A Windows program for airfoil design using B-splines

The objective of this thesis has been threefold. First, the formulation of splines has been studied and their development into a computer algorithm has been implemented. Splines represent a powerful concept in computer modeling and geometric representation, for, as parametric curves, they provide a compact way to store the information defining a curve or surface. B-splines have been exclusively used in this thesis, although other types of splines exist. The second goal of this thesis was to learn and utilize C++ as a programming tool in the demonstration of B-spline techniques. C++ was chosen because it is object-oriented, and because it is the chosen language of the Microsoft Windows PC platform. Many languages are object-oriented, but C++ was chosen to make use of its libraries to build standard Windows interfaces and objects. The third piece of this thesis is an effort to explore the fundamentals of inter-language communications. Many old scientific codes are already written in older languages like FORTRAN, so it is advantageous to re-use those codes where possible. Digital Visual FORTRAN, a module of the Microsoft Visual Studio, has provided a powerful tool in their integration of multiple programming languages for Windows applications. Using Visual Studio, it is possible to re-use existing FORTRAN code and envelop it in a C interface using a dynamic link library (DLL) file. This thesis uses a C++ application for defining any typical airfoil using B-splines. The software package calls XFOIL, a code written in FORTRAN to evaluate the aerodynamic characteristics of those airfoils. Further, those characteristics have been compared to those of the original geometry to evaluate the interpolation process used by the splines

GSI Modeling Overview: Requirements for Macroscopic Gas/Surface Interaction Coupling to CFD Codes

An overview is presented of a generalized finite-rate surface chemistry model that has been developed for gas/surface interaction coupling to the Data-Parallel Line-Relaxation (DPLR) code. Species from the gaseous environment are allowed to interact with species adsorbed onto one or more phase of a surface and with one or more phases of a bulk thermal protection system through an arbitrary number of finite-rate reactions. The reactions may include types such as adsorption, desorption, Eley-Rideal recombination, Langmuir-Hinschelwood recombination, partial or total dissociative adsorption, oxidation, reduction, sublimation, or condensation where forward and reverse rates are constrained by thermodynamics. A simple pyrolysis model is incorporated into the gas species mass balance and energy balance boundary conditions where the pyrolysis production may be specified explicitly from an uncoupled material response analysis or assumed steady-state proportionality to the bulk phase ejection rate. The production rates of all gaseous species are implicitly coupled into the viscous wall boundary condition of the DPLR code to maximize the convergence rate of the solver. Examples are shown for a catalysis system and a TPS system to demonstrate the model. The focus of the work presented is primarily to demonstrate the necessary model, reaction, surface, and material data required

Reactionary Populism and the Historical Erosion of Democracy in America. An Interview with Nancy MacLean, Duke University

Nancy MacLean is the William H. Chafe Professor of History and Public Policy at Duke University, and the award-winning author of several books, including Behind the Mask of Chivalry: The Making of the Second Ku Klux Klan; Freedom is Not Enough: The Opening of the American Workplace; The American Women’s Movement, 1945-2000: A Brief History with Documents; and Debating the American Conservative Movement: 1945 to the Present. She also served the editor of Scalawag: A White Southerner’s Journey through Segregation to Human Rights Activism. Her scholarship has received more than a dozen major prizes and awards, and has been supported by fellowships from the American Council of Learned Societies, the National Endowment for the Humanities, the National Humanities Center, the Russell Sage Foundation, and the Woodrow Wilson National Fellowships Foundation. Her most recent book is Democracy in Chains: The Deep History of the Radical Right’s Stealth Plan for America. Democracy in Chains was a finalist for the National Book Award, and the winner of the Los Angeles Times Book Award in Current Affairs, the Lannan Foundation Cultural Freedom Award, and the Lillian Smith Book Award. The Nation magazine named it the “Most Valuable Book” of the year

Understanding High Recession Rates of Carbon Ablators Seen in Shear Tests in an Arc Jet

High rates of recession in arc jet shear tests of Phenolic Impregnated Carbon Ablator (PICA) inspired a series of tests and analysis on FiberForm (a carbon preform used in the fabrication of PICA). Arc jet tests were performed on FiberForm in both air and pure nitrogen for stagnation and shear configurations. The nitrogen tests showed little or no recession, while the air tests of FiberForm showed recession rates similar to that of PICA (when adjusted for the difference in density). While mechanical erosion can not be ruled out, this is the first step in doing so. Analysis using a carbon oxidation boundary condition within DPLR was used to predict the recession rate of FiberForm. The analysis indicates that much of the anomalous recession behavior seen in shear tests may simply be an artifact of the non-flight like test configuration (copper upstream of the test article) a result of dissimilar enthalpy and oxygen concentration profiles on the copper. Shape change effects were also investigated and shown to be relatively small

Space Launch System Base Heating Test: Experimental Operations & Results

NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Test methodology and conditions are presented, and base heating results from 76 runs are reported in non-dimensional form. Regions of high heating are identified and comparisons of various configuration and conditions are highlighted. Base pressure and radiometer results are also reported

Scaled Rocket Testing in Hypersonic Flow

NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was strongly based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Detailed base heating results are outside of the scope of the current work, rather test methodology and techniques are presented along with broader applicability toward scaled rocket testing in supersonic and hypersonic flow

Fit for LIFE:the development and optimization of an intervention delivered through prison gymnasia to support incarcerated men in making positive lifestyle changes

Background: Despite prison settings presenting opportunities for healthy eating and regular exercise, many incarcerated men supplement prison food with unhealthy snacks and drinks, and are less likely to achieve recommended physical activity guidelines than non-incarcerated men. This paper describes the co-development with prison staff of a healthy lifestyle intervention for delivery to incarcerated men, and feasibility testing of its delivery through prison physical education departments. Methods: The starting point for intervention development was Football Fans in Training (FFIT), an evidence-based intervention successful in engaging men and supporting them to lose weight, make positive lifestyle changes and maintain these long term. We iteratively tested and adapted FFIT for delivery in prison gym facilities through a four Phase pilot and optimisation study. Methods used to evaluate each phase included: observations of session deliveries; semi-structured interviews with participants; and a focus group/semi-structured interviews with prison Physical Education Instructors (PEIs) who delivered the programme. Data were analysed thematically using the Framework approach. Findings from each phase informed development of the optimised programme. Results: We iteratively co-developed a healthy lifestyle intervention (known as Fit for LIFE) tailored to the needs of incarcerated men and prison operational constraints. Fit for LIFE comprises elements specifically designed to address common barriers to a healthy lifestyle within prison, including: discussion of healthiest available food choices; trying out different physical activity options in the prison gym; and strategies (such as in-cell workouts) for dealing with prolonged time in cells at evenings/weekends. Weight loss was not always the most valued outcome. Instead, participants cited a wide range of behavioural, physical and mental health improvements as important to them, and were more motivated if they could focus on identifying and achieving personally relevant objectives. Conclusions: Fit for LIFE is a 10-week, group-based healthy lifestyle programme tailored for delivery to incarcerated men in prison gymnasia. Weekly 90-min sessions include informative and interactive ‘classroom’ activities followed by a practical physical activity training session, often with group activities. Fit for LIFE aims to help incarcerated men to: increase physical activity; reduce sedentary time; eat more healthily; and start and maintain using prison gym facilities with confidence

Citizen science as a new tool in dog cognition research

The work of Á.M. was supported by the Hungarian Academy of Sciences (MTA 01 031).Family dogs and dog owners offer a potentially powerful way to conduct citizen science to answer questions about animal behavior that are difficult to answer with more conventional approaches. Here we evaluate the quality of the first data on dog cognition collected by citizen scientists using the Dognition. com website. We conducted analyses to understand if data generated by over 500 citizen scientists replicates internally and in comparison to previously published findings. Half of participants participated for free while the other half paid for access. The website provided each participant a temperament questionnaire and instructions on how to conduct a series of ten cognitive tests. Participation required internet access, a dog and some common household items. Participants could record their responses on any PC, tablet or smartphone from anywhere in the world and data were retained on servers. Results from citizen scientists and their dogs replicated a number of previously described phenomena from conventional lab-based research. There was little evidence that citizen scientists manipulated their results. To illustrate the potential uses of relatively large samples of citizen science data, we then used factor analysis to examine individual differences across the cognitive tasks. The data were best explained by multiple factors in support of the hypothesis that nonhumans, including dogs, can evolve multiple cognitive domains that vary independently. This analysis suggests that in the future, citizen scientists will generate useful datasets that test hypotheses and answer questions as a complement to conventional laboratory techniques used to study dog psychology.Publisher PDFPeer reviewe

Using false discovery rates to benchmark SNP-callers in next-generation sequencing projects

Funding: R.A.F. was funded by the Natural Environment Research Council (NERC). D.A.H. and M.C.F. were supported by the Wellcome Trust. No additional external funding received for this study.Peer reviewedPublisher PD

Turbulent Aeroheating Measurements on a 7-deg Half-Angle Sphere-Cone in a High-Enthalpy CO2 Expansion Tunnel

A database of heating and pressure measurements on a 7-deg half-angle cone in a highenthalpy expansion tunnel in CO2 has been generated to support development and validation of computational models to be employed in the design of future Mars missions. Laminar, transitional, and turbulent simulations were performed at the test conditions for comparisons with the data. Close agreement was obtained for both fully-laminar and fully turbulent conditions. For the remaining transitional/turbulent conditions, agreement to within, or slightly more than, the estimated experimental uncertainty was demonstrated. The influence of transition intermittency and transition length models on predicted heating levels was demonstrated, as were differences in turbulent heating predictions generated using various algebraic, one-equation, and two-equation turbulence models. These comparisons provide some measure of confidence in turbulent simulation capabilities; however, because the data were not obtained on a relevant entry vehicle geometry, it is not possible to fully quantify computational uncertainties for the definition of Mars mission aerothermodynamic environments at this tim