bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Gravity Effects on Electrically Driven Liquid Film Flow Boiling: A Micro-Gravity Flight Campaign in Preparation of ISS Experiment
Authors: Castaneda Alexander J. , O’Connor Nathaniel J. , Yagoobi Jamal 
Published: February 2021

Abstract
The ongoing development of modern electronic systems leads to smaller, more powerful devices that are expected to operate in complex environments. Due to this, advanced thermal management technologies are required to meet the growing demand, especially in space where two-phase thermal systems are limited by the absence of gravity. Electrohydrodynamic (EHD) and dielectrophoretic (DEP) forces can be used to sustain stable liquid film boiling in micro-gravity, which is otherwise impractical due to the lack of a required buoyancy force to initiate bubble departure. EHD and DEP are phenomena that are represented by the interaction between electric fields and fluid flow. The DEP force especially is characterized by the unique ability to act on liquid/vapor interfaces due to a high gradient of electrical permittivity, allowing for two phase operation. This study investigates the effect of EHD conduction pumping coupled with DEP vapor extraction on liquid film flow boiling during a microgravity parabolic flight, and it characterizes the future two-phase microgravity heat transport technology prior to testing on the International Space Station (ISS). The results of this study show that EHD and DEP raise critical heat flux, lower heater surface temperature, and successfully sustain boiling in micro-gravity all at the cost of low power consumption. Additionally, the heat transfer data captured in terrestrial, microgravity, and 1.8 g conditions compare well, indicating that this technology can provide thermal enhancement independent of gravity. This study paves the way for future implementation of EHD-driven two-phase heat transport devices into space and aeronautical electronics applications.
Nonlinear Control Design for a Gravity Compensation Mechanism for Human Lower Limb Rehabilitation
Authors: Ilhan Zeki Okan , Chew Meng-Sang 
Published: February 2021

Abstract
Dynamics of a two degree-of-freedom suspension mechanism is incorporated into nonlinear control design to facilitate its potential use as a rehabilitation device to aid people with lower-limb injuries. The proposed mechanism is a variation of the standard four-bar linkage with an extra link and two springs. The system dynamic model is first extracted based on the Lagrange’s equations in conservative form. The performance deviations due to the link inertia is demonstrated in open-loop numerical simulations under an impulsive force scenario. Finally, the dynamic model of the suspension mechanism is incorporated into feedback control design based on nonlinear, sliding mode control strategy that can add robustness against modeling uncertainties and external disturbances. The tracking performance of the proposed nonlinear controller is validated in closed-loop numerical simulations to demonstrate possible performance improvements under feedback control.
Thermal Management of a Reversible Solid Oxide System for Long-Term Renewable Energy Storage
Authors: Mottaghizadeh Pegah , Fardadi Mahshid , Jabbari Faryar , Brouwer Jack 
Published: February 2021

Abstract
In this study, an islanded microgrid system is proposed that integrates identical stacks of solid oxide fuel cell and electrolyzer to achieve a thermally self-sustained energy storage system. Thermal management of the SOEC is achieved by use of heat from the SOFC with a heat exchanger network and control strategies. While the SOFC meets the building electricity demand and heat from its electrochemical reactions is transferred to the SOEC for endothermic heat and standby demands. Each component is physically modelled in Simulink and ultimately integrated at the system level for dynamic analyses. The current work simulates a system comprised of a wind farm in Palm Springs, CA coupled with the SOEC (for H2 generation), and an industrial building powered by the SOFC. Results from two-weeks of operation using measured building and wind data showed that despite fluctuating power profiles, average temperature and local temperature gradients of both the SOEC and SOFC were within desired tolerances. However, for severe conditions of wind power deficit, H2 had to be supplied from previous windy days’ storage or imported.
Experimental Investigation of the Settling of Carbon-Based Nanoparticles in Renewable Jet Fuel
Authors: Hentges Nicholas , Singh Gurjap , Ratner Albert 
Published: February 2021

Abstract
Recent studies have shown that the addition of nanomaterials to fuels can improve combustion characteristics. A downside, however, is that these mixtures are unstable and prone to phase separation. Finding stable nanomaterial-fuel mixtures are required to make these mixtures viable for practical use. Current research studied the stability of Renewable jet fuel combined with multiple nanomaterial additives being acetylene black, graphene nanoparticles, and multiwalled carbon nanotubes, at 1.0% w/w ratio. Results were compared with prior research and it was shown that renewable jet fuel had a similar effect on settling as soy biodiesel and the results indicated that the fuel’s bulk viscosity was not a major factor determining the stability of the nanofuel.
Arm Movement Analysis in Human Daily Life for Improving Durability of Artificial Elbow Joint
Authors: Kamio Chihiro , Aihara Tatsuhito , Minorikawa Gaku 
Published: February 2021

Abstract
Human movement data can contribute to the quality improvement of industrial and medical products affected by such movement. Such data can be used to improve the quality of industrial products as well as in healthcare applications, such as the development of artificial joints. To develop and design artificial joints with enhance durability, it is necessary to set up standards of durability using human movement data in daily life. The aim of this study is to obtain data that contributes to the improvement in durability of artificial elbow joints. We have developed a wearable device that can measure its self-acceleration, angular velocity, and quaternions to collect human movement data continuously for long-term. Additionally, we collected the arm movement data of 30 participants using the developed device. The participants of this study carried on with their normal lives with the measuring device worn on their wrist. This study calculated the posture of the wrist over time using quaternions and mainly analyzed posture changes. We clarified the characteristics and trends of the movement of bending the elbow in daily human life.
High Cycle Fatigue Behavior of Recycled Additive Manufactured Electron Beam Melted Titanium Ti6Al4V
Authors: Mojib Melody , Pahuja Rishi , Ramulu M. , Arola Dwayne 
Published: February 2021

Abstract
Metal Additive Manufacturing (AM) has become a popular method for producing complex and unique geometries, especially gaining traction in the aerospace and medical industries. With the increase in adoption of AM and the high cost of powder, it is critical to understand the effects of powder recycling on part performance to move towards material qualification and certification of affordable printed components. Due to the limitations of the Electron Beam Melting (EBM) process, current as-printed components are susceptible to failure at limits far below wrought metals and further understanding of the material properties and fatigue life is required. In this study, a high strength Titanium alloy, Ti-6Al-4V, is recycled over time and used to print fatigue specimens using the EBM process. Uniaxial High Cycle Fatigue tests have been performed on as-printed and polished cylindrical specimens and the locations of crack initiation and propagation have been determined through the use of a scanning electron microscope. This investigation has shown that the rough surface exterior is far more detrimental to performance life than the powder degradation occurring due to powder reuse. In addition, the effects of the rough surface exterior as a stress concentration is evaluated using the Arola-Ramulu. The following is a preliminary study of the effects powder recycling and surface treatments on EBM Ti-6Al4V fatigue life.
Uncertainty Quantification in Predicting Behaviour of Rubber-Like Materials in Uni-Axial Loading
Authors: Ghaderi Aref , Morovati Vahid , Nasiri Pouyan , Dargazany Roozbeh 
Published: February 2021

Abstract
Material parameters related to deterministic models can have different values due to variation of experiments outcome. From a mathematical point of view, probabilistic modeling can improve this problem. It means that material parameters of constitutive models can be characterized as random variables with a probability distribution. To this end, we propose a constitutive models of rubber-like materials based on uncertainty quantification (UQ) approach. UQ reduces uncertainties in both computational and real-world applications. Constitutive models in elastomers play a crucial role in both science and industry due to their unique hyper-elastic behavior under different loading conditions (uni-axial extension, biaxial, or pure shear). Here our goal is to model the uncertainty in constitutive models of elastomers, and accordingly, identify sensitive parameters that we highly contribute to model uncertainty and error. Modern UQ models can be implemented to use the physics of the problem compared to black-box machine learning approaches that uses data only. In this research, we propagate uncertainty through the model, characterize sensitivity of material behavior to show the importance of each parameter for uncertainty reduction. To this end, we utilized Bayesian rules to develop a model considering uncertainty in the mechanical response of elastomers. As an important assumption, we believe that our measurements are around the model prediction, but it is contaminated by Gaussian noise. We can make the noise by maximizing the posterior. The uni-axial extension experimental data set is used to calibrate the model and propagate uncertainty in this research.
Design of a Simple Experimental Setup for P-I-D Control Testing
Authors: Ilhan Zeki Okan , Loveland William , Baker Justiz 
Published: February 2021

Abstract
This work aims to demonstrate the use of a simple experimental setup for accurate position control, which will be used to supplement the senior level “Control Systems” class taught in McCoy School of Engineering at Midwestern State University. The experimental setup is an unstable, doubleintegrator system, which consists of a ping-pong ball rolling on a pivoted beam. The control task is to stabilize the ball at the center of the beam by systematically changing the angle of rotation of the beam through the servomotor. The experimental setup is built out of 3D-printed parts, and simple electronics are used for controls. A control-oriented dynamic model is first obtained based on the standard Lagrangian approach and the model is linearized to simplify the control design. Proportional Integral Derivative (PID) controller is then designed based on the system transfer function, and the performance of the PID controller is tested in closed-loop numerical simulations in MATLAB-SIMULINK environment. Finally, the proposed PID algorithm is implemented in the actual setup using the ARDUINO microcontroller platform. Performance of the PID controller is discussed based on the initial results and possible improvement areas are addressed.
Rapid Configuration and Launch of a UAS Swarm for Post-Nuclear Blast Response
Authors: Renard Michael , Anderson Matthew , Rose Luke , Johnston Murray , Walter William , Kopeikin Andrew 
Published: February 2021

Abstract
A multi-disciplinary team of West Point cadets developed an Unmanned Aircraft System (UAS) swarm to provide automated remote sensing of radiation sources and hazards following a nuclear blast. The swarm employs autonomous and adaptive distributed control algorithms to survey (1) a radiation fallout plume to map its contour, and (2) a road network to visually identify obstacles to ground travel. To effectively conduct these missions USMA designed modifications to a fleet of Tarot 650 drones to interface with an existing swarming infrastructure, and to enable rapid tool-free integration of the required sensor suite. In addition, a rapid deployment launcher was designed to safely transport, power, and remotely launch the UAS from the back of a HMMWV. This paper describes considerations and analyses that supported the integrated mechanical and electrical designs, as well as a description of the resulting product. Flight testing was conducted to demonstrate the functionality of most of the designed components. Following the COVID-19 shutdown, the team pivoted to remote subcomponent testing, and computer simulation to demonstrate the remaining functions.
Development of Analytical Force Model for End Milling of Magnesium Matrix Composites
Authors: Anandan Nishita , Ramulu M. 
Published: February 2021

Abstract
An analytical approach to predict the cutting forces in end milling of magnesium metal matrix composite is presented in this study. The model was developed by identifying three events that occur when the cutting edge encounters the composite, when an element of the cutting edge encounters just the particles, it may fracture the particle, when the element encounters pure ductile matrix, plastic deformation occurs and when the element is in contact with both the particle and matrix, particle debonding occurs due to mismatch in coefficient of thermal expansion. The probability of these events was estimated using the particle concentration and the distribution in the matrix. A cutting force model is developed by considering the stresses and forces experienced by the cutting edge contributed by these events. The predicted feed forces and the measured forces are in good agreement for most of the cutting conditions. While, the predictive thrust forces were found to diverge at higher feed of 1 mm/rev.
Chemical Kinetic Study on Reaction Pathway of Anisole Oxidation at Various Operating Condition
Authors: Roy Shrabanti , Askari Omid 
Published: February 2021

Abstract
Biofuels are considered as an alternative source of energy which can decrease the growing consumption of fossil fuel, hence decreasing pollution. Anisole (methoxybenzene) is a potential source of biofuel produced from cellulose base compounds. It is mostly available as a surrogate of phenolic rich compound. Because of the attractive properties of this fuel in combustion, it is important to do detail kinetic study on oxidation of anisole. In this study a detail chemical mechanism is developed to capture the chemical kinetics of anisole oxidation. The mechanism is developed using an automatic reaction mechanism generator (RMG). To generate the mechanism, RMG uses some known set of species and initial conditions such as temperature, pressure, and mole fractions. Proper thermodynamic and reaction library is used to capture the aromaticity of anisole. The generated mechanism has 340 species and 2532 reactions. Laminar burning speed (LBS) calculated through constant volume combustion chamber (CVCC) at temperature ranges from 460–550 K, pressure of 2–3 atm and equivalence ratio of 0.8–1.4 is used to validate the generated mechanism. Some deviation with experimental result is observed with the newly generated mechanism. Important reaction responsible for LBS calculation, is selected through sensitivity analysis. Rate coefficient of sensitive reactions are collected from literature to modify and improve the mechanism with experimental result. The generated mechanism is further validated with available ignition delay time (IDT) results ranging from 10–20 atm pressure, 0.5–1 equivalence ratio and 870–1600 K temperature. A good agreement of results is observed at different operating ranges. Oxidation of anisole at stoichiometric condition and atmospheric pressure in jet stirred reactor is also used to compare the species concentration of the mechanism. This newly generated mechanism is considered as a good addition for further study of anisole kinetics.
Convective Air Drying of Stationary and Moving Moist Porous Medium With Slot Jet Reattachment Nozzle: A Numerical Study
Authors: Farzad Milad , Yagoobi Jamal 
Published: February 2021

Abstract
Drying is an omnipresent operation present in various industrial sectors such as food and agriculture, forestry products, chemicals, and pharmaceuticals. Convective hot air drying with conventional impinging jet nozzles is among the widely used techniques in drying of moist porous materials. However, this method is generally inefficient in drying of fragile materials as a low air flow rate is required to avoid potential damage to the product due to the exerted force by impinging jet. To improve the drying efficiency and enhance the product quality, slot jet reattachment (SJR) nozzle has been developed as an alternative technology to the common in-line jet nozzle, slot jet (SJ) nozzle, and perforated plate. SJR nozzle allows for the control of the exerted impingement force by simply changing its exit angle.
This paper numerically investigates the convective air-drying characteristics of an SJR nozzle and compares it to those of a common SJ nozzle for a moist porous medium. The comparison is made under identical air mass flow rate criterion. The results are presented for stationary and moving reattachment surface under a laminar flow condition. The governing transport equations within a moist porous medium are coupled with the governing equations of the resultant air flow. The results indicate a much higher drying rates with SJR nozzle compared to SJ nozzle.
Nonlinear Dynamics of a Dielectric Elastomer Membrane Under Compressive Loading
Authors: Lowe Robert L. , Cooley Christopher G. 
Published: February 2021

Abstract
This paper investigates the nonlinear dynamics of square dielectric elastomer membranes under time-dependent, through-thickness compressive loading. The dielectric elastomer is modeled as an isotropic ideal dielectric, with mechanical stiffening at large strains captured using the Gent hyperelastic constitutive model. The equation of motion for the in-plane membrane stretch is derived using Hamilton’s principle. The static response of the membrane is first investigated, with equilibrium stretches calculated numerically for a wide range of compressive pre-loads and applied voltages. Snap-through instabilities are observed, with the critical snap-through voltage decreasing with increasing compressive pre-load. The dynamic response of the membrane is then investigated under forced harmonic excitation. Frequency response plots characterizing the steady-state vibration reveal primary, subharmonic, and superharmonic resonances. Near these resonances, two stable vibration states are possible, corresponding to upper and lower branches in the frequency response. Significant and practically meaningful differences in the dynamic response are observed when the system vibrates at a fixed frequency about the upper and lower branches, a feature not discussed in previous research.
Design and Performance of Nonlinear Control for an Electrohydraulic Actuator Used on Shaker Table
Authors: Borrás Pinilla Carlos , Quintero Edwin Ferney 
Published: February 2021

Abstract
Hydraulic actuators are widely used in industrial applications due to their excellent power-size relation, their capacity to apply high forces indefinitely, and their high response. Hydraulic servo systems combine the advantages of hydraulic actuators with the versatility of electronics to give the most powerful actuators in modern industrial applications like robotics, aerospace industry, mining, testing equipment, and production lines.
Hydraulic dynamic systems are usually described by linear or linearized models around operating points. In this work a nonlinear dynamic and mathematic model for the position control of a double rod hydraulic servo actuator was developed.
Three control strategies were implemented: optimal control (LQR), control by Feedback Linearization, and Sliding Mode Control. For the optimal control (LQR) strategy a linearized model of the hydraulic actuator was developed around a specific operating point, contrary to the Feedback Linearization and Sliding Mode control that have a wide operation range and the nonlinear model was used. The Sliding Mode control was designed using a scheduling switch to change between two sliding mode controls and to avoid the chattering problem a solution base in the limit region was used.
Furthermore, it was obtained that depending on the industrial application and the requirements of the position control of a hydraulic actuator, engineers can decide which control strategy to apply. Scheduling sliding mode control is better for industrial applications where it is important to have a rapid and accurate response, low control effort, low energy consumption, and robustness in the presence of disturbances. Feedback linearization control is also an excellent control strategy with rapid response and low control effort. But in certain applications, where there is no fast response, nor extreme precision needed, the LQR control is a great option.
A Directional Damage Constitutive Model for Stress-Softening in Solid Propellant
Authors: Chen Yang , Morovati Vahid , Dargazany Roozbeh 
Published: February 2021

Abstract
Solid propellants are particulate composite with a light cross-linked elastomeric binder filled with a high concentration of energetic, solid aggregates. Solid propellants are often considered as highly nonlinear elastomeric materials, with elastic behavior resulted from its binder and plastic behavior from its energetic particles. The study of the micro-structure and mechanical properties of solid propellant is crucial for its design, safety evaluation, and lifetime prediction of solid fuel carriers. The constitutive model proposed for rubber-like material can often be generalized to predict the nonlinear behavior of solid propellant due to the dependency on the mechanical behavior of solid propellant on its elastomeric binder material. This paper focuses on developing a model that predicts the stress softening and strain-residual mechanism of the solid propellant. This micro-mechanical model for solid propellant was proposed based on the network evolution theory. The motivation of this study is the lack of a micro-mechanical model that can describe both the stress softening effect and strain residual in the quasi-static behavior of propellants. The simplified network-evolution model with only five parameters is a simple micro-mechanical model that captures both the stress softening effect and strain residual. Besides the simplicity and reduced fitting procedure, the model was validated against several experimental data and illustrated good agreement in small and large deformations, making the proposed model a suitable option for commercial and other applications.