bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Universal Bubble-Growth Equation for Pure Liquids and Binary Solutions With a Non-Volatile Solute
Authors: Miyatake Osamu , Tanaka Itsuo , Lior Noam 
Published: July 2023

Abstract
A simple equation suitable for predicting the growth rate of a vapor bubble in uniformly-superheated pure liquids and in binary solutions with a non-volatile solute was developed. The equation also improves on the popular pure-liquid bubble growth expression of Mikić et al. (1970) in that it is valid throughout the bubble growth history, i. e. in the surface-tension-, inertia-, and heat-transfer-controlled regimes, it accounts for bubble growth acceleration effects, and uses correctly-related and variable fluid properties. It was found to agree very well with experimental data for pure water and for aqueous NaCl solutions As the bubble growth in superheated solutions with a non-volatile solute was found to be quite insensitive to diffusion and non-equilibrium effects in a broad range of common solution properties, this equation is likely to be universally valid for many liquids and solutions.
Analysis of Freezing in an Eccentric Annulus
Authors: Zhang Yuwen , Faghri Amir 
Published: July 2023

Abstract
Freezing in an eccentric annulus is investigated numerically by using a temperature transforming model. Since the effect of the heat conduction along the circular direction on the growth of the freezing layer is very small, an analytical solution by employing integral approximate method is proposed. The freezing rate obtained by the analytical solution agreed very well with that of the numerical solution, although the analytical solution is much simpler than the numerical solution. The effects of the eccentric annulus geometric structure on the freezing process is also investigated.
Finite Element Analysis of a Biaxially Loaded Woven Fabric Composite Laminate With a Central Hole
Authors: Kelkar Ajit D. , Chaphalkar Pramod , Sankar J. 
Published: July 2023

Abstract
Textile composites are structural materials reinforced by a network of fibers and are formed by processes such as braiding, weaving, or knitting. Woven fabric composites are two dimensional constructions where the warp and fill fiber tows are woven into each other to form a layer. The layers are impregnated, stacked in predetermined orientations and cured to obtain composite laminates. The composite laminates thus formed have good properties in mutually orthogonal directions as well as more balanced properties and better impact resistance than the unidirectional laminates.
Woven fabric laminated composites are likely to play a key role in modern design, principally owing to their attractive strength to weight and stiffness ratios. To compete effectively with other materials, these woven fabric laminates are often utilized in plate form with cutouts in them. Analytical models that predict the moduli, Poisson’s ratios from the weave architecture and the properties of the constituents are desirable. In this paper, a plain weave model is presented to develop the constitutive relationships (i.e., A, B and D matrices). The results from the plain weave model are used in conjunction with the classical laminate theory and linear finite element model of a woven fabric laminate to predict the stress concentration around a central hole. A graphite/epoxy material system was used. The woven fabric plies were assumed to be of constant thickness and were arranged symmetrically about the mid plane. In addition to woven fabric plies, regular unidirectional plies were also stacked at different angle orientation. The square plate with a hole was then subjected to biaxial in-plane loading. The stress concentration factors were determined by computing the ratio of stresses around the hole to those without hole at the same location.
Reliability of Welded Joints With Short Fatigue Cracks
Authors: Lanning David B. , Shen M.-H. Herman 
Published: July 2023

Abstract
This study investigates the reliability of a cracked welded T-joint typically found in offshore structures. In the initial stages of crack propagation, when the crack is very small, propagation rates have been found to vary from those determined using traditional linear elastic fracture mechanics, possibly resulting in significant differences in the predicted lifetime of a structure. This effect is shown in a reliability analysis that uses measurements of crack closure tests performed by other workers to predict the lifetime of a welded T-joint with a surface crack located at the toe of the weld. The reliability in terms of fatigue lifetime is calculated using Paris’ crack propagation equation based upon an effective stress intensity factor calculated with Newman and Raju’s formulation for a cracked flat plate and modified with a weld magnification factor. The obtained reliabilities are then compared to those found without short crack considerations.
Implications of Anisotropy and Structural Couplings on Dynamics and Instability of Spinning Thin-Walled Beams
Authors: Song Ohseop , Librescu Liviu 
Published: July 2023

Abstract
The problem of the mathematical modeling of anisotropic beams rotating with constant angular speed about the longitudinal body-axis fixed in the inertial space is addressed. The analysis is conducted in the context of thin-walled anisotropic composite beam theory which incorporates a number of non-classical effects. Among them there are the transverse shear, as well as primary and secondary warping effects. Special attention is paid to the influence played by anisotropy of constituent materials, boundary conditions and spinning speed on forward and backward precession frequencies and on instability speed. A number of applications involving both axisymmetric and doubly symmetric cross-section beams are presented and pertinent conclusions are outlined.
Investigation of Seismic Response for a Quarter Scale Reactor Containment Model
Authors: Jang Young-Sun 
Published: July 2023

Abstract
The effect of soil-structure interaction is an ongoing subject of experimental and numerical studies, since the seismic responses of structures play an important role in design of nuclear power plants. As a result, a quarter scale model of a pressurized-water reactor building was constructed by an international research consortium Hualien, Taiwan. This region of Taiwan is a seismically active area. In this study, the seismic responses due to an earthquake of magnitude 5.6 which occurred on January 20, 1994 have been used for comparison with numerical results. The sub-structure method and the hybrid method are adopted to analyze the structural responses, and we investigate the differences between numerical results of the two methods in detail.
ASME/US Bureau of Mines Investigative Program on Vitrification of Combustion ASH/Residue: Findings and Conclusions
Authors: Hollander Herbert I. , Decesare Roger S. , Hoecke David A. , Plumley Arthur L. 
Published: July 2023

Abstract
Vitrification of the residues from thermal processes into a dense, grainless, amorphous, glasslike material may provide an opportunity to permanently relieve our concerns regarding aquifer contamination and ... if the vitrified products are utilized, conserves those land areas which are suitable for disposal for those discards for which we have not as yet found a practical use.
This discussion briefly describes and illustrates the implementation of the $1.2 million ASME/U.S. Bureau of Mines (BuMines) investigative program. The discussion will cover the scope and methods followed, equipment systems employed, and areas of investigation, as well as findings and conclusions in determining the potential effectiveness of sequentially vitrifying significant quantities of ash/residue from (a) three different types of mass burning municipal solid waste energy recovery facilities, (b) a regional wastewater treatment plant sludge combustor, and (c) air quality control products from a large energy recovery facility that burned refuse-derived-fuel while utilizing a fraction of the electric energy recovered. The project also identified potential beneficial applications for the resulting products, the environmental implications and projected overall economics.
Investigation of Remediation of Soil Contaminated With Diesel Fuel Using Air Venting
Authors: Fotinich Artemiy , Joo Youngcheol , Dhir Vijay K. 
Published: July 2023

Abstract
Soil venting is an effective and widely used method to remediate hydrocarbonically contaminated soils. A non-isothermal model, proposed by Lingineni and Dhir (1992) to predict evaporation rates of organic contaminants in an unsaturated non-sorbing soil, was incorporated into a computer code capable of numerically analyzing multi-component diesel fuel. The program accounts for 14 major components of diesel fuel as well as for temperature variation due to evaporation of the contaminant, preheating of the venting air, and heat loss. Experiments to verify the model performance were conducted in a one-dimensional column. Temperature readings from thermocouples located in the test section were recorded during the experiment and the composition of hydrocarbons in the effluent air was also monitored. The effluent gas samples were extracted at the selected times and analyzed with the help of a gas chromatograph.
The experimental temperature readings and vapor composition in the extracted samples are in general agreement with the predictions from the computer program. The results show that the diesel components are removed according to their volatility with the higher volatility components being removed first. It is also found that preheating of the venting air can significantly increase the removal rates of the components.
Chaotic Fluctuations of Soot Particles in Turbulent Diffusion Flames: Experimental Data and Logistic Map Models
Authors: Mengüç M. P. , McDonough J. M. , Manickavasagam S. , Mukerji S. , Swabb S. , Ghosal S. 
Published: July 2023

Abstract
In this paper, we discuss an experimental and theoretical methodology to characterize soot volume fraction fluctuations in turbulent diffusion flames. The approach is based on the hypothesis that the fluctuations of properties in turbulent flames are deterministic in nature, rather than statistical. Experiments are conducted to measure the scattered light signals from fluctuating soot particles along the axis of an ethylene-air diffusion flame. Using these time series data, the corresponding power spectra and delay maps are determined. The results indicate a period doubling sequence, suggesting a route to chaos. The psds from experiments are modeled using a series of logistic maps. These logistic maps can be used in simulation of the fluctuations in these type of flames, without extensive computational effort or sacrifice of physical detail. Availability of accurate models of these kinds allows investigation of radiation-turbulence interactions at a more fundamental level than previously possible.
Enhancing Burner Diagnostics and Control With Chaos-Based Signal Analysis Techniques
Authors: Fuller Timothy A. , Flynn Thomas J. , Daw C. Stuart 
Published: July 2023

Abstract
Driven by economic pressures and government emissions regulations, the electric power industry is moving toward tighter control of boilers to improve plant efficiency and reduce emissions. Tighter control depends on better diagnostic tools that discriminate short-time-scale flame patterns and correlations between those flame patterns and overall performance. Our research indicates that improved discrimination of short-time-scale patterns in boilers can be achieved by combining traditional data analysis techniques and chaotic time series analysis. Suggested analysis tools and data acquisition procedures are described, along with example results for measurements from a low-NOx pulverized coal combustor.
Dynamic Stress Behavior in Catalytic Combustors
Authors: Boehman André L. , Simons Jeffrey W. , Niksa Stephen J. , McCarty Jon G. 
Published: July 2023

Abstract
Dynamic stress behavior during catalytic combustion of methane has been simulated under transient warm-up, cool-down and cyclic conditions. The numerical model combines a two-dimensional solution to the transport equations, solution of an energy balance on the monolith wall, and the NIKE3D structural analysis code to predict thermal stresses. The model also includes a detailed heterogeneous kinetics model for a proprietary palladium oxide (PdO) catalyst, but the model ignores gas phase reactions. Results illustrate that thermal stresses as high as 630 MPa can form during transient operating modes, which risks structural failure of the ceramic monolith. The maximum computed thermal stress concentrations occur near the inlet of the monolith. Peak transverse stresses (which act to form axial cracks) typically form near the inlet and centerline of the monolith structure, while peak axial stresses form near the edges of the flat plate that represents the monolith structure. Increasing the preheat temperature of the incoming fuel and air mixture lessens the peak thermal stress. To a first approximation, the magnitude of the peak transverse stress during any transient cycle considered with our model can be estimated from the maximum value of the gradient in the computed temperature profiles.
NOx Formation and Control in Radiatively/Conductively-Stabilized Pulverized Coal Combustors: A Numerical Analysis
Authors: Kim Changsik , Lior Noam 
Published: July 2023

Abstract
In an attempt to study ways for reducing NOx emissions from radiatively/conductively stabilized combustors (RCSC) for pulverized coal, a comprehensive conjugate heat&mass transfer and reaction kinetics model of that combustor was developed. As compared with a simple three-reaction model, the radiation intensity distribution obtained by a more comprehensive one shows a substantial decrease in the flame region. The effect of a 10% deviation in the diffusion coefficients on the results was found to be negligible, indicating that the use of binary coefficients instead of those for a multi-component system may be good enough in such combustion modeling. Flame location was found to have little effect (∼6%) and internal wall emittance an insignificant effect, on NO emissions. However, it was found that these emissions could be lowered significantly by lowering the flame temperature, accomplished by increasing the excess air ratio.
Dynamic Characterization of Smart Structures for Active Vibration Control Applications
Authors: Wilson D. G. , Searle I. , Ikegami R. , Starr G. P. 
Published: July 2023

Abstract
The purpose of this paper is to report on the stages required to develop smart structures for active vibration control for application to lightweight robots. The authors have designed, analyzed, fabricated, and tested several prototype smart structures. The structures were developed using graphite/epoxy material with embedded piezoceramic patches for both actuation and sensing. Finite element models were used to predict the dynamic characteristics of these composite beams. A series of tests were performed to confirm the static and dynamic characteristics of the smart structures for active vibration control applications.
Micromechanical Modeling of Material Damping in Coated Fiber Polymer Composites
Authors: Cartian Ioana , Gibson Ronald F. 
Published: July 2023

Abstract
The major objectives of this paper are to describe preliminary results from a systematic analytical study of the improvement of damping in polymer composites at the micromechanical level by the use of special fiber coatings. Since shear deformation is essential for viscoelastic damping in polymers, and large shear strains are generated near the fiber/matrix interface in composites, it is believed that the use of special viscoelastic polymer fiber coatings will be an effective way to improve damping in such composites. The analysis was carried out by developing finite element, theory of elasticity, and mechanics of materials models. A strain energy approach was implemented in both the finite element and theory of elasticity formulations to analyze the damping in the coated fiber composites. The models, based on a “representative volume element” or repeating element of a continuously reinforced fiber composite, are used to study damping and stiffness under longitudinal normal (LN), transverse normal (TN), transverse shear (TS) and longitudinal shear (LS) loading. Of particular interest are hybrid composites having a mixture of coated and uncoated fibers, since coating all the fibers would cause unacceptable reductions in other important properties like strength and stiffness. In order to analyze hybrid composites, two and three dimensional multi-cell finite element models have been developed. Parametric studies were done with particular emphasis on the effect of fiber coating thickness and coating volume fraction in order to improve the damping of the composite structure. Large shear strain deformations occur in the fiber coating material since the stiffness of the coating material is lower than that of the fiber or the matrix. This condition leads to improved damping in the coated fiber reinforced composite. A rapid increase in damping with increasing coating volume fraction was found for the cases of TN, TS, and LS loading. For the case of LN loading, damping does not change much with increasing coating volume fraction. Good agreement for the damping and stiffness results was obtained by using the finite element, elasticity, and mechanics of materials formulations.
Mathematical Model and Calculation Method of Thermodynamic Characteristics in the Flow of Chemically Reactive and Inert Rheologically Complex Media
Authors: Nazmeev Yuri G. 
Published: July 2023

Abstract
The paper presents a mathematical model and a method of calculation of diskrete values of thermodynamic characteristics in a flow of Theologically complex liquids. Our approach is based on the solution of a conjugate set of non-linear differetial equations in therms of partial derivatives of a second order. The mathematical model comprises: a set of equations of motion and continuity; a set of equations of heat and mass transfer a rheological equation of medium state; a macrokinetic model of chemical reaction; the residence time function and the molecular-mass distribution obtained with its help as well as a set of equations to calculate chemical and thermal exergy, enthalpy and entropy. The method can also be applied to calculate thermodynamical characteristic values for inert media. Both Newtonian and Theologically complex media, including non-linearly viscoelastic ones, may be subject to calculation. The method can be applied to a wide range of channel shapes and cross-sections. The versatility of the method has been confirmed by the calculation of several technological processes of polymer chemistry.
Quantitative Description of Vortical Region Length of Non-Newtonian Fluids Through an Abrupt Contraction
Authors: Liang J. Z. , Ling Z. Y. , Li R. K. Y. , Tjong S. C. 
Published: July 2023

Abstract
In the present paper, the flow of a viscoelastical fluid through a sudden contraction duct was discussed. Based on previous work, the authors proposed some equations for estimating the vortical region length (Lv). The values of the Lv during capillary extrusion of a rubber compound were calculated proximally. It was found that the ratio of Lv to reservoir diameter was about 0.14–0.32, which it was decreased with a rise of temperature or decreasing shear rates.
Couette Flows of Liquid Crystal Polymers
Authors: Wang Qi 
Published: July 2023

Abstract
Using the BMAB theory with the Doi closure approximation and a biaxial representation of the orientation tensor, we demonstrate that the steady states of liquid crystal polymeric Couette flows between two concentric, circular cylinders in relative rotation exhibit biaxial symmetries. Therefore, two order parameters and a triad of directors must be employed to model average molecular orientation in the flow. With two directors confined to the plane orthogonal to the axis of rotation, stable steady states may exhibit flow-aligning, log-rolling and mixed flow-aligning and log-rolling behavior depending on the initial orientation between the two cylinders. The orientational pattern and the degree of orientation is sensitive to the value of the polymer concentration, the anisotropic drag coefficient and the ratio of the radius of the two cylinders. Molecules achieve higher degree of orientation at the wall of the inner cylinder than at that of the outer cylinder in the flow-aligning regime, and vice versa in the log-rolling regime.
Calculation of Relaxation and Retardation Spectra Using the Tikhonov Regularization Method: Application to Emulsions
Authors: Madiedo J. M. , Muñoz J. , Gallegos C. 
Published: July 2023

Abstract
Flocculated oil-in-water emulsions exhibit very complicated relaxation spectra, showing different regions depending on oil and emulsifier concentrations, processing parameters, etc. In this work, the linear viscoelastic behavior of concentrated oil-in-water emulsions stabilized by two sucrose stearates with different hydrophilic-lipophilic balances has been studied. This characterization has been achieved by calculating the relaxation and retardation spectra of the emulsions, using regularization techniques. With this aim, oscillatory shear and creep compliance tests, in the linear viscoelasticity region, were carried out in a controlled-stress rheometer. Three different regions in the relaxation spectra of these systems have been identified: the transition region at low relaxation times; an intermediate plateau region; and a pseudo-terminal region at long relaxation times, characterized by a tendency to a crossover of G′ and G″ in the frequency sweep curves. The evolution of these regions depends mainly on the characteristics of the sucrose stearates used and has been related to their aqueous phase behavior.
Reversible Aggregation and Nonlinear Rheology of Fine Suspensions
Authors: Buyevich Yuri A. , Zubarev Andrei Yu. 
Published: July 2023

Abstract
In this paper, we develop a tentative rheological model for finely dispersed systems whose particles are capable of forming stable aggregates under shear flow conditions. The main achievement of this paper consists in putting forward a physical model for an aggregative structural transition in a flowing dispersion. When shear rate reaches a certain threshold value, rapid aggregation occurs, the aggregates originate as a result of reversible coagulation of particles in a secondary potential minimum characteristic of the molecular interparticle interaction. The aggregated system consists of an assemblage of aggregates that contain many particles and that are suspended in an ambient media that represents a suspension of single individual particles. Aggregation terminates and aggregates disappear when shear rate exceeds another critical value. The aggregated system effective viscosity is determined by the volume concentration of the aggregates and by the volume concentration of single particles in the ambient suspension within the interstices. Since these concentrations, as well as the aggregate size, depend on the shear rate, the effective viscosity is a nonlinear function of shear rate. Our model offers an opportunity to describe both shear-thickening and shear-thinning of aggregating dispersions within the frames of a unified approach.