bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Comparisons of Heat Transfer From a Single Jet Emanating From a Slot Nozzle Impinging on an Isothermal Plate
Authors: Tibabisco Cristian , Vargas-Díaz Salvador , Salamah Samir A.
Published: January 2020

Impingement jets are used in different cooling applications where it is required to remove large amounts of heat. Heat transfer in the stagnation point for a single jet impinging on an isothermal plate is investigated with four turbulence models. Two models are RANS (Reynolds Average Navier-Stokes): Transition SST and Transition κ–κl–ω. The other two models are URANS (Unsteady Reynolds Average Navier-Stokes): SAS and DES-SST. This paper explores the best turbulence model for thermal design and cooling purposes. Results are validated with experimental data reported by Gardon & Akfirat. These four turbulence models are available in the commercial CFD software package ANSYS FLUENT 18.1. Special attention is paid to the heat transfer in the impingement region through evaluation of Nusselt number in the stagnation point. Different dimensionless nozzle-to-plate distances are considered in this work (z/b = 14 to z/b = 40), and two different Reynolds numbers are used Re = 11,000 y Re = 22,000. Three turbulence models are within reasonable accuracy (10%) of the experimental data, but some turbulence models have problems with convergence and grid independence, especially the URANS models. Based on these results, the best turbulence model for applications in heating and cooling systems where impingement heat transfer is critical is the Transition κ–κl–ω.
Enhancing the Frictional Behaviour of H-BN Reinforced Nanocomposites Through Laser Shock Peening
Authors: Joel J. , Anthony Xavior M.
Published: January 2020

In this research work, LM6 Aluminum alloy based metal matrix composites reinforced with varying amounts (0.2, 0.4, 0.6 and 0.8 wt%) of boron nitride (BN) having 10 to 30 nanometers average size were developed by using powder metallurgy and squeeze casting routes. The mechanical and tribological properties are analyzed for the samples developed through the two different routes and the influence of the process on the properties is discussed. Thus developed nano composite is studied for the effect of weight percentage addition of nano H-BN particle on the bulk and surface properties. Mechanical testing and advanced characterization methods are used to study the effect of the nano H-BN addition to the matrix material and to evaluate the composite for its suitability as a potential friction material used in strategic sectors. It has been inferred that the presence of nano H-BN have improved the bulk and surface properties. Further, it has been established that the powder metallurgy route has some favorable results when compared to squeeze casting in terms of certain properties. Thus fabricated composites were subjected to laser shock peening process to study its impact on the surface and wear characteristics. The 0.6 wt% H-BN reinforced composites fabricated separately by Powder metallurgy and Squeeze casting method are exposed to laser shock peening process and it was inferred that there is a significant improvement on the surface and wear properties when compared to normal specimen.
Ultrasonic Characterization of the Elastic Constants in an Aging Ti-6Al-4V ELI Alloy
Authors: Carreon Hector
Published: January 2020

In this paper, we report the experimental data of the elastic properties of the young and shear modulus based on the variation in the ultrasonic velocity parameter during the microstructural evolution in a Ti-6Al-4V alloy with two varying microstructures, bimodal and acicular respectively. The two different initial microstructures, were treated thermally by aging at 515°C, 545°C and 575°C at different times from 1 min to 576hr to induce a precipitation process. Ultrasonic measurements of shear and longitudinal wave velocities, scanning electron microscopy (SEM) image processing, optical microscopy (OM) and microhardness were performed, establishing a direct correlation with the measurements of the ultrasonic velocity and the elastic properties developed during the thermal treatment of the artificial aging. The results of the ultrasonic velocity show a very clear trend as the aging time progresses, which is affected by precipitation of Ti3Al particles inside the α phase. In this way, we can know, in a fast and efficient way, the elastic properties developed during the heat treatment of aging at long times, since the presence of these precipitates hardens the material microstructure affecting the final mechanical properties.
Verification of CFD Prediction Accuracy of Flow Turbulence Induced Vibration Loadings Around a Pipe Bend
Authors: Hu Xidong , Qian Shaoxiang , Matsuura Kota , Kataoka Shunji
Published: January 2020

Bends widely used in process piping systems can cause strong pressure fluctuations on pipe wall for a high-velocity flow, and hence, flow induced vibration (FIV) of piping occurs. Currently, the FIV assessment is made primarily based on the guideline published by Energy Institute. However, it is based on very conservative assumptions, and thus, results in excessive design of piping systems. The coupling analysis of CFD/FEA (Computational Fluid Dynamics/Finite Element Analysis) is expected to be a useful approach for more proper FIV assessment. The present study mainly aims at verifying CFD prediction accuracy of wall pressure fluctuations or FIV loadings around a pipe bend.

In CFD benchmark study, large eddy simulations (LES) with dynamic Smagorinsky model (DSM) were performed for a 90° mitred bend used in the experiments in literature, under two different flow velocity conditions. The benchmark simulation results show that the power spectral density (PSD) of the LES-predicted wall pressure fluctuations at the sampling locations is near to the experimental results with moderate conservativeness desirable for engineering applications. Also, the LES-predicted peak frequencies are close to the experimental data. Therefore, it is suggested that the applied numerical approaches be applicable to predict the FIV loadings with moderately high accuracy for engineering applications.
Enhancing the Cell Viability in High Throughput Deterministic Lateral Displacement Separation of Circulating Tumor Cells
Authors: Aghilinejad Arian , Landry Christopher , Cha George , Chen Xiaolin
Published: January 2020

Cancer is among a major health concerns all over the world. Cancer metastasis, which defines as the migration of malignant cells from original sites to distant organs, is the main reason of death due to cancer and there is growing evidence that Circulating Tumor Cells (CTCs) are responsible for initiating the metastasis. Due to the importance of these bioparticles in biotechnology and medicine, there is a growing interest to study and separate them through different techniques especially microfluidic label-free technologies. One such technology, termed Deterministic Lateral Displacement (DLD) has recently shown promising abilities to separate cells and particles of different sizes. However, DLD is a separation method that takes advantages of the predictable flow laminae of low Reynolds number (Re) fluid flow. In order to achieve higher device throughput, effects of higher Reynolds number flow on DLD device should be studied. Additionally, the higher flow rates would apply higher forces and shear stresses on the cells which threaten the cell’s viability. In this study, employing numerical simulation, the effect of high Re number on DLD device for separating cancer cells has been investigated. Specifically, we conducted force analysis and by focusing on the downstream gap distance between the posts, we improved the device which results in less cell deformation. Our developed numerical model and presented results lay the groundwork for design and fabrication of high-throughput DLD microchips for enhanced separation of CTCs.
Using EMG Signals to Remotely Control a 3D Industrial Robotic Arm
Authors: Batayneh Wafa , Bataineh Ahmad , Abandeh Samer , Al-Jarrah Mohammad , Banisaeed Mohammad , alzo’ubei Bara’ah
Published: January 2020

In this paper, a muscle gesture computer Interface (MGCI) system for robot navigation Control employing a commercial wearable MYO gesture Control armband is proposed. the motion and gesture control device from Thalamic Labs. The software interface is developed using LabVIEW and Visual Studio C++. The hardware Interface between the Thalamic lab’s MYO armband and the robotic arm has been implemented using a National Instruments My RIO, which provides real time EMG data needed. This system allows the user to control a three Degrees of freedom robotic arm remotely by his/her Intuitive motion by Combining the real time Electromyography (EMG) signal and inertial measurement unit (IMU) signals. Computer simulations and experiments are developed to evaluate the feasibility of the proposed System. This system will allow a person to wear this/her armband and move his/her hand and the robotic arm will imitate the motion of his/her hand. The armband can pick up the EMG signals of the person’s hand muscles, which is a time varying noisy signal, and then process this MYO EMG signals using LabVIEW and make classification of this signal in order to evaluate the angles which are used as feedback to servo motors needed to move the robotic arm.

A simulation study of the system showed very good results. Tests show that the robotic arm can imitates the arm motion at an acceptable rate and with very good accuracy.
Design, Development and Implementation of Vibratory Mechanisms to Be Utilized in Dynamics and Vibrations Courses
Authors: Woldemariam Yoseph , Garcia Martin , Utschig Tris , Tekes Ayse
Published: January 2020

There is still a demand for novel laboratory equipment designs that are to be utilized in undergraduate level machine dynamics, mechanical vibrations, control theory and their related labs. Since the turn-key systems preferred in most undergraduate labs are expensive and require wide lab space, 3D printed portable, small scale and cost-effective vibrational lab equipment are designed to study the fundamentals of free and forced vibrations. Four laboratory equipment designs are proposed in this study to demonstrate the fundamentals of vibration such as free vibration, forced vibration, modeling, base excitation and vibration isolation. The first device is a vibration isolator and resonator mechanism incorporating large deflecting fixed-free flexible links and composed of primary and secondary masses and a linear actuator, the second mechanism is a compliant parallel arm consisted of flexible beams, mass and a support, third mechanism is a translational vibratory mechanism comprised of slider carts, 3D printed springs, rods and bearings and the final mechanism is the model of driver seat consisted of DC motor, driver and driven wheels and a mass. Main parts of each apparatus are built by 3D printing using either PLA or PETG filament. Learning outcomes and the methods of implementing each device to the course and their associated laboratories are provided.
A Level Set Based Geometry Handling Approach Used in the Immersed Boundary Methods for Fluid-Structure Interaction
Authors: Yao Guangfa
Published: January 2020

Immersed boundary methods have gained increasing attention in modeling fluid-solid body interaction using non-body conforming computational fluid dynamics, due to their robustness and simplicity. They usually do this by adding a body force term in the momentum equation. The magnitude and direction of this body force ensure that the boundary condition on the solid-fluid interface is satisfied without invoking complicated body-conforming numerical methods to impose the boundary condition. The body force is usually calculated and imposed using some interpolation or extrapolation around the solid-fluid interface. It can also be calculated based on the solid volume fraction in the cells around the solid-fluid interface. Therefore, it is critical to have a robust method to represent or track arbitrary solid bodies immersed in a fluid field and facilitate the needed interpolation, extrapolation, or calculation of solid volume fraction. To that end, the level set method has been used as a robust method to represent and track arbitrary solid bodies in a fluid field. In the presented paper, the level set based approaches used to handle arbitrary solid bodies in a fluid field are reviewed, and a new higher order method is presented to resolve the solid-fluid interface using the given level sets at each grid point.
Experimental Investigation of Water Emulsion Fuel Stability
Authors: Singh Gurjap , Lopes Elio , Hentges Nicholas , Ratner Albert
Published: January 2020

The combustion of liquid fuels emulsified with water have long generated interest in the internal combustion engine research community. Typically, these fuels consist of small quantities of water emulsified with ultrasonification or other mechanical methods into a pure or multicomponent hydrocarbon fuel. These emulsion fuels promise significant advantages over base liquid fuels, such as better fuel economy, colder combustion temperatures, less NOx emissions, and so on. However, a significant practical disadvantage of these fuels is that they are prone to phase separation after they have been prepared. Till date, an objective but economical method of identifying the various degrees of phase separation has not been identified. Present research presents such a method and shows its utilization in analyzing the stability of water and hydrocarbon fuel emulsions over time without the addition of chemical stabilizers. It is expected that present research will pave the way in establishing this method to study the stability of other specialized multicomponent fluids.
Nonlinear Damping in Large-Amplitude Vibrations of Viscoelastic Plates
Authors: Amabili Marco , Balasubramanian Prabakaran , Ferrari Giovanni
Published: January 2020

Damping is largely increasing with the vibration amplitude during nonlinear vibrations of rectangular plates. At the same time, soft materials present an increase of their stiffness with the vibration frequency. These two phenomena appear together and are both explained in the framework of the viscoelasticity. While the literature on nonlinear vibrations of plates is very large, these aspects are rarely addressed. The present study uses the fractional solid model to describe the viscoelastic material behaviour. This allows to capture at the same time (i) the increase in the storage modulus with the vibration frequency and (ii) the frequency-dependent nonlinear damping in nonlinear vibrations of rectangular plates. The solution of the nonlinear vibration problems is obtained through Lagrange equations by deriving the potential energy of the plate and the dissipated energy, both geometrically nonlinear and frequency-dependent. The model is then applied to a silicone rubber rectangular plate tested experimentally. The plate was glued to a metal frame and harmonically excited by stepped sine testing at different force levels and the vibration response was measured by a laser Doppler vibrometer. The comparison of numerical and experimental results was satisfactorily carried out for: (i) nonlinear vibration responses in the frequency and time domain at different excitation levels, (ii) dissipated energy versus excitation frequency and excitation force, (iii) storage energy and (iv) loss factor, which is particularly interesting to evaluate the plate dissipation versus frequency at different excitation levels. Finally, the linear and nonlinear damping terms are compared.
Six-Sigma Challenges in Services With Human-Based Data: An Investigative Case Study for Clients’ Satisfaction in Gas Company
Authors: Pourgol-Mohamad Mohammad
Published: January 2020

Improvement of business processes, increasing customer satisfaction, and reducing organizational costs are important issues that institutions deal with. In this context, six sigma methodology has been considered as a systematic approach to achieve these goals by many organizations. In recent years, non-industrial sectors, where human data are involved, have also applied this technique to improve their processes quality. For application of six sigma procedure for non-industrial issues, there are several challenges that are not encountered in the conventional implementation of Six Sigma procedure. Most of these challenges are experienced on gathering the human (operators, experts) expressed data required for the six sigma projects on the phase of measurement and analysis. The challenges identification and analysis give the ability to address them and provide practical solutions. In this study, in addition to different stages of the Six Sigma methodology, its implementation has been investigated in the non-industrial sector in the DMAIC phases. The challenges dealt with in this research include the impact of external factors on human data, limitations in the design of experiments for human data, qualitative data and discrete data as well as one-sided data. Also, considering a case study on the implementation of six sigma methodology to enhance customer satisfaction in an East Azerbaijan Gas company, strategies are presented for overcoming these obstacles.
Research on the Performance of Metal Connectors of Injection-Molded Long-Glass-Fiber Reinforced Thermoplastic Composite Wheel
Authors: Zhang Yue , Shan Yingchun , Liu Xiandong , He Tian , Wang Xiaoran , Dang Bin , Zeng Xianyu
Published: January 2020

In order to ensure stiffness and wear resistance of joint surface, injection-molded long-glass-fiber reinforced thermoplastic (IMLGFT) composite wheel is installed on hub or metal table of wheel test bench by fastening bolts through metal connectors. Firstly, the structure of composite wheels with metal connectors is simplified. Then the strength analysis is carried out to test the two kinds of simplified models by using superposed beams theory and ABAQUS finite element software respectively based on the wheel bending fatigue test. In addition, the stress conditions of the wheel using the metal insert or the metal clamp plate are compared. The results show that two structural forms of metal connectors have protective effect on the composite parts of the wheel, and the protective effect of metal clamp plate connector on composite parts is better than that of metal insert connector. The research results provide guidance for the metal connector design of IMLGFT composite wheel.
A Model Science-Based Learning STEM Program
Authors: Cieslinski Benjamin , Gharib Mohamed , Creel Brady , Katbeh Tala
Published: January 2020

In this paper, a model STEM program called Engineering Heroes: Qatar Special Investigators (QSI), aimed to familiarize young students with science and engineering in real life applications, is presented. The program theme is about forensic science and technology, which included science and engineering activities with hands-on projects to challenge students’ science and critical thinking skills. Throughout the program, students learned about forensic science as an application of science, engineering and technology to collect, preserve, and analyze evidence to be used in the course of a legal investigation. Participants learned the history of forensic analysis and how it evolved into today’s specialized career field. Forensic specialists include backgrounds in chemistry, physics, biology, toxicology, chemical and electrical engineering. Topics included in the program were a study of toxicology and chemical analysis, assays to determine drug contents, fingerprint development, environmental contamination, chromatography in forgery, presumptive vs. confirmatory testing, scanning electron microscopy, infrared analysis, and evidence handling techniques. The details of the program are presented, including the contents, preparation, materials used, case studies, and final crime scene investigation, which featured the learning outcomes.
Ambient Temperature Effect on Performance of a Lithium-Ion Polymer Battery Cell for 12-Voltage Applications
Authors: Liu Yiqun , Liao Y. Gene , Lai Ming-Chia
Published: January 2020

Operating temperature has a significant impact on the performance, safety, and cycle lifetime of the lithium-ion batteries. The operating temperature of a battery is the result of the ambient temperature augmented by the heat generated by the battery. This paper presents the empirical investigation of the effect of ambient temperature on the performance of a Lithium-Nickel-Manganese-Cobalt-Oxide based cell with 3.6V nominal voltage and 20Ah capacity. The experiments are carried out in an environment chamber using five controlled temperatures at −20°C, −10°C, 0°C, 20°C, and 50°C, as the ambient temperatures. In each controlled temperature test, a constant current (10A, 20A, and 40A) continuously discharge the cell to a cut-off 2.5V. The cell discharging voltages and usable capacities are the battery performance indicators. The experimental tests show that discharging voltage at 50% DOD and the total discharging time to reach 2.5V (usable capacity) increase as the ambient temperature increases. The modeling and simulation of a battery cell temperature model is built in the Simulink platform. The correlations show that simulated and experimental discharging curves match well in the 0–80% DOD range and the discrepancy is under 7%. The developed simulation model could provide thermal management guidelines for lithium-ion polymer battery applications in 12 voltage SLI, start-stop, and 48 voltage mild hybrid electric vehicles.
Single Point Incremental Forming of Large Sheet Metal Components
Authors: Schieck Frank , Mauermann Reinhard , Weise Dieter , Demmler Matthias
Published: January 2020

The production of complex, large-scale cladding parts made of metal in small quantities for a wide range of applications in architecture, power generation, shipbuilding, but also rail vehicle construction, mobile work machines and, last but not least, automotive sector is a major challenge in terms of principled manufacturability, but also in terms of manufacturing costs. Appropriate components are often produced in small quantities by hand, whereby the reproducibility and achievable quality depend largely on the experience and craftsmanship of the employer.

The incremental forming using CNC-controlled machine tools or robots offers a good alternative for an efficient and reproducible production of sheet metal components with batch size one. There are already a large number of research work, studies and examples of applications worldwide regarding principled incremental forming strategies, process layout, FE simulation and optimization strategies.

The Fraunhofer IWU works with the claim of applied research, that is, to transfer results from basic research into an industrial application. This also applies to the field of incremental sheet metal forming. Especially in the area of large-scale, 3-dimensional components, there is a very great need on the part of the industry.

The paper provides an overview of current research results in the field of incremental forming of industrially relevant large-scale structures up to dimensions of approximately 4 × 2 meters, which are carried out in the single point process on a modified large milling machine. The topic of shape storage (molds), flexible clamping frames and heating equipment for temperature-supporting incremental forming of light metals is also addressed. The outlook identifies application and development potential aimed at both the further development of the technology and the associated equipment technology.
Mechanical Properties of Steel Printed on Ceramics
Authors: Allameh Seyed M. , Ortiz Rejon Miguel
Published: January 2020

Construction industry is about to embrace 3D printing as a viable technology for fabricating structures that are not physically or commercially impractical. These include curved components that could be embedded in buildings. On the other hand, whole house building by 3D printing has been attempted around the world using giant concrete printers. The main question is how to integrate steel rebars in concrete by 3D welding and still maintain the structural integrity and reliability of the conventional rebars. To accomplish the incorporation of rebars in concrete, steel must be welded within concrete. Heat dissipation rates may be different in different directions when the 3D molten weld pool solidifies, especially when the substrate is concrete. This may affect the strength of the material along and across the weld bead. To investigate this effect, it is important to study the mechanical properties of 3D welded steel in the directions of length, thickness and width. Experiments conducted in this study include the 3D welding of steel on concrete tiles by attaching the torch of a MIG welder to a meter-scale 3D printer carriage. The weld beads were then cross sections in directions along the weld bead, across the bead and perpendicular to the ceramic substrate. Dog-bone shaped micro-scale samples were extracted along those direction by CNC machining and EDM milling. The specimens were then mounted on the grippers of a hybrid micro-tester and tensile tests were carried out. The results of the tests are reported, and the implications of the findings in terms of the feasibility of 3D printing of steel reinforced concrete are discussed.
Combinatorial Investigation of Mechanical Properties of Biomimicked Composites
Authors: Allameh Seyed M. , Miller Roger , Almuzaini Abdullah
Published: January 2020

This study presents the preliminary results of in-situ tests conducted on structural biomimicked composites built by 3D printing. Construction industry is looking seriously into 3D printed structures that can be incorporated into the conventional buildings. Further refinement of materials and processing will lead to the 3D printing of buildings in future. The advantages afforded by 3D printing are unrivaled, creating unprecedented opportunities to express art, economics, environmentally friendly designs, lightweight schemes, among many others. To determine the reliability and suitability of structural composites for use in construction, it is important to test these in shapes, and geometries that are appropriate to 3D printing. Combinatorial materials research allows the fabrication and in-situ testing of composites made by mix and match of various materials. This study focuses on the characterization of mechanical behavior of biomimicked composites fabricated by a 3D printer. To accomplish this, a meter-sized 3D printer was equipped with material dispensers as well as load sensors. Composites were made of various construction materials, adhesive, and reinforcement and subsequently tested by the same printer. The results are presented, and the implications of findings are discussed on their impact on the construction industry.
Investigate the Potential Peak Energy Reduction of Integrated M-Cycle Evaporative Cooling With HVAC in Hot and Dry Climate
Authors: Almehmadi Fahad , Aljabr Ahmad
Published: January 2020

The purpose of the study is to investigate the potential energy saving of integrated M-Cycle evaporative cooling with HVAC. The model consists of three sub-systems which are thermal model of the typical house in Saudi Arabia, HVAC, and M-Cycle evaporative cooling. A thermal model of the typical house is performed to estimate the cooling load and then an integration between these sub-systems were built in MATLAB Simulink where the dynamic behavior of the whole system is examined. The house was simulated based on the actual hourly outdoor temperature and the physical properties of the house to estimate the cooling loads. To facilitate the simulation, the average hourly temperature is used. The results of the simulation show that energy consumption during peak hours can be reduced by up to 6%. It was found that the control system has a tremendous impact on controlling house temperature and cooling load. The impact of two different control strategies is investigated and their influence on house temperature and cooling loads are determined. It was found that PID control has advantage over On/Off control, in which the temperature in the space environment is kept uniform, and energy consumption is reduced by 20%.
Numerical Analysis for Performance Evaluation of Round Tubes Inserted With Corrugated Twisted Tape
Authors: Gupta Kalpana , Singh Raj Kumar , Choudhary Naman , Mukhopadhyay Subham
Published: January 2020

Varieties of heat transfer enhancement techniques developed by different researchers. Heat transfer augmentation techniques refer to different methods used to increase rate of heat transfer and basically divided into active, passive and compound heat transfer enhancement technique. Use of twisted tape is one such promising passive heat transfer augmentation technique. In this work a novel design of twisted tape is introduced. An attempt has been made to analyze the effect of newly designed twisted tape on heat transfer enhancement using computational Fluid Dynamics (CFD) Techniques. Physical time and energy considered for experimentation will be more so in present work simulation has been carried out using ANSYS FLUENT software to find performance of novel twisted tape. The tape considered here is corrugated twisted tape in which corrugations are given longitudinally with fixed angle of corrugation then it is twisted. Comparison in performance of tube without tape, with plain twisted tape and twisted corrugated tape has been done. Verification of model has been done using available correlations for plain tube and tube with plain twisted tape. Range of Reynolds varied from 10,000 to 60,000. Heat transfer and pressure drop characteristics studied using computational analysis. Nusselt Number and friction factor of round tube with CTT insert is found to be 1.79–1.94 times and 2.5–3.5 times higher respectively compared to round tube without any insert. Thermal performance factor chosen as performance evaluation criteria keeping pumping power constant. Performance of tube with corrugated twisted tape insert found to be better than plain tube (improvement in TPF up to 31%) taking into account both heat transfer and friction factor.
Motion Synthesis for Upper-Limb Rehabilitation Motion With Clustering-Based Machine Learning Method
Authors: Chen Wenxiu , Song Wanbing , Chen Haodong , Li Qi , Zhao Ping
Published: January 2020

Nowadays, mechanical devices such as robots are widely adopted for limb rehabilitation. Due to the variety of human body parameters, the rehabilitation motion for different patient usually has its individual pattern. Thus it is obviously not an optimal solution to use a single motion generator to suit all patients. Yet it would also be unpractical if we design a different motion or even a different mechanism for each user individually. Therefore, in this paper we seek to adopt clustering-based machine learning technique to find a limited number of motion patterns for upper-limb rehabilitation, so that they could represent the large amount of those from people who have various body parameters. Firstly, the trajectory of a specified rehabilitation motion are recorded from various subjects, and then 4 types of machine learning algorithms (spectral clustering, hierarchical clustering, self-organizing mapping neural network and Gaussian mixture model) are implemented and compared. It is shown that spectral clustering (SC) yields the best performance and is hereby adopted to generate three clusters of motion patterns. After regression of each cluster, three types of motion for upper limb-rehabilitation are constructed, which could reflect the trajectories’ similarity and difference of people who have various body parameters. These work will provide help for the design of rehabilitation mechanisms.
Modelling Buoy Motion at Sea
Authors: Rykkje Thorstein R. , Tørressen Tord , Løkkebø Håvard
Published: January 2020

This project creates a model to assess the motion induced on a buoy at sea, under wave conditions. We use the Moving Frame Method (MFM) to conduct the analysis. The MFM draws upon concepts and mathematics from Lie group theory — SO(3) and SE(3) — and Cartan’s notion of Moving Frames. This, together with a compact notation from geometrical physics, makes it possible to extract the equations of motion, expeditiously. This work accounts for the masses and geometry of all components and for buoyancy forces and added mass. The resulting movement will be displayed on 3D web pages using WebGL. Finally, the theoretical results will be compared with experimental data obtained from a previous project done in the wave tank at HVL.
Physical Data Auditing for Attack Detection in Cyber-Manufacturing Systems: Blockchain for Machine Learning Process
Authors: Song Jinwoo , Shukla Diksha , Wu Mingtao , Phoha Vir V. , Moon Young B.
Published: January 2020

Auditing physical data using machine learning can enhance the security in Cyber-Manufacturing System (CMS). However, the physical data processing itself is prone to cyber-attacks. Connections based on the internet in CMS opens the route for adversaries to compromise the attack detection system itself.

To prevent data from malicious data injection in CMS, this paper proposes an enhanced Simple Convolutional Neural Network (SCNN) based attack detection system employing a blockchain. There are three contributions of this paper: (i) introducing a secure attack detection system using blockchain, (ii) optimizing the cost and time for CMS by training on the simulated images, and (iii) presenting a real-time attack detection system for CMS by simplifying the convolutional neural network.

The paper demonstrates the effectiveness of the blockchain implementation by presenting the comparative performance analysis of the proposed attack detection system with and without blockchain implementation using an example of a simulated attack on the machine learning process.
High-Temperature Oxidation Modeling of New Perspective Accident Tolerant Fuel Claddings
Authors: Vasiliev Alexander
Published: January 2020

Currently, the comprehension among the specialists and functionaries is getting stronger that the nuclear industry can encounter serious difficulties in development in the case of insufficiently decisive measures to enhance the safety level of nuclear objects. The keen competition with renewable energy sources like wind, solar or geothermal energy takes place presently and is expected to continue in future decades. One of main measures of nuclear safety enhancement could be the drastic renovation of materials used in nuclear industry.

The analytical models of high-temperature oxidation of new perspective materials including chromium-nickel-based alloys, zirconium-based cladding with protective chromium coating, FeCrAl alloys and composite claddings on the basis of SiC/SiC in the course of design-basis and beyond-design-basis accidents at nuclear power plants (NPPs) are developed and implemented to severe accident computer running code. The comparison with available experimental data is conducted.

The preliminary calculations of nuclear pressurized water reactor loss-of-coolant accidents with new types of claddings demonstrate encouraging results for hydrogen generation rate and integral hydrogen production. It looks optimistic for considerable upgrade of safety level for future generation NPPs using new fuel and cladding materials.
CFD Analysis of Reversed Installation on Flow Measurements by a Plate Orifice
Authors: Zheng Dezhi , Ma Haibo , Silaen Armin K. , Zhou Chenn Q.
Published: January 2020

The accidental reversal installation of an orifice plate could occur during maintenance operations and a long time may have elapsed before being noticed. The reversal installation can result in a significant mismeasurement of flow in a pipe. In the paper, a computational fluid dynamics (CFD) model has been developed to simulate the pressure and velocity distribution in a pipe with the correct and the reversed installation of an orifice plate. The results shown that there is a significant difference between the correct and reversed installation in terms of pressure. Using the CFD pressure drop results for flows in both installations, an estimate correlation between those installations was found. This result provides the method to solve the issue about the accidental reversal of an orifice plate using a correction factor.
Buckling of Tube for Tube Hydroforging
Authors: Nikhare Chetan P.
Published: January 2020

Tube forming is one of the most common manufacturing processes to shape the tubes. Within tube forming operations the general practice is to expand and reduce the tube end cross-section and bend the tube by means of a solid mandrel. Mostly the mandrel is rigid bodies. To reduce the friction between the tube and the tool, tube hydroforming process was evolved in which the fluid was highly pressurized to expand the tube shape to the desired shape. By reducing the friction more uniform thickness could be achieved and thus increase in formability. In this paper, the tube was formed in two steps with low fluid pressure and axial force. The tube will be allowed to a useful maximum buckle by applying the axial force and/or a ramp internal pressure which then hydroforged with constant pressure for the maximum expansion ratio. The buckling mechanics of tube with respect to the fluid pressure and the axial force was studied. Further, the pressure requirement for hydroforging was investigated with respect to the length of the tube. The strain pattern and thickness distribution were studied in the buckling/bulging and hydroforging step.
Analysis of Planar-Cavity Receiver Reactor for Solar Thermochemical Dry-Reforming
Authors: Gifford Jeffrey , Davenport Patrick , Ma Zhiwen , Martinek Janna , Turchi Craig , Weissman Jeffrey G.
Published: January 2020

Concentrating solar thermal (CST) systems can be leveraged to provide not only heat for power generation, but also for energy storage and thermochemical fuel production. Such solar thermochemical processes have been studied conceptually, from solar thermochemical hydrogen production (STCH) and thermochemical energy storage (TCES), to gasification, reforming, and fuel upgrading by various means. The solar receiver and reactor are critical components in the conversion of solar energy into chemical energy in the form of “solar fuels’. For effective conversion of solar energy within a coupled solar receiver-reactor, extremely high temperatures are required, thereby demanding a high solar concentration ratio (CR) for efficient operation. This creates a design challenge for the receiver-reactor, as many thermochemical processes involve gas or gas-solid systems that are limited by low heat transfer coefficients. A unique receiver design is proposed that has the potential to incorporate various high-temperature thermochemical processes such as TCES-assisted power generation, methane reforming, or STCH processes. Modeling this receiver and its potential applications requires a full three-dimensional model that accurately captures the interconnected effects of receiver geometry, spatial solar irradiance, complex radiation, reaction kinetics, fluid dynamics, and heat transfer. In this paper we analyze a CST system integrated with this unique planar-cavity receiver-reactor design using the developed model. The model presented in this paper showed where improved thermal management was needed to achieve suitable receiver performance when a dry-methane reforming process is implemented.
Conventional and Advanced Exergoeconomic Analysis in a Nitric Acid Production Plant
Authors: Fajardo J. , Buelvas A. , Valle H.
Published: January 2020

An advanced exergoeconomic analysis (AEA) allows determining the part of Exergy Destruction and total investment costs that can be avoided. The results of the advanced analysis show the economic costs to be reduced and improvements that can be achieved for the system in terms of the overall efficiency. A Nitric Acid Production Plant of 350 tons/day was taken as case of study to implement a conventional and advanced exergoeconomic analysis. In this work, the investment costs and exergy destruction of the components of the system were divided into 2 groups such as endogenous/exogenous and avoidable/unavoidable parts to obtain accurate information about the performance of the plant.

Conventional exergoeconomic analysis showed that 58.5% of the total cost of the exergy destruction is caused by the catalytic converter with a cost rate of 687.84 $/h. The highest values of the exergoeconomic factor were for Tail Gas Desuperheater (99.01%), Condenser (96.35%) and Tail Gas Heater (87%). The costs of the production process can be improved by reducing the total investment of these three components. The lowest value of exergoeconomic factor was calculated for the Catalytic Converter (15.25%) which implies that thermodynamic efficiency of this equipment must be enhanced.

Based on AEA results, most exergy destruction of the Catalytic Converter is avoidable and exogenous. The destruction cost of the avoidable exergy for this component was 54.4 $ / h, which means that more than 50% of the total cost of the exergy destruction of the Catalytic Converter can be minimized to improve the performance of other equipment of the plant.

Most exergy destruction costs for Tail Gas Heater, Absorption Tower and Air Heater, are unavoidable and endogenous and they cannot be reduced by improving the performance of these equipments. In addition, the cost of the exergy destruction of the Tail Gas Desuperheater is largely unavoidable (66.9 $ / h).

In particular, 85%, 88% and 83% of the investment cost of the Tail Gas Desuperheater, the Absorption Tower and the Catalytic Converter, respectively, are exogenous; that is, it is only affected by the structure of the plant and the operation of the other components, but not by its internal thermodynamic inefficiencies.
Ionic Liquid As Cutting Fluid Additive Using Minimum Quantity Lubricant (MQL) in Titanium-Ceramic Contact
Authors: A. Magar Sameer , Guo Hong , Iglesias Patricia
Published: January 2020

Titanium alloys have a wide range of application in the field of automotive, biomedical and the civil industry due to its excellent material properties such as high thermal resistance, high load bearing capacity and high corrosion resistance. However, the high cost of machining titanium limits its application in aerospace and shipbuilding industry. Minimum quantity lubrication (MQL) has emerged as a new lubrication technique to achieve sustainable and profitable machining, but multiple studies show that conventional cutting fluid in MQL is not sufficient to reduce the friction and the associated effects. Recently, ionic liquids have shown a great potential in reducing the friction and wear of materials in contact. This study focuses on using an environment-friendly protic ionic liquid (PIL) tri-[bis (2-hydroxyethylammonium)] citrate (DCi) as an additive to a biodegradable oil (BO) used as lubricant in a ball-on-flat reciprocating tribometer in the titanium-ceramic contact at three different frequencies (3Hz, 4Hz and 5 Hz) under different loads. Results show a maximum 50% reduction in friction coefficient and 23% wear reduction at a frequency of 5 Hz under a normal load of 2 N by using 1 wt% DCi as an additive to BO as compared to using neat BO as the lubricant.
Control of Cold Plate Temperature in a Pumped Two Phase Flow
Authors: Sinha Alok , Byrd Larry W.
Published: January 2020

One of the main goals of a pumped two-phase flow cooling system is to ensure that there is a two phase flow at the exit of the cold plate so that the heat transfer coefficient remains very high. To decrease the mass flow rate but still prevent dryout, there is a motivation to maintain the exit quality at roughly 0.6 to 0.7 for an unknown time-varying heat load. In this paper, a simple output feedback control algorithm is proposed to achieve this goal. A nonlinear model based on the conservation of mass, momentum, and energy is used. Steady state solutions and their stability are analyzed. Results from numerical simulations with R134a flow corroborate the validity of the proposed novel feedback control algorithm.
Magnetic-Based Particle Tracking in a Dense Granular Shear Flow
Authors: Tao Xingtian , Wu Huixuan
Published: January 2020

Granular material is ubiquitous in nature and plays a significant role in industry. Researchers have paid a lot of attention to density and velocity distributions of dense granular flows. However, the motion of individual particle is hard to capture because visualizing individual particles in a dense granular flow, especially in 3D, is very difficult and could be expansive. Here we use the magnetic particle tracking (MPT) technique to capture the motion of a single particle in a sheared dense granular flow. The accuracy of MPT is quantified using experimental results. The sheared granular flow is generated in a Couette cell by rotating a plate at the bottom of a cylinder container. It is able to generate different shear stresses by controlling the speed of the plate. By tracking the magnetic particle in the cylinder, we can capture the velocity of an individual particle at different locations in the granular flow.
Development of Contactless Torque Sensor Based on SAW Resonators
Authors: Han Wei , Bu Xiongzhu , Cao Yihan , Xu Miaomiao
Published: January 2020

This paper presents a wireless clamp-on torque sensor based on dual or quad one-port SAW resonators to meet the measurement requirements of transmission system. Firstly, the principle of clamp-on torque sensor is introduced, the mechanical model of the structure is calculated and simulated by theoretical analysis and COMSOL. The differential measurement method is confirmed, and the optimal structure parameters are studied. Then, the torque sensitive theory of SAW devices is analyzed, the differential SAW torque sensing elements and the measurement system are designed based on the frequency division multiple access (FDMA). And a novel sensing element installation method is proposed, which reduces the installation error influence on sensor accuracy. Finally, the clamp-on structure prototype and measurement system are verified by the static calibration experiment. The results show that: the torque sensor has the capability that 1.931 KHz/Nm of sensitivity under ±100 Nm with good linearity and consistency. The torque sensor has the advantages of wireless, non-contact, easy installation, high reliability, and easy maintenance, it is suitable for the torque measurement of transmission system.
The Effect of the Embedded Spacers on the Performance of Direct Contact Membrane Distillation System Operating With Different Inlet Feed Temperature
Authors: Alwatban Anas M. , Alshwairekh Ahmed M. , Alqsair Umar F. , Krysko Robert , Alghafis Abdullah A. , Oztekin Alparslan
Published: January 2020

Computational fluid dynamics simulations are used to model the effect of the inlet feed temperature in direct contact membrane distillation modules. Embedded spacers are used as a local mixing promoter tool. Net-type spacers of angle 45° are used as spacers. The presence of the spacers will mitigate the temperature and concentration polarization effects. The calculation of the vapor flux through the membrane is based on the Dusty-Gas model. The membrane is considered as a functional surface, and the embedded spacers are treated as impermeable surfaces. The vapor flux equation couples the variation of the vapor flux in the feed and the permeate channel with the variation of the feed concentration along the membrane. The flow is considered turbulent in channels containing embedded spacers. The k–ω SST turbulent model is used to characterize the steady-state turbulent structures inside the flow channels. The flow rate in the feed and the permeate channels is fixed. The membrane properties are also fixed. The inlet feed temperature is varying while fixing the inlet permeate temperature. The results indicate that the embedded spacers increase the vapor flux permeation while the temperature and concentration polarizations are mitigated. As the inlet feed temperature is increased, the effect of the embedded spacers becomes more significant.