bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of Roll Grinding System Dynamics With Rotation Speed Control
Authors: Yuan LiHong , Järvenpää Veli-Matti , Keskinen Erno , Cotsaftis Michel 
Published: November 2021

Abstract
This paper is a discussion of a numerical simulation and a numerical stability study of the dynamics of a paper machine roll grinding process with an additional time delay effect, which is originated from a shape error trace on the surface of the roll under grinding. The simulation model presents the dynamic interaction between the roll and the grindstone during the process, the lateral deformations of the roll and the torsional rigid body vibration system of the roll and the grindstone with its drive. The normal and tangential forces of the grinding contact based on the wear theory and the driving torques of the roll and the grindstone with PD-controllers are considered. The mechanical model of the roll is described as a simply supported continuous beam element expressed in an eigenvector basis and in rotating coordinates. The time delay equation is based on the classical linear time delay theory with a constant delay. The numerical simulations conducted in time domain provide a view to observe the dynamic behavior and the stability of this grinding process and a tool for the design, analysis and verification of industrial roll grinding measurements in the future.
Nonlinear Dynamics Analysis of a Printed Wiring Board With Simple and Clamped Boundary Conditions
Authors: He Xiaoling 
Published: November 2021

Abstract
Dynamic response of a printed wiring board (PWB) is analyzed in nonlinear dynamics approach. Equations of motion for the simply supported PWB and the clamped PWB are obtained by the Galerkin’s method. A 2-layer plastic PWB made of isotropic laminates is studied for its boundary condition effect on the vibratory behavior in deflection and stresses. Failure due to plane stress interaction is estimated based on the composite failure criteria.
It is found that nonlinear resonance occurs almost periodically in both frequency and temporal domain. Load frequency and magnitude affect the deflection response under different boundary conditions. Resonance behavior is critical in PWB failure prediction based on the stress analysis. The analytical results can be extended to the nonlinear dynamics analysis of the thin laminated plate.
Analysis on an Oscillator With Delayed Feedback Near Double Hopf Bifurcations
Authors: Yu P. , Yuan Y. 
Published: November 2021

Abstract
This paper considers the effect of time delayed feedbacks in a nonlinear oscillator with external forcing. The particular attention is focused on the case where the corresponding linear system has two pairs of purely imaginary eigenvalues at a critical point, leading to double Hopf bifurcations. An analytical approach is used to find the explicit expressions for the critical values of the system parameters at which non-resonant or resonant Hopf bifurcations may occur. A fourth-order Ronge-Kutta numerical integration scheme is applied to obtain the dynamical solutions in the vicinity of the critical points. Both the cases with and without the external forcing are considered. It has been found the system exhibits very rich complex dynamics including periodic, quasi-periodic and chaotic motions. Moreover, a sensitivity analysis is carried out to show that chaotic motions are very sensitive to the time delay. This suggests that the time delay can be used: (1) to control bifurcations and chaos; and (2) to generate bifurcations and chaos.
Dynamics of a Nonlinear Mechanical Resonator in Micro-Electro-Mechanical Systems
Authors: Luo Albert C. J. , Wang F. Y. 
Published: November 2021

Abstract
Equilibrium, natural frequency and responses of a mechanical resonator with capacitors in a simplified micro-electro-mechanical system (MEMS) are determined. Under application of alternating current (AC) voltage, the resonant conditions for such a system are obtained. The chaotic motions in the vicinity of a specified resonant-separatrix are investigated analytically and numerically. For a given AC voltage amplitude, the AC frequency bands are obtained for chaotic motion in the specific resonant layers and resonant motions, and such chaotic motions can be sensed very easily by the output transducer in MEMS.
The Pressure Field Around a Vibrating Cylinder in a Fluid Annulus
Authors: Reynolds Robert R. , Cole Jack H. , Yuan Zhen 
Published: November 2021

Abstract
The influence of geometry on the pressure field within the confined, water-filled annulus between a central, vibrating cylinder and an outer, rigid enclosure is determined. A two dimensional model is constructed using the finite element (FE) method and parameters are identified to characterize the eccentricity of the nominal cylinder position, the size of the annulus relative to the inner cylinder and the degree to which the annulus is not circular (i.e. it is elliptic). The FE solution is verified using a closed form solution for the special case of a concentric cylinder and annulus. It is shown that the system acts as a force multiplier. Analyses of the asymmetrical geometries indicate that while the pressure field on the surface of the cylinder and enclosure can be highly asymmetric, the system is relatively insensitive to minor variations in annulus shape except when the vibrating cylinder is not centrally located within the fluid region or the annulus size itself is small.
4WID: A New Concept in Electrical Vehicles
Authors: Esmailzadeh E. , Goodarzi A. , Vossoughi G. R. 
Published: November 2021

Abstract
A comprehensive new dynamic model of a four-wheel independent drive electric vehicle has been developed and different types of the motor control laws were addressed. The first part of this study deals with the full description of the model scope in which the structure of the model including the sub-models has been fully developed. Subsequently, the sub-models including the tire sub-model, the body motion, and the motor dynamics were investigated, and the computer model of the vehicle has been simulated. Finally, the proposed motor control laws and the vehicle dynamic behavior of the vehicle were presented. Detailed analyses of the vehicle performance and comparison of the simulation results were also carried out.
Structural Sound Radiation on a Reflecting Plane by the Boundary Point Method
Authors: Cui Z. , Huang X. Q. 
Published: November 2021

Abstract
In this paper, the structural sound radiation from a reflecting plane is studied. The Green Function is used to develop a formula, which is implemented in applying the boundary point method to a semi-infinite region. A detailed description of this method is presented. Through the theory and numerical examples, it is shown that this method compared to other available ones is simple and efficient.
Development of a Driver Assistant System for Improving Passenger Ride Comfort of Automobiles
Authors: Wang Feng , Ma Ni , Inooka Hikaru 
Published: November 2021

Abstract
This paper describes the development of a driver assistant system for reducing passenger ride discomfort of automobiles. Based on results of psychophysical experiments of subjective ride discomfort evaluation, the ride discomfort caused by the velocity fluctuation of an automobile was investigated and a linear multiple regression model that evaluates the ride discomfort index (RDI) using longitudinal acceleration and jerk of the automobile as explanatory variables was proposed. A driver assistant system that evaluates the RDI and informs the driver of the RDI in real time using a microcomputer was developed. Experiments showed that with the help of the system, a driver can improve his/her driving skills and modify his/her driving behavior to reduce passenger ride discomfort and provide passenger-friendly maneuvers, thus verified the efficacy of the proposed driver assistant system.
The Integration of Reliability Techniques As an Aid to the Design Optimisation of an Earth Moving Machine
Authors: Arcidiacono G. , Delogu M. 
Published: November 2021

Abstract
The paper describes the design and structural optimisation of a mechanical system from the functional, safety, reliability and cost viewpoints, using a flexible, rapid approach which was developed from the integration of two methodologies: Axiomatic Design and FMEA. In particular, thanks to the information obtained from Axiomatic Design, FMEA is not carried out on the entire system but only on the components and subsystems which are more critical. This makes it possible to establish an order of priority for intervening on components or Design Parameters of a system which can be applied both prior to designing the system or in the diagnostic and validation phase of an already existing product. This approach has been validated by its application to the electro-hydraulic command of the working device of an Orenstein & Koppel (O&K) earth-moving machine.
Control Law for an Engine Starter Clutch in a Parallel Hybrid Electric Vehicle
Authors: Baraszu Robert C. , Cikanek Susan R. 
Published: November 2021

Abstract
This paper describes the control law for engaging and disengaging a dry clutch used for connecting an engine to a drivetrain in a Parallel Hybrid Electric Vehicle (PHEV). Brief descriptions of the component models and subsytem controllers are presented along with the powertrain’s dynamic equations. The engine clutch control is described in detail, including engagement and disengagement simulations. The hybrid drivetrain, (Figure 1), includes a conventional 2.01 spark-ignited, internal combustion engine and an dry clutch attached directly to an engine flywheel. The output of the dry clutch is connected to a starter/alternator (S/A) that starts the engine, charges and discharges a high-powered energy storage device and provides additional motive power. The powertrain is completed by a converterless automatic transmission connected to a differential and halfshafts that drive the front wheels. The engine clutch control strategy is presented together with simulations that demonstrate system performance.
Multiple Target Tracking in the Adaptive Cruise Control Environment Using Multiple Models and Probabilistic Data Association
Authors: Caveney Derek , Hedrick J. Karl 
Published: November 2021

Abstract
The multiple target tracking (MTT) performance of a new combination of the fuzzy interacting multiple model (FIMM) algorithm and the probabilistic data association filter (PDAF) is investigated. The ability of a set of these FIMMPDAFs to maintain the tracks of multiple targets in a cluttered adaptive cruise control (ACC) environment is compared to that of the likelihood approach, the IMMPDAF. The differences between the two methods are highlighted and simulation results for a typical highway driving scenario demonstrate the performance of each approach. These results show that both the IMMPDAF and FIMMPDAF strategies are capable of tracking multiple vehicles with low RMS position errors, while the FIMMPDAF appears to detect the initiation of a target maneuver more rapidly by adjusting model probabilities more quickly.
Effect of Multi-Modal Forcing on Thermal Transport in a Co-Axial Combustor Geometry
Authors: Chandra P. R. , Lau Chun L. , Acharya S. 
Published: November 2021

Abstract
This paper investigates open-loop control of the mixing between an inner stream and an outer stream in a coaxial combustor geometry. The inner and outer air streams enter the combustor geometry at different temperatures and mimic a gaseous fuel and combustion air stream respectively. Of specific interest in this study is the behavior of the coherent structures in the coaxial jet streams, and the manipulation of these coherent structures with controlled perturbation to enhance jet-spreading and scalar-mixing. The spectra of the unforced flow reveal the presence of a dominant coherent mode at 100 Hz (identified as the fundamental mode fo), as well as 150 Hz (3 fo/2) and 300 Hz (3 fo). Single-mode forcing of both the inner-jet and the outer-jet at 100 Hz, 150 Hz, 300 Hz, and 1 kHz is explored, and attention is focused on the spreading of the inner-jet shear layer and the outer-jet shear layer. It is observed that the 300 Hz mode shows the greatest enhancement in the spreading rate of the velocity shear-layer in the near field (x/D &lt; 1), while downstream of x/D = 1, the 100 Hz appears to show the most significant effect. Scalar mixing is also significantly enhanced, with the 300 Hz forcing showing the largest enhancement. Dual-mode forcing is also investigated with 100 Hz inner-jet, 300 Hz outer-jet forcing and 300 Hz inner-jet, 100 Hz outer-jet forcing. The 100 Hz inner-jet, 300 Hz outer-jet forcing is shown to lead to greater enhancements in scalar mixing man all other cases considered.
Natural Convection on a Vertical Isoflux Plate With a Downstream Unheated Extension and a Parallel Shroud
Authors: Manca Oronzio , Musto Marilena , Naso Vincenzo 
Published: November 2021

Abstract
Air natural convection on a vertical isoflux plate with a downstream unheated extension and a facing parallel shroud has been experimentally investigated, for different values of the wall heat flux and of the geometrical parameters. In most configurations the adiabatic extension improves the thermal performance of the channel. For the larger values of the channel aspect ratio (Lh/b = 10) the system with a geometrically asymmetric chimney performs better than that with a geometrically symmetric chimney. Maximum wall temperatures and average Nusselt numbers are correlated to the thermal and geometrical process parameters, in the ranges Ra* B/b = 3.102 − 105 and L/Lh = 1.5–4.0.
Local Heat Transfer and Pressure Drop for Finned-Tube Heat Exchangers Using Oval Tubes and Vortex Generators
Authors: O’Brien James E. , Sohal Manohar S. , Wallstedt Philip C. 
Published: November 2021

Abstract
This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with an elliptical tube and one or two a delta-winglet pairs. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficients were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over a Reynolds number range based on duct height of 670–6300.
Pressure drop measurements have also been obtained for similar elliptical-tube and winglet geometries using a separate single-channel, multiple-tube-row pressure-drop apparatus. The pressure-drop apparatus includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided.
Mean heat transfer results indicated that the addition of the single winglet pair to the oval-tube geometry yielded significant heat transfer enhancement, averaging 38% higher than the oval-tube, no-winglet case. The corresponding increase in friction factor associated with the addition of the single winglet pair to the oval-tube geometry was very modest, less than 10% at ReDh = 500 and less than 5% at ReDh = 5000.
High Speed Photographic Investigation of Liquid-Vapor Interface and Contact Line Movement During CHF and Transition Boiling
Authors: Kandlikar Satish G. , Steinke Mark E. 
Published: November 2021

Abstract
As the Critical Heat Flux (CHF) condition is approached, a thin layer of vapor begins to form between the heated surface and the liquid. The mechanisms leading to the formation of this interface are not clearly understood. The present investigation focuses on obtaining high-speed video images of the liquid-vapor interface and the solid-liquid-vapor contact line. The movement of the interface and the contact line is expected to provide information regarding conditions existing just prior to reaching the CHF.
The experimental setup consists of a droplet impinging on a heated surface in a controlled environment. Two high-speed cameras capable of capturing up to 8000 frames per second are employed to obtain two views of the droplet. The accompanying software is used to determine the velocity and other relevant information regarding the interface. The results are used to discuss the applicability of the CHF and transition boiling models available in literature.
Nanoscale Thermal, Electrical, and Thermoelectric Measurements Using Batch-Fabricated Scanning Probes
Authors: Miner Andrew C. , Li Deyu , Tan Kwong-Luck , Shi Li , Majumdar Arun 
Published: November 2021

Abstract
Recent interest in thermal, electrical and thermoelectric properties of thin films and nano-structures has driven the development of measurement tools. One promising technique integrates sensors into Atomic Force Microscope (AFM) probes to investigate thermal, electrical, and thermoelectric properties on nanometer scales. Our group has successfully developed such probes and used them to investigate thermionic coolers and the carbon nanotubes. In this paper, we will discuss the successes and deficiencies of these measurement methods, and present new nanoprobe designs, which address these deficiencies. The majority of AFM systems use laser reflectance to monitor the probe position. Current designs are adversely effected by the portion of absorbed laser energy in two ways: probe temperature rises and creates bending due to a bimaterial effect, and the variability of the laser input adds error to the sensor measurement. The finite thermal resistance between the probe and sample creates a temperature drop, contributing to experimental error. This work proposes refined microfabrication techniques to reduce the bi-material effects, alternative probe positioning schemes, and improved sensitivity of thermal measurement to significantly improve the reproducibility and accuracy of nanoscale property measurement.
Explicit Analytical Solutions of Natural Convective Heat Transfer in Saturated Porous Medium
Authors: Zhang Na , Cai Ruixian , Wang Wei 
Published: November 2021

Abstract
Analytical solutions have their own theoretical meaning; as benchmark solutions, they can also guide the computational methods. Therefore, six algebraically explicit analytical solutions are derived for the natural convective heat transfer nonlinear partial differential equation set to enrich the heat transfer theory and to promote the development of computational heat transfer.
Theoretical Thermal Conductivity of Soils at High Temperatures
Authors: Gori Fabio , Corasaniti Sandra 
Published: November 2021

Abstract
The prediction of the thermal conductivity of soils is important in several phenomena related to ground. Among the practical applications at high temperatures are geothermal energy extraction, enhanced oil recovery, radioactive waste storage, ground heat pump and heat exchanger, forest fires and related problems. Some experimental results are available in the literature at temperatures in the range 30°C – 90°C. The theoretical model of the present paper assumes the unit cell of the porous medium as composed of a cubic space with a cubic solid particle at the center. The thermal conductivity of the porous medium is evaluated with the assumption of parallel isotherms. The water in the porous medium is distributed around the solid particle according to the phenomena of adsorption and capillarity. The thermal conductivity of the gas present within the pores takes into account the thermal conductivity of the water-saturated vapor and dry air without enhanced vapor diffusion and with the assumption of a linear variation of the relative humidity from zero water content to the field capacity. The predicted results, compared to the experimental data of soils at high temperatures show that the agreement is very good at moderate temperatures (30–50°C) and fairly acceptable at 70°C. At high temperature (90 °C) the predictions are somewhat higher than the experiments but a better agreement could be obtained decreasing the thermal conductivity of the water-saturated vapor. In any case the trend of the theoretical predictions is in very good agreement to the experiments also at high temperatures.
A Continuum Model for the Liquid-to-Gas Phase Change and Growth in a Porous Medium at Constant Withdrawal Rates
Authors: Tsimpanogiannis Ioannis N. , Yortsos Yanis C. 
Published: November 2021

Abstract
We develop an effective continuum model to describe the heterogeneous nucleation and subsequent growth of a gas phase from a supersaturated, slightly compressible binary liquid in a porous medium, driven by solute diffusion. The evolution of the gas results from the withdrawal of the liquid at a constant rate. The model addresses two stages before the onset of bulk gas flow, nucleation and gas phase growth. We assume negligible gradients due to gravity or viscous forces, thus the critical gas saturation, which signals the onset of bulk gas flow, is only a function of the nucleation fraction. We show that the important quantities characterizing the process, such as the fraction of pores that host activated sites, the deviation from thermodynamic equilibrium, the maximum supersaturation in the system and the critical gas saturation depend crucially on the nucleation characteristics of the medium.
Experiments on Fluid Flow and Heat Transfer in a Packed Channel Between Two Parallel Grooved Plates
Authors: Du J. H. , Ma B. , Wu W. , Hu X. J. , Wang B. X. 
Published: November 2021

Abstract
Experiments on fluid flow and heat transfer in a glass bead packed channel between two parallel grooved plates were conducted. The effects of the grooves on the surface of the heated plate upon the flow resistance and heat transfer were investigated. The results indicated that the grooves on the plate surface change the contact condition of the packed beads to the wall and increase the wall effect of the packed channels. Its direct consequence is to lower the flow resistance. The film heat transfer coefficient on the wall may be increased or rebated. It is demonstrated that a proper combination of packed beads and grooves can lead to the optimum performance of heat transfer for a specific configuration.
Heat Transfer of Slug Air-Water Flow in a Slightly Upward Inclined Tube
Authors: Kim Jae-yong , Trimble Steve , Ghajar Afshin J. 
Published: November 2021

Abstract
This paper presents a preliminary study on the heat transfer in slug air-water flow in a slightly upward inclined tube, which is a widely appeared pattern in the inclined two-phase flow regime. Local heat transfer coefficients and flow parameters have been measured for slug air-water flow in a pipe [1.097 in (2.79 cm) I.D. and L/D = 100] at slightly upward inclination angles of 2° and 5°. The heat transfer data with slug air-water flow pattern were measured under a uniform wall heat flux boundary condition. The change on the heat transfer with inclination angle compared to the horizontal case is discussed in terms of the change in the overall heat transfer coefficient with respect to the superficial gas and liquid Reynolds numbers. For these data, the superficial Reynolds number ranged from about 3700 to 28000 for the water and from about 540 to 6500 for the air. The results indicate that there is an increase in the heat transfer with only slight increases in the inclination angle. However, the amount of increase is strongly dependent on the magnitudes of superficial liquid and gas Reynolds numbers.