bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Surface Profile in Friction Stir Welding Using Coupled Eulerian and Lagrangian Method
Authors: Das Debtanay , Bag Swarup , Pal Sukhomay , Amin M. Ruhul 
Published: February 2021

Abstract
Friction stir welding (FSW) is widely accepted by industry because of multiple advantages such as low-temperature process, green technology, and capable of producing good quality weld joints. Extensive research has been conducted to understand the physical process and material flow during FSW. The published works mainly discussed the effects of various process parameters on temperature distribution and microstructure formation. There are few works on the prediction of defect formation from a physics-based model. However, these models ignore chip formation or surface morphology and material loss during the FSW process. In the present work, a fully coupled 3D thermo-mechanical model is developed to predict the chip formation and surface morphology during welding. The effects of various process parameters on surface morphology are also studied using the current model. Coupled Eulerian-Lagrangian (CEL) technique is used to model the FSW process using a commercial software ABAQUS. The model is validated by comparing the results in published literature. The current model is capable of predicting the material flow out of the workpiece and thus enables the visualization of the chip formation. The developed model can extensively be used to predict the surface quality of the friction stir welded joints.
Ten Years of Positive Feedback on Project-Based Learning From First-Year Engineering Students’ Perspective
Authors: Alves Anabela C. , Moreira Francisco , Leão Celina P. , Fernandes Sandra 
Published: February 2021

Abstract
Project-Based Learning (PBL) is an active student-centered learning methodology. Several schools (of varying degrees of education) have implemented, in different ways, PBL, having as common strands that the student learns in teams, and being challenged in the context of a case-scenario. In Portugal, a PBL methodology has been implemented, in the first year of an Industrial Engineering and Management (IEM) program, for more than 15 years. This represents a total number above 700 students of IEM enrolled in PBL during the reported timeframe. A continuous improvement process of the PBL activities was relentlessly pursued during such period. Grounded on end-of-term on-line PBL process satisfaction questionnaires, as well as on results of each PBL edition final workshops, this paper studies and reports on a number of such achievements and shortcomings. Thus, this paper presents the analysis of the results of ten academic years of PBL evaluation process, grounded on the compiled results obtained from 2009/10 to 2019/20. Also, a synthesis of the effective findings (either positive or negative), systematically pointed out by the students, will be presented. Altogether, the PBL implementation in the IEM program has been very positive for students and teachers and worth for others to follow.
Dynamic Simulation and Ground Testing of the Autonomous Vertical Air-Launch Sled Concept
Authors: Lee Peter , Sarigul-Klijn Nesrin 
Published: February 2021

Abstract
A unique towed air-launch concept called the vertical air-launch sled is studied using a 1/32nd scale vehicle. The sled allows a launch vehicle carried by it to be towed to an altitude by a mother aircraft using a standard towline. The focus was to design and test autonomous tow taxi and takeoff phase of flight using simulations and flight tests. In order to study the scaling validity, experimental flight test data was compared to the theoretically predicted dynamic response of the scaled system, as well as compared to a theoretically predicted dynamic response of the full-scale system. The towing aircraft is a 1/11th scale T-28 remotely piloted aircraft. Lateral stability, runway centerline following ability as well as tautness of the tow line are studied as measures of performance of the autonomous system designed. Test results are reported showing that the tow aircraft was able to tow the vehicle along the correct path. It is identified that the rudder servos were saturated in adjusting the trajectory and future flight tests will include implementing front wheel steering into the system to alleviate the rudder servos saturation. Duration of the flight tests will be increased to better evaluate the automatic controller.
Vibration Suppression for Large-Scale Flexible Structures Using Deep Reinforcement Learning Based on Cable-Driven Parallel Robots
Authors: Sun Haining , Tang Xiaoqiang , Wei Jinhao 
Published: February 2021

Abstract
Specific satellites with ultra-long wings play a crucial role in many fields. However, external disturbance and self-rotation could result in undesired vibrations of flexible wings, which affects the normal operation of the satellites. In severe cases, the satellites will be damaged. Therefore, it is imperative to conduct vibration suppression for these flexible structures. Utilizing deep reinforcement learning (DRL), an active control scheme is presented in this paper to rapidly suppress the vibration of flexible structures with quite small controllable force based on a cable-driven parallel robot (CDPR). To verify the controller’s effectiveness, three groups of simulation with different initial disturbance are implemented. Besides, to enhance the contrast, a passive pre-tightening scheme is also tested. First, the dynamic model of the CDPR that is comprised of four cables and a flexible structure is established using the finite element method. Then, the dynamic behavior of the model under the controllable cable force is analyzed by Newmark-ß method. Furthermore, the agent of DRL is trained by the deep deterministic policy gradient algorithm (DDPG). Finally, the control scheme is conducted on Simulink environment to evaluate its performance, and the results are satisfactory, which validates the controller’s ability to suppress vibrations.
Enhancement in Forced Convection by a Two Stage Corona Wind Generator
Authors: Mazumder A. K. M. Monayem H. 
Published: February 2021

Abstract
In this study, forced convection enhancement in a square channel by a two stage electrohydrodynamic (EHD) gas pump is numerically analyzed. This study is implemented for a two stage EHD gas pump with three emitting electrode configurations: 8, 24, and 56 respectively to seek their effectiveness in the enhancement of forced convection and pumping power requirement. The EHD gas pump is evaluated for a wide range of operating voltages starting from 20 kV up to 28 kV. The influence of electric field on the flow and temperature fields is also examined for a wide range of Reynolds numbers. The three-dimensional governing equations for the flow and temperature fields are solved using the finite volume method. The Reynolds numbers (Re) considered in this study varies in a range between 100 and 2000. At Re = 100, a maximum increase of 42% in the average Nusselt number is achieved with an applied voltage of 28 kV. The overall effectiveness of the EHD gas pump in heat transfer enhancement is evaluated by the thermal hydraulic performance parameter, (Nu/Nu0)/(f/f0), which is always greater than unity. These results disclose that EHD technique has a great potential for many engineering applications, particularly for thermal management.
Research on Flow and Heat Transfer Characteristics of Multiple Impinging Jets on a Moving Conveyor Belt
Authors: Liu Rui , Sun Yu , Ni Jun 
Published: February 2021

Abstract
Turbulent impinging jets at three different jet nozzle forms were numerically analyzed using the SIMPLE algorithm and k-epsilon turbulent model to investigate the flow field and heat transfer characteristics. The food placed upon a moving conveyor belt cooled by series of impinging jets under a specific condition. Three semi-confined domains with different jet nozzles were established, thereby with slot, rectangular, and funnel-shaped nozzles, respectively. Based on computational fluid dynamic (CFD) calculations, distributions of the temperature and wind velocity at four critical cross-sections of domains were compared. The results reveal that the freezing rate of foods mainly relates to temperature and wind velocity. For three semi-confined domains, the impinging jet with slot nozzles produces higher exit wind velocity, lower center temperature, and a better mass flow uniformity than others, which could better improve the heat transfer performance, and could increase the freezing rate of foods.
Finite Element Study of the Effect of Load Sequence on the Fretting Wear
Authors: Dhaka Pankaj , Prakash Raghu V. 
Published: February 2021

Abstract
Understanding the effect of load sequence is important in the context of a blade-disc dovetail joint in an aero-engine and many other such applications where, the mating surfaces undergo fretting wear under variable slip amplitude loading conditions. In the present work, a two-dimensional finite element analysis is carried out for a cylinder-on-plate configuration. The cylinder is modeled as deformable whereas the plate is modelled as rigid. An incremental wear modelling algorithm is used to model the wear of cylindrical pad while the plate is assumed as un-worn. This simulates a practical scenario where, generally one of the mating surfaces is sufficiently hardened or an interfacial harder/sacrificial element is inserted to restrict the wear to only one of the surfaces. A Fortran-based ABAQUS® subroutine UMESHMOTION is used to simulate the wear profile for the cylinder. A constant extrapolation technique is used to simulate 18000 cycles of fretting. The finite element analysis results are validated with the analytical solutions and literature data. The fretting wear modelling is carried out for two different slip amplitudes viz., 25 μm and 150 μm, to simulate the low and high slip amplitude loading respectively. Two blocks of alternate low and high slip amplitudes are applied to understand the influence of load sequence. Important contact parameters viz., contact pressure, contact stresses and contact slip are extracted. A comparison is made between the low-high and high-low load sequence based on the contact tractions and worn out profiles.
Human-Machine Teaming: A Movement-Focused Approach
Authors: Fukuda Shuichi 
Published: February 2021

Abstract
To cope with today’s frequent, extensive and unpredictable changes, humans and machines need to work together on the same team. Team organization and management called for now is to develop a truly adaptable network without any constraints. Movement works as a communication tool for the human-machine team, and in addition, movement will bring emotional harmonization between humans and machines and psychological satisfaction and happiness to humans. Although instinct has been neglected in traditional engineering, it plays an important role to coordinate many body parts and balance our bodies, and for interactive holistic perception and for making better decisions. Emerging reservoir computing will produce extremely small devices so they will work together on us and enable us to interact directly with the outside world through our bodies. And such human-machine team will motivate us to challenge rehabilitation and healthcare, which, therefore, will become a kind of a game, But to achieve this goal, a holistic and quantitative performance indicator is necessary. Euclidean Space approach requires orthonormality and units. But to manage movements, we must be free from these constraints. Therefore, Mahalanobis Distance-Pattern Approach, which is non-Euclidean, is proposed.
The Topology Within Recirculating Flow in the Atomic Layer Deposition Thin Film Process
Authors: Coetzee Rigardt Alfred Maarten , Hoenselaar Damon James , Bhamjee Muaaz , Jen Tien-Chien 
Published: February 2021

Abstract
Nanotechnology fabrication has become a popular field in the development of advanced and cutting-edge technologies. Deposition processes are industrialized to achieve nano-thin films with absolute control over the film thickness, conformal and uniform film growth over complex structures, and minimal to no defects or pinholes. Atomic layer deposition (ALD) has revealed itself as a possible candidate to achieve these requirements. However, the in-depth understanding of the physical and chemical formation of the thin film is still unfamiliar to reactor designers, engineers and scientists. For the purposes of this study, the interest involves the mechanistic factors of geometry influences, fluid flow, and mass transportation on the heterogeneous chemical reaction process. Through an industrial ALD process recipe, the transitional and recirculation phenomena observed in the Atomic Layer Deposition (ALD) thin film process are seen to exert a significant influence on the effective formation and growth of the thin film on the substrate. Topological fluid dynamics are used to analyze the two-dimensional numerical simulations of the backward-facing step (BFS) phenomena and the recirculation flow patterns typically found within a horizontal ALD reactor. Focus is placed on investigating the saddle points in the resulting vortex shedding, eddy distortion and recirculation due to the BFS phenomena. The topological analysis is conducted for symmetrical step heights of 7.5mm and 10 mm respectively. Findings revealed close similarities to experimental studies.
Digital Image Correlation Method in Measuring the Out of Plane Displacement: A Case Study on an Artificial Intervertebral Disc
Authors: Raheem Hassan M. , Rochefort Willie “Skip” E. , Bay Brian K. 
Published: February 2021

Abstract
We have developed a simple, low-cost, and innovative design — known as a “disc emulator” to mimic the mechanical response of a motion segment (vertebra - intervertebral disc-vertebra) of the human spinal column under axial compression loads. The disc emulator consists of upper and lower components that mimic the human vertebrae and a middle component that represents the annulus fibrosus (AF). This study aims to investigate the effects of changing the stiffness of artificial annulus fibrosus of the disc emulator on the bulging measurements while performing compression tests on the disc emulator. A non-contact measurement — digital image correlation (DIC) — was used for the bulging measurements. The results show that the bulging at the posterior region for the discs without nucleus pulposus (NP) bulged inwards, but the bulging at the posterolateral region was outwards, which accords with the reported behavior of the human disc, for the disc without and with NP regardless of the stiffness of the discs. Changing the stiffness of the artificial annulus fibrosus (AAF) alters the bulging magnitudes in the disc, which shows similar responses with respect to the available data on the human disc. The emulator provides a convenient experimental platform for evaluating normal and pathological disc states and assessing the biomechanics of potential therapeutic interventions.
Validation of a Physics Based Three Phonon Scattering Algorithm Implemented in the Statistical Phonon Transport Model
Authors: Medlar Michael P. , Hensel Edward C. 
Published: February 2021

Abstract
Three phonon scattering is the primary mechanism by which phonon transport is impeded in insulating and semiconducting bulk materials. Accurate computational modeling of this scattering mechanism is required for high fidelity simulations of thermal transport across the ballistic (quantum mechanics) to Fourier (continuum mechanics) range of behavior. Traditional Monte Carlo simulations of phonon transport use a scaling factor such that each scattering event is considered representative of a large number of phonons, often on the order of 104 physical phonons per simulated event. The ability to account for every phonon scattering event is desirable to enhance model fidelity. A physics-based model using time dependent perturbation theory (Fermi’s Golden Rule) is implemented to compute three phonon scattering rates for each permissible phonon interaction subject to selection rules. The strength of the interaction is based on use of a Gruneisen-like parameter. Both Type I and Type II scattering rates are computed for the allowable interactions that conserve energy and momentum (up to the addition of a reciprocal lattice vector) on a given discretization of momentum space. All of the phonons in the computational domain are represented and phonon populations are updated in momentum space and real space based on the computed number of phonons involved in given scattering events. The computational algorithm is tested in an adiabatic single cell of silicon of dimension 100 × 100 × 100 nm at a nominal temperature of 500 Kelvin containing approximately 108 fully anisotropic phonons. The results indicate that phonon populations return to equilibrium if artificially displaced from that condition. Two approaches are introduced to model the relaxation time of phonon states: the single mode relaxation time (SMRT) which is consistent with the underlying assumptions for previously reported theoretical estimates, and the multi model relaxation time (MMRT) which is more consistent with in-situ conditions. The trends meet physical expectations and are comparable to other literature results. In addition, an estimate of error associated with the relaxation times is presented using the statistical nature of the model. The three phonon scattering model presented provides a high fidelity representation of this physical process that improves the computational prediction of anisotropic phonon transport in the statistical phonon transport model.
Construction and Performance Analysis of a Two-Stage Traveling-Wave Thermo-Acoustic Generator
Authors: Shamase H. S. , Tartibu L. K. 
Published: February 2021

Abstract
Thermo-acoustic technology offers the possibility to convert heat energy into a sound-wave that can potentially be used to generate electricity through a linear alternator. The construction of a two-stage traveling-wave thermo-acoustic generator is described in this paper. The potential of conversion of heat into electricity has been investigated experimentally. The effect of the geometrical configurations of the thermo-acoustic system on its performance has been analyzed. The two thermo-acoustic engine cores were tested separately and subsequently combined to build a two-stage system. Two different configurations of engine cores have been considered namely series and parallel configuration. Hence, the effect of the orientation of the engine core has been investigated to get an insight into its effect on the output of the device. Parallel arrangement was found to be the most efficient configuration. An onset time of 3.15 minutes was recorded for the device to generate a sound wave. This system has achieved 125.7 dB corresponding to an output voltage of 486 mV. This study guides the development of more efficient electricity generators using thermo-acoustic technology.
Virtual Commissioning for Advanced Manufacturing Using Digital Tools
Authors: Guerra-Zubiaga David , Kamperman Kevin , Aw Mohamed 
Published: February 2021

Abstract
Following the Industry 4.0 paradigm with the rise of smart factories, there is a growing need in exploring digital manufacturing tools compatible with Industrial Internet of Things (IIoT) functionalities. This paper discusses the concept of Virtual Commissioning (VC) including applications in present and near-future advanced automation and production. Specifically, global trends towards Industry 4.0 and virtual manufacturing processes are explored in addition to how and why these emerging technologies could be applied. Furthermore, the advantages of VC processes are contrasted to Traditional Physical Commissioning (TPC) to highlight the evolution of Product Lifecycle Management (PLM) software and the optimization of manufacturing processes since the turn of the century. This research aims to use state-of-the-art PLM software to replicate a physical prototype in near-perfect functionality to demonstrate the effectiveness of VC in an industrial setting. Developing a methodology for this research, the analysis is followed by a case study involving a Mini Festo Pick-and-Place (P&P) unit simulated in Siemens Tecnomatix Process Simulate and controlled via ladder logic executed in Totally Integrated Automation (TIA) Portal. As expected, the results of this case study validate the potential for optimized contemporary manufacturing solutions in which higher-quality goods are reliably produced with minimal delays at all-time low principal investments through the use of VC tools.
Improved Process Control Using Hybrid Industrial Internet of Things Network Topology
Authors: Guerra-Zubiaga David , Strickland Jay , Kamperman Kevin , McHale Ryan , Nasajpour-Esfahani Navid 
Published: February 2021

Abstract
Industry 4.0 is an important manufacturing paradigm driving research and the enhancement of Industrial Internet of Things (IIoT) technologies on a global scale. The expanding capabilities of IIoT technologies has risen to meet customer demand for intelligent, interconnected devices. Legacy Programmable Logic Controllers (PLCs) remain the industry standard for manufacturing and process control even though Free and Open Source Software (FOSS) has emerged as a feature-rich market alternative. This paper compares and contrasts traditional closed systems and new FOSS in the context of Industry 4.0 trends through a literature review and reports on the resultant capabilities of their synthesis. A methodology for linking these previously independent systems through IIoT is presented via case study using a mobile autonomous robot to interact automatically with a custom process control training bench (PCTB) in a scenario analogous to a mobile delivery robot. The novelty of this research is the synthesis of traditional closed and open systems across a new class of smart device, the semi-proprietary IIoT network bridge. Hybridization, it is concluded, presents the most advantageous features of both proprietary systems and FOSS without many of the trade-offs typically encountered when employing technologies under either paradigm.
Incorporating 3D Printing to Bridge Two Introductory Courses in Mechanical Engineering
Authors: Denizhan Onur , Chew Meng-Sang 
Published: February 2021

Abstract
A course in Computer Graphics using SolidWorks™ is one of the very first courses that a Mechanical Engineering major would take within the department at Lehigh University. In this course, students learn the basics of engineering graphics with a view towards engineering design. Such a course gives students an overall view of not just the mechanics of creating engineering drawings using SolidWorks, but also one of understanding the consequences of their drawings as they affect tolerances, material selection, fabrication processes as well as the viability of their designs. The very next introductory mechanical engineering course is a laboratory dealing with engineering measurements, data acquisition and testing. This article reports on the use of a 3-D printing exercise to bridge these two somewhat very different courses with different objectives, thereby giving students an early start into understanding the process of design; from a concept to its design and fabrication, and finally, testing and analysis of data. Moreover, it gives a fundamental understanding of the use of 3-D printing that many students would end up using for their Senior Design course in their senior year.