Transport Phenomena Commons^™

Application Of Pinch Analysis For Energy Saving And Reducing Gas Emissions Based On Mathematical Model In The Hydrocracking Unit, Badiea S. Babaqi

Hadhramout University Journal of Natural & Applied Sciences

Pinch analysis approach of the heat exchanger network in the hydrocracking unit was carried out to save the energy consumption and reduce the gas emissions simultaneously. This method based on mathematical model of the hydrocracking unit for a heat exchanger network using LINGO program to achieve the minimization of environmental impacts and the reduction of energy cost. The presented energy demands for the heat exchanger network are 20.38 MMBtu/hr and 26.52 MMBtu/hr for heating and cooling loads, respectively. The current analysis shows a huge opportunity in order to decrease energy consumption of the hydrocracking process at a minimum temperature difference …

Operation And Preliminary Energy Balance Of A Portable Kelp Dryer In Maine, Tuqa Al-Asadi

Electronic Theses and Dissertations

Seaweed (macroalgae) is a marine resource that has a high economic value. Seaweeds are important commodities as raw material for food or additives and as a source of biomass. One popular species of seaweed is Sugar kelp (Saccharina latissima) – a brown algae that is native to the Maine coast and also a commonly farmed species. It is a rich source of fibers, vitamins, minerals, and antioxidants. Seaweeds are highly perishable due to their high moisture content and will spoil quickly if not preserved, therefore a common practice is to dry the product to prolong storage life and to minimize …

Scale Modeling Of An Appearance Of Downwash Pattern Of Hot Smoke Ejected From Chimney In The Turbulent Cross Flow, Xangpheuak Inthavideth, Nobumasa Sekishita, Sounthisack Phommachanh, Yuji Nakamura

Progress in Scale Modeling, an International Journal

This study aims to elucidate the scaling law to provide the critical condition on appearance of the downwash pattern of the hot smoke ejected from a chimney in a turbulent cross flow. A specially designed wind tunnel with an active turbulence generator developed by Makita was adopted to offer a quasi-isotropic turbulence field in a lab-scale test facility. A heated jet with smoke is issued into the cross flow from the vertically oriented chimney placed in the test section of the wind tunnel. In this study, the experimental parameters considered are temperature of the heated jet (smoke), jet ejected velocity, …

Method For Routine Density Measurement Of Sublimating Solid Carbon Dioxide (Dry Ice) For Cold-Chain Quality Control, Kimberly Hafner, Bruce A. Welt, William Pelletier

Journal of Applied Packaging Research

With recent development of vaccines and biologics, interest in dry ice for cold chain shipping has increased. However, understanding of how dry ice properties relate to performance is not well understood. This study introduces a simple method for measuring a key property of dry ice that has been shown to correlate to performance. The method involves a variant of the water displacement method for determining volume, where dense solid particles are used in place of water for volume determination. Three particle types (sieved sand, glass beads, and stainless-steel shot) were tested for suitability with the particle displacement method. Items of …

Diffusion Of A Salt In An Aqueous Media, Aldaly Pineda Hernandez

Chemical Engineering Undergraduate Honors Theses

Diffusion is defined as the net transfer of a molecule from a high concentration region to a low concentration region. The concept of diffusion is used in a very important process called "desalination." Desalination is a separation process used to reduce the salt content dissolved in brackish water to make it suitable for human consumption, irrigation, and industrial use.

In desalination plants, it is important to monitor the constantly changing salt content of water, partly due to the diffusive effect. The main purpose of this experiment was to study the diffusion of NaCl in water at two NaCl concentrations. The …

Free Convection Heat Transfer From Plates, Alexa Moreno

Chemical Engineering Undergraduate Honors Theses

The purpose of this honors thesis is to create an experiment for the CHEG Lab I course. This report explains the motivation for creating this heat convection experiment, the results of performing the experiment, and provides recommendations for future work on this experiment. Multiple experiments were performed to assess materials and parameters to be investigated. It was determined that a 0.5” plate has smaller percent error and accommodates for the desired timeframe for a Lab I experiment compared to the first plate used (1.5” thickness). Recommendations for expanding on this project include adding experiments using vertical geometry for heat convection …

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …

Structural, Charge Transport, Gas Sensing, Magnetic, Pseudocapacitive, And Electrocatalytic Properties Of Perovskite Oxides., Surendra Bahadur Karki

Electronic Theses and Dissertations

Perovskites are functional materials with the general formula ABO₃ (A = alkali, alkaline earth or lanthanoid cations and B = transition metal or main group cations). These materials are marked by a variety of crystal structures and interesting properties such as colossal magnetoresistance, ferroelectricity, multiferroicity, superconductivity, pseudocapacitance, gas sensing, charge transport, and electrocatalytic properties. The formula of perovskite can be written as AA’BB’O₆, when there is ordering between two cations over A and B-sites. Such compounds are called double perovskite oxides. Some amount of oxygen could be lost from crystal structure without decomposition of the phase. Such …

Development & Validation Of A Piv System For Obtaining Data From A Uasb Reactor, Camila D' Bastiani, Gerald Gallagher, David Kennedy, Anthony Reynolds

Conference Papers

Anaerobic digestion processes can generate energy in the form of biogas while treating organic wastewater. The efficiency of the treatment, and thus the generation of biogas, is closely linked to the type and design of the reactor, and the technology used. Granular anaerobic digestion technology offers advantages such as a higher loading rate and reduction of the space needed. However, the hydrodynamics inside this type of reactor can be complex due to the presence of solids (granules) and gas (biogas) phases along with the liquid phase (wastewater). This is one of the reasons why the study and optimization of reactors …

Tuning Electrochemical Interactions And Polymer Electrolyte Interfaces For Enhanced Organic Acid Separations Using Electrodeionization, Matthew Leo Jordan

LSU Doctoral Dissertations

Chemical separations are critical processes for chemical and industrial plants to purify and isolate products however current separation technologies, such as distillation, rely on energy intensive processes. Electrochemical separation processes, such as electrodialysis and electrodeionization, are an energy efficient alternative that are emerging as an alternative for thermal-based separations. Organic acids are weakly ionizable species and susceptible for purification from process streams using electrochemical processes. Recently the fermentation route has garnered greater attention as a means for producing value-added chemicals, such as organic acids, from a renewable feedstock and aiding the circular economy. Some of the challenges electrodialysis faces for …

Droplets In An Electric Field: Surface Rheology, Coalescence And Rebound, Yu Han

Dissertations and Theses

Electrocoalescence is the process in which pairs of conducting droplets suspended in a continuous dielectric (nonconducting) liquid phase are drawn together and merge upon the application of an electric field. The electric field polarizes each of the droplets in the field direction. The polarization causes the drops to deform and drives a dipolar attraction which forces them to approach each other and coalesce. Many technologies use electric fields to manipulate fluid dispersions. Electrocoalescence is an essential unit operation for separating water droplets in a crude oil. This water in oil emulsion is stabilized by surfactants, such as asphaltenes, resins and …

Development Of Advanced Models For Pre-Ignition Prediction In Gas Engines And Analytical Model For Wallfilm Evaporation, Ankith Ullal

Dissertations, Master's Theses and Master's Reports

Ever-changing regulations aimed at improving efficiency and reducing harmful emissions have resulted in many power-generation device (engine) manufacturers to adopt new strategies. Computer simulation of these new strategies of power generation requires more accurate and higher fidelity modelling tools. In the present study, two such models are developed. The first model deals with pre-ignition phenomena driven by lubricant (lube) oil in natural gas engines and the second model is relevant to prediction of wallfilm evaporation by employing analytical solutions to transport governing equations for boundary layers.

Pre-ignition in engines has been the subject of current research with the advent of …

Design And Control Of Intensified Membrane Reactor Systems Through Module-Based Design Approach, Brent Bishop

Graduate Theses, Dissertations, and Problem Reports

As interest in the modularization and intensification of chemical processes continues to grow, more research must be directed towards the modeling and analysis of intensified process units. Intensified process units such as membrane reactors pose unique challenges pertaining to design and operation that have not been fully addressed in the reported literature. This work aims to address the design and control challenges caused by the integration of phenomena and the loss of degrees of freedom (DOF) that occur in the intensification of modular membrane reactor units.

First, a novel first-principles approach for modeling membrane reactors is developed using the AVEVA …

Numerical Investigation On The Effect Of Spectral Radiative Heat Transfer Within An Ablative Material, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

The spectral radiative heat flux could impact the material response. In order to evaluate it, a coupling scheme between KATS - MR and P1 approximation model of radiation transfer equation (RTE) is constructed and used. A Band model is developed that divides the spectral domain into small bands of unequal widths. Two verification studies are conducted: one by comparing the simulation computed by the Band model with pure conduction results and the other by comparing with similar models of RTE. The comparative results from the verification studies indicate that the Band model is computationally efficient and can be used to …

Preliminary Development Of The Dialysis-Membrane-Based Passive Biocide Delivery System For Spacecraft Water Recovery Units, Rogelio Elias Garcia Fernandez

Graduate Theses and Dissertations

The purpose of this investigation is to explore the capabilities of a dialysis-membrane-based system for the in-line dosing of silver ions to treated water in spacecraft water recovery units. The spacecraft environmental control and life support system community (ECLSS) are interested in adopting silver ions as a biocide in future spacecraft water recovery processes since silver ions are effective biocide at concentrations that humans can safely consume. The system has been designed following the configuration of the Water Processor Assembly (WPA) aboard the International Space Station. In this configuration, silver ions have to be added at the last step in …

Water Recovery From Bioreactor Mixed Liquors Using Forward Osmosis With Polyelectrolyte Draw Solutions, Calen Raulerson

All Theses

The objective of this research was to test the feasibility of using forward osmosis (FO) with polyelectrolyte draw solutions to recover water from bioreactor mixed liquors. When combined with an Anaerobic Osmotic Membrane Bioreactor (AnOMBR), such a system could process fecal and food waste from astronauts aboard the International Space Station (ISS) and reclaim important nutrients and water. This project focused on measuring the obtainable water recovery rates from bioreactor effluent, and the identifying challenges associated with the operation.

AnOMBRs feature several advantages over aerobic bioreactors, and non-osmotic anaerobic membrane bioreactors (AnMBR). Anaerobic bioreactors avoid the significant energy costs of …

Towards Long Term Colloid Suspension In A Vertically Rotated System., Md Mahmudur Rahman

Electronic Theses and Dissertations

Within a colloidal suspension gravity may compromise the observation of governing physical interactions, especially those that are weak and/or take significant time to develop. Conducting the experiment in a long-term microgravity environment is a viable option to negate gravitational effects, though significant resources are required to do so. While it may not be possible to simulate long-term microgravity terrestrially, particles can resist quick sedimentation in a confined suspension system rotating vertically with appropriate rotation speed. The goal of the investigation is to demonstrate the existence of long-term particle suspension regime for a certain colloidal suspension while characterizing colloidal behavior due …

Cfd Simulations Of Macroscopic And Microscopic Multiphase Fluid Flow And Droplet Interaction, Aaron Harrington

LSU Master's Theses

Multiphase flow is a complex phenomenon which can be modeled on numerous different length scales, both macroscopically and microscopically. The use of a Euler-Euler model for Computation Fluid Dynamics (CFD) simulations of subcooled boiling phenomena is discussed in detail. The CFD conditions have been set up to mimic previous experimental conditions. A cylindrical vessel with subcooled liquid flow is heated along part of the axial wall of the vessel. A constant heat flux is applied to produce subcooled boiling. We discuss the development of the phase change within the vessel as well as the temperature profile, and validate the results …

Spatiotemporal Metabolic Modeling Of Pseudomonas Aeruginosa Biofilm Expansion, Robert Sourk

Masters Theses

Spatiotemporal metabolic modeling of microbial metabolism is a step closer to achieving higher dimensionalities in numerical studies (in silico) of biofilm maturation. Dynamic Flux Balance Analysis (DFBA) is an advanced modeling technique because this method incorporates Genome Scale Metabolic Modeling (GSMM) to compute the biomass growth rate and metabolite fluxes. Biofilm thickness is pertinent because this variable of biofilm maturation can be measured in a laboratory (in vitro). Pseudomonas aeruginosa (P. aeruginosa) is the model bacterium used in this computational model based on previous research conducted by Dr. Michael Henson, available GSMMs, and the societal significance of patients suffering from …

Metabolic Modeling Of Bacterial Co-Cultures For Co-To-Butyrate Conversion In Bubble Column Bioreactors, Naresh Kandlapalli

Masters Theses

One of the most promising routes to renewable liquid fuels and chemicals is the fermentation of waste carbon by specialized microbes. Commercial development of gas fermentation technology is underway but many fundamental research problems must be addressed to further advance the technology towards economic competitiveness. This thesis addresses the important problem of developing integrated metabolic and transport models that predict gas fermentation performance in industrially relevant bubble column reactors. The computational models describe the conversion of CO-rich waste streams including synthesis gas to the platform chemical butyrate. The proposed modeling approach involves combining genome-scale reconstructions of bacterial species metabolism with …