bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal Orbital Spacecraft Analysis of an Additively Manufactured Deployable Radiator Oscillating Heat Pipes (AMDROHP) CubeSat
Authors: Miesner Spencer , Shibata Gabriella , Bautista Neyda , Wolk Kieran , Furst Ben , Daimaru Takuro , Sunada Eric , Roberts Scott , Bellardo John , Kuo Jim 
Published: February 2024

Abstract
As small spacecraft technologies develop, thermal management devices need to meet the growing demands of high-powered electronics. Currently being developed to meet this demand in CubeSats is the Additively Manufactured Deployable Radiator Oscillating Heat Pipes (AMDROHP). AMDROHP seeks to implement the high thermal conductivity and two-phase technology of Oscillating Heat Pipes into a unique deployable radiator design for a 3U CubeSat, taking advantage of additive manufacturing capabilities. While much consideration has been put into designing the AMDROHP on its own as a heat exchanger, there is also the need for it to be evaluated thermally at a system-level with the rest of the CubeSat while in orbit. In this study, thermal orbital spacecraft simulations, through the Thermal Desktop software, were performed to analyze how AMDROHP thermally integrates and interacts with the rest of the CubeSat and evaluate the survivability of temperature-sensitive components on the spacecraft. The simulations in this study included an 11th-orbit beta angle sweep for a tumbling orientation of the spacecraft in Low Earth Orbit (LEO). These simulations were performed with two AMDROHP devices in the CubeSat bus, each under a direct 25W heat input and performing with a thermal conductance of 6 W/K, which corresponds to the projected performance of the AMDROHP device while in operation. In this paper, the Thermal Desktop model of the AMDROHP CubeSat includes all major physical components, connections, heat loads, and thermal and optical materials. Then, steps are taken to improve the computational speed of the model. Furthermore, the means of addressing the modeling of the complex two-phase behavior of the OHP is outlined. Then, a number of test cases considering various operating conditions were simulated. From these simulations, orbital temperatures of sensitive components, primarily electronics, were collected and analyzed to find the minimum and maximum operating temperatures across all potential orbits. These temperatures were then evaluated to determine the component’s survivability in a worst-case scenario in orbit. From the results, it was found that, with the projected conductance of AMDROHP, all components operate under safe temperature conditions for any beta angle while in Low Earth Orbit. The evaporator is consistently the hottest component of the spacecraft and electronics boards all maintain survivable temperatures and are not at risk of over or underheating, even at worst case temperatures for all orbits tested. Based on the results and analysis of this conceptual study, it is suggested that AMDROHP will perform as an effective management device for small satellites.
Numerical Investigation of Steady Blowing on Active Drag Reduction of a Truck Model
Authors: Zhang Cheng , Ge Haiwen , Bakhoum Ezzat 
Published: February 2024

Abstract
Large trucks are an important way of transporting goods worldwide. Aerodynamic drag is responsible for a large portion of the energy consumption in trucks, hence there are increasing interests in reducing the aerodynamic drag to achieve better fuel efficiency. Many active and passive flow control strategies have been proposed to reduce the aerodynamic drag of trucks. The effects of steady blowing on drag reduction of the Ground Transportation System (GTS) truck model are studied using an Improved Delayed Detached Eddy Simulation (IDDES) model, with a Shear Stress Transport (SST) k-ω model in the boundary layer. A bounded central difference scheme is used for the momentum equation, and a second-order upwind scheme is used for the k and ω equations. A bounded second order implicit scheme is used for time marching. For the baseline case, the predicted pressure coefficient and drag coefficient are in good agreement with the experimental data. The locations of the vortices in the wake along a vertical streamwise cut and a horizontal stream-wise cut are also in reasonable agreement with the experimental data. In addition to the baseline case, cases with steady blowing introduced from four slots at the edges of the truck base are also considered. The blowing velocities have a component in the streamwise direction, and another component perpendicular to the streamwise direction and pointing to the center of the truck base, forming a 45° angle with the streamwise direction. Cases with three different blowing velocity magnitudes (10m/s, 50m/s, and 100m/s) are reported. It has been found that the length of the recirculation zone, as well as the locations and sizes of the vortices in the wake have changed due to steady blowing for the 50m/s and 100m/s cases. Compared to the baseline case, cases with steady blowing velocity magnitudes of 10m/s, 50m/s, and 100m/s have a drag reduction of 2.41%, 8.84%, and 9.24%, respectively. However, taking into account the power consumed to produce the steady blowing, the blowing efficiency for the three cases are 2.40%, 7.34%, and −2.76%, respectively. Among the three cases considered here, the 50m/s case is the most efficient in reducing the aerodynamic drag. On the other hand, the 100m/s case actually increases power consumption by 2.76%.
A Study on Surface Texture and Wettability of Femtosecond Laser Treated Aluminum Alloy
Authors: Angell Dakota , Wang Xinya , Song Xiaoxu , Lei Shuting 
Published: February 2024

Abstract
This study aims to investigate the effects of femtosecond laser treatment on surface texture and wettability properties of an aluminum alloy, AL6061, with the primary goal of creating a superhydrophobic surface. A central composite design is used for the laser surface texturing design of experiments. Surface texture is examined using SEM to detect minuscule changes on the morphology. A 3D optical profiler extracts topographical data from the surface. A contact angle goniometer based on the sessile drop method is used to measure the contact angle of the textured samples. The response surface method is used to build a second-order polynomial model for the contact angle and obtain optimal parameters to maximize the contact angle. This research shows that laser surface texturing can generate a wide range of surface profiles and roughness values with geometric features ranging from hundreds of μm to submicron. All three laser parameters (pulse energy, pulse duration, pulse repetition rate) affect surface roughness and contact angle to some degree. To quantify the relationship between the contact angle and laser parameters, a response surface model for Al6061 is identified and used to find the optimal conditions of E = 214 μJ, tp = 10 ps, and fp = 2427 Hz with a predicted maximum contact angle of 161°. A confirmation experiment produces a contact angle of 168°, in good agreement with the predicted value.
Spin Forming Simulation and Forming Defect Analysis of Thin-Walled Deep Conical Parts
Authors: Zheng Jiabin , Shu Xuedao , Lu Qinying , Li Zixuan , Xu Haijie , Len Junkun 
Published: February 2024

Abstract
Aluminum alloy is widely used in various thin-walled deep conical parts due to its strong corrosion resistance, high specific strength and good plasticity. In this paper, the deep cone 1100 aluminum alloy parts are spun by the preform scheme. This scheme combines the advantages of multi-pass stamping and spinning, and can reduce the number of spinning passes of deep cone parts to four passes, which significantly improves the production efficiency. In this paper, Simufact software is used for simulation experiments. Different spinning schemes and different spinning parameters are imported into finite element software for simulation analysis, and finally different simulation results are obtained. The results show that for the workpiece on the preform, it is feasible to use the scheme of one-pass die-fitting spinning. In the spin forming of the final die, if the scheme of single pass die forming is adopted, the waist of the workpiece has the risk of cracking, and the wall thickness distribution of the whole workpiece is uneven. The final product is formed by four passes spinning, and the wall thickness of the product is uniform and the quality is reliable. This paper provides a new processing scheme for the actual production of thin-walled deep tapered aluminum alloy parts, which can effectively solve the problems of many molds in stamping forming and complex roller trajectory in spin forming, and significantly improve the production efficiency.
Smart Patterning for Topological Pumping of Elastic Surface Waves
Authors: Wang Shaoyun , Hu Zhou , Wu Qian , Zhu Rui , Huang Guoliang 
Published: February 2024

Abstract
Topological pumping supplies a robust mechanism to steer waves across a sample without being affected by disorders and defects. For the first time, we demonstrate the pumping of elastic surface waves, achieved by a smart patterning of a surface that creates a synthetic dimension, which is explored by the wave as it is launched perpendicularly to the steering direction. Specifically, we design and fabricate an elastic medium decorated with arrays of pillar-type resonators whose eigenmodes are located below the sound cone, together with coupling bridges edged according to a specific algorithm. We establish a connection between the collective dynamics of the pillars and that of electrons in a magnetic field by deriving an accurate tight-binding model and developing a WKB-type analysis suitable for such discrete aperiodic systems with spatially slow-varying couplings. This enables us to predict topological pumping pattern, which is numerically and experimentally demonstrated by steering waves from one edge of the system to the other. Finally, the immune character of the topologically pumped surface waves against disorder and defects is evidenced. The principle of surface patterning together with the WKB-analysis could provide a powerful new platform for surface wave control and exploration of topological matter in higher dimensions.
PVC-Based Materials for Thermoformed Tactile Diagrams: Assessment and Characterization
Authors: S. Ganesh , Ahuja Ramya , Goel Priyank , Sapra Pulkit , Rao P. V. Madhusudhan 
Published: February 2024

Abstract
Tactile diagrams are embossed diagrams on a sheet that visually challenged people explore through touch. One of the common processes to prepare these diagrams is by vacuum thermoforming. These diagrams help non-sighted people to explore pictorial contents such as maps, books, charts, and artworks. The identification of suitable and affordable polymeric material for preparing thermoformed tactile diagrams has not been explored much by researchers. The present research attempts to investigate alternate material for this purpose which meets three essential requirements: affordability, manufacturability, and perceptibility. Four different Polyvinyl Chloride (PVC) -based materials have been selected and studied as a part of this work. Initial studies show that PVC-based materials are more suitable for tactile diagrams because of their cost, low density, and, more importantly, stretchability at higher temperatures. All four materials are characterized using techniques such as Fourier-transform infrared spectroscopy (FTIR), Thermo-gravimetric analysis (TGA), and Differential scanning calorimetry (DSC) to know the exact compositions of materials. Characterization studies show that an essential ingredient, namely PVC content, typically varied from 70% to 90%. All the substrates were used to prepare tactile diagrams by thermoforming and to conduct user feedback experiments to study the readability, clarity of edges, sheet quality, and surface finish. The study carried out as a part of this work demonstrates that thermoforming of tactile diagrams may be carried out successfully on all four substrates with some limited number of adjustments in processibility to accommodate for the differences in these materials. These new materials will facilitate the production of thermoformed diagrams in an affordable manner and make them available to a large population of visually challenged.
Influence of Heat Treatment on the Microstructural Properties of Wire Arc Additively Manufactured Inconel 625 Alloy
Authors: Thangapandian N. , Manivannan R. , Shanmugam Ragavanantham , Vivekananda A. S. , Rangarajan V. 
Published: February 2024

Abstract
In this research, Wire arc additively manufactured IN625 alloy was subjected to different heat treatments and compared with the unheated alloy. All three samples were solution treated to a temperature of 980 °C followed by furnace cooling. S1 and S2 denote the solution-treated sample with a soaking period of 30 min and 1 hour respectively, whereas, S4 represents the sample which is aged for 8 hours at 720 °C respectively after the 1-hour solution treatment. The columnar and dendritic structures were visible in the parent additively manufactured (S1) specimen. These structures cannot be seen in the wire, which is used as the feed material for WAAM. The microstructure of the solution heat-treated specimen (S2) was seen with clear grain boundaries and precipitates. The micrograph confirms the uniform grain structure and more dispersed precipitates when compared to the unheated specimen. Though the average grain size remains the same, there were visible coarse grains in the 1-hour aged sample when compared to the 30-minute aged sample. The microhardness of the different heat-treated samples was measured using a Rockwell hardness tester to study the influence of heat treatment. The results revealed that the heat treatment significantly improved the hardness of the specimen.
Waterjet Process Parameters Optimization
Authors: Alsayyed Basel , Malm Frederick O. 
Published: February 2024

Abstract
Abrasive Water Jet Machining (AWJM) is a non-conventional machining process widely used in modern manufacturing industries due to its versatile cutting capabilities. The optimal performance of AWJM depends on the appropriate selection of process input parameters, which include water pressure, abrasive mass flow rate, material thickness, and cutting feed. However, the impact of material thickness variation on the AWJM process has been overlooked in previous research studies. To address this research gap, this study aims to investigate the effect of material thickness variation on the performance of AWJM and incorporate it as a factor in the process input parameters. The study methodology will employ the Taguchi orthogonal array and Analysis of Variance (ANOVA) to determine the optimal levels of process parameters for aluminum 6061 T65. The Design of Experiment (DoE) model will be set up based on the four input factors and their levels. Experiments will be conducted using the A-0612 WARDJet machine to achieve the best quality characteristics regarding the material removal rate (MMR) and the surface roughness Ra for different materials. By considering material thickness as a factor in the analysis of responses, this study seeks to enhance the understanding of the interrelationship between process input parameters and material thickness variation in AWJM. The study findings are expected to provide valuable insights to improve process efficiency and effectiveness, leading to better-quality outcomes in modern manufacturing industries.
Parameter Analysis of Spherical Pulsation Damper Using ANSYS Fluid-Solid Interaction
Authors: Butler Finnley , Duan Shawn 
Published: February 2024

Abstract
Various devices have been developed for the reduction of pulsation-induced vibrations, such as diaphragm chamber systems or gas bladders, non-intrusive fluid wave actuators and fluid filled, also known as reflection-type, dampeners. However, these devices are not suitable in a hydraulic system powered by a triplet piston pump. For example, pulsation dampeners incorporating gas bladders are effective, but there are many drawbacks. Loss of gas charge, incorrect gas charge or volume/mass ratio, elastomeric rupture, narrow range of pressure operation and pump speeds, routine maintenance, ineffective location, and branch connection instead of in-line configuration are all integrity issues which the industry faces. In addition to having a structural integrity issue, branch connected devices do not perform as efficiently as in-line devices. If a pulsation dampener is responsible for safeguarding critical equipment or systems, premature rupture of a gas bladder can be catastrophic.
This paper introduces a spherical pulsation dampener which is used to reduce harmful pulsations induced by a triplet piston pump in fluid power systems. The damper is composed of an inlet, a distributing plate with nozzles, a spherical housing, a receiving plate with orifices, and an outlet. The damper can be welded in-line and reduce 75% of pulsation-induced vibrations. The paper presents how fluid-solid interaction (FSI) and transient structural modules of ANSYS will be used to model and simulate the spherical pulsation damper. Developing a compatible system coupling module is necessary to generate models cognizant of time and computing expenditure. The preparatory build model is used to study mechanisms of pulsation reduction in the spherical damper and to analyze the correspondence of key damper parameters to the effectiveness of pulsation reduction. A CAD model of the pulsation damper is built in Autodesk Inventor, with a control volume of the fluid in the damper indicative of proper boundary condition. The model will then be imported into ANSYS, with fluid-solid interaction and transient structural modules, to study fluid flow fields and understand the governing mechanisms for reducing the pulsation induced by a triplet piston pump. Furthermore, a study will be carried out to analyze how the design of key parameters, such as the diameters of the inlet and the outlet nozzles, the axial distance between the distribution plate and the receiving plate, and the radius of the spherical housing, experience fundamental repercussions in pulsation reduction. The results of this work will be partially useful for engineers to design an efficient spherical pulsation damper, and supplement individual requirements to match up a triplet piston pump with a spherical pulsation damper effectively.
Development of Interactive Teaching Aid Material for Engineering Courses
Authors: Higby Dustin , Pashah Sulaman 
Published: February 2024

Abstract
Teachers’ clarity is the most essential factor in student learning. In addition to the teaching approach, teaching material is necessary for clearly presenting complicated engineering topics. Smart classrooms with multimedia support are conducive to covering complex engineering topics in less time. Nevertheless, the graphics are generally in static image format (from textbook publishers as instructor resources). Therefore, the entire image is displayed with a single click. Despite being time effective, this approach is not helpful from a student’s learning point of view because the essence of developing the concept from scratch is lost. PowerPoint provides various graphic and visual tools to develop detailed graphical illustrations using simple drawing objects and animation tools. Converting an image into a combination of drawing objects has the advantage of creating the illustration from scratch using animation tools stepwise rather than displaying the entire image at once. The other benefits include using multi-colors for improved visuals and a better understanding of a complicated graphical illustration or concept. Nonetheless, two-dimensional illustrations cannot represent three-dimensional configurations and motion simulations. This issue can be addressed by interactive three-dimensional illustrations and carefully planned motion animations. The illustrations are, however, not readily available and must be developed by the instructor. Development of interactive illustrations and animations requires considerable time and effort, in addition to knowledge of the software to be used to create such material. This work presents interactive illustrations for an enhanced learning experience for mechanical engineering courses at Texas A&M University Texarkana.
Stochastic Stability of a Torsional-Flutter Energy Harvester in Thunderstorm-Like Winds: Duffing vs. Hybrid Duffing – Van Der Pol Restoring Force Mechanisms
Authors: Caracoglia Luca 
Published: February 2024

Abstract
Wind energy harvesters are usually designed to operate in the low wind speed range and for medium scale applications, as a complement to standard, large horizontal-axis wind turbines. A torsional-flutter-based apparatus has been proposed by the author to extract wind energy. The apparatus is composed of a non-deformable, flapping blade-airfoil. A nonlinear torsional spring mechanism (Duffing model), installed at equally spaced supports, enables limit-cycle, post-critical vibration.
In this study a new model is proposed by replacing the Duffing restoring force mechanism by a hybrid Duffing – van-der-Pol one that couples a cubic torsional spring with amplitude-dependent damping. The apparatus is designed to be used in an area where thunderstorm-like flows may be present. The flow model accounts for both non-stationary turbulence and a slowly varying mean outflow, replicating intensification and decay of a thunderstorm.
Mean-square stability is studied through Moment Lyapunov Exponents. Stability limits are computed numerically through Monte Carlo solution of the numerical model. Various configurations are examined.
Variable Radius Fillet Shape Analysis to Minimize Stress Concentration Effects: Learning From Trees for Sustainable Design
Authors: Warner Mark , Vargas-Silva Gustavo , Jawaharlal Mariappan 
Published: February 2024

Abstract
Abrupt changes in geometry create stress concentrations, which are highly localized stresses causing failure at these locations. Engineers create fillets, and round-off sharp corners to reduce these stresses. Stress concentrations occur in the natural world, and the objective of this paper is to understand how trees handle areas of high stresses, learn from nature, and are used for engineering design inspiration. The main areas of the tree where high stress concentration occurs are the trunk base, where the trunk meets the ground above surface, and the branch base, where tree branches intersect with the trunk. Although extensive work has been done on the trunk base of trees, little work has been done on the branch base.
In this paper, the effectiveness of the natural curvature where branches intersect with the trunk is analyzed. The tree used in this scheme comes from the species Pinus Taeda (a.k.a. Loblolly Pine). The natural tree fillet was compared with both circular fillets and shapes developed using the Method of Tensile Triangles, a graphical way to create an optimized fillet design in nature. The comparison was carried out by using Finite Element Method (FEM). Static bending studies were done on both 2D and 3D models comparing various fillet geometries and stresses.