Simulating the aerodynamic characteristics of the Land Speed Record vehicle BLOODHOUND SSC

This paper describes the application of a parallel finite-volume compressible Navier–Stokes computational fluid dynamics solver to the complex aerodynamic problem of a land-based supersonic vehicle, BLOODHOUND SSC. This is a complex aerodynamic problem because of the supersonic rolling ground, the rotating wheels and the shock waves in close proximity to the ground. The computational fluid dynamics system is used to develop a mature vehicle design from the initial concept stage, and the major aerodynamic design changes are identified. The paper’s focus, however, is on the predicted aerodynamic behaviour of the finalised (frozen) design which is currently being manufactured. The paper presents a summary of the data bank of predicted aerodynamic behaviours that will be used as the benchmark for vehicle testing and computational fluid dynamics validation throughout 2015 and 2016 in an attempt to achieve a Land Speed Record of 1000 mile/h (approximately Mach 1.3). The computational fluid dynamics predictions indicate that the current design has a benign lift distribution across the whole Mach range of interest and a sufficiently low drag coefficient to achieve this objective. It also indicates that the fin is sized appropriately to achieve the static margin requirements for directional stability. The paper concludes by presenting the impact of feeding the detailed computational fluid dynamics predictions into the overall vehicle performance model together with recommendations for further computational fluid dynamics study

Enhancing Undergraduate Teaching and Feedback using Social Media – an Engineering Case Study

For large modules taught within the College of Engineering at Swansea University such as the level 1 module Scientific & Engineering Skills (EG168) and Engineering Analysis (EG189/190), it is a considerable challenge for the lecturer(s) to develop a meaningful relationship with students. Lecture cohorts on these modules are large (250+ students) and examples are delivered through smaller classes (~50 students) and laboratory sessions by supplementary lecturers and/or postdoctoral researchers. This inevitably leads to a certain lack of continuity with regards to students’ contact with the lecturer. It also places a significant pressure on ‘office hours’ and email.This paper details a project aimed at tackling this problem by establishing an online community, using the social networking facility ‘twitter’ to connect students to the lecturer, who was able to drip feed examples to students in the form of online video ‘mini lectures’ posted and discussed via twitter. It will be argued thatthis not only allowed an enhanced sense of affinity and belonging within the module cohort, but also improved real time feedback for the lecturer who was able to adjust future lecture content based on the feedback being received via twitter.This technique was initially trialled on the EG168 Scientific and Engineering Skills module: a very large module ( 550 students) taken by all level 1 engineers (and Sports Science students) in the first term of their degree at Swansea University. One of the aims of this module in recent deliveries has been to try and tailor examples to specific engineering disciplines whilst delivering generic content to the whole cohort through large lectures. It will be shown that delivery of online multimedia discipline-specific examples to students via the web (posted and discussed using twitter) enhanced our ability to achieve this.The fundamental raison d’etre of this project was and is to embrace Benjamin Franklin’s famous philosophy:’Tell me and I forget, Teach me and I remember, Involve me and I learn.

High order parallelisation of an unstructured grid, discontinuous-Galerkin finite element solver for the Boltzmann–BGK equation

This paper outlines the implementation and performance of a parallelisation approach involving partitioning of both physical space and velocity space domains for finite element solution of the Boltzmann-BGK equation. The numerical solver is based on a discontinuous Taylor–Galerkin approach. To the authors' knowledge this is the first time a ‘high order’ parallelisation, or `phase space parallelisation', approach has been attempted in conjunction with a numerical solver of this type. Restrictions on scalability have been overcome with the implementation detailed in this paper. The developed algorithm has major advantages over continuum solvers in applications where strong discontinuities prevail and/or in rarefied flow applications where the Knudsen number is large. Previous work by the authors has outlined the range of applications that this solver is capable of tackling. The paper demonstrates that the high order parallelisation implemented is significantly more effective than previous implementations at exploiting High Performance Computing architectures

Creating music in the classroom with tablet computers: An activity system analysis of two secondary school communities.

Tablet computers are becoming inextricably linked with innovation and change in schools. Increasingly therefore, music teachers must consider how tablet computers might influence creative musical development in their own classroom. This qualitative research into two secondary school communities aims to develop understandings about what really happens when students and a music teacher-researcher compose music in partnership with a tablet computer. A sociocultural definition of creativity, theories of Activity, and the musicking argument inform a new systemic framework which guides fieldwork. This framework becomes the unit of analysis from which the research questions and a multi-case, multimodal methodology emerge. The methodology developed here honours the situated nature of those meanings which emerge in each of the two school communities. Consequently, research findings are presented as two separate case reports. Five mixed-ability pairs are purposively sampled from each community to represent the broad range of musical experience present in that setting. A Video-enhanced, participant-observation method ensures that systemic, multimodal musicking behaviours are captured as they emerge overtime. Naturalistic group interviewing at the end of the project reveals how students’ broader musical cultures, interests and experiences influence their tablet-mediated classroom behaviour. Findings develop new understandings about how tablet-mediated creative musical action champions inclusive musicking (musical experience notwithstanding) and better connects the music classroom and its institutional requirements with students’ informal music-making practices. The systems of classroom Activity which emerge also compensate for those moments when the tablet attempts to overtly determine creative behaviour or conversely, does not do enough to ensure a creative outcome. In fact, all system dimensions (e.g. student partner/teacher/student/tablet) influence tablet- mediated action by feeding the system with musical and technological knowledge, which was also pedagogically conditioned. This musical, technological and pedagogical conditioning is mashed-up, influencing action just-in-time, according to cultural, local and personal need. A new method of visual charting is developed to ‘peer inside’ these classroom-situated systems. Colour-coded charts evidence how classroom musicians make use of and synthesize different system dimensions to find, focus and fix their creative musical ideas over time. There are also implications for research, policy and practice going forward. In terms of researching digitally-mediated creativity, a new social-cultural Activity framework is presented which encourages researchers to revise their definition of creativity itself. Such a definition would emphasise the role of cultural, local and personal constraint in creative musical development. With reference to classroom practice, this research discovers that when students partner with tablet computers, their own musical interests, experiences and desires are forwarded. Even though these desires become fused with institutional requirements, students take ownership of their learning and are found rightfully proud of their creative products. This naturalistic, community-driven form of tablet- mediated creative musical development encourages policy makers and teachers to reposition the music classroom: to reconnect it with the local community it serves

Computational aerodynamic optimisation of vertical axis wind turbine blades

The approach and results of a parametric aerodynamic optimisation study is presented to develop the blade design for a novel implementation of a vertical axis wind turbine. It was applied to optimise the two-dimensional cross-sectional geometry of the blades comprising the turbine. Unsteady viscous computational fluid dynamic simulations were used to evaluate blade performance. To compare geometries, the non-dimensional Coefficient of Power was used as a fitness function. Moving meshes were used to study the transient nature of the physical process. A new parameterisation approach using circular arcs has been developed for the blade cross sections. The optimisation process was conducted in two stages: firstly a Design of Experiments based response surface fitting was used to explore the parametric design space followed by the use of a Nelder-Mead simplex gradient-based optimisation procedure. The outcome of the optimisation study is a new blade design that is currently being tested in full-scale concept trials by a partnering wind energy company

Microevolution in the major outer membrane protein OmpA of Acinetobacter baumannii

Acinetobacter baumannii is nowadays a relevant nosocomial pathogen characterized by multidrug resistance (MDR) and concomitant difficulties to treat infections. OmpA is the most abundant A. baumannii outer membrane (OM) protein, and is involved in virulence, host-cell recognition, biofilm formation, regulation of OM stability, permeability and antibiotic resistance. OmpA members are two‐domain proteins with an N‐terminal eight‐stranded β‐barrel domain with four external loops (ELs) interacting with the environment, and a C‐terminal periplasmic domain binding non‐covalently to the peptidoglycan. Here, we combined data from genome sequencing, phylogenetic and multilocus sequence analyses from 975 strains/isolates of the Acinetobacter calcoaceticus/Acinetobacter baumannii complex (ACB), 946 from A. baumannii, to explore ompA microevolutionary divergence. Five major ompA variant groups were identified (V1 to V5) in A. baumannii, encompassing 52 different alleles coding for 23 different proteins. Polymorphisms were concentrated in five regions corresponding to the four ELs and the C‐terminal end, and provided evidence for intra‐genic recombination. ompA variants were not randomly distributed across the A. baumannii phylogeny, with the most frequent V1(lct)a1 allele found in most clonal complex 2 (CC2) strains and the second most frequent V2(lct)a1 allele in the majority of CC1 strains. Evidence was found for assortative exchanges of ompA alleles not only between separate A. baumannii lineages, but also different ACB species. The overall results have implications for A. baumannii evolution, epidemiology, virulence and vaccine design

On an Exact Step Length in Gradient-Based Aerodynamic Shape Optimization

This study proposeda novel exact expression for step length (size) in gradient-based aerodynamic shape optimization for an airfoil in steady inviscid transonic flows. The airfoil surfaces were parameterized using Bezier curves. The Bezier curve control points were considered as design variables and the finite-difference method was used to compute the gradient of the objective function (drag-To-lift ratio) with respect to the design variables. An exact explicit expression was derived for the step length in gradient-based shape optimization problems. It was shown that the derived step length was independent of the method used for calculating the gradient (adjoint method, finite-difference method, etc). The obtained results reveal the accuracy of the derived step length

On an Exact Step Length in Gradient-Based Aerodynamic Shape Optimization—Part II: Viscous Flows

This study presents an extension of a previous study (On an Exact Step Length in Gradient-Based Aerodynamic Shape Optimization) to viscous transonic flows. In this work, we showed that the same procedure to derive an explicit expression for an exact step length in a gradient-based optimization method for inviscid transonic flows can be employed for viscous transonic flows. The extended numerical method was evaluated for the viscous flows over the transonic RAE 2822 airfoil at two common flow conditions in the transonic regime. To do so, the RAE 2822 airfoil was reconstructed by a Bezier curve of degree 16. The numerical solution of the transonic turbulent flow over the airfoil was performed using the solver ANSYS Fluent (using the Spalart–Allmaras turbulence model). Using the proposed step length, a gradient-based optimization method was employed to minimize the drag-to-lift ratio of the airfoil. The gradient of the objective function with respect to design variables was calculated by the finite-difference method. Efficiency and accuracy of the proposed method were investigated through two test cases