bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Quantitative Study on the Influence of Operating Parameters Upon Thermal Performance of Heating Furnace
Authors: Huang Haogang , Zheng Zhiguang , Yao Jian , Zhang Lin , Bu Shi , Xu Fang , Xu Weigang , Ding Hong 
Published: September 2022

Abstract
With the development of the social economy, people’s demand for energy is increasing. As a kind of high energy consumption equipment in petrochemical enterprises, the heating furnace is imperative to reduce its energy consumption. Therefore, in order to further improve the thermal efficiency of the heating furnace and reduce the emission of pollutants, this paper combines the actual operation of the SRT-III heating furnace in the chemical plant to establish a fluid domain model. The effects of different values of excess air coefficient, air preheating temperature, and oxygen concentration on the flow field characteristics and furnace thermal efficiency under two kinds of blackness were analyzed by numerical simulation. The results show that higher blackness has higher furnace thermal efficiency. Under the conditions of a balance between thermal efficiency and environmental protection performance, the optimal values of excess air coefficient, air preheating temperature, and oxygen concentration are 1.20, 473 K, and 25%, respectively.
Unsteady Structure of Compressor Tip Leakage Flows
Authors: Maynard Joshua M. , Wheeler Andrew P. S. , Taylor James V. , Wells Roger 
Published: September 2022

Abstract
Direct numerical simulations (DNS) are performed of a cantilevered stator blade to identify the unsteady and turbulent flow structure within compressor tip flows. The simulations were performed with clearances of 1.6% and 3.2% of chord. The results show that the flow both within the gap and at the exit on the suction side highly unsteady phenomena controlled by fine-scale turbulent structures. The signature of the classical tip-leakage vortex is a consequence of time-averaging and does not exist in the true unsteady flow. Despite the complexity, we are able to replicate the flow within the tip gap using a validated quasi-three-dimensional (Q3D) model. This enables a wide range of Q3D DNS simulations to study the effects of blade tip corner radius and Reynolds number. Tip corner radius is found to radically alter the unsteady flow in the tip; it affects both separation bubble size and shape, as well as transition mechanisms in the tip flow. These effects can lead to variations in tip mass flow of up to 10% and a factor of 2 variation in dissipation within the tip gap.
Development of a Numerical Model to Assess Sensitivity for Fiber Probe Frequency-Domain Thermoreflectance Measurements
Authors: Warzoha Ronald J. 
Published: September 2022

Abstract
Theremoreflectance techniques that utilize a fiber-based probe have obvious advantages for characterizing the thermal properties of liquids and biological materials. For instance, an all-fiber thermoreflectance system would allow for its integration into advanced microscope facilities to characterize the local thermal properties of biological materials. However, it is unclear to what extent the probe itself is sensitive to material thermal properties, particularly as the thermal conductance between the transducer and the contacting material is changed by orders of magnitude. The impacts of the transducer’s thermal properties, the fiber’s mode field diameter, and fiber cladding thickness on measurement sensitivity are also not well understood. In this paper, I develop a numerical model to evaluate the sensitivity of a fiber-based thermoreflectance probe when used to characterize the thermal properties of materials with Frequency-domain thermoreflectance (FDTR).
A Numerical Study on Sweeping Mist Jet Impingement Cooling
Authors: Wang Ting , Abdelmaksoud Ramy 
Published: September 2022

Abstract
This paper presents a 2-D numerical study to investigate the fluid flow behavior and cooling characteristics caused by injecting tiny droplets into the sweeping air jet through a fluidic oscillator. An unsteady Reynolds-averaged Navier-Stokes (URANS) simulation accompanied with the k-ω SST turbulence model is used in this study. The movement and evaporation of the mist are simulated by using the discrete phase model (DPM). The study has been conducted for a target wall with a constant heat flux of 3,000 W/m2, jet-to-wall distance of 4, ReD = 2,500, and a mist /air mass ratio of 5% with a droplet size of 5 microns. A comparison between the cooling performance of steady and sweeping jets is presented for two impingement schemes (i.e., confined and unconfined impingement). The approach of using a slip upper wall boundary condition as an alternative of the unconfined impingement scheme is investigated as well. The results show that adding mist provided a temperature reduction of 5–10% on the target wall in all cases when compared to the air cases. Mist mostly follows the air jet behavior in both steady and sweeping jets in both impingement schemes. The liquid droplet coalescence phenomenon prevails in the sweeping jet case, while it is not as significant in the steady jet case. For the confined impingement, both mist jets provided the similar average temperature reduction. However, the steady mist jet introduced a 58% more target wall shear compared to the sweeping mist jet. For the unconfined impingement, the steady mist jet achieved a better average cooling performance compared to that of the sweeping mist jet. However, the steady mist jet introduced a 72% more target wall shear compared to the sweeping mist jet. Using a slip upper wall boundary condition to reduce the computational time resulted in similar average heat transfer distribution on the target wall to the unconfined case. However, the flow pattern, vortical structures, and droplet dynamics were very different.
Uncertainty Analysis of Vapor Transport Measurement in a Hollow Fiber Membrane Module for Membrane Humidifier
Authors: Nguyen Xuan Linh , Yu Sangseok 
Published: September 2022

Abstract
Moisture is a crucial factor in the durability and performance of proton exchange membrane fuel cells, frequently managed with external humidification of reactant gases. Membrane humidifiers have been utilized to maintain proper water content levels of cathode air in vehicular fuel cell systems, avoiding fuel cell operation limits, especially in high temperature conditions.
Since the precise measurement of hollow fiber membrane performance ensures the design capability of the shell-tube membrane humidifier, it is necessary to understand the measurement uncertainty of vapor transport through the hollow fiber membrane. In this study, the uncertainty of the water vapor transport rate is analyzed with experimental data. Parametric investigation of vapor transport was carried out with isothermal conditions and variation of operating parameters including temperature, pressure, and inlet relative humidity. The vapor transport is presented by the vapor transfer rate from the wet air to the dry air through the membrane, which is affected by the sensitivity of the foregoing operating parameters and the reliability of sensors. The reliable data of humidifier performance is of vital importance in fuel cell system optimization. Therefore, the uncertainty analysis of individual parameters and the vapor transfer rate was conducted to confirm the reliability of vapor transport experiments.
A Review on Film Cooling Research: Historical Developments in Hole Shapes, Measurement Techniques, Effects of Operating Conditions, and Impact of Additive Manufacturing
Authors: Kaur Inderjot , Dutta Sandip , Singh Prashant 
Published: September 2022

Abstract
Film cooling is a widely adopted technology in high pressure stages of gas turbines in both propulsion and power-generation areas to keep the turbine components in the safe operation range. This cooling concept was first introduced by Prof. Goldstein’s group from University of Minnesota in 1970s. Much of the follow up research efforts have been focused on the film hole shapes, measurement techniques, and film cooling performance under various mainstream and coolant side operating conditions. Here, a comprehensive developmental review from mid 2000s is presented to summarize the technical improvements and future path. Due to recent rapid advancements in the areas of measurement techniques (e.g., Pressure sensitive paints) and metal additive manufacturing, the film cooling technology has undergone significant changes. This article provides a historical perspective with over five decades of innovations in the area, and the effects of injection angle, hole shape, density ratio, momentum-flux ratio, blowing ratio, advective capacity ratio, and freestream conditions, etc. The impact of additive manufacturing on the film hole design strategies, current challenges posed by state-of-the-art AM technology, and pathways for future research is then discussed thoroughly. Detailed discussion is provided on the AM print quality in terms of dimensional accuracy, surface roughness and its subsequent effect on the adiabatic film cooling effectiveness and net heat flux reduction. A comparative study is performed with the AM assisted film hole fabrication and conventionally manufactured film holes.
Heat Transfer on Fuel Injector Surface With Backward Facing Stepped Scramjet Flame Holder
Authors: Bae Hyung Mo , Kim Jihyuk , Nam Juyeong , Chang Injoong , Moon Hee Koo , Cho Hyung Hee 
Published: September 2022

Abstract
The scramjet engine burns fuel under supersonic flow condition in a combustion chamber while minimizing total pressure such that it can operate under both supersonic and hypersonic flows. For combustion under supersonic flow field, a flame holder is essential to overcome short fuel residence time and poor mixing, and a backward facing step is the simplest and best performing method that can be used as a flame holder. Proper interaction between the flame holder and fuel injection can improve engine performance in fluidic conditions. However, it creates significantly more heating condition that imposes challenges in thermal design and thermal management. In the flame holder design, measuring and analyzing the flow mixing and heat transfer characteristics should be preceded. In this study, flow mixing and heat transfer characteristics analysis by flame holder and secondary injection were performed by numerical simulations. In a flow field with Mach 3 mainstream, the test domain in which a 5 mm backward facing step and a hole for fuel injection in the downstream area was selected for experiment. The sonic jet is generated in the circular hole. First, to analyze the effect of the backward facing step on the secondary injection and supersonic crossflow, heat transfer and comparative analyses were performed with and without the backward facing step. And the effect of the ratio between hole position and step height on the heat transfer was analyzed. Two approaches were used to analyze the heat transfer. One was to analyze the point where the transfer phenomenon increased, and the second was to analyze how much the area affected as the heat transfer increased. As the position of the hole on the step raised, the resulting heat transfer increased, but the area size affected by this high heat transfer decreased and then increased again.
Spatiotemporally heterogeneous deformation, indirect tectonomagmatic links, and lithospheric evolution during orogenic activity coeval with an arc flare-up
Authors: Attia Snir , Paterson Scott R. , Jiang Dazhi , Miller Robert B. 
Published: September 2022

Abstract
Broad overlap between deformation and magmatism in active margins has spurred the development of a conceptual framework of direct tectonomagmatic links in both active and ancient arcs. Although widespread and highly influential, such models have only rarely been critically evaluated. Rigorously linking tectonism, geodynamics, lithospheric evolution, and arc activity requires detailed reconstructions of the spatiotemporal patterns of magmatism and deformation across both a sufficiently wide area and a range of observational scales. Herein, new constraints on the timing, extent, and characteristics of deformation during mid-Cretaceous tectonism in the central Sierra Nevada (eastern California, USA) are synthesized with published geologic mapping, structural studies, and geochronology to create an updated reconstruction of one of the type examples of a hot, magma-rich orogen. Tilted strata, tectonic fabrics, and shear zones with variable geometries, kinematics, intensity, and timing reveal a significantly revised record of ~25 m.y. of heterogeneous deformation ca. 105–80 Ma. Deformation and magmatism show distinct and unrelated spatiotemporal patterns throughout this orogenic episode. Contrary to previous models of direct tectonomagmatic links, many of which were developed in the central Sierra Nevada, arc activity did not control the location, intensity, or kinematics of intra-arc deformation, nor did shear zones control the location of magmatism. Furthermore, arc lithosphere appears to have strengthened, rather than weakened, as the arc-orogenic flare-up proceeded. In addition to changing plate-scale boundary conditions, lithospheric-scale rheological evolution likely played a key role in the patterns of Late Cretaceous deformation observed across strike of the entire Cordilleran margin.
The effects of pre-stress assumptions on dynamic rupture with complex fault geometry in the San Gorgonio Pass, California, region
Authors: Tarnowski Jennifer M. , Kyriakopoulos Christodoulos , Oglesby David D. , Cooke Michele L. , Stern Aviel 
Published: September 2022

Abstract
We use three-dimensional (3-D) dynamic finite-element models to investigate potential rupture paths of earthquakes propagating along faults through the western San Gorgonio Pass, a structurally complex region along the San Andreas fault system in southern California (USA). We focus on the right-lateral San Bernardino strand of the San Andreas fault system, the oblique thrust–right-lateral San Gorgonio Pass fault zone, and a portion of the right-lateral Garnet Hill strand of the San Andreas fault system. We use the 3-D finite-element method to model rupture propagation along a fault geometry that reflects current understanding of the local geometrical complexity and is consistent with long-term loading and observed surface deformation. We test three different types of pre-stress assumptions: (1) constant tractions (assuming pure right-lateral strike-slip motion on the San Bernardino and Garnet Hill strands and oblique thrust–right-lateral strike-slip motion on the San Gorgonio Pass fault zone), (2) a uniform regional stress regime, and (3) long-term (evolved) stress from quasi-static crustal deformation modeling. Our results imply that under the more realistic regional stress and evolved stress assumptions, throughgoing rupture propagation from the southeast to northwest (i.e., from the Garnet Hill to the San Bernardino strand) may be more likely than throughgoing rupture in the reverse direction (from the San Bernardino to the Garnet Hill strand). The results may have implications for the earthquake potential in the region as well as for ground motion in the Los Angeles Basin. The results also emphasize how fault geometry and stress patterns combine to influence rupture propagation on complex fault systems.
Determination of the Heating Rate and Temperature of an Ion Chain in a Linear Paul Trap by the Dephasing of Rabi Oscillations
Authors: Semenin N. V. , Borisenko A. S. , Zalivako I. V. , Semerikov I. A. , Aksenov M. D. , Khabarova K. Yu. , Kolachevsky N. N. 
Published: September 2022

The optimization of the parameters of laser cooling and the investigation of the heating rate in ion traps require the measurement of the temperature of ion chains for which the Lamb–Dicke regime is satisfied. A novel method based on the investigation of the dynamics of Rabi oscillations at a narrow electron transition in an individual ion of the chain has been suggested for such measurement. An analytical expression for the population of the upper state as a function of the excitation time is derived taking into account the thermal distribution of phonons over the vibrational modes of a chain with an arbitrary number of ions. The method is tested experimentally for the chain of five $$^{{171}}{\text{Y}}{{{\text{b}}}^{ + }}$$ ions using the quadrupole transition at 435 nm, as well as for a single ion. The heating rate measured for the axial vibrational mode in the implemented trap is 8 × 103 phonons/s.
Evolution of the Reaction Front Shape and Structure on Flame Acceleration and Deflagration-to-Detonation Transition
Authors: Krivosheyev P. N. , Novitski A. O. , Penyazkov O. G. 
Published: September 2022

Abstract
Flame acceleration (FA) and the deflagration-to-detonation transition (DDT) are among the most interesting and exciting phenomena in the field of combustion and explosion of gases. From both practical and theoretical points of view, it is important to understand the basic laws governing these phenomena as well as the physical and/or chemical mechanisms and features of the process. High-speed flame-front photography during the deflagration of a premixed gas mixture in a long smooth tube with transparent walls was performed. A stoichiometric mixture of acetylene with oxygen diluted with argon by 25% is used. The experiments are carried out in a transparent cylindrical tube with an inner diameter of 60 mm and a length of 6 meters. The evolution of the structure and shape of the flame front from the moment of initiation of deflagration by a weak ignition source to the formation of a detonation wave is determined. Four characteristic phases of the propagation process are distinguished: at the first stage, the flame accelerates, then slows down, followed by flame propagation at an almost constant speed, and finally repeated acceleration, during which detonation is formed. It is shown how the dynamics of the process changes with a change in the initial pressure of the mixture. The most interesting and poorly studied stage of the DDT, the stage of intensive reacceleration, during which the flame abruptly changes shape, is described in detail.
Improving epinephrine autoinjector usability and carriage frequency among patients at risk of anaphylaxis: a quality improvement initiative
Authors: Ziyar Ahdad , Kwon Jimmy , Li Arthur , Naderi Asal , Jean Tiffany 
Published: September 2022

Although epinephrine autoinjectors (EAIs) are crucial for the management of anaphylaxis, patient carriage frequency of EAI is as low as 57% and usage of EAIs is erroneous 35%–43% of the time. Our objective was to improve patient carrying frequency of EAI and understanding of EAI usage.We implemented a quality improvement initiative using consistent closed-loop education, redesigned clinic workflow, electronic medical record reminder-based interventions, and educational materials to improve patient EAI carriage compliance and understanding of EAI indications and proper technique.The percentage of our patients who carried the EAI at all times increased from 55% to 93% in 6 months. Participants knowledge of EAI indications also improved from 22% to 91%. Patient demonstration scores of the EAI device improved from 21% to 91% as well.Our quality improvement interventions demonstrated a significant improvement>80% in EAI carriage frequency, knowledge of indications, and proper device technique.
Barrett’s oesophagus with indefinite for dysplasia shows high rates of prevalent and incident neoplasia in a UK multicentre cohort
Authors: Kopczynska Maja , Ratcliffe Elizabeth , Yalamanchili Harika , Thompson Anna , Nimri Adib , Britton James , Ang Yeng 
Published: September 2022

AimsBarrett’s oesophagus with indefinite for dysplasia (IDD) carries a risk of prevalent and incident dysplasia and oesophageal adenocarcinoma. This study seeks to determine the risk of neoplasia in a multicentre prospective IDD cohort, along with determining adherence to British Society of Gastroenterology (BSG) guidelines for management and histology reporting.MethodsThis was a cohort study using prospectively collected data from pathology databases from two centres in the North West of England (UK). Cases with IDD were identified over a 10-year period. Data were obtained on patient demographics, Barrett’s endoscopy findings and histology, outcomes and histological reporting.Results102 biopsies with IDD diagnosis in 88 patients were identified. Endoscopy was repeated in 78/88 (88%) patients. 12/78 progressed to low-grade dysplasia (15% or 2.6 per 100 person years), 6/78 (7.7%, 1.3 per 100 person years) progressed to high-grade dysplasia and 6/78 (7.7%, 1.3 per 100 person years) progressed to oesophageal adenocarcinoma. The overall incidence rate for progression to any type of dysplasia was 5.1 per 100 person years. Cox regression analysis identified longer Barrett’s segment, multifocal and persistent IDD as predictors of progression to dysplasia. Histology reporting did not meet 100% adherence to the BSG histology reporting minimum dataset prior to or after the introduction of the guidelines.ConclusionsIDD carries significant risk of progression to dysplasia or neoplasia. Therefore, careful diagnosis and management aided by clear histological reporting of these cases is required to diagnose prevalent and incident neoplasia.
Impact of atrial fibrillation on the risk of major adverse cardiac events following coronary revascularisation
Authors: Jung Richard G , Abdel-Razek Omar , Di Santo Pietro , Gillmore Taylor , Stotts Cameron , Makwana Dwipen , Soriano Joelle , Moreland Robert , Verreault-Julien Louis , Goh Cheng Yee , Parlow Simon , Sypkes Caleb , Ramirez Daniel F , Sadek Mouhannad , Chan Vincent , Toeg Hadi , Simard Trevor , Froeschl Michael P V , Labinaz Marino , Hibbert Benjamin 
Published: September 2022

ObjectiveAtrial fibrillation (AF) remains a highly prevalent arrhythmia with significant burden on morbidity and mortality. The impact of AF in the revascularised population remains incompletely described. Given the high prevalence of AF in the revascularised population, we sought to evaluate the incidence and prognosis in patients with pre-existing and new-onset AF following revascularisation.MethodsWe used the University of Ottawa Heart Institute Revascularisation Registry to identify patients who underwent revascularisation between August 2015 and March 2020, who were prospectively followed for an average of one year. We conducted a retrospective cohort study analysing the association between AF and clinical outcomes. The primary outcome of interest was 1-year major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, unplanned revascularisation and cerebrovascular accidents. Moreover, secondary outcomes include the individual components of MACE and bleeding.ResultsA total of 6704 patients underwent revascularisation and completed 1-year clinical follow-up. Median time to follow-up was 12.8 (IQR 11.2–15.9) months. One-year MACE occurred in 166 (21.8%) and 683 (11.5%) patients in AF and non-AF groups, respectively (adjusted HR, 1.61; 95% CI 1.29 to 2.01; p<0.0001). AF was independently predictive of 1-year mortality, myocardial infarction, unplanned revascularisation, cerebrovascular accident and bleeding. Within 1 year, 299 (4.5%) episodes of new-onset AF was observed. New-onset AF following revascularisation was also associated with 1-year MACE, mortality, myocardial infarction, cerebrovascular accident and unplanned revascularisation.ConclusionsPreprocedural and new-onset AF following revascularisation remains highly predictive 1-year MACE. AF should be considered in addition to traditional risk factors for adverse outcomes following revascularisation.