bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiscale Parallelized Computational Fluid Dynamics Modeling Toward Resolving Manufacturable Roughness
Authors: Kapsis Marios , He Li , Li Yan Sheng , Valero Omar , Wells Roger , Krishnababu Senthil , Gupta Gaurav , Kapat Jayanta , Schaenzer Megan 
Published: November 2019

Abstract
Typical turbomachinery aerothermal problems of practical interest are characterized by flow structures of wide-ranging scales, which interact with each other. Such multiscale interactions can be observed between the flow structures produced by surface roughness and by the bulk flow patterns. Moreover, additive manufacturing (AM) may sooner or later open a new chapter in the way components are designed by granting designers the ability to control the shape and patterns of surface roughness. As a result, surface finish, which so far has been treated largely as a stochastic trait, can be shifted to a set of design parameters that consist of repetitive, discrete micro-elements on a wall surface (“manufacturable roughness”). Considering this prospective capability, the question would arise regarding how surface microstructures can be incorporated in computational analyses during designing in the future. Semi-empirical methods for predicting aerothermal characteristics and the impact of manufacturable roughness could be used to minimize computational cost. However, the lack of element-to-element resolution may lead to erroneous predictions, as the interactions among the roughness micro-elements have been shown to be significant for adequate performance predictions (Kapsis and He, 2018, “Analysis of Aerothermal Characteristics of Surface Micro-Structures,” ASME J. Fluids Eng., 140(5), p. 051104). In this paper, a new multiscale approach based on the novel block spectral method (BSM) is adopted. This method aims to provide efficient resolution of the detailed local flow variation in space and time of the large-scale microstructures. This resolution is provided without resorting to modeling every single ones in detail, as a conventional large-scale computational fluid dynamics (CFD) simulation would demand, but still demonstrating similar time-accurate and time-averaged flow properties. The main emphasis of this work is to develop a parallelized solver of the method to enable tackling large problems. The work also includes a first of the kind verification and demonstration of the method for wall surfaces with a large number of microstructured elements.
Enhanced Delayed Detached Eddy Simulation for Cavities and Labyrinth Seals
Authors: Jefferson-Loveday Richard J. 
Published: November 2019

AbstractA range of popular hybrid Reynolds-averaged Navier–Stokes -large eddy simulation (RANS-LES) methods are tested for a cavity and two labyrinth seal geometries using an in-house high-order computational fluid dynamics (CFD) code and a commercial CFD code. The models include the standard Spalart–Allmaras (SA) and Menter shear stress transport (SST) versions of delayed detached eddy simulation (DDES) and the Menter scale adaptive simulation (SAS) model. A recently formulated, enhanced, variant of SA-DDES presented in the literature and a new variant using the Menter SST model are also investigated. The latter modify the original definition of the subgrid length scale used in standard DDES based on local vorticity and strain. For all geometries, the meshes are considered to be hybrid RANS-LES adequate. Very low levels of resolved turbulence and quasi-two-dimensional flow fields are observed for the standard DDES and SAS models even for the test cases here that contain obstacles, sharp edges, and swirling flow. Similar findings are observed for both the commercial and in-house high-order CFD codes. For the cavity simulations, when using standard DDES and SAS, there is a significant under prediction of turbulent statistics compared with experimental measurements. The enhanced versions of DDES, on the other hand, show a significant improvement and resolve turbulent content over a wide range of scales. Improved agreement with experimental measurements is also observed for profiles of the vertical velocity component. For the first labyrinth seal geometry swirl velocities are more accurately captured by the enhanced DDES versions. For the second labyrinth seal geometry, the mass flow coefficient prediction using the enhanced models is significantly improved (up to 30%). Standard, industrially available hybrid RANS-LES models, when applied to the present canonical cases can produce little to no resolved turbulent content. The standard SA- and Menter-based DDES models can yield lower levels of eddy viscosity when compared to equivilent steady RANS simulations which means that they are not operating as RANS or LES. It is recommended that hybrid RANS-LES models should be extensively tested for specific flow configurations and that special care is exercised by CFD practitioners when using many of the popular hybrid RANS-LES models that are currently available in commercial CFD packages.
Effect of Internal Air Flow on Local Postweld Heat Treatment for Large Diameter ASME P92 Steel-Welded Pipes
Authors: Hu Lei , Yu Shumin , Ma Qunshuang , Cui Bing , Zhang Zhenyu , Zhu Chen 
Published: November 2019

Abstract
Local postweld heat treatment (PWHT) is usually employed in field fabrication of large-sized ASME SA-335 Grade P92 steel pipes. Internal air flow in pipes that arise from field fabrication can result in considerable convection losses on the inside surface of the pipe when the pipe is not strictly sealed off. Welding and local PWHT experiments of a large diameter P92 steel pipe were conducted both with and without internal air flow, and temperature field of both sides of the pipe was measured. The conjugate heat transfer between the pipe and the internal air is simulated using computational fluid dynamics (CFD) method. The effect of internal air flow on temperature field was further investigated. Results indicate that temperature gradient along through-thickness direction and axial direction during local PWHT is significantly increased due to internal air flow. The increasing rate of temperature difference between inner and outer surface at weld centerline to internal air velocity is about 14.5 °C/(m s−1). The maximum temperature is no longer located at the weld centerline, which will lead to a risk of overheating. The temperature drop is severer in the air inlet side than air outlet side at same distance from weld centerline. For local PWHT to be successful, the internal air flow should be strictly limited during local PWHT; otherwise, the width of heated band (HB) should be extended.
Simultaneous Kinematic and Contact Force Modeling of a Human Finger Tendon System Using Bond Graphs and Robotic Validation
Authors: Tigue James A. , King Raymond J. , Mascaro Stephen A. 
Published: November 2019

AbstractThis paper aims to use bond graph modeling to create the most comprehensive finger tendon model and simulation to date. Current models are limited to either free motion without external contact or fixed finger force transmission between tendons and fingertip. The forward dynamics model, presented in this work, simultaneously simulates the kinematics of tendon-finger motion and contact forces of a central finger given finger tendon inputs. The model equations derived from bond graphs are accompanied by nonlinear relationships modeling the anatomical complexities of moment arms, tendon slacking, and joint range of motion (ROM). The structure of the model is validated using a robotic testbed, Utah's Anatomically correct Robotic Testbed (UART) finger. Experimental motion of the UART finger during free motion (no external contact) and surface contact are simulated using the bond graph model. The contact forces during the surface contact experiments are also simulated. On average, the model was able to predict the steady-state pose of the finger with joint angle errors less than 6 deg across both free motion and surface contact experiments. The static contact forces were accurately predicted with an average of 11.5% force magnitude error and average direction error of 12 deg.
Measurements of the Flow in the Vicinity of an Additively Manufactured Turbine Leading-Edge Using X-Ray Particle Tracking Velocimetry
Authors: Ruiz Alex , Fezzaa Kamel , Kapat Jayanta , Bhattacharya Samik 
Published: November 2019

AbstractX-ray particle tracking velocimetry (PTV) is performed, for the first time, to measure the velocity field inside a leading-edge of a turbine blade made by laser-additive-manufacturing (LAM) process. The traditional showerhead holes were replaced by a porous matrix in the leading-edge. The flow through such a leading-edge piece cannot be faithfully recreated by traditional prototype testing methods due to the surface roughness and imperfections caused by LAM process. Hence, direct measurement is the only option. However, it is difficult to measure flow inside such pieces with traditional velocimetry measurements due to the existence of metallic walls. Moreover, small internal size and high flow speeds call for a measurement technique with high spatial and temporal resolutions. To address these issues, we performed time-resolved X-ray PTV using the Advanced Photon Source (APS) synchrotron facility at the Argonne National Laboratory (ANL). A hydraulic system was constructed to run water, mixed with seeding particles, through the leading-edge piece. A high-speed camera captured the images of the seeding particles, which were later processed to create particle tracks. The time-averaged velocity field showed distinct pairs of vortices located in front of the porous outlet inside the leading-edge piece. The inlet channel showed reversed flow due to partial obstruction by the porous inlet of the test piece. Such knowledge of the flow field inside a leading-edge of a turbine blade will help us to design better cooling paths leading to higher cooling efficiency and increased life-span of a turbine blade.
Improvements on Evaluation Functions of a Probabilistic Fracture Mechanics Analysis Code for Reactor Pressure Vessels
Authors: Lu Kai , Katsuyama Jinya , Li Yinsheng 
Published: November 2019

Abstract
In Japan, a probabilistic fracture mechanics (PFM) analysis code PASCAL was developed for structural integrity assessment of reactor pressure vessels (RPVs) considering neutron irradiation embrittlement and pressurized thermal shock (PTS) events. By reflecting the latest knowledge and findings, the evaluation functions are continuously improved and have been incorporated into PASCAL4 which is the most recent version of the PASCAL code. In this paper, the improvements made in PASCAL4 are explained in detail, such as the evaluation model of warm prestressing (WPS) effect, evaluation function of confidence levels for PFM analysis results by considering the epistemic and aleatory uncertainties in probabilistic variables, the recent stress intensity factor (KI) solutions, and improved methods for KI calculations when considering complicated stress distributions. Moreover, using PASCAL4, PFM analysis examples considering these improvements are presented.
High Amplitude Combustion Instabilities in an Annular Combustor Inducing Pressure Field Deformation and Flame Blow Off
Authors: Vignat Guillaume , Durox Daniel , Renaud Antoine , Candel Sébastien 
Published: November 2019

Abstract
This article reports experiments carried out in the laboratory scale annular combustor MICCA-spray equipped with multiple swirling spray injectors. The experimental setup consists in an air plenum connected to a combustion chamber formed by two concentric cylindrical quartz tubes, allowing full optical access to the flames. A new injection system is introduced and characterized. For a wide range of operating conditions, strong combustion instabilities are observed, but the focus of this article is placed on very high amplitude combustion instabilities coupled by a standing azimuthal mode. New results are obtained using a higher order reconstruction method for the pressure field: its shape is shown to be modified during high amplitude oscillation, leading to asymmetries of the pressure distribution in the system. Flame blow off occurs near the pressure nodal line when a critical level of oscillation is reached. A method is proposed to reconstruct the acoustic velocity field just before blow off occurs and in this way determine the blow off threshold. It is found that the pressure distribution, velocity field, and blow off pattern become asymmetric as the amplitude of oscillation increases and that this process is accompanied by a rapid shift in frequency of oscillation. Another notable result is that the heat release rate in the flames on the same side of the nodal line is not perfectly in phase and that the phase differences become larger as the amplitude of oscillation increases.
Comparison of Machine Learning Algorithms in the Interpolation and Extrapolation of Flame Describing Functions
Authors: McCartney Michael , Haeringer Matthias , Polifke Wolfgang 
Published: November 2019

Abstract
This paper examines and compares the commonly used machine learning algorithms in their performance in interpolation and extrapolation of flame describing function (FDFs), based on experimental and simulation data. Algorithm performance is evaluated by interpolating and extrapolating FDFs and then the impact of errors on the limit cycle amplitudes are evaluated using the extended FDF (xFDF) framework. The best algorithms in interpolation and extrapolation were found to be the widely used cubic spline interpolation, as well as the Gaussian processes (GPs) regressor. The data itself were found to be an important factor in defining the predictive performance of a model; therefore, a method of optimally selecting data points at test time using Gaussian processes was demonstrated. The aim of this is to allow a minimal amount of data points to be collected while still providing enough information to model the FDF accurately. The extrapolation performance was shown to decay very quickly with distance from the domain and so emphasis should be put on selecting measurement points in order to expand the covered domain. Gaussian processes also give an indication of confidence on its predictions and are used to carry out uncertainty quantification, in order to understand model sensitivities. This was demonstrated through application to the xFDF framework.
Provenance of Eocene–Oligocene sediments in the San Jacinto Fold Belt: Paleogeographic and geodynamic implications for the northern Andes and the southern Caribbean
Authors: Osorio-Granada E. , Pardo-Trujillo A. , Restrepo-Moreno S.A. , Gallego F. , Muñoz J. , Plata A. , Trejos-Tamayo R. , Vallejo F. , Barbosa-Espitia A. , Cardona-Sánchez F.J. , Foster D.A. , Kamenov G. 
Published: November 2019

AbstractMesozoic and Cenozoic strata of the San Jacinto Fold Belt (Colombian Caribbean) provide insights about sedimentary environments and paleogeographic evolution in the transition between the northern Andes and the South Caribbean deformed belt. We report new provenance (conventional sandstone petrography, heavy mineral analysis, and detrital zircon U-Pb geochronology and typology) and micropaleontologic data (palynology, calcareous nannofossils, and foraminifera) in samples collected from the lower Eocene (San Cayetano Formation) and upper Eocene–Oligocene (Toluviejo and Ciénaga de Oro Formations) rocks in boreholes drilled by the Colombian Agencia Nacional de Hidrocarburos as well as from recently exposed Oligocene outcrops from the Ciénaga de Oro Formation. Sandstone petrography shows modal variations, with high feldspar content in the lower Eocene rocks and high quartz content in the Oligocene deposits. This shift in compositional maturity may be due to climatic variations, tectonic activity, and/or changes in source areas. Heavy mineral analyses indicate variations that suggest sources primarily related to felsic igneous and/or low-grade metamorphic and mafic and ultramafic rocks. Zircon U-Pb geochronology displays age populations mainly in the Late Cretaceous, Late Jurassic, Permian–Triassic, and Precambrian (ca. 900–1500 Ma). In addition, zircon typology analyses indicate that the igneous zircons came primarily from monzogranites and granodiorites. Finally, the micropaleontologic and sedimentary data sets indicate that the sediments were deposited in tropical coastal and shallow marine environments. The sediments were transported by short rivers from the crystalline massifs of the Lower Magdalena Valley and the northern Central Cordillera basements, while distal transport of sediments may have occurred along longer rivers, which brought sediments from southern regions located between the Central and Western Cordilleras.
Evaluation of community coalition training effects on youth hospital-admitted injury incidence in Victoria, Australia: 2001–2017
Authors: Berecki-Gisolf Janneke , Rowland Bosco , Reavley Nicola , Minuzzo Barbara , Toumbourou John 
Published: November 2019

BackgroundInjuries are one of the three leading causes of morbidity and mortality for young people internationally. Although community risk factors are modifiable causes of youth injury, there has been limited evaluation of community interventions. Communities That Care (CTC) offers a coalition training process to increase evidence-based practices that reduce youth injury risk factors.MethodUsing a non-experimental design, this study made use of population-based hospital admissions data to evaluate the impact on injuries for 15 communities that implemented CTC between 2001 and 2017 in Victoria, Australia. Negative binomial regression models evaluated trends in injury admissions (all, unintentional and transport), comparing CTC and non-CTC communities across different age groups.ResultsStatistically significant relative reductions in all hospital injury admissions in 0–4 year olds were associated with communities completing the CTC process and in 0–19 year olds when communities began their second cycle of CTC. When analysed by subgroup, a similar pattern was observed with unintentional injuries but not with transport injuries.ConclusionThe findings support CTC coalition training as an intervention strategy for preventing youth hospital injury admissions. However, future studies should consider stronger research designs, confirm findings in different community contexts, use other data sources and evaluate intervention mechanisms.
Osler Centenary Papers: William Osler in medical education
Authors: Leach Helen , Coleman Jamie J 
Published: November 2019

AbstractWilliam Osler combined many excellent characteristics of a clinical educator being a scientific scholar, a motivational speaker and writer and a proficient physician. As we celebrate his life a century on, many of his educational ideals are as pertinent today as they were in those Victorian times. Osler’s contributions to modern medicine go beyond his legacy of quotable aphorisms to a doctor, educator and leader whose proponent use of bedside teaching, careful clinical methods, and clinicopathological correlation was a great inspiration for students and junior doctors. He was also a great advocate of patient-centred care—listening to and closely observing his patients, an important message for modern medicine as the reliance on investigations strains modern healthcare systems. This review of Osler’s contribution to medical education summarises his development as an educator and provides reflection on his influences to modern clinical education.
Osler Centenary Papers: Management of pleural infection: Osler’s final illness and recent advances
Authors: Gregory Prudence , Rahman Najib M , Lee Y C Gary 
Published: November 2019

AbstractSir William Osler’s great work and achievements are extensively documented. Less well known is his prolonged battle with postinfluenza pneumonia, lung abscess and pleural infection that eventually led to his demise. At the age of 70, he was a victim of the global Spanish influenza epidemic, and subsequently developed pneumonia. In the era before antibiotics, he received supportive care and opium for symptom control. The infection extended to the pleura and he required repeated thoracentesis which failed to halt his deterioration. He proceeded to open surgical drainage involving rib resection. Unfortunately, he died shortly after the operation from massive pleuropulmonary haemorrhage. In this article, we review the events leading up to Osler’s death and contrast his care 100 years ago with contemporary state-of-the-art management in pleural infection.
Osler Centenary Papers: Osler, inscribed
Authors: Hague-Yearl Mary K K 
Published: November 2019

AbstractBackgroundAs the centenary of Sir William Osler’s death approaches on 29 December 2019, it is worth pausing to reflect on the relationship between the Osler Library of the History of Medicine at McGill University and the image of William Osler, for the two are arguably inextricable. When Osler died he had not yet completed his library, yet his donation to McGill included nearly 8000 volumes that represented the foundations of western medicine. The Osler Library now boasts over 100 000 titles and is recognised globally as a centre for the study of medical history.MethodsThe approach taken here was to examine inscriptions in the books that William Osler bequeathed to the McGill Medical Facultyin order to learn more about William Osler, the man.ResultsBy examining inscriptions William Osler and others made in his books, it was possible to learn more about how Osler interacted with his friends, his patients, and also his books.ConclusionIt is argued that these inscriptions are as instructive as they are enriching. They reveal information about Osler’s priorities and his personal and professional relationships; future scholars will likely find it useful to examine inscriptions more broadly, to gain insight into such topics as the book trade and world events.
4 Advances in palliative care
Authors: Taylor Ros 
Published: November 2019

Abstract
Palliative care is at a pivotal point in its trajectory. For the last 50 years there has been a focus on service development for the new specialty, the safer use of opioids and obtaining the evidence that palliative care makes a difference, the earlier the better.
However the next 50 years will be a massive challenge, but also an opportunity. There will be a shortage of all physicians, not just palliative physicians and this is a perfect storm with our increased longevity, frailty and comorbidities.
The lecture will focus on potential solutions, drawing on global innovation and imagination. Having braver conversations about the future is all very well but we also need practical options to improve the care of dying people in all settings not just five-star hospices, and we need to be less risk-averse about supporting patient and family goals of care in a culture dominated by compliance rather than comfort and care!