bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Numerical Evaluation of a Simple Procedure for Using Transient Surface Temperature Measurements to Determine Local Convective Heat Transfer Rates
Authors: Oosthuizen Patrick H. , Naylor David 
Published: December 2021

Abstract
A transient method, based on an inverse heat conduction solution, for experimentally determining the distribution of local heat transfer rates on the surface of a body has been numerically evaluated. The particular interest is in situations in which the heat transfer coefficients are relatively low and in which there are relatively large changes in the heat transfer coefficient over the surface of the body being considered. In the method, a solid body of the shape being investigated, constructed from a low conductivity material, is heated to a uniform temperature and then exposed to a test flow. Using a layer of temperature sensitive crystal placed over the surface of this model or by other means, the time taken for the temperature at a relatively small number of selected points on the surface to reach a selected value is determined. The surface heat flux rate distribution is then found from these measured times using a simple inverse heat conduction method. The feasibility of this method has been evaluated by considering relatively low Reynolds number flow over a square cylinder and natural convective flow over a circular cylinder. Known local heat transfer coefficient distributions for these situation have been applied as boundary conditions in the numerical solution of the transient cooling of a the “experimental” models. These solutions are used to generate “measured” data i.e. to generate simulated experimental data. The inverse heat transfer method has then been used to predict the local heat transfer coefficient distribution over the surface and the predicted and input distributions have been compared. The effect of uncertainties in the experimental measurements on this comparison has then been evaluated using various assumed uncertainty values. The results of the study indicate that the proposed method of measuring local heat transfer coefficients is capable of giving results of good accuracy.
Heat Flux: A Design, Diagnostic and Control Parameter for Thermal Equipment
Authors: Martins N. , Afgan N. H. , Carvalho M. G. , Nogueira M. 
Published: December 2021

Abstract
Heat flux is a space and time variable reflecting the state of a thermal system. The evaluation of heat flux properties in thermal systems gives the possibility of making an assessment of their efficiency, safety and availability. In this respect, it was proved that heat flux is an important design, diagnostic and control parameter for many thermal systems.
This paper describes the evaluation of different aspects of heat flux properties including heat flux as a design parameter, heat flux as a diagnostic parameter and heat flux as a control parameter.
The heat flux is proved to reflect the changes in thermal equipment during operation. The malfunction of this equipment is closely related to the change of the heat flux distribution within the system. In this respect, it was demonstrated that the failure of boilers and furnace operation could be diagnosed by the change in the heat flux distribution on the respective heat transfer surfaces. The heat flux, as a diagnostic variable for the assessment of the operation of thermal systems, will open a challenging opportunity for the design of on-line knowledge-based systems. This can be used for the assessment of efficiency and safety of thermal systems.
A new method for heat flux measurement is introduced with reference to its use in boiler and glass furnaces. It shows the advantages of the new method when applied in high temperature and hostile environments.
Reduction of Fire Hazards Downwind of Wind-Driven Fires by Tree Barriers: Part IV — Numerical Simulation of Real-Scale Fires Located in Kobe City, Japan
Authors: Satoh K. , Yoshihara H. , Sagae K. , Naba H. , Araiba K. , Yang K. T. 
Published: December 2021

Abstract
Earlier laboratory studies were carried out to determine the effectiveness of implementing the use of tree barriers to protect open areas such as parks and schoolyards from large wind-driven urban fires. Numerical simulations based on a field fire model also produced promising results which corresponded well with the laboratory experimental observations and measurement data The confidence gained in these earlier studies has led to the present study to simulate the implementation of various tree-barrier configurations in an actual park in Kobe City, Japan under real-scale fire and prevailing wind conditions similar to those encountered in the 1995 Great Kobe Earthquake. Among the various barrier configurations studied, it has been demonstrated that the best configuration is the one using a dual barrier system to reduce the temperatures in the open park downwind from the barriers to safe levels.
Numerical Modeling of Turbulent Heat Transfer and Fluid Flow in a Tunnel Pasteurization Process
Authors: Zheng Y. H. , Amano R. S. 
Published: December 2021

Abstract
The purpose of this study is to model the heat transfer and fluid flow in a tunnel pasteurizer, which can be used to predict the operation status of the pasteurization process. This modeling is very useful when some changes must be made to the design, operation, or the types of products to be pasteurized. Moreover, the model can be used to provide valuable data for the optimization of the pasteurization design.
In the modeling two approaches have been adopted. One is the Lumped Parameter Method (LPM), which is used to model the whole pasteurization system, including pipes, zones and heat exchangers. The other one is the Computational Fluid Dynamics (CFD) technology for calculations of the heat transfer and fluid flow rates in the heat exchanger tank. A steady state model in a tunnel pasteurizer has been developed by using the LPM. The temperatures of the spray water and the products in the pasteurization process were calculated by employing this model. The comparisons showed reasonably good agreements between the predicted results and the experimental data. The pressure variations along the regenerative loops were also calculated. With the CFD technology, the numerical calculations of heat transfer and fluid flow have been performed on the temperature distribution in the cylindrical heat exchanger tank that provides a hot water through the top and a cold water through the bottom of tank. There are two outlets. In the heat exchanger tank, the tube arrays are set along the azimuth direction of the tank. This is a thermally stratified layered water tank that can control the four zones of the water temperatures.
Pool Boiling Heat Transfer From Plain and Microporous, Square Pin Finned Surfaces in Saturated FC-72
Authors: Rainey K. N. , You S. M. 
Published: December 2021

Abstract
The present research is an experimental study of “double enhancement” behavior in pool boiling from heater surfaces simulating microelectronic devices immersed in saturated FC-72 at atmospheric pressure. The term “double enhancement” refers to the combination of two different enhancement techniques: a large-scale area enhancement (square pin fin array) and a small-scale surface enhancement (microporous coating). Fin lengths were varied from 0 (flat surface) to 8 mm. Effects of this double enhancement technique on critical heat flux (CHF) and nucleate boiling heat transfer in the horizontal orientation (fins are vertical) are investigated. Results showed significant increases in nucleate boiling heat transfer coefficients with the application of the microporous coating to the heater surfaces. CHF was found to be relatively insensitive to surface microstructure for the finned surfaces except in the case of the surface with 8 mm long fins. The nucleate boiling and CHF behavior has been found to be the result of multiple, counteracting mechanisms: surface area enhancement, fin efficiency, surface microstructure (active nucleation site density), vapor bubble departure resistance, and re-wetting liquid flow resistance.
Investigation of the Real Process Data on Basis of Closed Mass- and Energy Balances in Nuclear Power Plants (NPPs)
Authors: Grauf E. , Jansky J. , Langenstein M. 
Published: December 2021

Abstract
This contribution presents an overall mathematical survey of the nuclear power plant (NPP) process in terms of functional redundancy in relation to performance measurements and reactor output calculations.
With the help of VALI software it has been possible to verify significant differences in the average coolant temperature (CT) values compared with the displayed values, in particular in respect of starting up the plant. Corrections in the operating mode, which were made on the basis of the validation data, have resulted in maximum output being achieved more quickly.
By tracking the trends of the component output data calculated from validated data, it has been possible to obtain direct indications of weaknesses in the process engineering. With the help of an examination of sensitivity, an incorrect measuring chain response can be identified. For this purpose, automatically generated report forms are produced and these are used to maintain the measuring chains.
The replacement of equipment calibration by functional redundancy in relation to the measured performance values results in potential savings in respect of maintenance activities such as recurrent tests (RT) and recurrent maintenance measures (RM) of approx. DM 1.1 million per LWR unit/year.
Safety Engineering for the Relativistic Heavy Ion Collider at the Brookhaven National Laboratory
Authors: Musolino Stephen V. , Kane Steven F. , Levesque Joseph W. 
Published: December 2021

Abstract
The Relativistic Heavy Ion Collider (RHIC) is a high energy particle accelerator built to study basic nuclear physics. It consists of two counter-rotating beams of fully stripped gold ions that are accelerated in two rings to an energy of 100 GeV/nucleon. The rings consist of a circular lattice of superconducting magnets, 3.8 km in circumference. The beams can be stored for a period of five to ten hours and brought into collision for experiments during that time. The first major physics objective when the facility goes into operation is to recreate a state of matter, the quark-gluon plasma, that has been predicted to have existed at a short time after the creation of the universe. There are only a few other high energy particle accelerators like RHIC in the world. Each one is unique in design and contains systems and hazards that are not commonly found in general industry. Therefore, the designers of the machine do not always have consensus design standards and regulatory guidance available to establish the engineering parameters for safety. Some of the areas where standards are not available relate to the cryogenic system, containment of large volumes of flammable gas in fragile vessels in the experimental apparatus and mitigation of a Design Basis Accident with a stored particle beam. The ASME Code requires Charpy testing of welds at cryogenic temperature, but testing at 4 K is nearly impossible to conduct. Engineered welds were used to provide an equivalent level of safety. A cryogenic system is a process system. The RHIC system was designed first by selecting a safe operating mode, then analyzing to ensure this mode was preserved. Cryogenic systems have unique processes, and the safe mode will surprise most process engineers. The experimentalists require detectors to be designed to meet the need of the physics objectives, but the application of standard construction techniques would make research mission impossible. Unique but equivalent safety engineering must be determined. The rules promulgated in the Code of Federal Regulations under the Atomic Energy Act do not cover prompt radiation from accelerators, nor are there any State regulations that govern the design and operation of a large superconducting collider. Special design criteria for prompt radiation were developed to provide guidance for the design of radiation shielding.
Stress Analysis of Stainless Steel Elbow and Tee Fittings Subjected to Internal Pressure and External Loads
Authors: Sawa Toshiyuki , Furuya Tetsuya , Murakami Tadahiro , Kagaya Yasuyuki 
Published: December 2021

Abstract
In this paper, mechanical behaviors of the Elbow and Tee fittings connected to pipes by screw threads under internal pressure, external tensile loads and bending moment are analyzed using the Finite Element Method (FEM). FEM code employed is MARC. The maximum Mises stress of the Elbow and Tee fittings are obtained when the wall thickness is changed while the internal working maximum pressure is held constant at 20bar. The elasto-plastic stress states of screw threads the fittings and the pipes are obtained under internal pressure and external loads. Under the assumptions that nodal points are released when the strain of the elements reaches the rupture strain of the fitting’s material, the load when the rupture occurs at the screw thread is analyzed. The safety factor for the wall thickness of the Elbow and Tee fittings used in the experiment is found to be about 5. The results indicate deduced that the dimensions of Elbow and Tee fittings can be reduced. The strength of the fittings under internal pressure and external loads is obtained. It is found that the stress concentrates at the first root of male thread and expected that a fracture initiates at the first root. The strain of the Elbow and Tee fittings subjected to internal pressure were measured by using strain gauges. The numerical results are in a fairly good agreement with the experimental results.
Short Carbon Fibers Composites With High Filler Contents Rheology and Mechanical Properties
Authors: Schmitt Y. , Paulick C. , Bour Y. , Royer F. X. 
Published: December 2021

Abstract
The control of the quality of mixture based on very short carbon fibers and epoxyde resins leads to suitable mixture for molding of complex geometries. A gain in fluidity is obtained if the suspensions are treated by ultrasounds and simultaneously stirred under vacuum. Addition in a very small ratio of microbubbles in the mixture allows to obtain a viscosity less than those of the matrix alone. For many polymer materials the gain of fluidity can be of 20 to 25% with size and concentration of the microspheres thoroughly chosen. A certain number of new resins is developped to elaborate composite materials with specific mechanical properties close to standard aluminium. Tensile test an ultimate stress are used to quantify the improvements of the mechanical properties. Fillers concentrations up to 30 % are obtained.
Dynamics of Drops and Bubbles in Newtonian and Viscoelastic Flows
Authors: Pillapakkam Shriram B. 
Published: December 2021

Abstract
A finite element code based on the level set method is developed for simulating the motion viscoelastic free-surfaces in two-dimensions. This method is a generalization of the one described in Osher and Sethian (1988) where the free-surface problems of inviscid and viscous fluids were simulated. The code is used to study deformation of drops in simple shear and Poisuelle flows over a wide range of dimensionless capillary (Ca) and Deborah numbers (De). Simulations show that there are limiting values of these two parameters below which the drops assume steady state shapes. For values greater than these limiting values, on the other hand, there is no steady state shape and the drop continued to deform. For a Newtonian bubble rising in a quiescent viscoelastic liquid we again find that there are limiting values of the parameters De and Ca, above which the bubble assumes a characteristic shape with a cusp-like trailing edge. The numerical results show that the viscoelastic stresses near the trailing edge are extensional and act in the direction normal to the drop surface. The front of the bubble however remains round as the local viscoelastic and viscous stresses act to round the bubble. These results are in good agreement with the experimental results.
Reduced Order Models of Viscous Flows in Turbomachinery Using Proper Orthogonal Decomposition
Authors: Epureanu Bogdan I. , Dowell Earl H. , Hall Kenneth C. 
Published: December 2021

Abstract
The proper orthogonal decomposition technique is applied in the frequency domain to obtain reduced order models (ROM) of the flow in a cascade of airfoils. The flow is described by a inviscid-viscous interaction model where the inviscid part is described by the full potential equation and the viscous part is described by an integral boundary layer model. The fully nonlinear steady flow is computed and the unsteady flow is linearized about the steady solution. A frequency domain model is constructed and validated showing to provide similar results when compared with previous computational and experimental data presented in the literature.
A cascade of airfoils forming a slightly modified Tenth Standard Configuration is numerically investigated. We show that the ROMs with only 10 to 40 degrees of freedom predict accurately the unsteady response of the full system with approximately 10,000 degrees of freedom for the subsonic case. We also show that the ROMs with 15 to 75 degrees of freedom predict accurately the unsteady response of the full system with approximately 17, 500 degrees of freedom for the transonic case. The ROMs are shown to be accurate both for a broad range of reduced frequencies and a full spectrum of interblade phase angles.
ParNAS3D: LES Spray Simulation Using an Efficient Parallel Multidimensional Upwind Algorithm
Authors: Caraeni Doru , Bergstrom Christer , Fuchs Laszlo 
Published: December 2021

Abstract
A parallel flow-solver, ParNASSD1, has been developed at LTH2 for simulations of compressible flows in aeronautical and complex industrial applications. The Large Eddy Simulation (LES) technique is used to simulate turbulent flows. The code employs an efficient algorithm, based on the Residual Distribution Scheme approach, well suited for parallelization. It has been implemented in the SPMD paradigm, and uses the PVM defacto standard for message passing.
The ParNAS3D solver has been coupled with an independent spray-module, for LES of spray in compressible flows. This was also done using the PVM message passing system.
The combined LES-spray code has been used to investigate the injection, mixing and evaporation processes of a fuel spray in a gas turbine engine. The code proved to have an excellent scalability, both when running with and without the spray module.
This is the first report on the implementation of the ParNAS3D parallel algorithm. We present also the numerical algorithm employed in our code.
Effect of Si-Al Alloy on Kinetics of Reaction-Bonded SiC Infiltration Process
Authors: Ilegbusi Olusegun J. , Yang Jijin 
Published: December 2021

Abstract
The kinetics of reaction-bonded SiC infiltration process utilizing Si-Al matrix has been investigated theoretically using a modified Washburn model. The effect of alloy composition and temperature on infiltration has been quantified. The resulting characteristics depend on alloy composition of the secondary metallic phase. Specifically, aluminum generally suppresses the infiltration rate. Increasing the temperature enhances both the infiltration capacity and reaction rate.
Search for Peptides Specifically Binding with the B7-2 Costimulatory Molecule
Authors: Kolosova E. A. , Viktorina O. E. , Chapoval A. I. , Shcherbakov D. N. 
Published: December 2021

Abstract—
The interaction of B7-1/B7-2 ligands with CD28/CTLA-4 receptors plays a key role in the regulation of the immune response. The aim of this study was to find and study peptides that interact with the human B7-2 molecule. In the course of the work, three rounds of affinity selection were carried out and individual phage clones were selected, which include peptides with varying degrees of interaction with the coregulatory target B7-2. As a result of DNA sequencing of selected phages, nucleotide sequences encoding peptides that specifically bind to B7-2 were obtained. The identified peptides can be used as a basis for the development of immunotherapeutic drugs for regulating the immune response in the treatment of oncological diseases.
Ideal cardiovascular health duration and risk of chronic kidney disease and cardiovascular disease
Authors: Cho So Mi Jemma , Jeon Justin Y , Yoo Tae-Hyun , Lee Hae-Young , Lee Yong-ho , Kim Hyeon Chang 
Published: December 2021

ObjectiveIncreasing number of clinical guidelines are adopting comprehensive cardiovascular risk assessment tools for treatment decision and disease management. Yet, little is known regarding cardiovascular risks associated with the length of favourable cardiometabolic profile. In this context, we examined whether the duration of strictly ideal cardiovascular health (CVH), based on body mass index, blood pressure, fasting glucose, total cholesterol, cigarette smoking, alcohol drinking and physical activity, in middle age is associated with risk of developing chronic kidney disease (CKD) and cardiovascular disease (CVD) in mid-to-late life.MethodsFrom the Korean Genome and Epidemiology Study Ansung-Ansan cohort, we included 8020 participants (median age 50.0 years, 47.9% male), of whom, 7854 without CKD and 7796 without CVD at baseline. Cox proportional hazards models were employed to assess CKD and CVD risks, adjusting for age, sex, education level, examination sites and renal markers.ResultsOver a median follow-up of 15.0 years, 1401 cases of CKD and 493 cases of CVD were newly developed. Compared with participants with <5 years of ideal CVH duration, HR (95% CI) of those who maintained for 5–<10 years or ≥10 years had negatively graded risks for CKD (5–<10 years, 0.63 (0.39 to 0.93); ≥10 years, 0.33 (0.15 to 0.74)) and CVD (5–<10 years, 0.83 (0.54 to 1.27); ≥10 years, 0.22 (0.08 to 0.60)). In parallel, participants with delayed decline to suboptimal level had lower disease risks compared with counterparts with consistently suboptimal CVH.ConclusionOur findings confer that maintaining favourable health behaviours and clinical risk factor levels in midlife will improve later-life cardiovascular outcomes.
Monitoring the water balance of seepage lakes to track regional responses to an evolving climate
Authors: Watras Carl J. , Michler James R. , Rubsam Jeff L. 
Published: December 2021

Understanding the causes of large fluctuations in lake water levels is important for adaptive resource management. The relatively simple water budgets of small seepage lakes make them potentially useful model systems, provided that key water balance components can be well constrained. Here, spatial variability in measured rates of evaporation (E) and precipitation (P) at the whole lake scale was investigated, and the effect on daily and seasonal water balance estimates was quantified. To estimate spatial variability, triplicate sensor platforms were deployed on and near an 18 ha seepage lake. Lake stage (S) was monitored at a single node in the lake. The water balance was closed by estimating net groundwater seepage (Gnet) analytically as Gnet = ΔS – (P – E). Instrumentation on a second seepage lake was maintained by citizen scientists to assess the potential for more widespread sensor deployments. Data were collected at 30-minute time steps for six months. The results indicate that low-cost sensor networks with single nodes to measure E, P, and ΔS provide well-constrained water budgets at daily and seasonal time scales.