bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of High-Pressure Laminar Flame Speed Measurement
Authors: Shaffer James , Alvarez Luis F. , Askari Omid 
Published: February 2024

Abstract
Laminar burning speed (LBS) measurements are a significant fundamental experiment in understanding the combustion characteristics of fuels of interest. Such information is necessary for many applications such as engine design or modeling more complicated combustion phenomena. For example, to improve the thermal efficiency of combustion devices such as turbines or jets, it is generally necessary to operate at higher pressure or with lean fuel mixtures. Therefore, accurate measurement of fuels under these relevant conditions is of interest to accurately simulate the behavior of such devices. At these desired experimental conditions, the flame is often affected by instabilities (surface wrinkling and buoyancy), which can make LBS measurement challenging or impossible. Such instabilities are enhanced (occur earlier in the flame propagation) at high pressure where the flame thickness is decreased and propagates at a slower speed. This work demonstrates that the inclusion of flame propagation data at small geometries (r &lt; 8 mm) can improve the measurement of LBS through the addition of early flame propagation. In the conventional measurements, flames of this size are excluded from analysis because experimental data is affected by the ignition plasma source. The effect of ignition on the propagation rate is in general not known, and an accurate time-resolved method for characterizing ignition for use in LBS measurements is not available. It has been found that an improved LBS measurement method can be developed if the ignition can be accurately characterized.
Investigation Into Mechanical Properties of Expanded Polystyrene Fresh Fish Boxes Using Finite Element Analysis and Experimental Methods
Authors: Lu Ziwei , Jónsdóttir Fjóla , Arason Sigurjón , Margeirsson Björn 
Published: February 2024

Abstract
Expanded polystyrene (EPS) is used as packaging material in transportation. To reduce environmental impact, it is crucial to minimize the consumption of packaging materials and maximize strength meanwhile. To reduce consumption, reducing the density of EPS is one method, and structural optimal design is the other. Therefore EPS boxes with densities of 22 kg/m3 are introduced to compare with the mass-produced 23-kg/m3 model. Regarding structural optimal design, as compressive and flexural properties underlie the optimization of structures and have been well-studied in construction, they have not been thoroughly explored in packaging. Material parameters obtained from a compression test are used in a finite element simulation of a stacking test, and good agreement is observed between the simulation and experimental results. The findings indicate that density impacts the initial modulus and compression/flexure strength, as well as the stacking strength of a box to some extent. The study investigates box failure and uses theoretical calculation, simulation, and experimentation to determine the critical force, with all findings showing agreement. The study also examines how sample preparation methods affect mechanical properties, specifically comparing cutting EPS with a hot wire and a table saw, and finds that differences are typically around 2%.
Measurement of Optimum Laser Energy Required to 3d Print Continuous Fiber Reinforced Composites Using Photo-Curable Thermoset Resin
Authors: Islam Md Zahirul , Rahman Md Atikur , Gibbon Luke , Hall Eric , Ulven Chad A. , La Scala John J. 
Published: February 2024

Abstract
Continuous carbon fiber (CCF) reinforcement has garnered significant attention in 3D printing due to its ability to impart exceptional mechanical performance characteristics to polymer composites. Light-assisted 3D printing of thermoset resin with CCF reinforcement enables the scalable production of complex structures using additive manufacturing. However, the opaqueness of carbon fiber poses challenges to the curing process of thermoset resins during printing with CCF reinforcement. Therefore, knowledge on the minimum light energy required to continue printing while retaining the desired print shape is crucial for designing energy-efficient and successful manufacturing systems. The primary objective of this study was to measure and compare the minimum energy required to continue light-assisted 3D printing of thermoset resin with CCF reinforcement. The study specifically investigated the minimum light energy needed for printing with both an acrylate-based thermoset resin and an epoxy-acrylate resin. Optimized laser irradiation with the appropriate light energy is imperative for achieving scalable production of CCF reinforced composites with minimum energy consumption.
A Dynamic Model for Underwater Propulsion of an Amphibious Rover Developed From Kane’s Method
Authors: Donohue Brigid , Beknalkar Sumedh , Bryant Matthew , Mazzoleni Andre 
Published: February 2024

Abstract
The Multi-terrain Amphibious ARCtic explOrer (MAARCO) rover is an amphibious arctic rover designed to traverse arctic terrains and propel through water. The MAARCO rover consists of an ellipsoid chassis with links connecting to the propulsion system. The propulsion system consists of two helical drives made up of hollow cylinder ballasts wrapped in auger or screw shaped blades in opposing helical directions parallel to each other. In this paper, a 6 degree of freedom dynamic model of the MAARCO rover is created using Kane’s method dynamic modeling to demonstrate the dynamic model capabilities for an underwater vehicle’s performance. The hydrodynamic forces considered on the underwater rover include drag, buoyancy, flow acceleration, and added mass. In addition to the hydrodynamic forces the rover will experience gravity forces, control forces, net thrust from the helical drive blades, and net buoyancy from the helical drive ballast system. The equations of motion are developed from Kane’s method to reduce computational cost and simulated in MATLAB for different cases to gain further understanding and provide a visual representation of the system underwater and the dynamic models capabilities. The results of the simulations show the MAARCO rover behavior in the hydrodynamic environment. The results reveal that the Kane’s method dynamic modeling successfully develops equations of motion of a complicated system that can be implemented into a control system.
Enhancing Sample Efficiency for Temperature Control in DED With Reinforcement Learning and MOOSE Framework
Authors: Sousa João , Darabi Roya , Sousa Armando , Reis Luís P. , Brueckner Frank , Reis Ana , de Sá José César 
Published: February 2024

Abstract
Directed Energy Deposition (DED) is crucial in additive manufacturing for various industries like aerospace, automotive, and biomedical. Precise temperature control is essential due to high-power lasers and dynamic environmental changes. Employing Reinforcement Learning (RL) can help with temperature control, but challenges arise from standardization and sample efficiency. In this study, a model-based Reinforcement Learning (MBRL) approach is used to train a DED model, improving control and efficiency. Computational models evaluate melt pool geometry and temporal characteristics during the process. The study employs the Allen-Cahn phase field (AC-PF) model using the Finite Element Method (FEM) with the Multi-physics Object-Oriented Simulation Environment (MOOSE). MBRL, specifically Dyna-Q+, outperforms traditional Q-learning, requiring fewer samples. Insights from this research aid in advancing RL techniques for laser metal additive manufacturing.
Analysis of Sustainable Building-Insulation Material Using Biochar and Natural Fiber
Authors: Mondal Sourov Kumar , Gomez Hector , Nasef Ziad , Diaz Gerardo 
Published: February 2024

Abstract
Natural insulation materials like hemp, cotton stalks, cardboard, and paper fiber are of great interest in the construction industry due to their natural composition and sustainability. Biochar can be produced from the pyrolysis of biomass which constitutes a carbon negative process. In this study, an experimental approach is utilized to analyze the effect of using biochar mixed with natural fibers as insulation material with the purpose of using them in the construction industry. Comparative studies were conducted for insulation using natural fibers with and without biochar. The effect of biochar in the thermal performance of the insulation materials is investigated first, by determining the thermal conductivity and R-value from tests. Then compression and bending tests were performed to determine the effect of biochar on the mechanical performance of building-insulation materials. The main contribution of this paper is to investigate the potential utilization of biochar mixed with natural fiber as building-insulation materials to improve fire-retardancy as well as achieving a stable form of carbon sequestration.
Investigation of Mechanically Fatigued Low-Frequency Energy Harvesting Effect on Isotropic Materials
Authors: Meade Daniel , Ahmed Hossain , Ahmed Riaz , Riggs Patrick 
Published: February 2024

Abstract
One of the most popular methods of harvesting electrical energy from mechanical stress is the utilization of piezoelectric materials. A significant amount of research has been done regarding piezoelectric material and has answered questions about what happens to the piezoelectric material during energy harvesting. However, the question that has yet to be answered is what happens to the properties of the material from which energy is being harvested. To answer this question, this study will focus on a simple energy harvesting system is designed that consists of a piezoelectric transducer, voltage regulator, rectifier, and energy storage element to collect energy. The base material from which energy is being harvested is an ASTM standard dog bone test piece of aluminum 6061, structural steel, and copper. To harvest energy from the test specimen, a low-frequency mechanical fatigue load is applied using a fatigue testing machine. Based on the SN curve estimated for the aluminum 6061, structural steel, and copper, the number of fatigue cycles for the test specimen is determined. The maximum fatigue tensile amplitude is set as half of the yield point of the aluminum. The test specimens are designed to go through three types of fatigue cycles which are 50%, 80%, and 100% of their strength. From each set of specimens, energy is harvested from a simulated time as defined in the study. The results of these experiments show a clear correlation between the harvested energy with the material strength of the mechanically fatigued isotropic structures. As the material strength decreases, the amount of energy that is extracted also decreases. Moreover, as the frequency increases, the amount of harvested energy increases exponentially. From each set of specimens, energy is harvested from half the time the experiment runs. At the end of each set of experiments, the ultimate tensile strengths are determined in order to observe if energy harvesting has negative, neutral, or positive effects by comparing the strengths of energy-harvested specimens to the non-harvested tensile strength. To understand the uniform effect of harvesting, the final strength is normalized with the amount of energy being harvested from the material. The results of these experiments show a clear correlation between the harvested energy with the final strength of the mechanically fatigued aluminum structure. As the material strength decreases, the amount of energy that is extracted also decreases. As the frequency increases, the amount of energy increases exponentially.
Development of Sub-Surface Laser Additive Manufacturing Process for Liquid Resins
Authors: Riggs Patrick , Silva Julio , Quirino Rafael , Ahmed Hossain 
Published: February 2024

Abstract
The goal of the present study is to develop original research revolving around plastics-based Laser Additive Manufacturing (LAM) that seeks to improve the current quality, print time, strength, and post-processing needed for LAM. This is accomplished through repurposing a sub-surface laser engraving (SSLE) machine that solidifies bio-resin through thermal polymerization. SSLE machines are traditionally used to create greyscale art pieces that are suspended in a solid crystal block. This is accomplished through focusing the laser below the top surface of the crystal and creating micro-fractures in the material that are around 20–30 μm in size. By keeping the same general process of SSLE, but changing what medium the laser interacts with, this experimental research seeks to replace the micro-fractures with micro-solids through laser induced thermal polymerization in resin. A resin with 50% (weight) of Tung oil is considered for its eco-friendliness. An SSLE machine equipped with a diode pumped Nd: YAG laser is customized to focus laser energy at the subsurface of the resin medium. Several advantages are hypothesized for this new additive manufacturing technique including the elimination of strictly defined layer lines, no longer needing a build plate for the part to build from, the absence of support material as any overhangs will be suspended in the uncured resin, enhancement of surface quality, and the improved strength found from a proposed Body Centered Cubic (BCC) lattice structure of the points. In combining these unprecedented advantages, it is expected that the Sub-Surface Laser Additive Manufacturing (SSLAM) would be an industry-leading advancement with a wide range of applications for commercial product development.
Development of Real-Time Defect Detection Techniques Using Infrared Thermography in the Fused Filament Fabrication Process
Authors: Sadaf Asef Ishraq , Ahmed Hossain , Khan Md Arif Iqbal , Sezer Hayri 
Published: February 2024

Abstract
One of the most popular forms of Additive Manufacturing (AM) is Fused Filament Fabrication (FFF), which allows flexibility to work with multiple materials with comparatively low manufacturing costs. However, uncontrollable process factors lead to the underutilization of the full potential of FFF on an industrial scale due to occasional failure in 3D printed parts. These failures can scale from insignificant to critical defects, which can significantly compromise the overall quality of the product, including desired structural integrity, mechanical property, and reliability of the FDM-produced parts. Post-inspection of the printed part is inconvenient as they result in a loss of labor hours, print time, and print materials. To circumvent these issues, an in-situ real-time defect detection approach is proposed in this study utilizing Infrared (IR) thermography. While optical sensors can provide real-time images of in-printing parts, they are unable to measure the thermal deviations essential to evaluate FFF process. Since IR sensors can provide thermal information of in-printing FFF parts with acceptable resolution in the spatiotemporal domain, these sensors can be utilized as an alternative source of information applicable for monitoring the print states and print defects of various types. In this study, an IR sensor-based data acquisition system is designed and integrated into an existing FFF printer to collect in-printing layer-wise real-time thermal data. As the FDM printer starts printing each layer of a part, the thermal data stream produced by the IR sensors from the in-printing part is collected along with the nozzle and the print bed temperature. By establishing a data-driven correlation of the spatiotemporal information between the non-defective and defective parts, a field-deployable approach to detect defects in real time is demonstrated herein.
Non-Linear Measurements of Roughness Effects in Pulsing Restricted Flows
Authors: Byers Clayton P. , Ofori Sandra , Chapata Lincoln , Ning Taikang 
Published: February 2024

Abstract
The influence of surface roughness on the acoustic spectrum in a pulsing restricted flow is investigated over a range of roughness sizes and flow conditions. Four different roughness scenarios are introduced, ranging from smooth to a relative roughness of 0.0486 based on hydraulic diameter. These span three different restriction severities ranging from moderate (56% restricted) to severe (82% restricted) based on the American Society of Echocardiography rating of aortic stenosis. The influence of restriction and roughness on the distribution of energy in the acoustic spectrum is evaluated, showing that enhanced roughness correlates with higher frequencies (150–300 Hz) becoming prominent in the spectrum. This trend follows with increasing restriction. As the Reynolds number changes, the spectral shape is not significantly affected, but the relative amount of energy in frequencies greater than 150 Hz does increase. A measure of frequency coupling is investigated by calculating the bicoherence for these cases, providing another quantitative assessment of the data. As more roughness is introduced, frequency coupling diminishes across all restrictions and Reynolds numbers. This new metric may provide a way of assessing the roughness of an internal flow through non-invasive means.
Assessment of the Thermal Comfort and CO2 Distribution Within a Movie Theatre
Authors: Costa Ana Carolina , Rodrigues Nelson , Carneiro Ana Marta , Teixeira Inês , Machado Lúcio Manuel , Ferreira Ana , Teixeira José , Teixeira Senhorinha 
Published: February 2024

Abstract
Human occupation is both the major source of pollutants and the main drive for providing a comfortable environment in buildings. Indoors, public buildings require special attention as they are used by a large number of people at the same time. The present work develops the application of a CFD (Computational Fluid Dynamics) model to simulate the thermal field and species distribution inside a movie theatre and to analyze the Indoor Air Quality (IAQ) to evaluate the thermal comfort of its occupants. For this movie theatre, the dimensions, the layout and the system ventilation details were obtained. The cinema was simulated at a ¾ capacity, while occupants were defined as heat, water vapor, and CO2 sources. People were distributed within the cinema by using the occupancy probability based on past records of ticket sales over a two-month period. Measurements also included the variables related to the thermal environment and the Predicted Mean Vote index. In addition to the thermal environment, the simulation included the release of CO2 through breathing. Based on the results, it was possible to conclude that the presence of people affects shows an increase of temperature, water vapor and CO2, mostly confined to the vicinity of the seats. Nevertheless, the actual ventilation system provided enough airflow for CO2 dispersion. The Predicted Mean Vote simulated overpredicted the experimental data, although by a small amount. Nonetheless, both values were below zero, indicating a cold sensation trend. Finally, it was verified that the flow rate at the inlet is within the parameters required by Portuguese legislation for the minimum flow rate of new air.
Teaching a Developed First-Year Flipped Classroom
Authors: Thamban P. L. Stephan , Fadda Dani , Rios Oziel 
Published: February 2024

Abstract
Teaching a mechanical engineering class for the first time requires significant preparation and content development. While a flipped classroom can be effective for student learning, course development can be quite difficult for the faculty. However, when a course is developed in a modular flipped classroom model, faculty, teaching the course for the first time, can benefit from the developed content. They can use and make improvements to modules based on their areas of expertise without affecting the entire course. The paper provides the perspective of a faculty member teaching a developed first year introduction to mechanical engineering course with the modular flipped classroom model.
Design, Prototyping, and Experiments Using Small-Scale Helical Drive Rover for Multi-Terrain Exploration
Authors: Vadlamannati Ashwin , Beknalkar Sumedh , Best Dustin , Bryant Matthew , Mazzoleni Andre 
Published: February 2024

Abstract
Rovers designed for polar exploration primarily operate in flat and arid central plateau of the Antarctic and are unsuitable for multi-terrain operation such as slushy slow, wet soil, open ice and open ocean. The Multi-terrain Amphibious ARCtic explOrer or MAARCO rover is a design concept that employs a pair of helical drives in order to traverse the diverse landscape of the Arctic for autonomous research missions. A small-scale prototype (3:10 scale) of the MAARCO rover was developed to test terrestrial motion. The prototype is a screw-propelled vehicle that has two helical drives (similar to Archimedes’ screw) actuated by two independent motors to employ a differential steering system.
The prototype performed several different maneuvers on a dry and wet sand — moving in a straight line, turning left, and turning right, and moving sideways by controlling the rotational speeds of the two drives. The sensors on the prototype collect data on angular orientation, linear acceleration and motor rotations.
Through the tests the rover provided critical insight into the dynamics of the MAARCO rover, particularly, the effect of substrate failure or non-failure on the linear displacement of the rover. Further testing on different substrates and of the rover design on inclines surfaces will provide the MAARCO team valuable insight into designing a full-scale rover design.
A Study on the Effect of Fiber Orientation on the Strength and Failure of 3D-Printed Carbon Fiber Reinforced Polymers
Authors: Kokner Yesim , Delpierre Arthur , Couzis Jason P. , Ardebili Mahmoud , Delale Feridun 
Published: February 2024

Abstract
The potential of 3D printed carbon composites as a material for advanced engineering applications was investigated by fabricating and testing of carbon fiber-reinforced composites using 3D printing technique. Three carbon fiber layups and a pure polymer were investigated. In the first configuration, the fibers were parallel to the direction of applied stress (0° orientation). In the second configuration, the fibers were perpendicular to the stress (90° orientation). In the third configuration, the fibers were orientated in diagonal pattern (± 45° orientation). The geometry of the test specimen was based ASTM D3039 protocol for testing composite materials. Compositional results indicated that the continuous carbon fiber filament used in the printer was composed of 39% carbon fibers. The specimens contained between 22–24% carbon fibers. Axial testing results indicated that the 90° fiber oriented specimen was the weakest, comparable or slightly weaker than the pure matrix specimen. The ±45° orientation of fiber improved the strength by a factor 3.5. The 0° oriented fiber reinforcement increased strength by a factor of 4 folds compared to ±45° orientation and about 22 folds compared to pure matrix or 90° orientation. The failure in the pure matrix, 90° and ±45° specimen occurred with clean fracture pattern in gauge section. The 0° sample failure occurred very close to the end taps portion with a great deal of delamination. The failure pattern for this configuration has led us to believe that its strength is even higher than that observed in the testing.