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Articles 481 - 510 of 30008
Full-Text Articles in Engineering
Ngc - Torch Test Ablation Stand Improvements And Upgrades, Sarah Nelson
Ngc - Torch Test Ablation Stand Improvements And Upgrades, Sarah Nelson
Undergraduate Honors Capstone Projects
This capstone project is sponsored by Northrop Grumman (NGC). The goal of the project is to redesign an ablation torch testing system to improve usability, safety, and versatility. Northrop Grumman relies on their ablation torch testing system to conduct quantitative evaluations of materials and high stress and high temperature conditions. The system provides essential data that supports product development, safety validation, and compliance with performance standards. By improving usability, safety, and versatility, NGC will be able to streamline testing operations, increase accuracy of results, and reduce operator risk. The system must allow testing using both a bent and straight torch …
Decomposition And Spectral Characterization Of Unsteady Loads In Pulse-Jet Propulsion Testing, Cesar Benitez
Decomposition And Spectral Characterization Of Unsteady Loads In Pulse-Jet Propulsion Testing, Cesar Benitez
Theses and Dissertations
Pulsed jet propulsion systems produce inherently unsteady forces whose time-resolved characterization is essential for performance assessment, yet the measured load signal conflates aerodynamic forcing with the dynamic response of the measurement balance itself. This thesis develops a load centered framework for the dynamic characterization of a pulsed jet system, treating the measured load fluctuation as the primary physical observable rather than attempting full true-thrust reconstruction. A single-degree-of-freedom balance model identified through ringdown testing provides the structural reference scale, yielding a natural frequency of 8.5 Hz and damping ratio of 18%. Power spectral density, phase-averaging, and synchronous–residual decomposition is applied uniformly …
Examining The Effects Of Lateral Loading On Railroad Tapered Roller Bearings, Abel David Sanchez Trinidad
Examining The Effects Of Lateral Loading On Railroad Tapered Roller Bearings, Abel David Sanchez Trinidad
Theses and Dissertations
The loading conditions experienced by freight railcar bearings vary as a function of vehicle operating conditions. Under static conditions, bearings are primarily subjected to radial loads transmitted through the wheelset. During operation, however, track irregularities, braking events, railcar load imbalances, and curving introduce complex impact, longitudinal, and lateral forces in addition to the normal radial loading. These lateral forces increase friction within the bearing raceways, which could accelerate wear and potentially lead to premature spall initiation and propagation. While prior research at the University Transportation Center for Railway Safety (UTCRS) has demonstrated that vibration signatures can be used to detect …
Manufacturing Systems: Characteristics And Dynamics, Alan J. Fitzmorris
Manufacturing Systems: Characteristics And Dynamics, Alan J. Fitzmorris
Graduate Theses and Dissertations (2019 - present)
This research answers three basic questions. First, what are the behaviors (dynamics) of a manufacturing system in the context of system performance? Are these dynamics best described as linear deterministic, periodic, nonlinear deterministic, or stochastic? Second, what are the complexity (chaotic) characteristics of a manufacturing system, namely the maximal Lyapunov exponent, correlation dimension, and Kolmogorov-Sinai entropy? Third, is there a relationship between complexity characteristics and manufacturing system performance? This research involves four high level steps: data analysis, system dynamics analysis, system complexity analysis, and correlation analysis. The data analyzed consists of concrete plant and shipbuilding shop time series performance data. …
Design And Development Of A Passive Dust Protection System For Lunar Docking Operations, Simon Thengvall
Design And Development Of A Passive Dust Protection System For Lunar Docking Operations, Simon Thengvall
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Lunar docking systems face a unique set of environmental conditions that can create significant challenges for mechanical design. Among these, the abrasive nature of lunar regolith can impair the kinematic function of traditional terrestrial mechanisms as well as contaminate critical spacecraft components such as environmental seals, causing them to fail. For crew-rated docking systems, failure of these systems not only threatens mission success, but also crew safety, so dust protection is crucial for docking components. To address the concerns of regolith intrusion, the Simple External Attachment for Lunar Openings (SEALO) is developed as a key architecture for mechanism evaluation when …
An Experimental Study On Turbine-Based Energy Harvesters For Thermal Underwater Gliders, Stephen Edward Coster
An Experimental Study On Turbine-Based Energy Harvesters For Thermal Underwater Gliders, Stephen Edward Coster
Theses and Dissertations
Buoyancy-driven underwater gliders have been optimized for long-duration missions primarily for continual monitoring of the ocean’s water column. However, longer missions and higher-powered sensors have increased the energy requirements of gliders. While current solutions aim to increase battery capacity, the development of energy-harvesting systems (EHMs) could greatly improve mission capabilities in both ability and duration. This thesis discusses the experimental testing of an underwater glider with an EHM as detailed in the theoretical study, “Development of a Turbine-Based Ocean Thermal Energy Harvesting Mechanism Applied to the Underwater Glider” by Hongbo Hou, PhD. The rear-mounted turbine captures energy using the kinetic …
Numerical Investigation On Lightning Survivability And Residual Strength Of Scarf-Patched And Z-Pinned Cfrp Composites, Logan Hales
All Graduate Theses and Dissertations, Fall 2023 to Present
Carbon fiber reinforced polymer (CFRP) composites are critical in aerospace applications yet remain vulnerable to lightning strikes due to orthotropic electrical conductivity and poor thermal resistance. Over the past decades, lightning-strike damage in pristine CFRP has been extensively investigated. However, the response of damaged and subsequently repaired laminates remains poorly understood, raising concerns about the structural integrity of repaired aircraft. This study aims to develop a sequentially coupled thermo-structural modeling framework to quantify how two common composite repair strategies (scarf patching and z-pinning), along with patch size, pin material, and configuration, influence lightning-induced damage and the residual flexural strength of …
Aerodynamic Parameter Estimation For A Scaled F-16: A Simulation-Based Sensitivity Analysis, Kathle C. Tischner
Aerodynamic Parameter Estimation For A Scaled F-16: A Simulation-Based Sensitivity Analysis, Kathle C. Tischner
All Graduate Theses and Dissertations, Fall 2023 to Present
The physical motion of an aircraft is determined by the resulting forces and moments acting on the aircraft. These forces and moments can be defined as a mathematical equation where the control deflections, rotation rates, and orientation of the aircraft are multiplied by individual constants and summed together to define the entire force or moment. This method results in a highly accurate model that defines the motion of the aircraft at low angles of attack and sideslip. Initial calculations of the aerodynamic model are created based on analytical estimations based on the physical properties of the aircraft. Additional refinement of …
Development Of A Novel Method For Simultaneously Testing Multiple Specimens To Evaluate Tension-Tension Fatigue Life, Mehedi Hasan Mahfuz
Development Of A Novel Method For Simultaneously Testing Multiple Specimens To Evaluate Tension-Tension Fatigue Life, Mehedi Hasan Mahfuz
All Graduate Theses and Dissertations, Fall 2023 to Present
The aim of this study is to develop a novel method for rapidly evaluating the tension–tension fatigue life of metals. Fatigue failure, which occurs when materials gradually weaken and fracture under repeated loading, is a critical concern in designing safe and reliable structures such as airplanes, cars, and bridges. Traditional fatigue testing methods are slow, costly, and typically limited to one specimen at a time. To address this, a high-throughput testing method was developed that allows multiple small-scale specimens to be tested simultaneously while following international testing standards. Using stainless steel sub-sized specimens scaled at 1:5 relative to the ASTM …
Two Applications Of Lifting-Line Theory For The Design Of Efficient Aircraft, Amanda K. Olsen
Two Applications Of Lifting-Line Theory For The Design Of Efficient Aircraft, Amanda K. Olsen
All Graduate Theses and Dissertations, Fall 2023 to Present
Numerical lifting-line is a tool that can be used to evaluate the forces and moments of an aircraft wing. This method has limitations but it is beneficial in obtaining a large set of results with relatively little computational power. This research seeks to analyze two different flight scenarios through the use of two numerical lifting-line tools developed at the Utah State University AeroLab. The first scenario involves an aircraft in ground effect flight. When an aircraft flies close to the ground, a phenomenon called ground effect occurs where the lift is increased and the induced drag is decreased. Therefore, flying …
Developing And Improving Digital Image Correlation (Dic) Techniques For Challenging Environments, Prasenjit Dewanjee
Developing And Improving Digital Image Correlation (Dic) Techniques For Challenging Environments, Prasenjit Dewanjee
All Graduate Theses and Dissertations, Fall 2023 to Present
Understanding how materials and parts deform during testing is crucial for creating safer and more reliable engineering systems. Engineers need to measure not only how much a part deforms, but also where deformation concentrates before any damage or failure happens. Digital image correlation (DIC) is a camera-based, non-contact measurement method that tracks surface motion and deformation across a whole area. It is particularly useful when traditional contact-based measurement techniques cannot withstand harsh conditions or capture enough detail. This dissertation develops optical methods to improve DIC in three challenging measurement situations. First, a shortwave ultraviolet lighting technique is developed to reduce …
Cylindrical Versus Spherical Self-Similar Capillary Cavity Collapse, Karl Cardin, Christophe Josserand, Raul Bayoan Cal
Cylindrical Versus Spherical Self-Similar Capillary Cavity Collapse, Karl Cardin, Christophe Josserand, Raul Bayoan Cal
Mechanical and Materials Engineering Faculty Publications and Presentations
Drop tower experiments have been performed to study the capillary collapse of large high-aspect-ratio cavities. Cavities are formed by momentarily impinging the free surface of a liquid bath with a jet of air in the microgravity environment of a drop tower. The collapse may give rise to a jet and three distinct jetting regimes are identified. Simulations are performed to further investigate the phenomena. The abrupt emergence of a thin high velocity jet is observed experimentally and numerically at a specific initial cavity aspect ratio. Different power laws are identified in different regions of the cavity during the collapse providing …
Optimization Of A Point Absorber Wave Energy Converter (Wec), Rutwa Dilipkumar Nagar
Optimization Of A Point Absorber Wave Energy Converter (Wec), Rutwa Dilipkumar Nagar
Electronic Theses and Dissertations
This study examines the performance and optimization of a point absorber wave energy converter with a partially submerged spherical float. A comprehensive open-source computational framework integrates frequency-domain hydrodynamic analysis with time-domain simulation using Capytaine, BEMIO, and WEC-Sim. Hydrodynamic coefficients such as added mass, radiation damping, and excitation forces are calculated and integrated into the governing equation of motion using the Cummins formulation. A parametric analysis varies the float diameter and geometric configurations across several cases. Hydrodynamic coefficients and response amplitude operators are assessed to analyze system behavior and resonance characteristics. Results indicate consistent trends in normalized added mass, with radiation …
The Pid-Based Three Quadcopter Uavs Formation Control Under External Disturbance, Vo Van An, Trinh Luong Mien
The Pid-Based Three Quadcopter Uavs Formation Control Under External Disturbance, Vo Van An, Trinh Luong Mien
Makara Journal of Technology
This paper presents the design and evaluation of a formation control strategy for three quadcopter UAVs, based on a PID controller in a leader–follower structure, under the influence of external disturbances. Each UAV employs a six-degree of-freedom dynamic model and utilises a cascade PID control architecture, in which the inner control loop stabilises the attitude. In contrast, the outer control loop regulates position and maintains the formation. The PID parameters are tuned using the Ziegler–Nichols method to ensure simple implementation and low computational cost. The performance of the control system is evaluated through simulations in the MATLAB environment for two …
Evaluation Of Quantification Methods Applied To Overlapping Ftir Features, Benjamin P. Diehl
Evaluation Of Quantification Methods Applied To Overlapping Ftir Features, Benjamin P. Diehl
Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)
Quantifying overlapping FTIR spectral features is critical for electrochemical analysis but often requires complex deconvolution. This work systematically evaluates several area ratio and proxy-based quantification methods using a controlled synthetic spectral model with varying signal-to-noise ratio, peak spacing, width, background, and data resolution. Constrained peak fitting and fixed-window integration consistently exhibit near-perfect monotonicity (Spearman ≈ 1.000) and linearity (Pearson ≈ 0.999–1.000) across all conditions. In contrast, derivative and moment-based metrics show sensitivity to peak overlap, width, and background. These results demonstrate that physically grounded area-based methods provide the most robust and reliable quantification of overlapping FTIR features.
External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos
External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos
Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–
Turbulence in wall-bounded flows governs momentum transport, drag, and energy efficiency in a wide range of engineering systems, yet its response to external forcing remains incompletely understood across transitional and high Reynolds number regimes. This dissertation investigates an active flow control strategy based on spanwise external forcing and demonstrates how it modifies the dynamics of transitional and turbulent channel flows with the objective of identifying the mechanisms through which forcing alters transition, flow physics, and turbulent drag reduction.
Firstly, direct numerical simulations are performed to examine the subcritical transition under external forcing. The onset and sustenance of turbulence are shown …
Vacuum Modification Of The Surface Properties Of T15k6 Hard Alloy By Plasma–Chemical Synthesis Of Tin-Cu Coatings, Aleksandr Semenov, Dmitriy Tsyrenov, Nikolay Ulakhanov, Irina Semenova, Undrakh Mishigdorzhiyn, Wen Ma, Simon C. Tung, George E. Totten
Vacuum Modification Of The Surface Properties Of T15k6 Hard Alloy By Plasma–Chemical Synthesis Of Tin-Cu Coatings, Aleksandr Semenov, Dmitriy Tsyrenov, Nikolay Ulakhanov, Irina Semenova, Undrakh Mishigdorzhiyn, Wen Ma, Simon C. Tung, George E. Totten
Mechanical and Materials Engineering Faculty Publications and Presentations
The design and main parameters of a plasma–chemical reactor containing two compartments are presented. One compartment houses a vacuum-arc evaporator, while the other houses a planar magnetron. The compartments are separated by a diaphragm with a dosing slot for injecting copper vapor into the TiN synthesis compartment. The conditions for the synthesis of superhard TiN-Cu composite coatings are experimentally determined. Based on established process parameters for TiN synthesis in a nitrogen-containing plasma by Ti evaporation using a vacuum-arc discharge, it is proposed to apply TiN-Cu coatings by injecting Cu vapor into the TiN synthesis area and sputtering Cu using a …
Lockheed Martin & U.S. Navy Air Pallet For Materials Handling, Samantha Ryan, Ryan Zerneke, Joshua Bible, Justin Conner, Brycen Haner, Nevan Juteram, Alexander Lacy, Gavin Lanka, Henry Lewis
Lockheed Martin & U.S. Navy Air Pallet For Materials Handling, Samantha Ryan, Ryan Zerneke, Joshua Bible, Justin Conner, Brycen Haner, Nevan Juteram, Alexander Lacy, Gavin Lanka, Henry Lewis
Mechanical and Civil Engineering Student Publications
The purpose of this project is to design, manufacture, and deliver an Air Pallet capable of lifting heavy loads and positively engaging with the Drive Tractor for movement. This project was developed to address current maintenance hazards and difficulty, structural integrity concerns, and increase system reliability for our customers Lockheed Martin and the United States Navy.
3d Filament Recycler, Connor Easley, Stephan Jean-Baptiste, Armando Loynaz, Brody Paulk, Meagan Prouty, Tai Roberts, Jack Salcedo, Vanessa Tohorton, Alex Tremblay, Ruhaan Zaveri
3d Filament Recycler, Connor Easley, Stephan Jean-Baptiste, Armando Loynaz, Brody Paulk, Meagan Prouty, Tai Roberts, Jack Salcedo, Vanessa Tohorton, Alex Tremblay, Ruhaan Zaveri
Mechanical and Civil Engineering Student Publications
The purpose of the project is to design and manufacture an integrated system for the L3HSDC that can recycle 3D filament waste by shredding, heating, extruding, and spooling it.
The Matear System, Kylie Strong, Adel Siraeva, Julianna Bartus, Lilly Davies, Cameron Deen, Rayna Doty, Amiana Mata, Jack Minners, Matthew Skwiot
The Matear System, Kylie Strong, Adel Siraeva, Julianna Bartus, Lilly Davies, Cameron Deen, Rayna Doty, Amiana Mata, Jack Minners, Matthew Skwiot
Mechanical and Civil Engineering Student Publications
The MATEAR attachment collects regolith simulant and uses compression and heat to form brick-like building blocks for sustainable infrastructure. It mounts to the Clearpath Robotics Husky A200 rover provided by the team’s faculty advisor.
Lockheed Martin & U.S. Navy Drive Tractor, Nicolas Czincila, Andrew Pestone, Santiago Florez-Tascon, Kalvin Long, Nick Norman, Joseph Phan, Ashlynn Redding, Brandon Ribeiro, Noah Rodriguez, Diana Viherek, Mckenzie Winder
Lockheed Martin & U.S. Navy Drive Tractor, Nicolas Czincila, Andrew Pestone, Santiago Florez-Tascon, Kalvin Long, Nick Norman, Joseph Phan, Ashlynn Redding, Brandon Ribeiro, Noah Rodriguez, Diana Viherek, Mckenzie Winder
Mechanical and Civil Engineering Student Publications
The purpose of this project is to design and manufacture a manually operated, pneumatic-assisted Drive Tractor system for transporting heavy loads with the Air Pallet. This project was developed to improve maneuverability, reduce operator effort, and increase system reliability within industrial environments for our customers Lockheed Martin and the U.S Navy.
Sparcc – Solar Panel Augmentation Via Regulated Cooling And Cleaning, Zachary Rodgers, Connor Fromme, Mohammed Al Jahwari, Jack Connor, Nicolas Hubley, Adrian Kingdollar, Iain Leroy, Maria Jesus Munoz, Ashton Stringer
Sparcc – Solar Panel Augmentation Via Regulated Cooling And Cleaning, Zachary Rodgers, Connor Fromme, Mohammed Al Jahwari, Jack Connor, Nicolas Hubley, Adrian Kingdollar, Iain Leroy, Maria Jesus Munoz, Ashton Stringer
Mechanical and Civil Engineering Student Publications
Problem Statement: Solar energy is the fastest-growing source of energy in the world. Solar cells lose efficiency by 0.35-0.7% per degree Celsius and up to 98% from debris build up. The primary objective of SPARCC was to improve cell efficiency through cooling and cleaning. A brush system with water spray was implemented to clean the panels, and a passive cooling system that utilizes a solar chimney, heat sinks, and phase change material to clean and cool.
Automatic Determination Of Mechanical Properties From Molecular Dynamic Stress-Strain Curves Using Regression Fringe Response, Josh Kemppainen, Tristan Muzzy, Travis Wavrunek, Gregory Odegard
Automatic Determination Of Mechanical Properties From Molecular Dynamic Stress-Strain Curves Using Regression Fringe Response, Josh Kemppainen, Tristan Muzzy, Travis Wavrunek, Gregory Odegard
Michigan Tech Publications
Molecular dynamics (MD) simulations have become a powerful tool for studying polymers, designing new materials, and composites. Mechanical behavior in MD simulations are typically evaluated through stress-strain curves. However, MD-generated stress-strain curves are often obscured by thermal noise from atomic vibrations. This noise complicates the reliable derivation of mechanical properties and hinders objective and reproducible analysis. The noise in the stress-strain curves has been removed by using a Butterworth low-pass filter, enabling clearer interpretation of stress-strain data. Building on this, a novel analysis framework the Regression Fringe Response (RFR) is introduced to systematically determine the Young's modulus, yield strength, and …
Transitional And Turbulent Dynamics In Viscoelastic Wall-Bounded Flows, Alexia Martinez Ibarra
Transitional And Turbulent Dynamics In Viscoelastic Wall-Bounded Flows, Alexia Martinez Ibarra
Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–
The addition of small amounts of long-chain polymers to a turbulent flow has been reported to modify the flow phenomena when compared to Newtonian flows, resulting in a significant skin-friction reduction. Although polymer-induced drag reduction has been extensively studied through both experimental and numerical studies, a unified and predictive understanding of the phenomenon is still lacking. This dissertation focuses on better understanding of this phenomenon, particularly on the transitional regime, which remains largely unexplored but is of utmost importance for both practical and fundamental purposes.
Firstly, direct numerical simulations are performed to study the effect of polymers on the laminar-turbulent …
Cast In Steel: Horseman's Axe, Sam A. Morris
Cast In Steel: Horseman's Axe, Sam A. Morris
Create@State
Cast in Steel is a competition between universities across North America started by the Steel Founders Society of America. The competition is centered around giving students the opportunity to learn about casting and the steel industry in general. A prompt of a weapon or tool with some level of historical significance is given to all the teams. The prompt for the 2026 Arkansas State University team, was a Horseman’s Axe. The team designed their rendition of a horseman’s axe, worked with Southern Cast Products as their local industry parter, and fabricated a finished axe to represent Arkansas State University as …
Analysis For Predicting Surface Temperature And Combustion Of Heavy-Duty, Pre-Chamber-Enabled, Hydrogen Engines, Tony Spezia
Analysis For Predicting Surface Temperature And Combustion Of Heavy-Duty, Pre-Chamber-Enabled, Hydrogen Engines, Tony Spezia
Master's Theses (2009 -)
Hydrogen as an alternative fuel shows great promise to help reduce greenhouse gas emissions from heavy duty engines. However, the challenge for hydrogen engines is that hydrogen has very different combustion properties compared to conventional hydrocarbon fuels. Hydrogen has very high flame speeds, very low ignition energy, and very wide flammability limit. These properties result in hydrogen engines being prone to abnormal combustion. Abnormal combustion makes hydrogen engines difficult to control or can cause catastrophic damage to the engine, so it is important to avoid conditions where abnormal combustion occurs. Hot spots along the combustion chamber walls are often the …
Techno-Economic Analysis Of Hybrid Systems As A Solution For Electricity Supply During The Dry Season At The Bakaru Run-Of-River Hydropower Plant, Zamharir Aditya Febri, Mohammad Akita Indianto, Sheila Tobing
Techno-Economic Analysis Of Hybrid Systems As A Solution For Electricity Supply During The Dry Season At The Bakaru Run-Of-River Hydropower Plant, Zamharir Aditya Febri, Mohammad Akita Indianto, Sheila Tobing
Journal of Materials Exploration and Findings
Within the South Sulawesi power system (Sulbagsel), the Bakaru Hydro Power Plant serves as a key facility expected to provide consistent and reliable electricity supply. However, since the Bakaru plant operates under a Run of River scheme, its energy output is highly dependent on river discharge rates. In 2024, a significant decrease in water flow was recorded between August and October, which led to a drastic reduction in power generation. To address this challenge, a hybrid energy system is proposed to ensure continuous load coverage, particularly during the dry season. The optimal configuration of this hybrid system was modeled and …
Techno-Enviro-Economic Analysis Of Precipitated Calcium Carbonate Production From Carbon Dioxide In Cement Industry Flue Gas And Calcium Hydroxide, Natalia Debora Panggabean, Widodo Wahyu Purwanto
Techno-Enviro-Economic Analysis Of Precipitated Calcium Carbonate Production From Carbon Dioxide In Cement Industry Flue Gas And Calcium Hydroxide, Natalia Debora Panggabean, Widodo Wahyu Purwanto
Journal of Materials Exploration and Findings
CCUS is a technological solution to reduce emissions from the cement industry, which is the second largest CO2-intensive industry. This study aims to analyze technical, economic, and environmental performance of Precipitated Calcium Carbonate (PCC) synthesis in cement industry flue gas. The process simulation includes the CO2 capture system from cement plant, CO2 captured used as feedstock for PCC synthesis process through its reaction with calcium hydroxide. The simulation was carried out using ASPEN Plus software. Technical analysis was performed to determine the CO2 capture efficiency and PCC synthesis efficiency. Economic analysis was conducted to calculate CO2 capture cost and production …
Feasibility Analysis Of Thermal Oxidizer To Determine Remaining Life Using Fitness- For-Service Level 3 Method, Yudhi Yudistirawan, Donanta Dhaneswara, Wahyuaji Narottama Putra, Gama Widyaputra, Dewi Kurnia Suci, Agung Putra Mahardhika
Feasibility Analysis Of Thermal Oxidizer To Determine Remaining Life Using Fitness- For-Service Level 3 Method, Yudhi Yudistirawan, Donanta Dhaneswara, Wahyuaji Narottama Putra, Gama Widyaputra, Dewi Kurnia Suci, Agung Putra Mahardhika
Journal of Materials Exploration and Findings
An aged thermal oxidizer (TOX) in the oil and gas industry necessitates a comprehensive evaluation to ensure its continued safe operation. This study presents a Remaining Life Assessment (RLA) and a Fitness for Service (FFS) evaluation for the four main components of the TOX, in accordance with API 510, API 579/ASME FFS-1, and ASME BPVC Section VIII Div-1 standards. The investigation includes the determination of maximum stress and maximum temperature required to assess the operational viability of the reactor. The four components are radiant, convection, transition, and stack sections—were modeled using the finite element method (FEM). Following the geometric modeling, …
Risk Identification Of Green Hydrogen Supply Chain In Ammonia Industry In Indonesia Using Delphi And Topsis Methods, Ananda Priatama, Sheila Tobing
Risk Identification Of Green Hydrogen Supply Chain In Ammonia Industry In Indonesia Using Delphi And Topsis Methods, Ananda Priatama, Sheila Tobing
Journal of Materials Exploration and Findings
The development of green hydrogen in Indonesia, while promising for supporting industrial decarbonization, remains in its early stages and faces various challenges across technical, economic, and regulatory domains. This study aims to identify and prioritize the risks linked to green hydrogen supply chain in Indonesia, particularly for applications in the ammonia industry. A set of 49 potential risk factors was initially compiled through literature review and prior studies. The Delphi method was employed with a panel of experts to validate these risks, ultimately refining the list to 27 critical risk factors. Subsequently, the Technique for Order Preference by Similarity to …