Mechanical Engineering Commons^™

Numerical Simulation Of Centrifugal Pump Performance Under Impeller Blade And Suction Diameter Variations, Gunawan Budi Santoso, Susanto -, Akhmad Nuriyanis, Anang Budhi Nugroho, Rizka Noor Miftakhul Ulum, Suyono -

Journal of Mechanical Engineering Science and Technology (JMEST)

The objective of this study is to model variations in pump geometry to obtain optimal performance under the effects of cavitation. The resulting geometric variation models were then simulated using ANSYS Fluent software. The first geometric variation model used a standard 5-blade impeller with suction pipe diameter variations of 2, 2 ½, 2 ¾, 3, 3 ¼, 3 ½, and 4 inches. The second geometric variation model for simulation used a standard 3-inch suction pipe with impeller blade variations of 3, 4, 5, 6, 7, 8, and 9. The simulation results indicated that the number of blades without changes in …

Characterization Of Various Corrosion-Resistant Rebars Embedded In Concrete After 20 Years Of Exposure, Samantha Mavrak

Electronic Theses and Dissertations

In aggressive marine environments, the deterioration of reinforced concrete structures is primarily caused by chloride-induced corrosion of embedded carbon steel reinforcement, resulting in concrete cracking, spalling, and costly maintenance or premature replacement. Corrosion-resistant reinforcement has been developed to mitigate these effects; however, long-term field performance data remain limited. This study evaluates the long-term corrosion performance of several corrosion-resistant rebars embedded in simulated deck slab concrete specimens following approximately 20 years of chloride exposure.

Concrete specimens containing 304SS, 316SS, and 2304 duplex SS, two types of clad reinforcement (316SS with carbon steel core), and an intermediate alloy with 12% Cr were …

Property Tables For Thermally Perfect Gases At Low Pressure, Travis J. Moore, Matthew R. Jones

Faculty Publications

Tables giving gas properties at low pressure enable the efficient analysis of processes in which the gas is approximated as thermally perfect but not calorically perfect. In addition to specific enthalpy and specific internal energy, thermally perfect gas tables include special functions that depend only on temperature—relative pressure and relative specific volume. These functions may be used to determine pressure, volume, and temperature of thermally perfect gases undergoing hypothetical isentropic processes. However, the definitions of these functions included in widely used thermodynamics textbooks are vague, inconsistent, or incorrect. The intent of this work is to discuss common inaccuracies in the …

Enhancement Of A Copolyester’S Impact Resistance Via Inorganic Reinforcement, David Felipe Gonzalez

Electronic Theses and Dissertations

Thermoplastic copolyester elastomers (TPEEs) are widely used in engineering applications because of their flexibility, toughness, and chemical resistance. However, prolonged exposure to marine environments can reduce their mechanical performance through moisture-induced degradation. This research investigated the use of titanium dioxide (TiO2) nanoparticles and APTES-functionalized TiO2 nanoparticles to improve the mechanical, thermal, and environmental durability of Hytrel 5556. Nanocomposites containing 1 wt.% and 2 wt.% TiO2 were fabricated through melt blending and compression molding. Mechanical properties were evaluated through tensile, compression, flexural, and impact testing, while thermal behavior was characterized using differential scanning calorimetry (DSC). Nanoparticle dispersion was examined using scanning …

A Reduced-Order Framework For Stochastic Criticality Estimation In Granular Energetic Materials, Philip T. Melton

LSU Master's Theses

Granular energetic materials (EMs) exhibit stochastic shock initiation because pore collapse, frictional dissipation, and localized thermal activation depend on microstructural descriptors that vary between nominally identical samples. Fully resolved mesoscale and atomistic calculations can represent these mechanisms, but their computational cost limits direct ensemble evaluation of microstructure-conditioned criticality thresholds. This thesis introduces a reduced-order framework for stochastic criticality estimation in granular EMs by coupling five explicitly defined model components: first, a one-dimensional steady compaction-shock model that maps initial solid volume fraction and shock pressure to a bulk mass-specific dissipated-work budget; second, an SEM/synthetic-image segmentation workflow that extracts pore area, perimeter, …

Analysis Of The Fracture Toughness Of Ercual A2 Cladding On Api X70 Using The Instrumented Charpy Impact Test, Martín Aguirre-Pulido, Francisco Fernando Curiel-López, Jose Jaime Taha-Tijerina, Jorge Alejandro Verduzco-Martínez, Víctor Hugo López-Morelos, Heriberto Granados-Becerra, Ariosto Medina-Flores

Mechanical Engineering Faculty Publications

The degradation of steel used in the oil industry has become a serious problem due to the high costs associated with material loss from corrosion. Applying thin layers of corrosion-resistant material promises to be a viable alternative for extending the service life of pipelines. ERCuAl-A2 electrode claddings were applied to API X70 carbon steel using the MIG brazing process with direct current (DC) and pulsed current (P). The cladding was applied under three conditions: base material (BM) at room temperature, BM preheated to 120 °C, and Ni-buttered BM. Microhardness profiles and Charpy impact tests were performed on the MB and …

Evaluation Of Optimal Force For Intrusion Of A Periodontally Compromised Maxillary Anterior Dentition Treated With Fixed Orthodontics – A Finite Element Analysis, Tanzim Ahmed, Amrita Puri, Aatira Nair, Anshul Singla, Mathew Koshy Vaidyan, Shruti Sharma, Chhavi Singh

International Arab Journal of Dentistry

Introduction: Adult orthodontic treatment is increasingly sought due to aesthetic and functional concerns, often involving periodontally compromised patients with altered biomechanics. Reduced bone support shifts the center of resistance and necessitates lower, carefully controlled forces, while finite element modeling has become a key tool to analyze tissue response under such conditions.

Objectives: The study aimed to determine the optimal intrusive force for periodontally compromised maxillary anterior teeth using Finite Element Analysis (FEA).

Methods: A 3D finite element model of the maxillary anterior dentition was created and divided into healthy and compromised halves, the latter with one-third alveolar bone loss. A …

Effect Of Naoh Concentration On The Structural, Morphological, And Tensile Properties Of Pineapple Stem Fibers, Ahmad Norca Kurnia Zen, Heru Suryanto, Aminnudin Aminnudin, Fajar Nusantara, Joseph Selvi Binoj

Journal of Mechanical Engineering Science and Technology (JMEST)

Natural fiber reinforced composites are increasingly being developed due to their environmentally friendly nature, low production costs, and safety for human health. However, the presence of lignin and hemicellulose reduces adhesion properties between fiber and composite matrix. Alkalization treatment is an effective way to remove lignin and hemicellulose attached to cellulose. This study aims to determine the optimum concentration of NaOH used during alkalization process of pineapple stem fiber. The methods included the retting process of fibers from pineapple stems. The obtained fibers were soaked in variations of 2%, 4%, 6%, and 8% NaOH for 4 hours,  then dried and …

Pseudodifferential Absorbing Boundary Conditions For Waves, Lauren Taylor

Mechanical Engineering Theses

Absorbing boundary conditions (ABCs) are required to truncate the computational domain when performing Finite Element Analyses of exterior acoustic problems where physical domain is unbounded. ABC is applied on a fictitious boundary containing the scatterer and ideally allows outgoing waves to leave without non-physical reflections. Preventing artificial reflections is essential to benefit from the accuracy of the numerical method used. Otherwise, ABC acts as a reflective surface, and artificial reflections distort the solution in the entire domain which is not recoverable by any type of refinement. Pseudodifferential ABCs were used to describe the Dirichlet-to-Neumann map which maps known boundary values …

Performance Evaluation And Sustainable Benefits Of Using Metakaolin And Recycled Steel Fibers In Concrete, Lova Raju Surla, Ramprasad Naik Desavathu, Raja Murugadoss Jeyaraju

Journal of Sustainable Construction Materials and Technologies

The rapid accumulation of waste vehicle tires and the increasing demand for cement pose significant environmental challenges through land pollution and CO2 emissions. The combined use of recycled steel fibers (RSFs) recovered from waste tires and supplementary cementitious materials (SCMs) offers a sustainable solution to these issues. This study investigates concrete incorporating 20% fly ash (FA), varying metakaolin (MK) contents (4–16%), and RSF dosages of 0.5–1.5%. Mechanical properties (compressive, split tensile, and flexural strengths) and durability characteristics (sorptivity, water absorption, chloride permeability, and homogeneity) were evaluated at 7, 28, and 90 days. Results showed that the mixture containing 20% FA …

Climate-Responsive Design For Sustainable Construction: Passive Strategies In Domestic Architecture Supporting Sustainability, Nahed Chakouf

Journal of Sustainable Construction Materials and Technologies

This study explores climate-responsive design in domestic architecture, focusing on the application and effectiveness of passive strategies across various climatic regions, including the UK, hot-arid, tropical, and cold climates. A qualitative comparative case study method was used to explore different passive design strategies, integration of sustainability, procurement, the coordination of stakeholders, and compliance with regulations in residential architectural projects under varying climate conditions. Drawing from a combination of historical case studies and original architectural projects, the research evaluates how spatial configuration, material selection, solar orientation, shading, ventilation, and insulation are optimized to achieve thermal comfort and energy efficiency. In temperate …

Investigation Of Energy Efficiency Of An Autonomous Mobile Photovoltaic-Thermal (Pv/T) System With A Polycarbonate Absorber, Sanjar Kodir Ugli Shoguchkarov, Anvar Rakhmat Ugli Rakhmatov, Rushana Husen Kizi Abdullaeva, Orazbek Maratbay Ugli Temirbaev

Technical science and innovation

This study analyzes the enhancement of energy efficiency in photovoltaic-thermal (PV/T) systems, which enable the simultaneous generation of electrical and thermal energy from solar radiation. The research focus is an autonomous mobile unit based on multi-channel polycarbonate heat collectors with a hydraulic diameter of 8 mm, characterized by their lightweight nature and superior corrosion resistance compared to conventional metal absorbers. Experimental investigations were conducted at the solar testing field of the Physical-Technical Institute of the Academy of Sciences of Uzbekistan under extreme continental climatic conditions to determine the system's stable thermophysical indicators. The results demonstrated that active water cooling using …

Use Of New Improved Methods For Assessing The Engineering-Geological Characteristics Of Deposits By Depth (Using The Example Of The Akba Deposit)., Elboy Shavkatovich Qurbonov Salom, Abduboqib Djalilovich Karimov, Yokub Yarash Ugli Isomiddinov

Technical science and innovation

The article examines the fracturing and filtration properties of rocks in boreholes, rock outcrops, and underground mine workings at the Akba gold deposit. Based on the results of hydrogeological and engineering-geological studies, methods that fully meet modern requirements were used, the values of the RMR rating of rocks and the indicators of the qualitative content of RQD rocks, as well as the intervals of their changes, were studied, as a result of which it became possible to quickly and accurately assess the strength state of the rock mass of the deposit territory by depth and area.

Modeling Of Terpolymerization Kinetics And Determination Of Reactivity Ratios In The Tdma–Styrene–Maleic Anhydride System, Shohrux Boboxon Ugli Mavlonov, Sadriddin Fayzullayevich Fozilov

Technical science and innovation

In this study, the kinetics of terpolymerization, compositional evolution, and monomer reactivity ratios in the TDMA–styrene–maleic anhydride system were comprehensively investigated. Increasing the initiator concentration from 16.8×10⁻⁶ to 51.3×10⁻⁶ mol•L⁻¹ led to an increase in conversion from 6.4% to 15.2% and reaction rate from 4.075×10⁻⁶ to 8.965×10⁻⁶ mol•L⁻¹•s⁻¹. At low conversion (Xw≈0.02–0.09), the terpolymer composition remained close to the initial feed, although deviations due to differences in monomer reactivity were observed. With increasing conversion, some systems exhibited stable composition (±0.02), while others showed compositional drift (increase of MA fraction from 0.50 to 0.70). The determined reactivity ratios (rTDMA/St≈0.99; rSt/TDMA≈1.62; rTDMA/MA≈2.02; …

Development Of An Optimal Composition Of A Composite Solvent For Asphalt–Resin–Paraffin Deposits, Gulmira Abduvaliyevna Tadjiyeva, Xasan Irgashevich Kadirov, Shaxnoza Abduvaliyevna Tadjiyeva, Fazliddin Zokir Ugli Murodullayev, Bekmurodjon Baxtiyorjon Ugli Raximjonov

Technical science and innovation

A solvent formulation composed of aromatic hydrocarbons of the C9 fraction and aliphatic alcohols in a 1:1 ratio, supplemented with 1–3 wt.% of a nonionic surfactant, has been developed. The proposed composition demonstrates more than a twofold increase in dissolving and washing efficiency toward paraffin-type asphaltene–resin deposits. Furthermore, the solvent system exhibits pronounced depressant–dispersant properties with respect to paraffin-containing organic deposits. Although numerous investigations have addressed the development of technologies for removing organic deposits in oilfield equipment—primarily focusing on specific aspects of eliminating or preventing asphaltene–resin–paraffin deposits (ARPD) in wells—limited attention has been given to the design of integrated approaches. …

Technology For Obtaining Aliphatic Amines Based On Liquid By-Products Of Polymerization Processes, Kamila Sabirbaevna Allanazarova, Ulugbek Komiljonovich Urinov

Technical science and innovation

Polymerization processes generate considerable amounts of liquid secondary by-products, which are often underutilized despite their significant chemical potential. Addressing the need for sustainable resource use, this study aims to develop a technological method for converting these by-products into valuable aliphatic amines. The experimental approach involved the pre-treatment of liquid polymerization by-products through fractional distillation to isolate C3–C10 fractions, followed by catalytic amination using Raney nickel under controlled temperature (160°C) and pressure (12 atm) conditions. Analytical methods including gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FTIR) were employed to characterize the reaction products. The results demonstrated the successful formation of …

Optimization Of Aluminum Coating Deposition Parameters To Enhance The Performance Of Automotive Headlamps, Gulirano Saidakhmedova, Giovanni Maizza

Technical science and innovation

The paper investigates the influence of the optical characteristics of functional coatings applied to automotive reflectors on vehicle active safety parameters, with a focus on the range and intensity of road illumination. The study examines the mathematical relationship between the maximum luminous intensity of a headlamp, the object detection distance, and the reflection coefficient  of an aluminium layer deposited via vacuum thermal evaporation. The main factors driving the degradation of surface reflectivity (including oxidation, thermal degradation of the base coat, and surface roughness) are analysed. It is demonstrated that a decrease in the reflection coefficient during operation directly impairs the …

Adaptive – Compositional Method For Coordinating Subsystems At Different Levels In Hierarchical Control Systems, Husan Zakirovich Igamberdiyev, Uktam Farxodovich Mamirov Mr, Inomjon Ilxom Ugli Abdukaxxarov Mr

Technical science and innovation

This paper examines the problem of synthesizing algorithms for the composition of subsystems at various levels within complex hierarchical control systems under conditions of uncertainty and resource constraints. It is demonstrated that classical composition algorithms, which rely on the intersection of admissible sets and the use of local optimality criteria, suffer from several significant drawbacks. These include a combinatorial increase in complexity, dependence on the expert selection of parameters, and limited applicability in dynamic environments. To overcome these shortcomings, an adaptive-compositional method is proposed. This method is based on the dynamic recalculation of coordination parameters, the integration of model predictive …

Calculation Of The Basic Parameters Of The Hybrid Power Plant (Hpu) On The Spark Car, Rustam Raximovich Tillahodjaev, Jamoliddin Pardaboy Ugli Turdiev

Technical science and innovation

This article presents one of the effective ways to improve fuel efficiency and reduce emissions of toxic substances, the use of internal combustion engines with the use of an electric drive in their designs. In recent years, two directions in the development of cars with electromechanical drives have been clearly identified, the first is the creation of a pure electric car, the second is the development of an electromechanical drive with a combined (hybrid) power plant. Due to the lack of efficient energy storage available for mass production, pure electric vehicles have relatively low mileage on a single charge. This …

Experimental Study Of An Automotive Cooling System With A Mechatronic Control System, Avaz Israilovich Yangibayev

Technical science and innovation

This article presents the results of experimental investigations of a passenger car engine cooling system equipped with a mechatronic control system. The experiments were conducted on an intelligent hardware-software laboratory test bench developed using original components of a Chevrolet Gentra vehicle. The study determined the thermodynamic response characteristics and energy performance of the system under varying ambient temperatures (-10 to +50 °C) and engine thermal loads. The experimental results demonstrated that the mechatronic system can maintain coolant temperature with minimal fluctuation amplitude, ensure smooth transient processes, and significantly reduce electrical energy consumption. Based on the obtained results, scientific and practical …

Magnetic Field-Induced Transformation In Polycrystalline Ni2mnal Heusler Type Magnetic Shape Memory Alloy, Choji J. Daches, Joseph W. Newkirk, Mario Buchely, Laura N. Bartlett

Materials Science and Engineering Faculty Research & Creative Works

The martensitic and magnetic transformations, as well as the mechanical properties, of Ni₂MnAl alloys in as-cast (AC) and heat-treated (HT) conditions were investigated. Magnetic-field-induced strain was evaluated via magnetostriction, with reversible strains of 0.14% and 0.2% achieved in the martensitic phase at 2 K for the AC and HT alloys, respectively. Transformation temperatures and Curie temperatures were determined under constant applied magnetic field, revealing that γ-phase inclusions in the AC microstructure suppress antiferromagnetic domain response, yielding a lower magnetization (∼8.4 emu g⁻¹) compared to the HT alloy (∼13.4 emu g⁻¹). Both alloys exhibited hysteretic behavior in the martensitic state and …

Prediction Of Satellite Temperature During An Orbit Of A Cubesat, Michael Reynolds

Honors Theses

This thesis develops a thermal-simulation strategy for predicting CubeSat component temperatures, applied to Jag-Sat-1, a CubeSat developed at the University of South Alabama and deployed from the International Space Station in 2022. The orbit was reconstructed from two-line element (TLE) data using simplified general perturbations (SGP4) propagation, and spacecraft attitude was recovered from onboard gyroscope measurements. Sunlight, penumbra, and umbra intervals were computed geometrically, and the external radiative environment — direct solar, Earth infrared, and albedo heat fluxes — was modeled using orientation-dependent view factors. These time-varying fluxes drove a transient finite-element thermal simulation of the full satellite geometry in …

Direct Ink Writing Of Functional Fiber/Granular Composites, Zhuoyuan Yang

Doctoral Dissertations and Master's Theses

Direct ink writing provides a versatile manufacturing route for fabricating functional fiber and granular composites with controlled architecture, tunable interfaces, and customized material distributions. Fiber reinforced composites offer high stiffness, strength, fatigue resistance, and functional anisotropy, while granular composites provide scalable access to particle based structures with high material efficiency and broad resource compatibility. However, the additive manufacturing of these composite systems remains challenging. For fiber based composites, precise control of fiber placement, matrix impregnation, interfacial bonding, and freestanding deposition is difficult to achieve during printing. For granular composites, stable particle flow, controllable packing, binder infiltration, and shape retention are …

Neural Network Technologies In The Automatical Control Systems Of Absorption Process For Pureficating Natural Gas, Abdishukurov Maqsudovich Shavkat Mr, Xuecheng Li Li Xuecheng Mr

Technical science and innovation

Analysis of methods and algorithms for synthesizing adaptive control systems for technological processes based on the neural network approach is carried out in this search. The stages of mathematical modeling of complex technological processes using neural network technology were considered. Additionally, an algorithm for solving the interpolation and extrapolation problem that arises in the training process a neural network to control system was proposed. At the final stage of this article, algorithms based on neural network technology are synthesized for the control system for the parameters of the technological process of natural gas purification by absorption

Analysis Of Inhibitor Supply Control Systems To Prevent Hydrate Formation In A Low-Temperature Gas Separation Unit And A Method For Solving The Problem, Shakhzod Nurmuhammadovich Amirov Mr, Erkin Xxx Uljayev

Technical science and innovation

The article examines and analyzs patents, published scientific works, and currently used scientific and practical methods and devices for regulating the parameters of the low-temperature separation process in production. However, the conducted analysis showed that one of the main causes of hydrate formation in the device is the lack of continuous comprehensive control over parameters such as the pressure of the inhibitors supplied to the injectors at each stage and the moisture content of the total gas, i.e., the moisture content of the total gas at the system inlet, the gas temperature at the device outlet, and the pressure and …

Study Of Onshore And Offshore Upwind And Downwind Wind Turbine Configurations: Performance Differences And Aerodynamic Characteristics, Ahmed Ismail

Mechanical Engineering Theses

The aerodynamic performance and loading behavior of large- scale wind turbines depend heavily on atmospheric inflow conditions and rotor orientation. While upwind turbines remain the most common design in the industry, recent progress in materials, aeroelastic modeling, and control systems has sparked renewed interest in downwind configurations. This study aims to assess how ABL characteristics and rotor orientation affect the aerodynamic performance of a utility- scale wind turbine. A CFD framework was built in ANSYS Fluent to model the NREL 5 MW Reference Wind Turbine. Transient simulations employed the SST k–ε turbulence model under various inflow conditions: uniform, onshore, and …

Multidisciplinary Inverse Robust Co-Design Of Materials, Products, And Manufacturing Processes, H M Dilshad Alam Digonta

Theses and Dissertations

Realizing the design for Integrated Computational Materials Engineering (ICME) requires the materials, product, and manufacturing-process disciplines to be designed together. Because these disciplines interact and influence one another's decisions, coordination is needed among their distributed decision-makers. Their interactions are captured through the processing-structure-property-performance (PSPP) linkages, which must be established from limited, costly data. Moreover, each discipline introduces its own sources of uncertainty, and these propagate through the process chain to influence final product performance. The effective realization of the product-material-manufacturing system, therefore, calls for a co-design approach that enables the concurrent coordination of the interacting disciplines while quantifying and managing …

Production Of Seismic-Resistant Steel From Scrap With Up To 0.6% Copper, Iman El-Mahallawi, Ahmed Ramadan Seada Dr.

Mechanical Engineering

Earthquake-resistant steel grades of characteristic value defined by the ratio (UTS/YS) greater than 1.25 are verified through controlling the proportion of alloying elements in steel. This work illustrates a novel idea to produce earthquake-resistant steel grade utilizing steel scrap. Different heats were produced containing varying levels of copper, manganese, and silicon, along with deep desulfurization. The heats were hot rolled to diameters of 10, and 16 mm, followed by Tempcore process. JMatPro software was used to predict the formed phases. The chemical composition was determined by optical emission spectrometry. The tensile properties were determined by tensile testing, and bend testing …

Harnessing Tio2-Based Nanofilaments: A Pathway To Enhanced Optoelectronic Performance In Dye-Sensitized And Perovskite Light Harvesters, Zahraa Ismail, Tarek A. Elmelegy, Hassan Nageh, Sameh Abdellatif

Mechanical Engineering

This study explores the integration of TiO2-based nanofilaments into dye-sensitized solar cells (DSSCs) and perovskite solar cells (PSCs) to enhance their optoelectronic performance. Despite the advancements in one-dimensional lepidocrocite TiO2 nanofilaments, there remains a significant gap in understanding their optical scattering mechanisms and dual applicability in both types of solar cells. We synthesized TiO2 nanofilaments and compared their performance to conventional P25 TiO2 in terms of morphology, electrical, and optical properties. The results indicate that the DSSC utilizing nanofilaments achieved a short-circuit current density of 8.2 mA/cm² and a power conversion efficiency (PCE) of 6.9%, compared to 7.1 mA/cm² and …

Jme 4110: Drill-Powered Beach Umbrella Anchor, Matthew Barton, Tanin Ramnath, Marquan Bailey, Zachary Van-Horn, Kaelin Mendoza

Washington University / UMSL Mechanical Engineering Design Project JME 4110

A common and potentially hazardous situation faced by beachgoers is when standard umbrella anchors fail to hold during wind gusts, causing the umbrella to potentially go airborne and injure nearby people. Existing anchors require manual operation, leading to inconsistent grip and no resistance to different wind directions. Our project is a motorized three anchor system that drives augers into the sand to ensure a consistent grip and security against the wind.