bluuebunny/crossref_metadata_2025_split huggingface dataset:
Model of Biomass Concentration in Membrane Filtration Recycling Systems Subject to Single Substrate-Limited Growth Kinetics
Authors: Skerlos Steven J. , Rajagopalan N. , DeVor Richard E. , Kapoor Shiv G. , Sanford Robert A. 
Published: November 2021

Abstract
Membrane filtration has the ability to limit microbiological growth in metalworking fluids (MWFs). To appropriately design and size a membrane filtration system for this application, the rate of microbial removal must be assessed relative to microbial population (biomass) growth. This research utilizes the Monod Equation describing biomass growth limited by a single substrate to evaluate if biomass levels can be maintained below a prescribed level in a perfectly mixed MWF system. The model for predicting biomass in the MWF system is obtained by numerical solution of a system of coupled nonlinear differential equations. The model solution permits membrane filtration design and sizing decisions based on microbial growth data specific to MWF chemistries, microbial species, and manufacturing facilities. It is revealed that the ratio of the filtration rate to the MWF volume must exceed the maximum specific growth rate of microorganisms to control biomass concentrations in the system under arbitrary initial substrate and contamination levels. The control of microbial growth in the system also requires that appropriate cleaning intervals be selected for the membrane filtration process tank. The microbial rejection coefficient, which is characteristic to a given membrane, has a dominant impact on the required cleaning interval.
Cutting Fluid Mist Formation in Turning via Atomization: Part 2—Experimental Validation
Authors: Yue Y. , Gunter K. L. , Michalek D. J. , Sutherland J. W. 
Published: November 2021

Abstract
In Part 1 of this paper, models were developed to describe the formation mechanisms and dynamic behavior of cutting fluid mist. This part of the paper focuses on experimentally investigating mist formation during the turning process, and then simulating the dynamic behavior of the mist droplets, including the distribution and the mass concentration. Simulation results are compared to experimental measurements to validate the theoretical models presented in Part 1. It is seen that the model predictions adequately characterize the observed experimental behavior.
Prediction of Tool and Chip Temperature in Continuous Metal Cutting and Milling
Authors: Lazoglu Ismail , Altintas Yusuf 
Published: November 2021

Abstract
A finite difference method is presented to predict tool and chip temperature fields in continuous machining and time varying milling processes. Continuous machining operations like orthogonal cutting are studied by modeling the heat transfer between the tool and chip at the contact zone. The shear energy created in the primary zone, the friction energy produced at the rake face - chip contact zone and the heat balance between the moving chip and stationary tool are considered. The temperature distribution is solved using finite difference method. Later, the model is extended to milling where the cutting is interrupted and the chip thickness varies with time. The time varying chip is digitized into small elements with differential cutter rotation angles. The temperature field in each differential element is modeled as a first order dynamic system, whose time constant is identified based on the thermal properties of the tool and work material, and the initial temperature at the previous chip segment. The transient temperature variation is evaluated by recursively solving the first order heat transfer problem at successive chip elements. The proposed model combines the steady-state temperature prediction in continuous machining with transient temperature evaluation in interrupted cutting operations where the chip and the process change in a discontinuous manner. The mathematical models and simulation results are in satisfactory agreement with experimental temperature measurements reported in the literature.
Numerical Analysis of Cutting With Chamfered and Worn Edge Tools
Authors: Movahhedy Mohammad-R. , Altintas Yusuf , Gadala Mohamed S. 
Published: November 2021

Abstract
In high-speed machining of hard materials, tools with chamfered edges and tool materials resistant to diffusion wear are commonly used. In this paper, the influence of cutting edge geometry on the chip removal process is studied through numerical simulation of cutting with sharp, chamfered or blunt edges and with carbide or CBN tools. The analysis is based on the use of arbitrary Lagrangian-Eulerian (ALE) finite element method, which makes it possible to analyze the cutting action without having to resort to node separation methods or remeshing. Simulations include cutting with tools of different chamfer angles at a range of cutting speeds and the numerical results are compared with experimental data obtained under similar cutting conditions. The study shows that a region of dead material zone is formed under the chamfer and acts as the effective cutting edge of the tool (in accordance with experimental observations). As a result, the chip formation process is not significantly affected by the presence of the chamfer. However, the forces, the thrust force in particular, are considerably increased. The effect of cutting speed on the process is also studied and is shown to produce a significant increase in maximum temperature on the rake face.
Stability Analysis of Interrupted Cutting With Finite Time in the Cut
Authors: Bayly Philip V. , Halley Jeremiah E. , Davies Matthew A. , Pratt Jon R. 
Published: November 2021

Abstract
The stability of interrupted cutting is examined for the case in which the tool is in contact with the work piece for a small, but finite, fraction of the tooth-passing period. A model of a single degree-of-freedom tool excited by intermittent, regenerative cutting forces is analyzed. The equations are transformed into a discrete model by use of the exact analytical solution when the tool is free of the work piece, and by an approximate analytical solution (the method of weighted residuals) when the tool is in the cut. Stable combinations of spindle speed and axial depth of cut are found. These results confirm and refine predictions of additional stability regions made by Davies et al. (1999a, 2000) based on the approximation of infinitesimal time in the cut.
Single-Molecule Biomechanics: DNA and Protein Deformation
Authors: Bao Gang 
Published: November 2021

Abstract
With the advent of molecular biology and biophysics during the past decade, single-molecule biomechanics has emerged as a new field. Different techniques have been used to study the mechanical properties of DNA and protein molecules; various models have been developed to quantify the deformation of biomolecules under force. Here we review some of these advances, explore the connection between mechanics and biochemistry, and discuss the concepts, issues and challenges in developing molecular biomechanics.
A Growth Mixture Theory for Cartilage
Authors: Klisch Stephen M. , Sah Robert L. , Hoger Anne 
Published: November 2021

Abstract
In this paper we present a model of growth for cartilaginous tissues in which there exists a saturated solid matrix composed of multiple constituents that may grow and remodel independently of each other. Klisch and Hoger recently developed a general theory of volumetric growth for a mixture of ν−1 growing elastic materials and an inviscid fluid, which included a treatment of two special types of internal constraints that are relevant to cartilage. Here, that theory is specialized to construct a cartilage growth model. This theory allows the constituents of the solid matrix to grow independently of each other, and can model the evolution of the constituent pre-stresses and the tissue’s mechanical properties during developmental growth and degeneration. A simple example is presented which illustrates these features of the theory.
Real-Time Detection and Explicit Finite Element Simulation of Delamination in Composite Laminates Under Impact Loading
Authors: Minnaar K. , Zhou M. 
Published: November 2021

Abstract
A new experimental technique is developed to determine the onset and evolution of delamination in fiber-reinforced composites under impact loading. The configuration uses a split-Hopkinson bar for low-velocity impact loading and two Polytec laser vibrometer systems for real-time monitoring of the initiation and progression of delamination. The experiment allows the histories of load, displacement, and velocity of impacted specimens to be recorded and analyzed. The recorded profiles are used to characterize the damage initiation and evolution in the laminate. Numerical simulations are conducted using a cohesive finite element method. The method employs a cohesive zone model to simulate matrix cracking and interlaminar delamination and a transversely isotropic, elastic model to characterize the bulk behavior of each ply. The simulations provide time-resolved characterization of damage during the impact loading. The damage modes predicted by the numerical simulations agree well with experimental observations.
Dynamic Characterization of Multi-Functional Sandwich Composites
Authors: Vaidya Uday K. , Nelson Scott P. , Mathew Biju , Rodgers Renee M. , Hosur Mahesh V. 
Published: November 2021

Abstract
This paper deals with an innovative integrated hollow (space) E-glass/epoxy core sandwich composite construction that possesses several multi-functional benefits in addition to the providing light-weight and bending stiffness advantages. In comparison to traditional foam and honeycomb cores, the integrated space core provides a means to route wires/rods, embed electronic assemblies, and store fuel and fire-retardant foam, among other conceivable benefits. In the current work the low velocity impact (LVI) response of innovative integrated sandwich core composites was investigated. Three thickness of integrated and functionality-embedded E-glass/epoxy sandwich cores were considered in this study — including 6mm, 9mm and 17 mm. The low-velocity impact results indicated that the hollow and functionality embedded integrated core suffered a localized damage state limited to a system of core members in the vicinity of the impact. Stacking of the core was an effective way of improving functionality and limiting the LVI damage in the sandwich plate. The functionality-embedded cores provided enhanced LVI resistance due to energy additional energy absorption mechanisms. The high strain rate (HSR) impact behavior of these sandwich constructions is also studied using a Split Hopkinson Pressure Bar (SHPB) at strain rates ranging from 163 to 653 per second. The damage initiation, progression and failure mechanisms under low velocity and high strain rate impact are investigated through optical and scanning electron microscopy.
Feed Forward Plus Feedback Control of an Indexing Valve Plate Pump
Authors: Zhang X. , Nair S. S. , Manring N. D. 
Published: November 2021

Abstract
A feed forward plus feedback pressure control strategy is proposed for an indexing variable displacement pump design. Insights into the dynamics are developed to determine performance characteristics and limitations, prior to control development, and a methodology is proposed to estimate some of the parameters on-line. Theoretical as well as implementation insights for the control problem are also developed.
Two-Way Solenoid Valves in Low-Pressure Water Hydraulics
Authors: Linjama Matti O. , Tammisto Jyrki O. , Koskinen Kari T. , Vilenius Matti J. 
Published: November 2021

Abstract
The paper tests experimentally the suitability of inexpensive directly operated two-way solenoid valves for water hydraulic applications in the pressure range from 10 to 40 bars. Seven valves are tested and tested matters include the steady-state and dynamic characteristics as well as durability. Results show small delays and the durability of about ten million openings. The weak point of the valves is a small flow capacity but otherwise the valves are well suited for low-pressure water hydraulic applications. This is demonstrated by using them in a simple on/off position control of a water hydraulic cylinder.
An Open Framework for Enabling Lifelong Learning of Fluid Power Systems Design via the Internet
Authors: Richards Thomas G. , Hughes Edmund J. , Tilley Derek G. 
Published: November 2021

Abstract
Fluid Power systems design is a skilful and complex task requiring significant practical experience and heuristic knowledge gained over many years. With few formal Fluid Power design courses being taught in further and higher education, both academia and industry are seeking new methods of delivering this specialist knowledge. The Internet opens up low-cost, low-risk training opportunities for companies, particularly Small-to-Medium Enterprises, which may not be able to afford to send their staff on residential courses, and also for employees seeking career development within the context of lifelong learning. This paper describes the early stages of a project to develop an open, domain-independent, Java-based framework for the delivery of multimedia training. This framework forms part of an overall Performance Support System for trainees and professionals involved in Fluid Power systems design. Also described is a formative evaluation of the framework.
Coupled Deformations of Elastic Curves and Surfaces
Authors: Steigmann David 
Published: November 2021

Abstract
Theories of perfectly flexible elastic curves and surfaces are frequently used to describe diverse phenomena ranging from bioelasticity and fluid capillarity to rubber elasticity and the mechanics of structural networks. It is our aim here to present a treatment of the coupled response of such continua accounting for three-dimensional interactions in the presence of finite deformations and strains. A more expansive discussion of the subject of the present paper may be found in [1].
Existence and Uniqueness Results for Nonlinear Differential Equation Arising in Non-Newtonian Fluid Flow
Authors: Vajravelu K. , Cannon J. R. , Rollins D. 
Published: November 2021

Abstract
Solution for a nonlinear second order differential equation, arising in a viscoelastic fluid flow at a rotating cylinder, is obtained. Furthermore, using the Shauder theory and the perturbation technique existence, uniqueness and analyticity results are established. Moreover, the exact analytical solutions (in integral form) are compared with the corresponding numerical ones.
Failure of Impact Damaged Foam Core Sandwich Beams
Authors: Hallström Stefan , Shipsha Andrey , Zenkert Dan 
Published: November 2021

Abstract
The scope of this paper is to investigate the structural integrity of sandwich beams subjected to various load cases after local impact. The studied impact damages can be characterised as core indentation and face/core interface damage while the faces are virtually unaffected by the impact. At subsequent loading different types of post impact failure occur, depending on the size of the impact damages and the applied load.
Sandwich beams are impacted using two different impact energies and the resulting damage is inspected and measured. The measurements are used to characterise the damage and as input for analytical and finite element models in order to predict post impact failure in various load cases. The impact damages are modelled as face/core interface cracks but the approach is found to be too rough to achieve full agreement with experiments. It is concluded that the damaged face/core interface is not entirely separated but some bridging remains between the surfaces.
Static and Dynamic Buckling of Sandwich Columns
Authors: Simitses G. J. , Shen L. 
Published: November 2021

Abstract
The paper deals with the theoretical prediction of buckling loads for sandwich columns with metallic and laminated facings and foam core. The loading is a uniform axial compression, applied statically (very slowly) and suddenly with constant magnitude and infinite duration (step loading). The effect of length and boundary conditions is assessed and results are presented for the following cases for a cantilever column, a simply supported column and a clamped column for lengths of 80 inches and 240 inches. Several fiber materials are used in the laminated facings. The static critical loads are computed from three different sources and the dynamic critical loads are obtained by employing the computer code DYNA3D. For the dynamic case, the Budiansky-Roth criterion is applied.
A Lagrangian Particle Dynamics Model With an Implicit Four-Way Coupling Scheme
Authors: Smirnov Andrei , Celik Ismail 
Published: November 2021

Abstract
An implicit particle interaction mechanism is proposed, which can be applied to the problems of colliding particle jets and particle tracking in turbulent and unsteady flows. The mechanism is based on the idea of virtual particle-grid interactions and provides a linear dependence of the execution time on the number of particles. The scheme was used in conjunction with the random flow-generation procedure to simulate several cases of particle motion with different interaction mechanisms.
Proposed Use of the One-Dimensional Two-Fluid Model With Momentum Flux Parameters
Authors: Song Jin Ho , Kim H. D. 
Published: November 2021

Abstract
The dynamic character of a system of the governing differential equations for the one-dimensional two-fluid model, where the appropriate momentum flux parameters are employed to consider the velocity and void fraction distribution in a flow channel, is analyzed. In response to a perturbation in the form of a traveling wave, a linear stability analysis is performed for the governing differential equations. The analytical expression for the growth factor as a function of wave number, void fraction, drag coefficient, and relative velocity is derived. It provides the necessary and sufficient conditions for the stability of the one-dimensional two-fluid model in terms of momentum flux parameters. It is analytically shown that the one-dimensional two-fluid model is mathematically well posed by use of appropriate momentum flux parameters, while the conventional two-fluid model makes the system unconditionally unstable. It is suggested that the velocity and void distributions should be properly accounted for in the one-dimensional two-fluid model by use of momentum flux parameters.
Characterization of Cryogenic Spray Nozzles With Application to Skin Cooling
Authors: Aguilar Guillermo , Majaron Boris , Verkruysse Wim , Nelson J. Stuart , Lavernia Enrique J. 
Published: November 2021

Abstract
Cryogenic sprays are used for cooling of human skin during laser treatments of hypervascular lesions, such as Port Wine Stain birthmarks. In this work, six straight-tube nozzles, including two commercial nozzles, are characterized by obtaining photographs of cryogenic spray shapes, as well as measurements of the average droplet diameter, velocity and temperature. An evaporation model is used to predict the evolutions of average droplet diameter and temperature. The results show two distinct spray patterns—jet-like sprays for wide nozzle diameters, and cone-like sprays for narrow nozzle diameters. The wide nozzles show significantly larger droplet diameters, larger velocities and higher temperatures, as all these variables are measured as a function of distance from the nozzle. These results complement and support previously reported results, where it was shown that wide nozzles are capable of producing larger heat transfer coefficients than those obtained with narrow nozzles.
Investigation of an Open Refrigeration Cabinet Using Computational Simulations With Supporting Experiments
Authors: George B. N. , Buttsworth D. R. 
Published: November 2021

Abstract
Computational Fluid Dynamics simulations of a self-contained open refrigeration display cabinet have been performed. Experimental measurements of the cabinet operation including the refrigeration parameters and air flow conditions have been obtained. It is found that neither laminar nor turbulent simulations provide entirely satisfactory descriptions of the cabinet operation. The laminar simulation under estimates the sensible heat load on the cabinet by about 75%, and in the turbulent simulation, the sensible heat load is over estimated by approximately 50%. Similarly, the actual temperature profile within the air curtain is not accurately simulated by either the laminar or turbulent calculation, but roughly falls in between the laminar and turbulent estimates. It appears the simulation of open refrigeration display cabinets would benefit from improvements in the modelling of the low Reynolds number turbulent conditions.
Numerical Predictions and Experimental Measurements of the Near-Field of a Large Turbulent Helium Plume
Authors: DesJardin Paul E. , Tieszen Sheldon R. , O’Hern Timothy J. , Gerhart Andrew L. 
Published: November 2021

Abstract
Measurements of a large, 1 m in diameter, turbulent buoyant helium plume are taken and compared to results from numerical simulation. The experiments are carried out in Sandia’s FLAME (Fire Laboratory for Accreditation of Model by Experimentation) facility and consist of a low velocity (0.351 m/s) helium plume emitting upwards into ambient air with low velocity co-flow air supplied radially to minimize the effects of the test chamber walls. The measurement approach consists of measurements of time-resolved instantaneous velocity using Particle Image Velocimetry (PIV). The numerical simulations are based on the use of the Large Eddy Simulation (LES).
Results from this study show excellent agreement between the LES and experimental data for puffing frequency and mean and RMS streamwise velocity for downstream locations of X/Dp &gt; 0.5. For locations very near the base of the plume (i.e. X/Dp &lt; 0.5) the LES over-predicts the streamwise mean and RMS velocity and under-predicts the mean and RMS cross-stream velocities. In addition, the prediction of velocities near the base of the plume exhibit a strong sensitivity to grid resolution. This sensitivity suggests the need for modification of the current dynamic Smagorinsky and gradient diffusion turbulence models to account for the effects of subgrid scale buoyancy.
Single-Wave Peristalsis
Authors: Tadjfar M. , Yamaguchi T. , Himeno R. 
Published: November 2021

Abstract
Single-wave peristalsis propagating on the wall of a cylindrical tube is simulated. The unsteady, three-dimensional, incompressible Navier-Stokes equations are solved numerically. The flow is computed with moving boundaries and moving grid. A second-order in time and third-order upwind finite volume method for solving time-accurate incompressible flows utilizing pseudo-compressibility technique is used. In this study, the flow of an axisymmetric “tear-drop” shaped, single, peristaltic wave is analyzed. The effect of transient state on the flow is limited. The three-dimensional effects are also limited to the transient state. The lubrication theory application to the single wave flow may not be appropriate due to its inability to adjust the pressure nonlinearly.
Parallel Solver for Blood Flow in Human Vascular System
Authors: Tadjfar M. , Yamaguchi T. , Himeno R. 
Published: November 2021

Abstract
In order to simulate blood flow in human vascular system, the unsteady, three-dimensional, incompressible Navier-Stokes equations are solved numerically. The solver is capable of dealing with moving boundaries and moving grids. A second-order in time and third-order upwind finite volume method for solving time-accurate incompressible flows utilizing pseudo-compressibility technique is used. For parallel execution, the flow domain is partitioned. Communication between the subdomains of the flow on Riken’s VPP/700E supercomputer is implemented using MPI message-passing library. The code is capable of running on both shared and/or distributed memory architectures.