Papers by Brigette Rosendall, PhD
Materials Today: Proceedings, 2020
Numerical simulation has been carried to study the influence of impingement angle due to air born... more Numerical simulation has been carried to study the influence of impingement angle due to air borne particle erosion on glass fiber reinforced polymer (GFRP) composites and validated experimentally. In the experiment setup, air-jet erosion test-rig is used, in which erodent particles are striking at different impingement angles of 15°, 30°, 45°, 60°, 75°and 90°with impact velocity of 25 m/s. For the computational fluid dynamics modelling of erosion behavior, the Discrete phase Model (DPM) for tracking the particle and oka's model for composite erosion are used in ANSYS Fluent. The results of steady state experiment show that erosion rate of glass fiber reinforced composite is low at 15°impingement angle and maximum value is found in between 30°to 90°impingement angles, which reveals semi ductile behavior of fabricated composite. The Numerical simulation erosion response on glass fiber reinforced polymer composite at different impingement are in good agreement with experiments.
In presenting this thesis in partial fulfillment of the requirements for a Master's degree at the... more In presenting this thesis in partial fulfillment of the requirements for a Master's degree at the University of Washington, I agree that the Library shall make its copies freely available for inspection. I further agree that extensive copying of this thesis is allowable only for scholarly purposes, consistent with "fair use" as prescribed in the U.S. Copyright Law. Any other reproduction for any purposes or by any means shall not be allowed without my written permission.
the University of Washington, I agree that the Library shall make its copies freely available for... more the University of Washington, I agree that the Library shall make its copies freely available for inspection. I further agree that extensive copying of this thesis is allowable only for scholarly purposes, consistent with "fair use " as prescribed in the U.S. Copyright Law. Any other reproduction for any purposes or by any means shall not be allowed without my written permission.
Abstract—Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many d... more Abstract—Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many diseases, such as stroke, multiple sclerosis, neuromuscular diseases, and cancer. Its complications include choking, aspiration, malnutrition, cachexia, and dehydration. The goal in dysphagia manage-ment is to provide adequate nutrition and hydration while minimizing the risk of choking and aspiration. It is important to advance the individual toward oral feeding in a timely manner to enhance the recovery of swallowing function and preserve the quality of life. Current clinical assessments of dysphagia are limited in providing adequate guidelines for oral feeding. Mathematical modeling of the fluid dynamics of pharyn-geal bolus transport provides a unique opportunity for studying the physiology and pathophysiology of swallowing. Finite element analysis (FEA) is a special case of computa-tional fluid dynamics (CFD). In CFD, the flow of a fluid in a space is modeled by covering the space wi...
The Columbia River in Washington State is threatened by the radioactive legacy of the cold war. T... more The Columbia River in Washington State is threatened by the radioactive legacy of the cold war. Two hundred thousand cubic meters (fifty-three million US gallons) of radioactive waste is stored in 177 underground tanks
WIT transactions on engineering sciences, 2005
Concurrent liquid-gas flow manifests itself into different flow regimes depending on fluid proper... more Concurrent liquid-gas flow manifests itself into different flow regimes depending on fluid properties, flow rates, heat inputs and geometry. The Baker chart has identified at least seven flow regimes, viz. stratified, wavy, plug, slug, annular, dispersed and bubbly flow. Each flow regime exhibits a unique flow pattern and may transition from one to another depending on the flow conditions in the pipe. Computational Fluid Dynamics (CFD) with multiphase flow equations add a capability by which these flow regimes can be visualized and understood. In this paper stratified and slug flow regimes are studied by using CFD modeling. The modeling results are validated by comparison with published experimental data. The benchmark comparison shows that CFD is successful in predicting the following aspects in two-phase flow: • Quantitative prediction of stream-wise velocities in both phases. • Qualitative prediction of flow regime, phase distribution and pressure distribution. • Transition betwe...
Transactions of the American Nuclear Society, 2008
Thesis (Ph. D.)--University of Washington, 1996 A significant portion of the population suffers f... more Thesis (Ph. D.)--University of Washington, 1996 A significant portion of the population suffers from difficulty in swallowing, known as dysphagia, including 12 to 13% of hospitalized patients and 40% of nursing home residents. Dysphagia can make it impossible for a person to eat and drink normally which can lead to malnutrition, cachexia, and dehydration. During the pharyngeal phase of swallowing, the food or liquid to be swallowed, known as the bolus, passes the entrance to the larynx. If the bolus penetrates into the larynx, aspiration or choking can occur. Chronic aspiration can lead to serious lung infections such as pneumonia. Approximately 8,000 people in the United States choke to death each year.In this research, a mathematical model that simulates swallowing was developed to analyze the parameters affecting the transport of the bolus through the pharynx. This work is a first attempt at modeling the pharyngeal phase of swallowing. The pharyngeal phase of swallowing is a comp...
The Columbia River in Washington State is threatened by the radioactive legacy of the cold war. T... more The Columbia River in Washington State is threatened by the radioactive legacy of the cold war. Two hundred thousand cubic meters (fifty-three million US gallons) of radioactive waste is stored in 177 underground tanks (60% of the nation's radioactive waste). This waste is a product of 50 years of plutonium production for national defense. Bechtel National, Inc (BNI) has been commissioned by the U.S. Department of Energy to design and build a vast complex of waste treatment facilities to convert this waste into stable glass using a proven vitrification process. The waste in these underground storage tanks is a combination of sludge, slurry, and liquid. Part of the engineering challenge for during processing is to verify that mixing systems in the plant vessels keep all solids in suspension. For various reasons, the mixing system chosen is one based on jet mixers. Specifically, these vessels use compressed air driven pumps to power what are known as pulsed-jet mixers (PJMs). Comp...
Computer-based engineering tools such as computational fluid dynamics (CFD) provide tremendous in... more Computer-based engineering tools such as computational fluid dynamics (CFD) provide tremendous insight into flow details that are inaccessible using simpler approaches. Used in conjunction with a well-founded verification and validation (V&V) process, these details enable improved engineering designs with tighter margins and reduced costs. Wherever the potential for high risk/exposure exists and design uncertainty must be reduced, CFD is an enabling technology. This paper presents three illustrations of how CFD models can be applied to gas-solid, gas-liquid, and solidliquid multiphase flow problems. Two cases show how CFD can be applied to engineering projects and how validation data is used to add confidence to the model predictions. The third case specifically illustrates how validation is used to improve the process of building a CFD model. Together, these illustrations are indicative of how Bechtel is at the cutting edge of bringing multiphase CFD into mainstream engineering.
Journal of Fluids Engineering, 2015
A method to assess computational fluid dynamics (CFD) models for polydisperse granular solids in ... more A method to assess computational fluid dynamics (CFD) models for polydisperse granular solids in a multifluid flow is developed. The proposed method evaluates a consistency constraint, or a condition that an Eulerian multiphase solution for a monodisperse material in a single carrier fluid is invariant to an arbitrary decomposition into a pseudo-polydisperse mixture of multiple, identical fluid phases. The intent of this condition is to develop tests to assist model development and testing for multiphase fluid flows. When applied to two common momentum exchange models, the constraint highlights model failures for polydisperse solids interacting with a multifluid flow. It is found that when inconsistency occurs at the algebraic level, model failure clearly extends to application. When the models are reformulated to satisfy the consistency constraint, simple tests and application-scale simulations no longer display consistency failure.
Pulse Jet Mixers are designed at the Hanford Site Waste Treatment Plant to keep radioactive solid... more Pulse Jet Mixers are designed at the Hanford Site Waste Treatment Plant to keep radioactive solids in suspension prior to vitrification for permanent storage. These systems must operate dependably and without maintenance for 40 years or more. The existing design database for pulse jet mixing of slurries like those at Hanford is meager. Verified/validated low-order design tools do not exist that can be used to reliably predict the operating conditions under which the Hanford slurry will successfully achieve suspension. This study presents the results of a coupled CFD/analytical effort to develop a low-order design tool to support the design/evaluation of pulse jet mixers. The modeling begins with the Eulerian-Granular 2-phase flow equations governing the suspension, transport, and deposition of particulates in a carrier fluid. The equations are simplified based on observations from CFD pertinent to the zone-of-influence for the pulsed jet flow leading to a reduced set for which the s...
Design of open channels (launders), junction boxes, and distribution boxes for conveyance of slur... more Design of open channels (launders), junction boxes, and distribution boxes for conveyance of slurries in concentrator projects for mining and metals is typically accomplished by visiting existing mills, formulating a design using the successes and problems of previous work, and reviewing within the project design team. This is an expensive design process and may result in overly conservative designs and in performance problems caused by non-uniform flow distribution. This paper describes a methodology for simulating the fluid and solid flow dynamics of slurries based on computational fluid dynamic (CFD) modeling techniques. The CFD model presented here is based on a specific case study of a ball mill feed slurry distribution box, for which plant operating data and on-site observations were provided and used for comparison. The use of CFD is demonstrated on the upstream launder and several evolutions of the box design. Site observations and actual data are compared to the model predi...
23rd International Conference on Offshore Mechanics and Arctic Engineering, Volume 1, Parts A and B, 2004
The newly constructed Tacoma Narrows Bridge Piers represent large concrete floating caissons duri... more The newly constructed Tacoma Narrows Bridge Piers represent large concrete floating caissons during their construction. For designing their mooring system the current force applied on the caissons in the Narrows must be known. The flow field around the caisson is highly complex and the calculation of the current load on the caisson by analytical means is difficult. On the other hand, model tests suffer from the distortion in the Reynolds number. Therefore, a two-prong approach was undertaken. Besides the fixed model test of the caissons for current forces, a CFD analysis of the flow around the caisson is chosen. A 3-D CFD approach is considered more appropriate than a 2-D one, since the bottom contour at the site is irregular and water depth is rather shallow. This paper discusses the CFD method and the results obtained from such analysis. The numerical analysis was carried out in both ebb and flood flow of the tidal current in the basin. One of the difficulties of the computational...
Volume 4: Codes, Standards, Licensing, and Regulatory Issues; Fuel Cycle, Radioactive Waste Management and Decommissioning; Computational Fluid Dynamics (CFD) and Coupled Codes; Instrumentation and Co, 2012
ABSTRACT A method to decrease the modeling time for a computational fluid dynamics (CFD) simulati... more ABSTRACT A method to decrease the modeling time for a computational fluid dynamics (CFD) simulation of the pump-out process of a multi-constituent, radioactive slurry in a mixing vessel is developed. Although a true CFD simulation of transferring such slurry from a vessel is possible, the process requires the simulation of about a five- to ten-hour process (real-time). To reduce this time, a method is developed based on extracting information from CFD models at discrete stages during the vessel pump-down process. These discrete CFD models are used to feed a control-volume analysis. The result is the reduction in the computational time by eighty to ninety percent, while retaining the ability to compute the waste contents of each constituent through the pump-down process to high accuracy (< 4% error in mass transferred from a vessel). Current efforts are evaluating the coupling of CFD models with seven inhomogeneous phases. The overall result is a more efficient and effective CFD model that represents a true CFD simulation of a vessel pump down to high accuracy.
Journal of rehabilitation research and development, 1998
Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many diseases, ... more Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many diseases, such as stroke, multiple sclerosis, neuromuscular diseases, and cancer. Its complications include choking, aspiration, malnutrition, cachexia, and dehydration. The goal in dysphagia management is to provide adequate nutrition and hydration while minimizing the risk of choking and aspiration. It is important to advance the individual toward oral feeding in a timely manner to enhance the recovery of swallowing function and preserve the quality of life. Current clinical assessments of dysphagia are limited in providing adequate guidelines for oral feeding. Mathematical modeling of the fluid dynamics of pharyngeal bolus transport provides a unique opportunity for studying the physiology and pathophysiology of swallowing. Finite element analysis (FEA) is a special case of computational fluid dynamics (CFD). In CFD, the flow of a fluid in a space is modeled by covering the space with a grid an...
ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B, 2011
Transport and processing of nuclear waste for treatment and storage can involve unique and comple... more Transport and processing of nuclear waste for treatment and storage can involve unique and complex thermal and fluid dynamic conditions that pose potential for safety risk and/or design uncertainty and also are likely to be subjected to more precise performance requirements than in other industries. From an engineering analysis perspective, certainty of outcome is essential. Advanced robust methods for engineering analysis and simulation of critical processes can help reduce risk of design uncertainty and help mitigate or reduce the amount of expensive full-scale demonstration testing. This paper will discuss experience gained in applying computational fluid dynamics models to key processes for mixing, transporting, and thermal treatment of nuclear waste as part of designing a massive vitrification process plant that will convert high and low level nuclear waste into glass for permanent storage. Examples from industrial scale simulations will be presented. The computational models h...
Volume 4: Computational Fluid Dynamics, Neutronics Methods and Coupled Codes; Student Paper Competition, 2006
The Energy Citations Database (ECD) provides access to historical and current research (1948 to t... more The Energy Citations Database (ECD) provides access to historical and current research (1948 to the present) from the Department of Energy (DOE) and predecessor agencies.
Computational Technologies for Fluid/Thermal/Structural/Chemical Systems With Industrial Applications, Volume 2, 2002
ABSTRACT This paper presents the use of advanced computer simulation (coupled Computational Fluid... more ABSTRACT This paper presents the use of advanced computer simulation (coupled Computational Fluid Dynamics and process modeling) to determine the effects of burner change out in a steam-methane reformer (SMR). SMR’s are used to generate hydrogen for oil refinery operation and synthesis gas for chemical plant production. A stream of natural gas and steam reacts inside a large number of catalyst-filled tubes housed inside the SMR furnace. Burner replacement in the furnace can result in reduced hydrogen production, decreased efficiency, and unstable operation. To help select a suitable replacement burner and optimize furnace performance CFD modeling was used to identify the impact of different burners on the following key SMR design parameters: • Local heat flux profiles on the reformer tubes; • Local peak and average reformer tube skin temperatures; • Heat Flux in the pre-heat tubes; • SMR Hydrogen production and process conditions. With a replacement burner selected, the ‘coupled’ CFD model was then used to predict the burner-firing pattern that maximizes hydrogen production within the SMR design constraints.
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Papers by Brigette Rosendall, PhD