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Full-Text Articles in Mechanical Engineering

Advancements And Challenges In Additively Manufactured Functionally Graded Materials: A Comprehensive Review, Suhas Alkunte, Ismail Fidan, Vivekanand Naikwadi, Shamil Gudavasov, Mohammad Alshaikh Ali, Mushfig Mahmudov, Seymur Hasanov, Muralimohan Cheepu Jan 2024

Advancements And Challenges In Additively Manufactured Functionally Graded Materials: A Comprehensive Review, Suhas Alkunte, Ismail Fidan, Vivekanand Naikwadi, Shamil Gudavasov, Mohammad Alshaikh Ali, Mushfig Mahmudov, Seymur Hasanov, Muralimohan Cheepu

Engineering Technology Faculty Publications

This paper thoroughly examines the advancements and challenges in the field of additively manufactured Functionally Graded Materials (FGMs). It delves into conceptual approaches for FGM design, various manufacturing techniques, and the materials employed in their fabrication using additive manufacturing (AM) technologies. This paper explores the applications of FGMs in diverse fields, including structural engineering, automotive, biomedical engineering, soft robotics, electronics, 4D printing, and metamaterials. Critical issues and challenges associated with FGMs are meticulously analyzed, addressing concerns related to production and performance. Moreover, this paper forecasts future trends in FGM development, highlighting potential impacts on diverse industries. The concluding section summarizes …

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Energy Efficiency In Additive Manufacturing: Condensed Review, Ismail Fidan, Vivekanand Naikwadi, Suhas Alkunte, Roshan Mishra, Khalid Tantawi Jan 2024

Energy Efficiency In Additive Manufacturing: Condensed Review, Ismail Fidan, Vivekanand Naikwadi, Suhas Alkunte, Roshan Mishra, Khalid Tantawi

Engineering Technology Faculty Publications

Today, it is significant that the use of additive manufacturing (AM) has growing in almost every aspect of the daily life. A high number of sectors are adapting and implementing this revolutionary production technology in their domain to increase production volumes, reduce the cost of production, fabricate light weight and complex parts in a short period of time, and respond to the manufacturing needs of customers. It is clear that the AM technologies consume energy to complete the production tasks of each part. Therefore, it is imperative to know the impact of energy efficiency in order to economically and properly …

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Development Of A Two-Finger Haptic Robotic Hand With Novel Stiffness Detection And Impedance Control, Vahid Mohammadi, Ramin Shahbad, Mojtaba Hosseini, Mohammad Hossein Gholampour, Saeed Shiry Ghidary, Farshid Najafi, Ahad Behboodi Jan 2024

Development Of A Two-Finger Haptic Robotic Hand With Novel Stiffness Detection And Impedance Control, Vahid Mohammadi, Ramin Shahbad, Mojtaba Hosseini, Mohammad Hossein Gholampour, Saeed Shiry Ghidary, Farshid Najafi, Ahad Behboodi

Mechanical & Aerospace Engineering Faculty Publications

Haptic hands and grippers, designed to enable skillful object manipulation, are pivotal for high-precision interaction with environments. These technologies are particularly vital in fields such as minimally invasive surgery, where they enhance surgical accuracy and tactile feedback: in the development of advanced prosthetic limbs, offering users improved functionality and a more natural sense of touch, and within industrial automation and manufacturing, they contribute to more efficient, safe, and flexible production processes. This paper presents the development of a two-finger robotic hand that employs simple yet precise strategies to manipulate objects without damaging or dropping them. Our innovative approach fused force-sensitive …

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Mechanics Of Pure Bending And Eccentric Buckling In High-Strain Composite Structures, Jimesh D. Bhagatji, Oleksandr G. Kravchenko, Sharanabasaweshwara Asundi Jan 2024

Mechanics Of Pure Bending And Eccentric Buckling In High-Strain Composite Structures, Jimesh D. Bhagatji, Oleksandr G. Kravchenko, Sharanabasaweshwara Asundi

Mechanical & Aerospace Engineering Faculty Publications

To maximize the capabilities of nano- and micro-class satellites, which are limited by their size, weight, and power, advancements in deployable mechanisms with a high deployable surface area to packaging volume ratio are necessary. Without progress in understanding the mechanics of high-strain materials and structures, the development of compact deployable mechanisms for this class of satellites would be difficult. This paper presents fabrication, experimental testing, and progressive failure modeling to study the deformation of an ultra-thin composite beam. The research study examines the deformation modes of a post-deployed boom under repetitive pure bending loads using a four-point bending setup and …

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Parametric Optimization Of Friction Stir Welding Of Aa6061-T6 Samples Using The Copper Donor Stir-Assisted Material Method, Aiman H. Al-Allaq, Joseph Maniscalco, Srinivasa Naik Bhukya, Zhenhua Wu, Abdelmageed Elmustafa Jan 2024

Parametric Optimization Of Friction Stir Welding Of Aa6061-T6 Samples Using The Copper Donor Stir-Assisted Material Method, Aiman H. Al-Allaq, Joseph Maniscalco, Srinivasa Naik Bhukya, Zhenhua Wu, Abdelmageed Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

This study presents an optimization of the process parameters for the effect of copper (Cu) donor material percentage on the friction stir welding (FSW) of AA6061-T6 alloy. Extensive factorial experiments were conducted to determine the significance of the rotational speed (ω), the transverse speed (v), the interface coefficient of friction (μ), and the Cu donor material percentage in the plunge, left, right, and downstream zones. Design Expert 13 software was used to identify the number of simulation experiments to be conducted using the Abaqus simulation software. From Design Expert 13, which is a thorough multi-objective optimization analysis software, we were …

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Hardness Removal By A Continuous Flow Electrochemical Reactor From Different Types Of Water, Shahad Fadhil Alrubaye, Naseer A. Al Haboubi, Hussein A. Al-Amili, Aiman H. Al-Allaq, Dhuha Ahmed Mohammed Jan 2024

Hardness Removal By A Continuous Flow Electrochemical Reactor From Different Types Of Water, Shahad Fadhil Alrubaye, Naseer A. Al Haboubi, Hussein A. Al-Amili, Aiman H. Al-Allaq, Dhuha Ahmed Mohammed

Mechanical & Aerospace Engineering Faculty Publications

The present study focuses on the technique of hardness removal by using a novel reactor performing an electrocoagulation (EC) process. The variation of alkalinity is also recorded. Continuous flow experiments were conducted for Total Hardness (TH) removal using a transparent plastic reactor using aluminum plate electrodes that have holes so that the water flows through the plates in a zigzag way. The influence of various operating parameters such as the number of plates (two and four), flow rate (600, 1000 L/h), and water type (Tigris River & rejected water from Reverse Osmosis system RO) was investigated. The results showed that …

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Effect Of Post-Cured Through Thickness Reinforcement On Disbonding Behavior In Skin-Stringer Configuration, Jimesh D. Bhagatji, Christopher Morris, Yogaraja Sridhar, Bodhisatwa Bhattacharjee, Krishnanand N. Kaipa, Oleksandr G. Kravchenko Jan 2024

Effect Of Post-Cured Through Thickness Reinforcement On Disbonding Behavior In Skin-Stringer Configuration, Jimesh D. Bhagatji, Christopher Morris, Yogaraja Sridhar, Bodhisatwa Bhattacharjee, Krishnanand N. Kaipa, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

An experimental investigation of interlaminar toughness for post-cured through-thickness reinforcement (PTTR) skin-stringer sub-element is presented. The improvement in the crack resistance capability of skin-stringer samples was shown through experimental testing and finite element analysis (FEA) modeling. The performance of PTTR was evaluated on a pristine and initial-disbond of the skin-stringer specimen. A macro-scale pin-spring modeling approach was employed in FEA using a non-linear spring to capture the pin failure under the mixed-mode load. The experimental results showed a 15.5% and 20.9% increase in strength for the pristine-PTTR and initial-disbond PTTR specimens, respectively. The modeling approach accurately represents the overall structural …

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Effect Of Resin Bleed Out On Compaction Behavior Of The Fiber Tow Gap Region During Automated Fiber Placement Manufacturing, Von Clyde Jamora, Virginia Rauch, Sergii G. Kravchenko, Oleksandr G. Kravchenko Jan 2024

Effect Of Resin Bleed Out On Compaction Behavior Of The Fiber Tow Gap Region During Automated Fiber Placement Manufacturing, Von Clyde Jamora, Virginia Rauch, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Automated fiber placement is a state-of-the-art manufacturing method which allows for precise control over layup design. However, AFP results in irregular morphology due to fiber tow deposition induced features such as tow gaps and overlaps. Factors such as the squeeze flow and resin bleed out, combined with large non-linear deformation, lead to morphological variability. To understand these complex interacting phenomena, a coupled multiphysics finite element framework was developed to simulate the compaction behavior around fiber tow gap regions, which consists of coupled chemo-rheological and flow-compaction analysis. The compaction analysis incorporated a visco-hyperelastic constitutive model with anisotropic tensorial prepreg viscosity, which …

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Fabrication Of Smooth Sac305 Thin Film Via Magnetron Sputtering, M. Ojha, A. A. Elmustafa Jan 2024

Fabrication Of Smooth Sac305 Thin Film Via Magnetron Sputtering, M. Ojha, A. A. Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

SAC305 (96.5 wt% Sn, 3 wt% Ag, 0.5 wt%Cu) solder is increasingly becoming popular due to its reliability good characteristics and performance in addition to the environmental concerns and regulations that restrict the use of lead in nano/microelectronic products. In nano/microelectronics, manufacturing smooth solder coatings free of defects such as voids and cracks, which can compromise joint reliability is crucial. Magnetron sputtering offers a high degree of control over film thickness and composition, resulting in films with excellent uniformity and adhesion. Despite these advantages, fabricating continuous and robust SAC305 films using magnetron sputtering remains a difficult task with limited research …

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Parametric Study Of The Effect Of Increased Magnetic Field Exposure On Microalgae Chlorella Vulgaris Growth And Bioactive Compound Production, Sharanabasaweshwara Asundi, Sanurag Rout, Simone Stephen, Sanghamitra Khandual, Sandipan Dutta, Sandeep Kumar Jan 2024

Parametric Study Of The Effect Of Increased Magnetic Field Exposure On Microalgae Chlorella Vulgaris Growth And Bioactive Compound Production, Sharanabasaweshwara Asundi, Sanurag Rout, Simone Stephen, Sanghamitra Khandual, Sandipan Dutta, Sandeep Kumar

Mechanical & Aerospace Engineering Faculty Publications

This parametric study aimed to analyze the effects of increased magnetic field exposure (MFE) on the growth and production of the bioactive compounds of Chlorella (C.) vulgaris. With the intent of studying the effect of an increased MFE, the magnetic field typically experienced by life on Earth was amplified by an order of magnitude. In the increased-MFE environment, six treatments of C. vulgaris with two repetitions for each treatment were exposed to a magnetic field of 5 Gauss (500 µT) about each axis, which was generated in a state-of-the-art Helmholtz cage. The treatments and the control were characterized by the …

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Factors Affecting Electrocoagulation Process For Different Water Types: A Review, Shahad Fadhil Abed Al-Rubaye, Naseer A. Alhaboubi, Aiman H. Al-Allaq Jan 2024

Factors Affecting Electrocoagulation Process For Different Water Types: A Review, Shahad Fadhil Abed Al-Rubaye, Naseer A. Alhaboubi, Aiman H. Al-Allaq

Mechanical & Aerospace Engineering Faculty Publications

Raw water must meet specific physical, chemical, and biological requirements to be suitable for drinking. There are various techniques available for treating wastewater, and aside from conventional methods that involve chemicals, electrocoagulation is an efficient and advanced approach. Electrocoagulation has proven effective in treating many pollutants, including bacteria, viruses, iron, fluoride, sulfate, boron, hardness, and turbidity. Total suspended solids, organic and inorganic materials, chemical oxygen demand COD, biochemical oxygen demand BOD, and color. It finds extensive application in treating different types of water and wastewater due to its exceptional ability to remove diverse contaminants. Recently, electrocoagulation has garnered significant attention …

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Effects Of Electron Beam Irradiation On Crmnv And Crmntiv High Entropy Alloys: Nano-Mechanical, Structural, And Thermodynamic Perspectives, N. A. Sultana, Y. S. Mohammed, S. J. Pendleton, J. Vennekate, G. Ciovati, X. Li, H. Baumgart, A. A. Elmustafa Jan 2024

Effects Of Electron Beam Irradiation On Crmnv And Crmntiv High Entropy Alloys: Nano-Mechanical, Structural, And Thermodynamic Perspectives, N. A. Sultana, Y. S. Mohammed, S. J. Pendleton, J. Vennekate, G. Ciovati, X. Li, H. Baumgart, A. A. Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

Beam exit windows are crucial components of any particle accelerator as they provide an interface between the beamline vacuum and target material at atmospheric media. For high beam power machines, special materials and designs are required to withstand high radiation and mechanical loads, while minimizing energy loss during transition and maximizing window lifetime. This research investigates the impact of electron beam exposure to bulk CrMnV and CrMnTiV high entropy alloys (HEAs) with the primary goal of identifying suitable candidate materials for the design of robust and durable exit window settings. The selection criteria include intrinsic characteristics, power dissipation, and mechanical …

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Assessing Porosity Limit In Freeze-Cast Sintered Lithium Titanate (Li₄Ti₅O₁₂) Materials, Rohan Parai, Dipankar Ghosh Jan 2024

Assessing Porosity Limit In Freeze-Cast Sintered Lithium Titanate (Li₄Ti₅O₁₂) Materials, Rohan Parai, Dipankar Ghosh

Mechanical & Aerospace Engineering Faculty Publications

This study aims to assess the lower limit of porosity that can be achieved in freeze-cast sintered lithium titanate (LTO) materials while maintaining the characteristic pore directionality. LTO materials were fabricated with solid loading varying in the range of 30–37 vol.%. Sucrose and cationic dispersant were used to vary viscosity and total solute concentration in the aqueous LTO suspensions. Two series of suspension compositions were selected for freeze-casting. In one series, aqueous suspensions were prepared by mixing deionized (DI) water, sucrose, and LTO powder, while in the other series, aqueous suspensions were prepared by mixing DI water, sucrose, cationic dispersant …

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Restoration Of Strength In Polyamide Woven Glass Fiber Organosheets By Hot Pressing, Mohammad Nazmus Saquib, Edwing Chaparro-Chavez, Christopher Morris, Kuthan Çelebi, Diego Pedrazzoli, Mingfu Zhang, Sergii G. Kravchenko, Oleksandr G. Kravchenko Jan 2024

Restoration Of Strength In Polyamide Woven Glass Fiber Organosheets By Hot Pressing, Mohammad Nazmus Saquib, Edwing Chaparro-Chavez, Christopher Morris, Kuthan Çelebi, Diego Pedrazzoli, Mingfu Zhang, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Thermoplastic composite organosheets (OSs) are increasingly recognized as a viable solution for automotive and aerospace structures, offering a range of benefits including cost-effectiveness through high-rate production, lightweight design, impact resistance, formability, and recyclability. This study examines the impact response, post-impact strength evaluation, and hot-pressing repair effectiveness of woven glass fiber nylon composite OSs across varying impact energy levels. Experimental investigations involved subjecting composite specimens to impact at varying energy levels using a drop-tower test rig, followed by compression-after-impact (CAI) tests. The results underscore the exceptional damage tolerance and improved residual compressive strength of the OSs compared to traditional thermoset composites. …

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A Unit-Load Approach For Reliability-Based Design Optimization Of Linear Structures Under Random Loads And Boundary Conditions, Robert James Haupin, Gene Jean-Win Hou Aug 2023

A Unit-Load Approach For Reliability-Based Design Optimization Of Linear Structures Under Random Loads And Boundary Conditions, Robert James Haupin, Gene Jean-Win Hou

Mechanical & Aerospace Engineering Faculty Publications

The low order Taylor’s series expansion was employed in this study to estimate the reliability indices of the failure criteria for reliability-based design optimization of a linear static structure subjected to random loads and boundary conditions. By taking the advantage of the linear superposition principle, only a few analyses of the structure subjected to unit-loads are needed through the entire optimization process to produce acceptable results. Two structural examples are presented in this study to illustrate the effectiveness of the proposed approach for reliability-based design optimization: one deals with a truss structure subjected to random multiple point constraints, and the …

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Optimal Domain-Partitioning Algorithm For Real-Life Transportation Networks And Finite Element Meshes, Jimesh Bhagatji, Sharanabasaweshwara Asundi, Eric Thompson, Duc T. Nguyen Jun 2023

Optimal Domain-Partitioning Algorithm For Real-Life Transportation Networks And Finite Element Meshes, Jimesh Bhagatji, Sharanabasaweshwara Asundi, Eric Thompson, Duc T. Nguyen

Civil & Environmental Engineering Faculty Publications

For large-scale engineering problems, it has been generally accepted that domain-partitioning algorithms are highly desirable for general-purpose finite element analysis (FEA). This paper presents a heuristic numerical algorithm that can efficiently partition any transportation network (or any finite element mesh) into a specified number of subdomains (usually depending on the number of parallel processors available on a computer), which will result in “minimising the total number of system BOUNDARY nodes” (as a primary criterion) and achieve “balancing work loads” amongst the subdomains (as a secondary criterion). The proposed seven-step heuristic algorithm (with enhancement features) is based on engineering common sense …

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Gradient-Based Trade-Off Design For Engineering Applications, Lena A. Royster, Gene Hou Jun 2023

Gradient-Based Trade-Off Design For Engineering Applications, Lena A. Royster, Gene Hou

Mechanical & Aerospace Engineering Faculty Publications

The goal of the trade-off design method presented in this study is to achieve newly targeted performance requirements by modifying the current values of the design variables. The trade-off design problem is formulated in the framework of Sequential Quadratic Programming. The method is computationally efficient as it is gradient-based, which, however, requires the performance functions to be differentiable. A new equation to calculate the scale factor to control the size of the design variables is introduced in this study, which can ensure the new design achieves the targeted performance objective. Three formal approaches are developed in this study for trade-off …

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Jet Noise Reduction: A Fresh Start, Christopher K. Tam, Fang Q. Hu Jan 2023

Jet Noise Reduction: A Fresh Start, Christopher K. Tam, Fang Q. Hu

Mathematics & Statistics Faculty Publications

Attempts to reduce jet noise began some 70 years ago. In the literature, there have been many publications written on this topic. By now, it is common knowledge that jet noise consists of a number of components. They possess different spectral and radiation characteristics and are generated by different mechanisms. It appears then that one may aim at the suppression of the noise of a single component instead of trying to reduce jet noise overall. The objective of the present project is to reduce large turbulence structures noise. It is the most dominant noise component radiating in the downstream direction. …

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Thermotrophy Exploratory Study, James Weifu Lee Jan 2023

Thermotrophy Exploratory Study, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The question of whether environmental heat energy could be utilized as a source of energy for biological metabolism is the center of this exploratory research. In 1979, this author postulated a hypothesis for the existence of thermotrophs that could isothermally utilize environmental heat energy as a source of their energy on Earth. According to this hypothesis, the thermotrophs could be the first primitive forms of life in the early Earth environment. The chemotrophs and phototrophs that we currently are all well familiar with might have been evolved somehow from the primitive thermotrophs. Furthermore, all the organisms currently regarded as the …

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Post-Weld Heat Treatment Effects On Microstructure, Crystal Structure, And Mechanical Properties Of Donor Stir–Assisted Friction Stir Welding Material Of Aa6061-T6 Alloy, Aiman H. Al-Allaq, Manish Ojha, Yousuf S. Mohammed, Srinivasa N. Bhukya, Zhenhua Wu, Abdelmageed A. Elmustafa Jan 2023

Post-Weld Heat Treatment Effects On Microstructure, Crystal Structure, And Mechanical Properties Of Donor Stir–Assisted Friction Stir Welding Material Of Aa6061-T6 Alloy, Aiman H. Al-Allaq, Manish Ojha, Yousuf S. Mohammed, Srinivasa N. Bhukya, Zhenhua Wu, Abdelmageed A. Elmustafa

Mechanical & Aerospace Engineering Faculty Publications

Friction stir welding (FSW) technology combines heat input from friction and extreme plastic deformation to produce high-quality joints in aluminum and other alloy systems. This necessitates examining the final welded joint’s mechanical and structural properties. Post-weld heat-treated AA6061-T6 alloy that resulted from the application of a Cu donor stir–assisted (CDSA) friction stir welding (FSW) material was examined for crystal structure and mechanical properties. CDSA FSW samples were tested at a constant tool rotational speed of 1400 rpm and a welding translational speed of 1 mm/s. CDSA samples of 20% and 60% thickness of the AA6061-T6 base alloy were selected to …

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Exploring Additive Manufacturing In A Space Environment - A Capstone Design Project Experience, Zain Zafar Khan, Zachary Alan Sobelman, Sharanabasaweshwara Asundi Jan 2023

Exploring Additive Manufacturing In A Space Environment - A Capstone Design Project Experience, Zain Zafar Khan, Zachary Alan Sobelman, Sharanabasaweshwara Asundi

Mechanical & Aerospace Engineering Faculty Publications

The employment of additive manufacturing in the non-standard environments like space, ships, or submarines has the potential to be an advanced utility not only in the pre-flight production of aerospace components and structures, but also for the onboard manufacturing of components and tools necessary for future space missions. For example, the ability to produce tools and structural components on the International Space Station can provide the space community the opportunity to make repairs and upgrades to the space station without wasting time and resources transporting such materials through additional missions. Additive manufacturing would allow for space missions to use on …

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Topologically Optimized Electrodes For Electroosmotic Actuation, Jianwen Sun, Jianyu Zhang, Ce Guan, Teng Zhou, Shizhi Qian, Yongbo Deng Jan 2023

Topologically Optimized Electrodes For Electroosmotic Actuation, Jianwen Sun, Jianyu Zhang, Ce Guan, Teng Zhou, Shizhi Qian, Yongbo Deng

Mechanical & Aerospace Engineering Faculty Publications

Electroosmosis is one of the most used actuation mechanisms for the microfluidics in the current active lab-on-chip devices. It is generated on the induced charged microchannel walls in contact with an electrolyte solution. Electrode distribution plays the key role on providing the external electric field for electroosmosis, and determines the performance of electroosmotic microfluidics. Therefore, this paper proposes a topology optimization approach for the electrodes of electroosmotic microfluidics, where the electrode layout on the microchannel wall can be determined to achieve designer desired microfluidic performance. This topology optimization is carried out by implementing the interpolation of electric insulation and electric …

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Numerical Simulation Of The Donor-Assisted Stir Material For Friction Stir Welding Of Aluminum Alloys And Carbon Steel, Joseph Maniscalco, Abdelmageed A. Elmustafa, Srinivasa Bhukya, Zhenhua Wu Jan 2023

Numerical Simulation Of The Donor-Assisted Stir Material For Friction Stir Welding Of Aluminum Alloys And Carbon Steel, Joseph Maniscalco, Abdelmageed A. Elmustafa, Srinivasa Bhukya, Zhenhua Wu

Mechanical & Aerospace Engineering Faculty Publications

In this research effort, we explore the use of a donor material to help heat workpieces without wearing the tool or adding more heat than necessary to the system. The donor material would typically be a small piece (or pieces) of material, presumably of lower strength than the workpiece but with a comparable melting point. The donor, a sandwich material, is positioned between the tool head and the material to be welded, where the tool initially plunges and heats up in the same manner as the parent material that is intended for welding. The donor material heats up subsequent to …

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Effect Of Platelet Length And Stochastic Morphology On Flexural Behavior Of Prepreg Platelet Molded Composites, Siavash Sattar, Benjamin Beltran Laredo, Sergii G. Kravchenko, Oleksandr G. Kravchenko Jan 2023

Effect Of Platelet Length And Stochastic Morphology On Flexural Behavior Of Prepreg Platelet Molded Composites, Siavash Sattar, Benjamin Beltran Laredo, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Prepreg platelet molding compound (PPMC) can be used to create structural grade material with a heterogeneous mesoscale morphology. The present work considered various platelet lengths of the prepreg system IM7/8552 to study the effect of platelet length on the flexural behavior of PPMC composite. A progressive failure finite-element analysis was used to understand competing failure modes in PPMC with the different platelet length. The interlaminar and in-plane damage mechanisms were employed to describe complex failure modes within the mesostructure of PPMCs. Experimental results of the flexural tests of the PPMC with different platelet length sizes were used to validate the …

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Comparison Of Dynamics Stability Testing Techniques With Magnetic Suspension Wind Tunnel Capabilities, Otoniel A. Ramirez, Mark Schoenenberger, David E. Cox, Colin P. Britcher Jan 2023

Comparison Of Dynamics Stability Testing Techniques With Magnetic Suspension Wind Tunnel Capabilities, Otoniel A. Ramirez, Mark Schoenenberger, David E. Cox, Colin P. Britcher

Mechanical & Aerospace Engineering Faculty Publications

Dynamic stability testing techniques currently utilized at NASA Langley Research Center (LaRC) are conducted in multiple facilities and consists of free flight, forced oscillation, and free-to-oscillate tests. The NASA/ODU Magnetic Suspension and Balance System (MSBS) has been recommissioned to explore its utility as an additional facility to expand the dynamic stability test capabilities currently available at NASA LaRC. Simulations were created to replicate each current test facility and method as closely as possible. Data collected from the simulated environments was corrupted with replicated noise sources of the different testing environments and then compared to real data collected during tests when …

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A Review Of Piezoelectric Footwear Energy Harvesters: Principles, Methods, And Applications, Bingqi Zhao, Feng Qian, Alexander Hatfield, Lei Zuo, Tian-Bing Xu Jan 2023

A Review Of Piezoelectric Footwear Energy Harvesters: Principles, Methods, And Applications, Bingqi Zhao, Feng Qian, Alexander Hatfield, Lei Zuo, Tian-Bing Xu

Mechanical & Aerospace Engineering Faculty Publications

Over the last couple of decades, numerous piezoelectric footwear energy harvesters (PFEHs) have been reported in the literature. This paper reviews the principles, methods, and applications of PFEH technologies. First, the popular piezoelectric materials used and their properties for PEEHs are summarized. Then, the force interaction with the ground and dynamic energy distribution on the footprint as well as accelerations are analyzed and summarized to provide the baseline, constraints, potential, and limitations for PFEH design. Furthermore, the energy flow from human walking to the usable energy by the PFEHs and the methods to improve the energy conversion efficiency are presented. …

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Numerical Study Of The Time-Periodic Electroosmotic Flow Of Viscoelastic Fluid Through A Short Constriction Microchannel, Jianyu Ji, Shizhi Qian, Armani Marie Parker, Xiaoyu Zhang Jan 2023

Numerical Study Of The Time-Periodic Electroosmotic Flow Of Viscoelastic Fluid Through A Short Constriction Microchannel, Jianyu Ji, Shizhi Qian, Armani Marie Parker, Xiaoyu Zhang

Mechanical & Aerospace Engineering Faculty Publications

Electroosmotic flow (EOF) is of utmost significance due to its numerous practical uses in controlling flow at micro/nanoscales. In the present study, the time-periodic EOF of a viscoelastic fluid is statistically analyzed using a short 10:1 constriction microfluidic channel joining two reservoirs on either side. The flow is modeled using the Oldroyd-B (OB) model and the Poisson-Boltzmann model. The EOF of a highly concentrated polyacrylamide (PAA) aqueous solution is investigated under the combined effects of an alternating current (AC) electric field and a direct current (DC) electric field. Power-law degradation is visible in the energy spectra of the velocity fluctuations …

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Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali Jan 2023

Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

A seawater reverse osmosis (RO) plant layout based on multistage RO with stages located at different elevations above sea level is described. The plant uses the weight of a seawater column from pumped storage as head pressure for RO (gravity-driven multistage RO) or to supplement high-pressure pumps used in RO (gravity-assisted multistage RO). The use of gravitational force reduces the specific energy for RO compared to using high-pressure pumps. By locating the RO stages at different elevations based on demand sites, the total specific energy consumption for RO and permeate transport to different elevations above sea level is reduced from …

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Using Strategic Options Development And Analysis (Soda) To Understand The Simulation Accessibility Problem, Andrew J. Collins, Ying Thaviphoke, Antuela A. Tako Nov 2022

Using Strategic Options Development And Analysis (Soda) To Understand The Simulation Accessibility Problem, Andrew J. Collins, Ying Thaviphoke, Antuela A. Tako

Engineering Management & Systems Engineering Faculty Publications

Simulation modelling is applied to a wide range of problems, including defense and healthcare. However, there is a concern within the simulation community that there is a limited use and implementation of simulation studies in practice. This suggests that despite its benefits, simulation may not be reaching its potential in making a real-world impact. The main reason for this could be that simulation tools are not widely accessible in industry. In this paper, we investigate the issues that affect simulation modelling accessibility through a workshop with simulation practitioners. We use Strategic Options Development and Analysis (SODA), a problem-structuring approach that …

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Smart Manufacturing—Theories, Methods, And Applications, Zhuming Bi, Lida Xu, Puren Ouyang Aug 2022

Smart Manufacturing—Theories, Methods, And Applications, Zhuming Bi, Lida Xu, Puren Ouyang

Information Technology & Decision Sciences Faculty Publications

(First paragraph) Smart manufacturing (SM) distinguishes itself from other system paradigms by introducing ‘smartness’ as a measure to a manufacturing system; however, researchers in different domains have different expectations of system smartness from their own perspectives. In this Special Issue (SI), SM refers to a system paradigm where digital technologies are deployed to enhance system smartness by (1) empowering physical resources in production, (2) utilizing virtual and dynamic assets over the internet to expand system capabilities, (3) supporting data-driven decision making at all domains and levels of businesses, or (4) reconfiguring systems to adapt changes and uncertainties in dynamic environments. …

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