Thermodynamics Commons^™

Investigations Of Conjugate Heat Transfer And Fluid Flow In Partitioned Porous Cavity Using Darcy-Forchheimer Model: Finite Element-Based Computations, Nasir Yasin, Shafee Ahmad, Muhammad Umair, Zahir Shah, Narcisa Vrinceanu, Ghadah Alhawael

Mathematics & Statistics Faculty Publications

The conjugate heat transfer and fluid flow has vast applications in thermal engineering, particularly for cooling in thermal devices, and automobile engines. This study investigates conjugate heat transfer in 2D enclosures, featuring thin solid fins attached to a porous bottom wall. The porous medium is considered isotropic and homogeneous by the Darcy-Forchheimer model, with fluid phases in local thermal equilibrium. The boundary conditions at the porous fluid interface ensure continuity of the velocities, stresses, temperature, and heat flux. The phenomenon is mathematically modelled by obtaining a set of partial differential equations. The finite element method (FEM) is used to perform …

Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola

Graduate Theses, Dissertations, and Problem Reports (ETD)

There has been an ongoing trend toward cleaner fuels for more environmentally benign forms of energy generation. Recently, hydrogen has been identified as a clean fuel for energy generation. However, the most established, efficient, and widely utilized technique for producing hydrogen remains the steam methane reforming (SMR) in the presence of catalyst. Unlike other fossil fuels, utilizing methane from natural gas in an SMR process to produce hydrogen emits less, but yet a notable sum of carbon dioxide. Furthermore, the endothermic nature of SMR reactions imply that there is a high energy requirement to obtain a substantial amount of hydrogen …

Modeling And Simulation Of A Process For Upcycling Of Low-Density Polyethylene Plastic Waste To Ethylene, Xiaoyan Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethylene is one of the most widely produced petrochemicals, with an estimated global output of 180 million metric tons in 2022. Approximately 82 million metric tons of ethylene are used annually for plastic production, primarily for polyethylene (PE), as well as polypropylene (PP) and polyvinyl chloride (PVC). The CO₂ emissions associated with PE production were approximately 14 million metric tons in 2022. Globally, an estimated 70 million metric tons of PE are produced and consumed each year, with the majority (~79%) ending up in landfills or the environment.

This project proposes a novel process in which waste low-density polyethylene (LDPE) …

(R2090) Analysis Of Heat And Mass Transfer In Mhd Boundary Layer Flow Of Chemically Reacting Fluid, Dharati Sheth, Manisha Patel, Dilip Joshi

Applications and Applied Mathematics: An International Journal (AAM)

Analysis of the effects of heat and mass transfer on the chemically responding boundary layer flow of a Casson fluid across a porous stretched sheet in the existence of a crosswise magnetic field is the aim of the existing work. The partial differential equations that control the current flow problems can be converted into similarity equations by applying the right similarity technique. Our goal is to use the DTM-Pade approximation to analytically solve the derived similarity equations. The transformed similarity equations are a group of nonlinear ordinary differential equations for the present flow problem. The analytical approach of the differential …

Monitoring Of Laser Soldering Process In Hybrid Additive Manufacturing, Alexander P. Pustinger

Open Access Theses & Dissertations

Additive manufacturing (AM) has been a maturing technology that has expanded over the course of the last decade in major advancements especially in accessibility, process monitoring, modeling, and stock material design. As its industry use is growing, the demand for added improvements such as multi-functionality increases, such as with a hybrid system that allows for modification of printed parts with different electrical components like the Foundry Multi-3D system. The system's purpose is to create AM parts with multifunctional electrical components with the vision to expand to other areas of interest in manufacturing such as ISAM. This work explores the use …

Fabrication And Performance Of Scalable Bio-Engineered Porous Layers For Efficient Co2 Capture, Mary Sharon Rose Bondugula

Theses and Dissertations

This dissertation addresses the critical challenge of mitigating climate change by advancing CO2 capture technologies. As global CO2 emissions continue to rise, effective methods for capturing and separating CO2 from industrial processes are essential to combat climate change. Existing CO2 capture systems, such as Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA), often rely on packed bed designs that face limitations, including poor heat and mass transfer, slow gas diffusion, and low thermal conductivity, reducing their efficiency. To overcome these challenges, this dissertation explores innovative solutions by developing advanced adsorbent coatings and scalable bed configurations.

This research begins by …

Novel Nanocomposite Of Carbonized Chitosan-Zinc Oxide-Magnetite For Adsorption Of Toxic Elements From Aqueous Solutions, Dalia A. Ali Eng, Ganna Gaber Ismail Eng.

Chemical Engineering

Herein, a novel nanocomposite (carbonized chitosan-zinc oxide-magnetite, CCZF) was developed to effectively remove toxic elements in water remediation. Combining the high adsorption capacities of chitosan with the magnetic properties of magnetite and the chemical stability of zinc oxide, the combination of these unique properties makes it an efficient and versatile material that offers a sustainable solution for water purification. The (CCZF) nanocomposite was synthesized through the coprecipitation method and characterized using various techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and zeta potential analysis. The results showed …

The Impact Of Film Cooling On The Heat Release Within A Rotating Detonation Combustor, Shreyas Ramanagar Sridhara, Antonio Andreini, Marc D. Polanka, Myles D. Bohon

Faculty Publications

Rotating detonation combustors establish a detonation wave that continuously circulates inside a small annulus. The presence of the detonation wave and the downstream oblique shock within the small annulus coupled with high mass flow induces a high heat load to the combustor wall. Preliminary analysis shows that for higher thermal power, internal air cooling alone is not sufficient to remove the heat out of the walls to maintain them below the maximum temperature of the metal. A possible solution is to use film cooling to reduce the heat flux to the combustor walls. One issue, though, is that the introduction …

Efficient Phosphate Removal From Water Using Ductile Cast Iron Waste: A Response Surface Methodology Approach, Mai Hassan Dr., Nada Alkhashab Eng., Ahmed Osman Dr., Dalia A. Ali Eng

Chemical Engineering

Water scarcity is a critical issue worldwide. This study explores a novel method for addressing this issue by using ductile cast iron (DCI) solid waste as an adsorbent for phosphate ions, supporting the circular economy in water remediation. The solid waste was characterized using XRD, XRF, FTIR, and particle size distribution. Wastewater samples of different phosphate ion concentrations are prepared, and the solid waste is used as an adsorbent to adsorb phosphate ions using different adsorbent doses and process time. The removal percentage is attained through spectrophotometer analysis and experimental results are optimized to get the optimum conditions using Design …

A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard

LSU Doctoral Dissertations

The study of gas hydrates has increased significantly over the last two decades because of their potential application in energy storage, production and transportation, water desalination, refrigeration, gas separation, etc. There is a significant interest in commercially developing natural gas hydrates because the energy content of methane hydrate reservoirs (MHRs) is at least twice that of all conventional fossil fuels combined. Additionally, due to the higher storage capacity of hydrates, it is proposed to sequester CO₂ in the form of CO₂ hydrate, thereby reducing the amount of greenhouse gases. Hence, hydrates offer a dual solution to two of …

Green Synthesis Of Carbonized Chitosan-Fe3o4-Sio2 Nano-Composite For Adsorption Of Heavy Metals From Aqueous Solutions, Dalia A. Ali Eng, Rinad Galal Ali Eng.

Chemical Engineering

Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new

nano-composite which was green with …

Constant-Ph Molecular Dynamics At Inorganic Interfaces: Adding A New Dimension To Simulations Of Interfacial Phenomena., Ted Kalbfleisch

Electronic Theses and Dissertations

This dissertation explores the application of novel molecular dynamics simulation methods to better understand complex systems, with a particular focus on silica materials and protein interactions. Silica materials, known for their versatile surface and solution chemistries, play critical roles in catalysis, chromatography, and wastewater treatment. Despite their widespread use, the molecular-level interactions between silica surfaces and their environments remain poorly understood. To address this knowledge gap, we employed λ-dynamics enabled constant pH molecular dynamics to dynamically model protonation and deprotonation events on silica surfaces. Traditional experimental techniques such as x-ray crystallography, NMR, and cryo-EM are inadequate for probing structures in …

Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay

Dissertations

Interactions of powders with high-temperature plasma and shockwaves occur in diverse scenarios, such as nuclear blasts, accidental industrial dust explosions, solid propellant combustion in explosive charges and when removing contaminants from surfaces. Electrostatic Discharge (ESD), known for generating shock and plasma, is a promising lab-scale technique for simulating these interactions. Studies with ESD involved placing powders near a spark-producing gap between electrodes and observing mechanical and chemical processes like particle motion and ignition. A limited range of spark conditions and material properties have been tested, which facilitated the development and validation of preliminary computational models describing this system. Significant gaps …

Smart Manufacturing Of Cement: From Lab-Scale Simulation And Testing To Industry-Scale Deployment., Juan David Tabares Tamayo

Electronic Theses and Dissertations

Cement kilns are controlled by experienced process operators who follow experience-based industry guidelines using data collected and fundamental knowledge. The manufacturing process, which is equipped with sensors and equipment, transfers data/information to the operators to aid standardized decision-making operations. In contrast, companies have used such data to develop and implement digital solutions for predictive control systems; in effect, FLSmidth and Rockwell Automation. However, despite the availability of automated control systems and investigation in automation for process monitoring and optimization, opportunities to radically optimize cement manufacturing are still abundant and in need of implementation. Therefore, this research developed simulation models and …

Improving Static Cold Storage Life Of The Human Heart Before Transplant, Juan Sebastian Rodriguez Paez

Theses and Dissertations

Organ storage and transportation are critical steps for the success of organ transplantation. Static cold storage (SCS) of hearts for heart transplantation (HTx) remains the standard approach. However, SCS may involve damage to the tissue resulting from extended hypothermic preservation, potentially affecting organ viability. More over, the temperature distribution on and within the heart is unknown during heart transplantation. Therefore, there is an interest to study different stages of the heart transplantation process towards determining the 3D temperature distribution on and within the heart. There could be a possibility of having a hypothermic injury in different parts of the heart …

Synthesis Of Durable Zeolite 13x Insertion Coatings And Scaled-Up Experimental Demonstration For Co2 Capture, Daniel Jamil Hocheimy

Theses and Dissertations

Minimizing the energy requirement for capturing carbon dioxide (CO₂) from post-combustion sources is critical to efficient industrial decarbonization and subsequent mitigation of the effects of climate change. The current portfolio of CO₂ capture technologies includes absorption, membrane separation and packed bed adsorption, which suffer from high energy and temperature requirements, scalability, and location dependency issues. Adsorption-based systems could cater to these concerns; however, their current embodiments primarily use packed adsorbent bed design and electricity-driven vacuum pumps to regenerate them. While simple and easy to fabricate, these designs are not scalable and cannot use heat to regenerate them …

Study Of The Effects Of Thermal Aging Coupled With Shot-Peening Treatment Of Carbonitrided Din 1.6587 Low Alloy Steel On Retained Austenite And Residual Stresses, Richard J. Katemi

Tanzania Journal of Engineering and Technology (TJET)

This work investigated the effects of thermal aging and shot-peening of carbonitrided 1.6587 steel grade on retained austenite and residual stresses. After carbonitriding samples contained maximum of 0.87% carbon, 0.34% nitrogen and 50 mass. -% retained austenite. Thermal aging conditions investigated were -30°C, 90°C and 150°C while the aging period were 14, 96 and 720 hours. After thermal aging, some of the samples were subjected to shot-peening treatment using standard cut wire shots StD – G3 - 0.6 mm VDFI 8001 with intensity in the range of 0.25 to 0.30 mmA and coverage of 1.00 to 1.24 x 98%. It …

Assessment Of Risk Factors Related To Body Pain Complaints In Tanzania Construction Industry, Fatma K. Mohamed

Tanzania Journal of Engineering and Technology (TJET)

The construction industry is associated with risks that can result in musculoskeletal diseases. Although young male workers who are presumed to be healthy dominate the industry in Tanzania, body pain complaints have been widely reported. The aim of this study is to assess the prevalence and causes of body pains in workers. A cross-sectional study involving 396 workers was conducted. A chi square test was used for testing association of independent categorical variables and binary logistic regression analysis was used to determine predictors for body pain complaints. The results show that all study participants complained of at least one form …

Effect Of Zr And W Doping On Microstructures, Transition Temperature And Solar Transmittance Modulation Of Thermochromic W/Zr Co-Doped Vo2 Thin Films, Haji F. Haji

Tanzania Journal of Engineering and Technology (TJET)

Thermochromic W/Zr co-doped VO2-based thin films with different concentrations of Zr were successfully deposited on soda lime glass substrates by direct current (DC) magnetron sputtering of V(99)W(01) alloy and Zr targets at a substrate temperature of 425 °C. The films were characterized by x–ray diffraction (XRD), atomic force microscopy (AFM), Rutherford backscattering spectroscopy (RBS), two-point probe and UV/VIS/NIR spectroscopy. The film’s structural properties evolution was significantly influenced by Zr concentration in the films. The transition temperature and hysteresis loop widths of the films were found to decrease with increasing Zr concentration. For the Zr concentrations of 0.21 at.%, 0.23 at.% …

Design And Optimization Of An Azeotropic Distillation Pilot Plant For The Production Of Pure Ethanol, Samwel V. Manyele

Tanzania Journal of Engineering and Technology (TJET)

This study aimed to design an azeotropic distillation plant using Aspen Plus® V10 software and determine optimal process conditions for producing pure ethanol greater than 95% from pre-concentrated near-azeotropic ethanol-water solution. The non-random two-liquid Redlich-Kwong thermodynamic model was the base method for property analysis and performance prediction. Modelling and simulation of the converged process were conducted for fixed column variables (R = 5, N = 12 and p = 1 atm). Plant operating parameters were varied in the range of 0 to 1 for the pre-heater vapour fraction, 2 to 10 for the column feed plates (NFP), 2 to 6 …