirical evidence that female directors
on corporate boards, when represented in their numbers, power and status,
indicate gender integrated boards and gender integrated boards are key to
consistently activating the trickle-down effect.
This research also facilitated the development of a board evolution model.
Although speculative, it provides a preliminary hypothesis describing how boards
have evolved from male dominated ones to ones that are not only gender
balanced but gender integrated, where women directors are present in positions
of power and influence.Doctor of Business Administratio
A reduced order model discretisation of the space-angle phase-space dimensions of the Boltzmann transport equation with application to nuclear reactor problems
Get PDFThis article presents a new reduced order model (ROM) for fast solutions to neutron transport problems. The novelty lies in the construction of optimal basis functions spanning the space-angle phase-space dimensions of the Boltzmann transport equation (BTE). It uses Proper Orthogonal Decomposition and the method of snapshots to form the reduced basis, but here a 2-stage construction is proposed that compresses the angle, then space, dimensions sequentially. The approach alleviates the potentially limiting memory burden for BTE-based ROMs by not processing the full discretised solutions of BTE during the construction stage. The model is both accurate and efficient and is demonstrated here for eigenvalue and fixed source reactor physics problems with assumed uncertainties in material cross-section data. Reductions in problem size and solving times exceeds 5 orders of magnitude in comparison to high fidelity models, and which could potentially improve further for larger scale problems.Engineering and Physical Sciences Research Council (EPSRC)We would like to thank the EPSRC for funding this research under the grant EP/M022684/2.Journal of Computational Physic