Mechanical Engineering Commons^™

A Provable Semi-Infinite Programming Approach For Solving Dynamic Nash Games, Tyler C. Gardner

All Graduate Theses and Dissertations, Fall 2023 to Present

Many engineering problems must account for the non-cooperative decisions and actions of multiple players. These problems can be modeled within a game-theoretic framework. The approach herein is to model problems as Nash games, convert them to semi-infinite programs, and leverage provable semi-infinite algorithms to solve the original problem. A particular algorithm that leverages off-the-shelf solvers is used to solve four low-dimensional benchmark problems successfully. Two types of linear quadratic dynamic games are then investigated: ones where each player’s problem is convex and ones where at least one player’s problem is nonconvex. Within each type, variations based on information structure, communication …

An Optimization Study Of Multi-Orifice Synthetic Jets, Rhett T. Parry

All Graduate Theses and Dissertations, Fall 2023 to Present

From the mixing of creamer into coffee, to the dynamics of a dust storm, or smoke rising from a chimney—everything is driven by turbulent fluid motion. Experimentalists bring the complex driving mechanism that is turbulence into a laboratory setting to fundamentally understand its behavior in response to certain test parameters. Researchers may choose various drivers, or “actuators”, of fluid motion to start the turbulent regime for their applications. However, in building an entire experimental apparatus, they miss the step of ensuring that an individual driver is performing as best as possible. A common actuator used in experimental studies is a …

Analysis Of Thrust Performance And Noise Generation Of Uam Composite Propellers Fabricated Using Composite-Based Additive Manufacturing, Samiul Alam

All Graduate Theses and Dissertations, Fall 2023 to Present

Urban air mobility (UAM) is an emerging transportation concept that uses lightweight, efficient aircraft for transporting goods and passengers and performing other logistical activities. One of the biggest challenges in developing UAM from a structural perspective is manufacturing strong and reliable propellers that are lightweight and durable. Traditional manufacturing methods for composite propellers are expensive, time-consuming, and difficult to scale. This study explores a new approach using Composite-Based Additive Manufacturing (CBAM) to produce high-performance propellers more efficiently. CBAM allows for the fabrication of strong, lightweight composite propellers using short manufacturing lead times. However, one challenge with this technique is that …

Advancing Real-World Implementation Of The Well Optimized Linear Finder (Wolf) High-Speed Atmospheric Turbulence Compensation Method, Timothy Evan Coon

Theses and Dissertations

This dissertation advances the real-world implementation of the Well Optimized Linear Finder (WOLF) method for high-speed Atmospheric Turbulence Compensation (ATC). Atmospheric turbulence introduces phase aberrations into optical wavefronts and degrades image quality in terrestrial imaging systems. Traditional phase diversity methods are computationally intensive and poorly suited to real-time operation. The WOLF method addresses these limitations through a novel, point-wise formulation of the optical transfer function (OTF) as a structured autocorrelation of the generalized pupil function (GPF). This formulation enables the estimation of phase aberrations at individual spatial coordinates with distributed computational complexity.

The research begins by developing a MATLAB-based simulation …

Impact Of Humidity From Shrink (Wrap) Tunnels On Refrigeration Systems: Comparing Economic And Environmental Impact Of Natural Gas And Electric, Segun Samuel Oladipo

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis examines the economic and environmental effects of electric and steam shrink-wrapping tunnels used in beef packaging processes, paying particular attention to the indirect refrigeration loads caused by the heat and humidity that each system releases. Traditional sustainability evaluations frequently ignore these indirect impacts, which are especially important in meat processing facilities where 45–55% of electricity use is attributed to refrigeration. Life cycle assessment (LCA), field measurements, and thermodynamic modeling are all used in this work to offer a thorough analysis of both tunnel types.

The case study facility in Nebraska operates both steam and electric shrink tunnels to …

3d Printing Of Short Fiber Reinforced Polypropylene: Novel Lattice Architecture And Material Characterization, Mohammad Ghazi Alshneeqat

Theses

This study explores the enhanced compressive behavior of 3D-printed single and double gyroid solid-networks lattices. Where the double gyroids are constructed from two intertwined single gyroid structures. These structures were designed by nTop implicit modeling tool and then fabricated by material extrusion additive manufacturing method at optimized printing parameters, including optimized nozzle temperature and raster angle. The main objective of this study is to reveal the compressive behavior of the novel double gyroid lattice structure and then to tailor its response through variable gyroid heights. Standard polymer tests were performed, considering thermogravimetric analysis, to confirm the thermal stability of the …

Effect Of Moderate Decrease In Contractility On Epithelial Cell-Cell Contacts Under External Stretch, Saika Sharmin

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial tissues are characterized by extensive cell–cell contacts and often subject to stretch during normal function. Cell-cell contact adhesion strength maintains mechanical continuity from cell to cell. Mechanical forces exerted by cells via actomyosin contractility are known to strengthen cell-cell adhesions to a certain extent. While it is known that a large decrease in contractility causes cell-cell contact rupture due to weakened adhesions, it is unclear how a moderate reduction in contractility affects cell-cell junction stability. Here, we studied how a moderate inhibition of non-muscle myosin II (NMII) affects the integrity of epithelial cell-cell contacts, especially when subject to the …

Towards Improving Computational Modeling Of The Lumbar Spine - Impact Of Material Properties And Laminotomy On Spinal Biomechanics, Isaac K. Kumi

Mechanical & Aerospace Engineering Theses & Dissertations

Spinal ligaments play a crucial role in maintaining the mechanical stability of the lumbar spine. These dense, collagenous tissues not only resist excessive motion but also distribute loads between spinal components to protect neural structures. Traditionally, the mechanical response of ligaments has been modeled using linear elastic assumptions, which treat the tissue as having a constant stiffness regardless of loading history. While this simplifies analysis, it fails to capture the time-dependent behaviors, such as creep, stress relaxation, and hysteresis, that are characteristic of biological tissues.

Viscoelastic modeling may provide a more physiologically accurate representation by incorporating both elastic and viscous …

Impact Of Non-Uniform Surface Temperature On The Apparent Radiative Properties Of Cavity Receivers, Ehsan Mofidipour, Matthew R. Jones, Brian D. Iverson

Faculty Publications

Radiative surface properties play a critical role in the design, analysis and optimization of solar–thermal systems. Cavity receivers increase the efficiency of solar–thermal energy systems through the cavity effect. The cavity effect refers to increased absorption of radiation due to multiple reflections within a cavity. Apparent radiative surface properties of a cavity characterize the effective interactions of radiation passing through an imaginary surface covering the cavity aperture. In this study, we investigate the extent to which the apparent emissivity of a cavity with a non-uniform surface temperature profile may be estimated using an isothermal enclosure model. A cylindrical cavity was …

Inter-Cellular Forces Modulate Cell-Ecm Traction Forces, Zaria Booth

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial cells are among the most abundant cell types in the human body, making up sheets of epithelial tissues that cover the linings of organs and body cavities. Cellular adhesion and force transmission across epithelial tissues are crucial in maintaining tissue integrity and ensuring proper tissue regeneration. Defects in cellular force transmission have been found in various diseases, including cancer. Force transmission at cell-cell and cell-ECM junctions drive cell survival and development. It has been previously shown that changes in cell-ECM traction directly modulates forces at cell-cell contacts. In this study, we aim to determine the effects of perturbations in …

Tribology Of Textured Surfaces, Min Zou, Mahyar Afshar-Mohajer, Robert A. Fleming

Mechanical Engineering Faculty Publications and Presentations

Surface texturing has emerged as a transformative approach to improving friction, lubrication, and wear across a wide range of mechanical components. From bio-inspired micro-dimples to engineered macro-grooves, texture designs are increasingly applied in biomedical implants, bearings, seals, and automotive systems. This Special Issue, “Tribology of Textured Surfaces,” compiles 14 papers that collectively cover fabrication techniques, multi-scale optimization, predictive modeling, and diverse application areas.   The following sections summarize the major themes of this Special Issue. Section 2 reviews the fabrication techniques and texture scales addressed by the authors. Section 3 examines modeling and numerical studies, while Section 4 categorizes the work …

Is There A More Effective Design For Quadrat To Increase Ease Of Use And Vegetation Density?, Scott M. Burke Jr., Kristen M Bellisario

Discovery Undergraduate Interdisciplinary Research Internship

Quadrats are a special tool in the ecology field that allows the measurement of vegetation density for further data analysis of a habitat. The larger the quadrat cross-sectional area, the better the results of the data, which in turn can make the quadrat hard to carry through field sites. In wildlife corridor research, quadrat surveys provide a quantitative metric for habitat suitability. In this work, we consider the efficiency and ease-of-use benefits for field work in the design of a collapsible version of a quadrat using a House of Quality (standard metric for new design requirements) to assess the customer …

Development Of Power Management On Unmanned Surface Vehicles To Measure Battery Voltage And Power, Diana Alia, Henna Nurdiansari, Akhmad Kasan Gupron, Amelia Greacy Talenta Siregar

Journal of Mechanical Engineering Science and Technology (JMEST)

This research focuses on designing an electrical system for unmanned surface vehicles (USV) to ensure optimal performance during survey operations. This USV ship is a catamaran-type ship with a Sonar Deeper depth sensor to know the depth of the water and is equipped with long range (LoRa) as a data transmitter. The USV electrical system design incorporates the use of a 4050 mAh 11.1 V LiPo battery and an iMAX B6AC charger, with evaluations covering battery charging, power consumption, and voltage stability. The trials showed that the battery supported the operation of the USV for approximately 47.8 minutes at a …

Utilization Of Biomass From Kerai Payung Trees And Waste Paper Through Pyrolysis Technology To Support The Zero-Waste Concept, Anggita Putri Indadari, Nurfa Anisa, Asih Budi Santoso

Journal of Mechanical Engineering Science and Technology (JMEST)

Wisnuwardhana University is a private institution with a green campus environment surrounded by Kerai Payung trees. This environment produces organic waste from trees and inorganic waste such as used paper from campus activities. This study aims to achieve zero-waste processing by using pyrolysis technology to process campus waste, ensuring minimal residue. The experimental method involves comparing waste processing outcomes between conventional combustion and pyrolysis, the data was analyzed by comparing the results of pyrolysis with conventional combustion. The results of biochar from the pyrolysis process of used paper, Kerai Payung leaves, and nagging Kerai Payung tree are 76 g, 250 …

Dynamic Analysis And Fatigue Life Evaluation Of Single Herringbone Planetary Gear System With Crack Fault, Dongping Sheng, Jie Yang, Chun Su

Journal of Mechanical Engineering Science and Technology (JMEST)

The herringbone planetary gear transmission is widely used due to its exquisite compact structure, excellent load-bearing capacity, and stable transmission characteristics. However, root crack is one of the most common failure modes of gears. A cracked herringbone planetary gear system is taken as research object. The sun gear with crack fault is studied from the aspect of modal and transient dynamic analysis, and the related results are compared with the healthy gear. Based on the transient dynamic analysis of the herringbone teeth with cracks, a fatigue life evaluation is conducted. Firstly, the results show that no significant difference between the …

Investigation Of The Influence Of Warhead Shape And Type Of Missile Weapon Material Counter-Training Tank Weapons Simulation Approach, Transisma Budiarta, Haris Puspito Buwono, Radhi Nurvian Amrullah

Journal of Mechanical Engineering Science and Technology (JMEST)

This study analyzes the effect of warhead shape and material variations on pressure, temperature, and lift on training missiles using CAD-based simulation methods. The variations of warhead shapes tested include flat, flat radius, and tapered, while the materials used are rubber, ABS, and PE. The simulation results show that the tapered warhead shape with PE material produces the lowest pressure (50.3 MPa) due to more efficient pressure release and low friction properties. Conversely, the Flat shape produces the highest pressure (69.1 MPa) on all materials due to flow stagnation. In terms of temperature, the Flat Radius warhead with PE and …

Investigation Of Drag Force And Downforce On Two Racing Motorcycles In Slipstream Conditions, Muhamad Hanifudin, Gaguk Jatisukamto, Mahros Darsin, Muh. Nurkoyim Kustanto, Azmi Saleh, Suprihadi Prasetyono, Catur Suko Sarwono

Journal of Mechanical Engineering Science and Technology (JMEST)

The performance of modern racing motorcycles is greatly influenced by their aerodynamics. Slipstreaming occurs during a race when a rider closely follows another, especially on a straight track. The effect can reduce aerodynamic drag and increase the overall speed of the rider behind. This study investigates the aerodynamic effects of slipstreaming on a racing motorcycle using computational fluid dynamics. This study also considers its effect on both drag force and downforce, which affects motorcycle stability. A 3D CAD model of a racing motorcycle and a rider in a crouching position was used as the object of research. CFD simulations were …

Characterization Of Curcumin As A Coating Material For Polymer-Free Stents Interms Of Morphology And Release, Ameliyana R.S.P.A. Yani, Muhammad Kusumawan Herliansyah

Journal of Mechanical Engineering Science and Technology (JMEST)

The use of bare metal stents over the long term often leads to the re-narrowing of blood vessels, prompting a shift to drug-eluting stents (DES). However, the use of polymers in DES has been known to trigger inflammation and thrombosis in the arteries. As an alternative, polymer-free drug-eluting stents (PF-DES) have emerged as a safer option. In this study, curcumin was selected as the primary coating material for PFDES using the electrophoretic deposition method. The effects of varying curcumin concentrations (125 µg/ml, 250 µg/ml, and 500 µg/ml) were examined to understand their impact on deposition morphology, coating weight, chemical bonding …

Influence Of Different Nanoparticles On Thermophysical Properties And Wear Resistance Of Corn Oil-Based Cutting Fluid In Mql-Cnc Milling Machining, M Nuril Anwar Habiby, Poppy Puspitasari, Aminnudin Aminnudin, Diki Dwi Pramono, Ahmad Atif Fikri, Mariyam Jameelah Ghazali

Journal of Mechanical Engineering Science and Technology (JMEST)

Vegetable oil-based cutting fluids have emerged as a promising innovation in machining operations, supporting the advancement of sustainable and eco-friendly manufacturing practices. This study delves into the development of a biolubricant derived from corn oil, enriched with 0.15% mass fractions of various nanoparticles, including calcium carbonate (CaCO3), copper oxide (CuO), and multi-walled carbon nanotubes (MWCNT). These nano-cutting fluids were applied through the Minimum Quantity Lubrication (MQL) method during CNC milling of AISI 1045 steel. The investigation focused on evaluating thermophysical properties, including density, thermal conductivity, and dynamic viscosity, as well as tool wear performance. The results demonstrated that CuO nanoparticles …

Impact Of Print Speed And Nozzle Temperature On Tensile Strength Of 3d Printed Abs For Permanent Magnet Turbine Systems, Wirawan Wirawan, Hilmi Iman Firmansyah, Satworo Adiwidodo, Mohammad Sukri Mustapa

Journal of Mechanical Engineering Science and Technology (JMEST)

Operational parameters must be integrated into turbine systems' main components, which are determined by turbine systems' functional requirements. The need for producing component designs more effectively raises the possibility of using additive manufacturing. The study focuses on the optimization of the mechanical properties of the principal components of magnetic turbines manufactured with 3D printers using Acrylonitrile Butadiene Styrene (ABS), by changing the temperature and speed of the nozzle. The approach consisted of modeling a standard test piece in CAD software and producing ABS-based test pieces using a 3D printer with print speeds of 50, 70, 90, and 110 mm/s and …

Performance Analysis Of Alkaline Fuel Cell With Variation Of Potassium Hydroxide Concentration In Electrolyte Solution, Mohammad Rifqy Alfariz, Nasrul Ilminnafik, Dwi Djumhariyanto, Intan Hardiatama, Muhammad Khadafi Ibnu, Raafi Aditya Nugraha, Domingos De Sousa Freitas

Journal of Mechanical Engineering Science and Technology (JMEST)

Alkaline Fuel Cell (AFC) is a green energy conversion tool that converts chemical energy into electrical energy through electrochemical reactions. This research aims to analyze the effect of potassium hydroxide (KOH) concentration variation in electrolyte solution on the AFC performance, using nickel and manganese catalysts. The research methods include experiments using various KOH concentrations to determine the optimal concentration to produce the best AFC performance. The voltage and current produced are measured, as well as the calculation of the electrical power and efficiency of the AFC. The results showed that KOH concentration has a significant influence on the performance of …

Toolpath Motion Strategy And Feed Rate In Cnc Milling On Energy Consumption Of Machining Process, Luqman Dwi Saputra, Eko Yudiyanto

Journal of Mechanical Engineering Science and Technology (JMEST)

The use of CNC milling machines to produce components, especially aluminum brackets used for automotive, is one of the advances in the industrial field. The use of CNC milling machines has the advantage of producing processes with speed accuracy, and better workpiece quality than conventional machines. This research investigates energy consumption in the CNC milling process by varying the toolpath motion strategies—Zigzag, Constant Overlap Spiral, Parallel Spiral, and Parallel Spiral Clean Corners—as well as feed rates of 700 mm/min, 800 mm/min, 900 mm/min, and 1000 mm/min. The goal is to find out the best parameters for using energy in the …

Boiling Heat Transfer Coefficient And Critical Heat Flux On Conical Cylindrical Copper Under Surface Modification, Muhammad Dimyati Nashrullah, Andi Sanata, Imam Solahuddin, Nasrul Ilminnafik, Indro Pranoto, Adhika Widyaparaga

Journal of Mechanical Engineering Science and Technology (JMEST)

This study examined how surface roughness and nanoceramic coating, influences the boiling heat transfer coefficient (BHTC) and critical heat flux (CHF) of a conical cylindrical copper test specimen. Three test specimens exhibiting surface roughness of 0.22 µm, 0.14 µm, and 0.04 µm were analyzed for comparison. Two additional test specimens were treated with nanoceramic coatings utilizing silicon carbide as the base material: one specimen received a single-layer coating and the second was applied with a double-layer coating. The behavior of the bubbles was closely observed with a high-speed camera to deepen the analysis. The experimental results showed that the test …

Development Of Adjustable Static Test Equipment For Below-Knee Prosthetic Feet: A Case Study, Firmansyah Hafizh Rizal Nurrokhim, Fauzan Raka Mawandi, Puspa Dinda Safitri, Imam Mahmudah, Dwiky Mirnanda, Ndaru Adyono, Wahyu Dwi Lestari

Journal of Mechanical Engineering Science and Technology (JMEST)

The high prevalence of physical disabilities in Indonesia, particularly among the productive-age population, highlights the urgent need for advancements in prosthetic technology. While local fabricators have begun producing prosthetic feet, the lack of standardized testing procedures compromises safety and performance. This study addresses that gap by developing an adjustable static testing device tailored for below-knee prosthetic feet, focusing on keel and heel tests to evaluate mechanical performance. The device includes a jig-fixture platform adjustable to 8° and 15° for heel and keel tests, respectively. It applies a 1230 N load based on AOPA standards and integrates load and displacement sensors …

Performance Of Rice Grain Conveyor Vacuum Blower With Variations In The Number And Shape Of Impeller Angles, Dedi Suwandi, Agus Sifa, Tito Endramawan, Kasni Sumeru, Ismail Wellid

Journal of Mechanical Engineering Science and Technology (JMEST)

Separating rice and bran, moving rice to storage, and other processes related to moving grain or rice. In the modern rice milling industry, the process of transferring grain material already uses a pneumatic conveying system; a vacuum blower system for transferring grain is needed when milling grain to become rice. The research method used to obtain the shape of a vacuum blower with strong inlet suction power and outlet thrust is carried out by Computational Fluid Dynamics simulation and testing several types and variations in the number of blades. Simulation of forward curved blade type impellers, backward curved blade, and …

Characterization Of Bamboo Petung Fiber Reinforced Composites With Environmentally Friendly Enzymes, Rudianto Raharjo, Teguh Dwi Widodo, Redi Bintarto, Fikrul Akbar Alamsyah

Journal of Mechanical Engineering Science and Technology (JMEST)

Natural fiber composites are a good choice for many businesses uses because of their better mechanical properties and are friendly environment. Researchers are currently looking into bamboo petung fiber (BPF) and epoxy composites as alternative to synthetic fibers and products made from petroleum. This study's goal is to improve the overall performance of these composites while reducing the need for non-organic materials. This study used the various concentration of bromelain enzyme in BPF to changes the mechanical and physical properties of epoxy composites made from BPF. Composites were characterized the mechanical properties including tensile strength using tensile tester, impact strength …

Multiple Input–Single Output (Miso) Framework For Low Velocity Impact Response Of Hybrid Gongronema Latifolium/S-Glass Fibre Epoxy Composites, Christian Emeka Okafor, Peter Chukwuemeka Ugwu, Godspower Onyekachukwu Ekwueme, Nürettin Akçakale, Emmanuel Chukwudi Nwanna

Journal of Mechanical Engineering Science and Technology (JMEST)

Sustainable composites are vital for impact-critical aerospace, automotive, and defense applications. This study used Multiple Input–Single Output (MISO) experimental approach to assess how hybrid ratio, mass fraction, and fiber orientation influence the low-velocity impact behavior of Gongronema/S-glass epoxy composites. Gongronema fibers and S-glass were combined with ER-F292 epoxy and molded into ASTMstandard samples. Charpy impact tests measured energy absorption. A 60-run design evaluated input variable combinations, and Multiple Linear Regression identified significant predictors using p-values and confidence intervals. Results showed that the mean values for hybridization ratio, mass fraction, fiber orientation, and low velocity impact were (2.50), (27.79%), (67.90°), and …

Tear Resistance Evaluation Of Room Temperature Vulcanizing Silicone Rubber: A Comparative Study, F R. Mawandi, P D. Safitri, D Mirnanda, F H. R. Nurrokhim, Ndaru Adyono, W D. Lestari

Journal of Mechanical Engineering Science and Technology (JMEST)

Room Temperature Vulcanizing (RTV) silicone cures at room conditions, providing tear resistance and flexibility to a wide range of industries. Yet, its mechanical performance improvement continues to be difficult when it is filled and catalyzed. In this work, the tear resistance of three RTV materials—RTV 48, RTV 683, and RTV M4503—is investigated with different talc (2–4 wt.%) and catalyst (40–60 wt.%) formulations. Tear resistance testing per ASTM D624 yielded average and standard deviation values for material consistency determinations. Comparative analysis is also given in the research to ascertain the effect of over-cross-linking on elasticity and structural morphology. RTV 48 experienced …

Effect Of Various Canopy Shapes On The Drag Coefficient Of Pickup Trucks, Khairil Anwar, Muhammad Syaiful Fadly, Muhammad Wahyu Hermanto

Journal of Mechanical Engineering Science and Technology (JMEST)

The aerodynamic performance of light commercial vehicles, such as the Suzuki Carry, plays a crucial role in their fuel economy and road stability. One typical add-on, a canopy, often changes that airflow and, as a result, alters the drag acting on the vehicle. In this study, three different canopy shapes, flat, curved, and triangular, were examined to understand how each one affects the drag coefficient (Cd). To investigate this, both wind tunnel trials and CFD runs were conducted to track the airflow and measure any changes in drag with greater detail. For reference, the exact vehicle without a canopy was …

Analyzing The Performance Of A Solar-Assisted Grain Dryer, Daniel Parenden, Frederik H. Sumbung, Peter Sahupala

Journal of Mechanical Engineering Science and Technology (JMEST)

This study evaluates the drying performance and energy efficiency of a solar-powered rice cabinet dryer equipped with two distinct airflow mechanisms: free convection (chimney-assisted) and forced convection (fan-assisted). Field experiments were conducted under tropical conditions in Merauke, Indonesia, comparing drying efficiency, moisture reduction, and air mass flow across three rice grain loads: 1 kg, 3 kg, and 5 kg. The experimental design incorporated both thermal analysis and statistical evaluation (ANOVA and t-tests) to assess the effects of airflow method and grain weight on drying outcomes. Results indicate that the chimney system demonstrated more stable and efficient performance at lower grain …