Transport Phenomena Commons^™

Investigations Of Air-Water Multiphase Flow In Tubes: Computational Fluid Dynamics, Wei Hong Goo

Student Works (2020-2029)

Mixing is a very crucial process in many industries, such as food processing industry, minerals processing industry, petrochemicals and refining industry, pulp and paper industry, polymer industry, pharmaceuticals industry and many more. There are different types of mixing, such as liquid-gas mixing, liquid-liquid mixing, solid-liquid mixing and many more. The definition of multiphase flow is the simultaneous flow of materials with multiple thermodynamic phases. A lot of process industries require multiphase flows during operation. Bubbly flow is defined as the flow of liquids that contains dispersed gas bubbles. One of the main applications of multiphases flows and bubbly flows is …

Study Of Heat Transfer And Friction Loss Of Nanofluid Suspension Flow In Circular Pipe Heat Exchanger, Ramadas Sandru

Student Works (2020-2029)

This stated experiment focused on the study of convective heat transfer and friction loss in a circular flow passage for Graphene oxide-based nanofluids which are consist of Graphene Oxide/Distilled water with their different wt. % concentrations. These GO/DW based nanofluids where been prepared by using a facile two-step method, while the GO particles were synthesized by a modified hummer method. Four different (0.025, 0.05, 0.075, and 0.1 wt. %) were produced by dispersing graphene particles in distilled water under high probe sonication. The GO/DW based nanofluids flowing in a horizontal shell and tube heat exchanger counter flow under turbulent flow …

Study Of Heat And Momentum Transfer To Colloidal Suspensions In Annular Closed Conduit Flow, Sadik Shoaib

Student Works (2020-2029)

With the advancement of science and the rapid growth of industries and the improved lifestyles of people, energy consumption has been increasing. Whereas the exploration of energy remained at a slower pace and the energy reservoirs are extinguishing at a faster rate. High energy consumption is also encouraging environmental pollution and global warming. Considering all these issues, scientists and engineers are desperately exploring highly efficient heat exchangers for the conservation of energy and minimize its losses. The present research has focused on obtaining highly efficient heat exchangers. Lots of research have performed on the improvement of heat exchanger materials, alteration …

Synthesis Of Eco-Friendly Nanofluids For Enhancement Of Heat Transfer And Application In Different Flow Configuration Passages, Khan Asif

Student Works (2020-2029)

Since the invention of the heat exchangers, the working fluids such as water, ethyl glycol, oil and many others were used, however, they reveal relatively low thermal conductivity. Eco-friendly nanofluids and the cost-effective annular heat exchangers were introduced in this research to overcome the problem. In the present work, heat transfer coefficient and friction loss analyses of (TiO2 and GNP) water-based nanofluids were compared with DI-water flowing in annular conduit under turbulent flow regime. The nanoparticle weight concentrations of 0.1, 0.075, 0.05 and 0.025 wt.% were prepared by using a simple two-step method. The DI-water simulations were conducted by using …

Comparative Analysis Of Simulation Models Of The Production Of Ethylbenzene, Osariemen Imafidon

Honors Theses

Process Engineering is all about making sure a raw material can become the desired product with as little variation as possible, while achieving the customer's specifications. Many equipment used for chemical processes cannot be physically inspected during operation at steady state, hence, the need for simulation software. The objective of this study was to compare the results of three different simulation packages to evaluate their efficacy within process design.

This study focused on the economic analysis of the production of Ethylbenzene using various models. The base case variables were inputted into each model to simulate the calculations for a fully …

Removal Of Fluoride From Mine Water Via Adsorption For Land-Applied Soil Amendment, Michelle Dopp, Kevin Le, Ethan Phan, Mary Johnson, Jacqueline Payne, Adrian Damian, Courtney Golman

Chemical Engineering Undergraduate Honors Theses

The Moo Pig Sooie’s researched, designed, and economically analyzed a full-scale adsorption column system to be applied in mining processes that leave high amounts of fluoride in their effluent. This system was designed to remove fluoride from water saturated with calcium sulfate, as calcium sulfate is present in high amounts in certain mining processes. Currently, high density sludge (HDS) is commonly employed to reduce fluoride concentrations, but due to solubility limits the sludge treatment cannot lower fluoride below 10 mg/L (ppm). The current enforceable EPA standard for discharged water is at 4 mg/L (ppm), although mining companies anticipate that this …

Three-Phase Hydrodynamic Simulation And Experimental Validation Of An Upflow Anaerobic Sludge Blanket Reactor, Camila D' Bastiani, Jéferson Luis Alba, Gabriel Tomazzoni Mazzarotto, Severino Rodrigues De Farias Neto, Anthony Reynolds, David Kennedy, Lademir Luiz Beal

Articles

This research focuses on performing multiphase solid/liquid/gas CFD simulations of a UASB reactor in order to obtain a validated model that provides a clearer understanding of the hydrodynamic behaviour of the three phases in UASB reactors. Eulerian–Eulerian, laminar, three-dimensional, multiphase simulations are carried out using Fluent 16.2. The liquid phase velocity and flow profile are validated through PIV experiments. A liquid mean velocity difference of 8.45% is found between the experimental and numerical results, thus validating the CFD model. Shadowgraphy is applied successfully to validate the biogas phase velocity and bubble size. Based on the hydrodynamic analysis results, the reactor …

Dry And Wet Torrefaction Of Microalgal Biomass For Biochar Production As Bioenergy Sources, Yong Yang Gan

Student Works (2020-2029)

Increasing population in global and living standards have risen the consumption of global energy. Thermochemical conversion approaches hold great potential for the biomass conversion into energy applications. Among these approaches, torrefaction is a promising technique to enhance the biomass properties, making it more practical and suitable in biofuel applications. In this study, two different species of microalgae (third generation biofuel feedstock) including Chlorella vulgaris ESP-31 and FSP-E were used as feedstocks for dry and wet torrefaction. Dry torrefaction of microalgae was performed at temperatures of 200, 250 and 300 ºC, and holding times of 15, 30, 45 and 60 min, …

The Desorption Kinetics Of Methane From Nonaqueous Fluids For Enhanced Well Control, James Lee Nielsen Jr.

LSU Master's Theses

The mass transfer of a dissolved gas evolving to return to the gaseous phase from a liquid is governed by many parameters. This process affects the development of an oil and gas well due to the possibility of gas contamination occurring from either an influx entering the wellbore, or drilling through gas-bearing formations. Once this dissolved hydrocarbon gas circulates up the wellbore, it will begin to evolve from solution and poses a potential risk to drilling equipment, the environment, and personnel at a drilling rig. Being able to predict the behavior of gas desorption based on a known set of …

A Study Of Particle-Laden Flows From Meso And Micro-Scale Perspectives, Daniel Guedes De Oliveira

LSU Doctoral Dissertations

Particle-laden flows are investigated numerically from a meso-scale perspective using Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) and from a micro-scale perspective using Particle Resolved Direct Numerical Simulation (PR-DNS). For the former, the dynamics of a pseudo-2D pulsed fluidized bed (PFB) consisting of 400,000 to 800,000 particles was investigated (Chapters 2 and 3). The focus is on the capabilities of CFD-DEM to (1) reproduce pattern formation in these systems and (2) further the understanding of the dynamics of PFB's as a function of pulsation parameters. In Chapter 4, a two-spheres system is investigated with a recently implemented PR-DNS …

Enhancing Protection Of Vehicle Drivers And Road Safety By Deploying Adas And Facial Features Pattern Analysis (Ffpa) Technologies, Raymond Sze Wai Fu, Xueying Wang, Antonio Wong, Chi-Wing Tsang

Faculty of Science & Technology (THEi)

The latest technology associated with Intelligent Transportation Systems (ITS) have been designed with the aim to minimize the numbers of person injury in road accidents and improve the overall road safety. The driver behavior is one major concern in many accidents in HK urban road links. In particular, the driver's attitudes, such as fatigue, drowsiness and concentration are the major causes to road accidents. It will affect the driver's ability and decisions in properly controlling their vehicles. Very often, this kind of driver distraction is particularly obvious when driving after 2 to 3 hours from most research sources. In the …

Towards Efficient Water Treatment: Mechanism Of Colloidal Fouling Of Ultrafiltration Membranes, Ikenna Henry Ozofor

Dissertations, Master's Theses and Master's Reports

This research study first reviewed challenges of conventional and membrane separation systems for water treatment. Though membrane separation systems appeared superior to the conventional counterparts for water and wastewater treatment, wider applications of membrane systems have been limited by some factors, most notably is membrane fouling. Experimental studies were therefore conducted to achieve the goal of this research, which is to investigate how feed properties affect fouling of ultrafiltration (UF) membranes by colloids.

Feed salinity, pH, and nanoparticle concentration were the variables studied to unravel how different UF membranes are fouled by model silica colloids (with average diameter of 25nm). …

Virus Purification Framework And Enhancement In Aqueous Two-Phase System, Pratik Umesh Joshi

Dissertations, Master's Theses and Master's Reports

Viral infections regularly pose detrimental health risks to humans. Preventing viral infections through global immunization requires the production of large doses of vaccines. The increasing demand for vaccines, especially during pandemics such as COVID-19, has challenged current manufacturing strategy to develop advanced unit operations with high throughput capability. Over the decade, the upstream processing responsible for synthesizing viral products in cell cultures has shown significant success in yielding high titers of viruses and virus-like particles. The progress in the upstream stage has now shifted the bottleneck to the downstream processing (DSP). Overlooked for decades, the DSP responsible for viral product …

A Comparison Of Fiber Mat Thickness Measurement Techniques Using Laser Interferometry And Water Displacement, Ryan Seabeck

Williams Honors College, Honors Research Projects

Polymer fiber mats may often be very thin which leads to complications in measuring thickness. The thickness of fiber mats, however, is crucial in understanding their behavior. Thickness affects how well the mat works as a filter as well as the pressure drop across the mat, and herein lies the need for accurate measurement techniques. Currently two of the available techniques for measuring mat thickness are by laser interferometry[1] and by buoyancy force when submerged in water[2]. Instead of measuring the buoyancy force in this experiment, an enclosure intended to measure the thickness via water displacement was …

Chloride Effect In Fly Ash Geopolymer Cement, Evan Dimmick

Williams Honors College, Honors Research Projects

The production of ordinary portland cement (OPC) poses a significant impact on the world's carbon dioxide emissions through the wide global use of concrete. Geopolymer cements (GPC) made from alkali activated fly ash can serve as a replacement to OPCs, reducing the carbon dioxide emissions by as much as 80%. GPCs exhibit adequate or superior mechanical performance to OPCs. The corrosion of carbon steel rebar in concrete occurs largely from chloride ion attack. The focus of this project will be to experimentally determine the coefficient of diffusion for chloride ions in GPCs and OPCs and compare to the corrosion performance …

A Foundational Approach To Extrusion And Compounding, David Frankart

Williams Honors College, Honors Research Projects

With a history of nearly 200 years, polymer processing and compounding is constantly changing to fit the material science needs of the era. Exposure of undergraduate students to the technology and practices used in industry today in a lab setting would create new opportunities for experiential learning and growth. The objective was to set up a 0.75”, 25 L/D Thermo Haake single screw extruder for lab use and run trials of material in a single screw extruder to set up a basis for experiments. Trials were run of co-polyester resin through a single screw extruder with carbon fiber additives varying …

Capillary Forces And Wetting Dynamics By Diffuse-Interface Modeling, Fanny Thomas

Dissertations and Theses

Wetting phenomena underlie many natural and industrial processes, from the proper functioning of the lungs to the thin coating of surfaces. The three-phase interactions involved at microscopic scales play a critical role. Adding solid particles to an emulsion, for example, can drastically change the flow behavior due to capillary bridging between the particles. The study of these three-phase systems is especially relevant to the petroleum industry, where gas hydrates forming large clusters in subsea pipelines during crude oil transportation is a major concern. The dynamics of such systems is also of great interest from a fundamental perspective. Indeed describing non-equilibrium …

Process Modeling And Techno-Economic Analysis Of Thermo-Catalytic Dimethyl Ether Synthesis And Microwave-Based Aromatics Production Technologies From Shale Gas, Chirag Mevawala

Graduate Theses, Dissertations, and Problem Reports (ETD)

Production of dimethyl ether (DME) and direct non-oxidative methane dehydroaromatization (DHA) to aromatics via conventional and microwave (MW)-assisted processes are investigated in this research. Plant-wide models of the shale gas to DME process with integrated CO₂ capture via direct and indirect synthesis routes have been developed. Optimal parameter estimation, and model validation are undertaken for various sections of the process including the pre-reforming reactor, auto-thermal reforming reactor, DME synthesis reactors, CO₂ capture units and separation sections. A novel DME separation process has been developed for efficient separation of DME, syngas, and CO₂. Plant-wide techno-economic optimization is …

Elucidating The Properties And Mechanism For Cellulose Dissolution In Tetrabutylphosphonium-Based Ionic Liquids Using High Concentrations Of Water, Brad Crawford

Graduate Theses, Dissertations, and Problem Reports (ETD)

The structural, transport, and thermodynamic properties related to cellulose dissolution by tetrabutylphosphonium chloride (TBPCl) and tetrabutylphosphonium hydroxide (TBPH)-water mixtures have been calculated via molecular dynamics simulations. For both ionic liquid (IL)-water solutions, water veins begin to form between the TBPs interlocking arms at 80 mol % water, opening a pathway for the diffusion of the anions, cations, and water. The water veins allow for a diffusion regime shift in the concentration region from 80 to 92.5 mol % water, providing a higher probability of solvent interaction with the dissolving cellulose strand. The hydrogen bonding was compared between small and large …

Formulation And Validation Of Nanoparticle Controlled Delivery For Chemotherapeutic Drug Products, Shani L. Levit

Theses and Dissertations

Taxol, a formulation of paclitaxel (PTX), is one of the most widely used anticancer drugs, particularly for treating recurring ovarian carcinomas following surgery. Clinically, PTX is used in combination with other drugs such as lapatinib (LAP) to increase treatment efficacy. Delivering drug combinations with nanoparticles has the potential to improve chemotherapy outcomes. In this study, we use Flash NanoPrecipitation, a rapid, scalable process to encapsulate weakly hydrophobic drugs (logP in vitro. Encapsulating either PTX or LAP into nanoparticles increases drug potency. When PTX and LAP are co-loaded in the same nanoparticle, they have a synergistic effect that is greater than …

Beneficiation Of Coal Using Supercritical Water And Carbon Dioxide Extraction, Matthew Decuir Virginia Commonwealth University Cl

Theses and Dissertations

This work explores the use of carbon dioxide, water, and their mixtures as solvent for the pre-combustion beneficiation of raw coal without using any toxic mineral acids in the temperature range of 200-400℃. The fluid polarity, ionic constant, and supercritical point can be adjusted by H₂O/CO₂ ratio and temperature. Adding carbon dioxide to hydrothermal fluid also increases the ionization by forming carbonic acid. Extractions with supercritical fluids have several benefits including enhanced mass transport, ease of separation and recycle, wide range of extractive capability and tunability, better inherent safety, and in the case of carbon dioxide and …

Modeling Of Rotary Packed Beds For Reactive And Non-Reactive Systems, Chinyere Evangeline Ezeobinwune

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rotary packed beds (RPBs) are used in a wide range of reactive and non-reactive applications. In this research, a 2-d, first-principles, dynamic model of a non-reactive RPB that is used for heat exchange between the outgoing flue gas from a power plant and the incoming air to the boiler/pulverizer of the power plant is developed. A 2-d, first-principles model of a reactive RPB is developed where a functionalized metal-organic framework (MOF) is used for CO₂ capture.

For the non-reactive system, a Ljungstrom-type air preheater (APH) is considered. Existing models for these rotating heat exchangers are typically 1-d. There are …

Non-Invasive Detection And Assessment Of Coronary Stenosis From Blood Mean Residence Times., Javad Hashemi

Electronic Theses and Dissertations

Coronary artery stenosis is an abnormal narrowing of a coronary artery caused by an atherosclerotic lesion that reduces lumen space. Fractional flow reserve (FFR) is the gold standard method to determine the severity of coronary stenosis based on the determination of rest and hyperemic pressure fields, but requires an invasive medical procedure. Normal FFR is 1.0 and FFR RT, to account for varying volume and flow rate of individual segments. Blood_RT was computed in 100 patients who had undergone the pressure-wire FFR procedure, and a threshold for Blood_RT was determined to assess the physiological significance of a stenosis, …

Applications Of Ionic Liquids In Membrane Separation, Mohanad Kamaz

Graduate Theses and Dissertations

Ionic liquids represent an emerging attractive material in membrane technology. The central theme of this doctoral dissertation is to develope novel membranes using ionic liquids. Two different approaches were used to prepare ionic liquid membranes including the immobilization of ionic liquid within the membrane pores or the use of pressure assembly method to deposit a selective ionic liquid layer on the top membrane surface.

In chapter 2, imidazolium ionic liquids with three different alkyl halides were successfully synthesized and used to prepare supported ionic liquid membranes (SILMs). SILMs preraper were tested for aqueous and nonaqueous applications. For nonaqueous applications, the …

Breaking Coastal Hypoxia: Destratification Of Gulf Of Mexico Deadzone To Encourage Oxygen Transport Downwards To Maintain Marine Fauna, Veda Thipparthi

LSU Master's Theses

As a consequence of seasonal eutrophication and human input, a vast hypoxic area termed The Dead Zone develops every year in the Gulf of Mexico (GOM) during summer along the Louisiana coastline characterized by vertical seawater density-stratification with oxygen concentrations less than 2 mg.l^-1 at the seafloor. It poses a threat to bottom-dwelling faunae and their environment which has negative ecological and economic consequences. This project aims to mitigate hypoxia by employing mechanical impellers placed at strategic water depths and locations in the Gulf. Enhanced transport of oxygen results by mixing oxygen-enriched seawater at the surface, downward into the …

Amélioration De La Justesse Des Modèles D’Hygiène Du Travail Utilisés Pour Estimer Des Expositions Professionnelles À Des Vapeurs De Solvants, Spéro Abattan, Stéphane Hallé, Daniel Drolet, Ali Bahloul, Patrick Eddy Ryan, Wejden Chouchene, Carlos Castro Ruiz, Jérôme Lavoué, Maximilien Debia

Rapports de recherche scientifique

Chaque année, des travailleurs québécois subissent des effets sur leur santé après avoir été exposés à des substances chimiques, notamment à des solvants. La modélisation des expositions professionnelles occupe une place importante dans la prévention des risques. Cette recherche vise à étudier différents aspects de la modélisation pour estimer des expositions professionnelles à des vapeurs de solvants dans le but d’en améliorer la justesse de prédiction. Le travail de recherche a été effectué en deux volets. Grâce à la mise en œuvre de tests à petite échelle (volet I) et à échelle humaine (volet II), les travaux présentés dans cette …

A Kinetic And Thermodynamic Model Of Ethylene Dichloride Pyrolysis., Travis J Czechorski

Electronic Theses and Dissertations

Ethylene dichloride (EDC) is a precursor for the production of vinyl chloride (VCM) which is subsequently polymerized to form polyvinyl chloride (PVC). To convert EDC to VCM, EDC undergoes a pyrolysis process in the absence of oxygen at temperatures exceeding 500C. However, process yields are limited by the uncontrolled production of side-products that can degrade the quality of PVC and poison the reactor. Thus, tight process controls and costly separations guided by heuristics and plant operator experience are used to optimize EDC pyrolysis. To improve the process, I have programed a kinetic model of EDC pyrolysis based upon estimations of …

Multiphase Cfd Modeling In Particle-Laden Flows, Zhizhong Ding

LSU Doctoral Dissertations

Multiphase modeling is prevalent and useful in solving problems involving multiphase interactions such as fluid and solid. Applications conclude but not limited to fluidized bed, hydraulic conveying, and many others. Modeling techniques with multiple scales can provide various states of details with diverse computational resources used. In this dissertation, two CFD multiphase models are used to disclose interaction details in the particulate system. Two-Fluid Model is used to solve pulsed fluidized bed problem and immersed boundary method based direct numerical method is used to solve particle’s behavior in shear flow. Getting a better understanding of these problems to help to …

Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu

Mechanical Engineering Research Theses and Dissertations

My research focuses on electrokinetic transport. Particularly, in this dissertation, we focus on fabrication and testing of micro electrodes with nanostructured surfaces to minimize the electrode polarization (EP) effects for biosensor applications. In the first study, electrochemical deposition of gold nanoparticles on to planar gold electrodes was used to generate rough surfaces. Dendritic nanostructures that reduced EP up to two orders of magnitude was obtained by optimizing the deposition conditions. These structures also enhanced dielectrophoresis (DEP) response of our bio-chips, making them usable in physiological buffers. In further studies we discovered a universal scaling of EP in the frequency domain, …

A Numerical Simulation Optimizing Droplet Motion Driven By Electrowetting, Jake M. Lesinski

Master's Theses

A numerical simulation of electrowetting on a dielectric was performed in COMSOL to grant insight on various parameters that play a critical role in system performance. The specific system being simulated was the Open Drop experiment and the parameters being investigated were the applied voltage, contact angle at the advancing triple point, and droplet overlap onto neighboring actuated electrodes. These parameters were investigated with respect to their effect on droplet locomotion performance. This performance was quantified by the droplets velocity and the dielectrophortic (DEP) force’s magnitude; the DEP force was calculated from integration of the Maxwell Stress Tensor, however, the …