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The Rheology of Concentrated Suspensions

Description: Research program on the rheological properties of flowing suspensions. The primary purpose of the research supported by this grant was to study the flow characteristics of concentrated suspensions of non-colloidal solid particles and thereby construct a comprehensive and robust theoretical framework for modeling such systems quantitatively. At first glance, this seemed like a modest goal, not difficult to achieve, given that such suspensions were viewed simply as Newtonian fluids with an effective viscosity equal to the product of the viscosity of the suspending fluid times a function of the particle volume fraction. But thanks to the research findings of the Principal Investigator and of his Associates, made possible by the steady and continuous support which the PI received from the DOE Office of Basic Energy Sciences, the subject is now seen to be more complicated and therefore much more interesting in that concentrated suspensions have been shown to exhibit fascinating and unique rheological properties of their own that have no counterpart in flowing Newtonian or even non-Newtonian (polymeric) fluids. In fact, it is generally acknowledged that, as the result of these investigations for which the PI received the 2001 National Medal of Science, our understanding of how suspensions behave under flow is far more detailed and comprehensive than was the case even as recently as a decade ago. Thus, given that the flow of suspensions plays a crucial role in many diverse physical processes, our work has had a major and lasting impact in a subject having both fundamental as well as practical importance.
Date: September 7, 2004
Creator: Acrivos, Andreas
Partner: UNT Libraries Government Documents Department

Review Of Rheology Models For Hanford Waste Blending

Description: The area of rheological property prediction was identified as a technology need in the Hanford Tank Waste - waste feed acceptance initiative area during a series of technical meetings among the national laboratories, Department of Energy-Office of River Protection, and Hanford site contractors. Meacham et al. delivered a technical report in June 2012, RPP-RPT-51652 ''One System Evaluation of Waste Transferred to the Waste Treatment Plant'' that included estimating of single shell tank waste Bingham plastic rheological model constants along with a discussion of the issues inherent in predicting the rheological properties of blended wastes. This report was selected as the basis for moving forward during the technical meetings. The report does not provide an equation for predicting rheological properties of blended waste slurries. The attached technical report gives an independent review of the provided Hanford rheological data, Hanford rheological models for single tank wastes, and Hanford rheology after blending provided in the Meacham report. The attached report also compares Hanford to SRS waste rheology and discusses some SRS rheological model equations for single tank wastes, as well as discussing SRS experience with the blending of waste sludges with aqueous material, other waste sludges, and frit slurries. Some observations of note: Savannah River Site (SRS) waste samples from slurried tanks typically have yield stress >1 Pa at 10 wt.% undissolved solids (UDS), while core samples largely have little or no yield stress at 10 wt.% UDS. This could be due to how the waste has been processed, stored, retrieved, and sampled or simply in the differences in the speciation of the wastes. The equations described in Meacham's report are not recommended for extrapolation to wt.% UDS beyond the available data for several reasons; weak technical basis, insufficient data, and large data scatter. When limited data are available, for example two to ...
Date: September 26, 2013
Creator: Koopman, D. C. & Stone, M.
Partner: UNT Libraries Government Documents Department

Review Of Rheology Modifiers For Hanford Waste

Description: As part of Savannah River National Laboratory (SRNL)'s strategic development scope for the Department of Energy - Office of River Protection (DOE-ORP) Hanford Tank Waste Treatment and Immobilization Plant (WTP) waste feed acceptance and product qualification scope, the SRNL has been requested to recommend candidate rheology modifiers to be evaluated to adjust slurry properties in the Hanford Tank Farm. SRNL has performed extensive testing of rheology modifiers for use with Defense Waste Processing Facility (DWPF) simulated melter feed - a high undissolved solids (UDS) mixture of simulated Savannah River Site (SRS) Tank Farm sludge, nitric and formic acids, and glass frit. A much smaller set of evaluations with Hanford simulated waste have also been completed. This report summarizes past work and recommends modifiers for further evaluation with Hanford simulated wastes followed by verification with actual waste samples. Based on the review of available data, a few compounds/systems appear to hold the most promise. For all types of evaluated simulated wastes (caustic Handford tank waste and DWPF processing samples with pH ranging from slightly acidic to slightly caustic), polyacrylic acid had positive impacts on rheology. Citric acid also showed improvement in yield stress on a wide variety of samples. It is recommended that both polyacrylic acid and citric acid be further evaluated as rheology modifiers for Hanford waste. These materials are weak organic acids with the following potential issues: The acidic nature of the modifiers may impact waste pH, if added in very large doses. If pH is significantly reduced by the modifier addition, dissolution of UDS and increased corrosion of tanks, piping, pumps, and other process equipment could occur. Smaller shifts in pH could reduce aluminum solubility, which would be expected to increase the yield stress of the sludge. Therefore, it is expected that use of an acidic modifier would ...
Date: September 30, 2013
Creator: Pareizs, J. M.
Partner: UNT Libraries Government Documents Department

Morphological, rheological and electrochemical studies ofpoly(ethylene oxide) electrolytes containing fumed silicananoparticles

Description: In this paper, the rheology and crystallization of composite Poly(Ethylene Oxide) (PEO) electrolytes were studied by dynamic mechanical analysis, DSC and polarized light microscopy. The effects of fumed silica nanoparticles on the conductivities of the polymer electrolytes at temperatures above and below their melting point were measured and related to their rheology and crystallization behavior, respectively. The electrolyte/electrode interfacial properties and cycling performances of the composite polymer electrolytes in Li/Li cells are also discussed. The measured electrochemical properties were found to depend heavily on the operational environments and sample processing history.
Date: June 1, 2003
Creator: Xie, Jiangbing; Kerr, John B.; Duan, Robert G. & Han, Yongbong
Partner: UNT Libraries Government Documents Department

Preparation and Characterization of Injectable Brushite Filled-Poly (Methyl Methacrylate) Bone Cement

Description: This article discusses the design of an alternative cement system that can better accommodate calcium-phosphate additives while preserving cement rheological properties and performance.
Date: September 19, 2014
Creator: Rodriguez, Lucas C.; Chari, Jonathan; Aghyarian, Shant; Gindri, Izabelle M.; Kosmopoulos, Victor & Rodrigues, Danieli C.
Partner: UNT College of Engineering

Synthesis and rheological properties of cation-exchanged Laponite suspensions

Description: In this paper we report our new approach to synthesize cation-exchanged Laponite suspensions. General observations of the prepared samples indicated that an aqueous suspension of 1 wt% Laponite retained its free flowing liquid phase characteristics even after aging for several weeks. When bivalent cationic metals (Cu, Co, Ni) were ablated into the suspension, the strong charge of the crystal face was reduced and, on standing, the suspension gelled becoming highly viscous. This sol-gel transition was induced by the formation of a space-filled structure due to both van derWaals and electrostatic bonds between the positively charged rims and negatively charged faces. Rheological properties of such prepared suspensions were measured using a Brookfield DV-H Pro Viscometer with a small sample adapter{SSA18/13RPY). The yield strengths of2.2 N/m2, 3.2 N/m2, and 1.7 N/m2 were measured for Ni-, Co-, and Cu-modified Laponite suspensions, respectively. These yield strengths are sufficiently high for suspending weighting materials such as barite which requires the gel strength of about 0.5 N/m2.
Date: January 1, 2009
Creator: Tran, X.P.; Howard, B. & Chyu, M.K.
Partner: UNT Libraries Government Documents Department

Asymmetrical polarization of spherical colloidal particle double layer in electrical fields

Description: It has long been accepted that the drastic increase in the viscosity of electrorheological fluids subjected to electric fields is due to interactions between the induced dipole moments of the colloidal particles in the suspensions. Computer simulations of dipole-dipole interactions have produced chain and column formations of particles in the direction of the applied field that agree well with experimental observations. In an aqueous suspension of colloidal particles, however, the polarization of particles is very sensitive to the frequency of the applied electric field, and the dynamics of the particles can differ drastically from the dynamics that would be expected from a simple induced dipole model. In certain frequency regimes, instead of forming chains and columns in the direction of a linear applied field, the particles are dynamically unstable and circulate in bands that tilt at a significant angle relative to the direction of the field. This indicates that the interactions between the particles are no longer symmetrical with respect to the applied electric field. The authors have proposed a phenomenological model to explain the mechanism of this symmetry breaking. They have carried out a computer simulation of colloidal particle dynamics resulting from their model, and the results of the simulation agree well with experimental observations. When a particle is spinning, the diffusion of the ions in the double layer becomes asymmetrical with respect to the electric field, with the ions diffusing faster in the direction of spinning than against it. This causes the induced dipole moment of the particle to be misaligned with respect to the applied field. The authors earlier simulation results show that this misalignment between the polarization of the particle and the applied electric field plays a crucial role in the formation of a band of particles tilted at an angle relative to the direction of ...
Date: April 1, 1995
Creator: Hu, Y.; Kumar, V. & Fraden, S.
Partner: UNT Libraries Government Documents Department

Light scattering studies of an electrorheological fluid in oscillatory shear

Description: We have conducted a real time, two-dimensional light scattering study of the nonlinear dynamics of field-induced structures in an electrorheological fluid subjected to oscillatory shear. We have developed a kinetic chain model of the observed dynamics by considering the response of a fragmenting/aggregating particle chain to the prevailing hydrodynamic and electrostatic forces. This structural theory is then used to describe the nonlinear rheology of ER fluids.
Date: December 31, 1995
Creator: Martin, J.E. & Odinek, J.
Partner: UNT Libraries Government Documents Department

Development of a Laponite Pluronic Composite for Foaming Applications

Description: The focus of the following research was to provide an optimized particle stabilized foam of Laponite and Pluronic L62 in water by understanding (1) the Laponite-Pluronic interactions and properties for improved performance in a particle stabilized foam and (2) the interfacial properties between air and the Laponite-Pluronic complex. These studies were conducted using both bulk and interfacial rheology, XRD, sessile droplet, TGA and UV-vis. Two novel and simple techniques, lamella break point and capillary breakup extensional rheometry, were used to both understand the Laponite Pluronic L62 interaction and determine a different mechanism for foaming properties. Bulk rheological properties identified an optimal Laponite concentration of 2% with Pluronic L62 ranging from 2.5% and 6.5%, due to the ease of flow for the dispersion. The Pluronic L62 was observed to enhance the Laponite bulk rheological properties in solution. Additionally TGA showed a similar trend in thermal resistance to water with both addition of Laponite and Pluronic L62. XRD demonstrated that 0.25% Pluronic intercalated into Laponite from dried 2% Laponite films. XRD demonstrated that the Laponite matrix was saturated at 1% Pluronic L62. UV-vis demonstrated that a monolayer of Pluronic L62 is observed up to 0.65% Pluronic L62 onto Laponite. Interfacial rheology showed that Laponite enhances Pluronic L62 at the air-liquid interface by improving the storage modulus as low at 0.65% Pluronic L62 with 2% Laponite. The lamella breakpoint of Laponite with Pluronic films indicate strong film interaction due to higher increases in mass. Extensional rheology indicates that 2.5% to 6.5% Pluronic with 2% Laponite show the most filament resistance to stretching.
Date: December 2012
Creator: Davis, James William
Partner: UNT Libraries

Temperature dependent rheology of surfactant-hydroxypropyl cellulose solutions.

Description: The rheology of 1-8% hydroxypropyl cellulose (HPC) solutions has been studied in the temperature range of 20-45 degrees Celsius. The results showed that the relative viscosity at each HPC concentration decreases with increasing temperature. The relative viscosity decreases drastically at about 43 degrees Celsius due to a phase transition. The influence of anionic surfactant, sodium dodecylsulfate (SDS), induced gelation of a 2% HPC solution. The HPC solutions gelled at surfactant SDS concentrations ranging from 0.4 to 1.0 critical micelle concentration (CMC). The gelation of the HPC/SDS hydrogel is explained in the surfactant SDD - bridged HPC linear polymer chains. The complex viscosity - concentration profile was determined below the CMC of the SDS - water pair. The peak itself was a function of frequency indicating the presence of two relaxation times within the gelled network.
Date: December 2002
Creator: Snively, C. Todd
Partner: UNT Libraries

Responsive Copolymers for Enhanced Petroleum Recovery

Description: The objectives of this work was to: (1) synthesize responsive, amphiphilic systems; (2) characterize molecular structure and solution behavior; (3) measure rheological properties of the aqueous fluids including behavior in fixed geometry flow profiles and beds; and (4) to tailor polymer compositions for in situ rheology control under simulated reservoir conditions.
Date: February 27, 2002
Creator: McCormick, Charles & Hester, Roger
Partner: UNT Libraries Government Documents Department

Development of a model colloidal system for rheology simulation.

Description: The objective of the experimental effort is to provide a model particle system that will enable modeling of the macroscopic rheology from the interfacial and environmental structure of the particles and solvent or melt as functions of applied shear and volume fraction of the solid particles. This chapter describes the choice of the model particle system, methods for synthesis and characterization, and results from characterization of colloidal dispersion, particle film formation, and the shear and oscillatory rheology in the system. Surface characterization of the grafted PDMS interface, dispersion characterization of the colloids, and rheological characterization of the dispersions as a function of volume fraction were conducted.
Date: October 1, 2008
Creator: Schunk, Peter Randall; Tallant, David Robert; Piech, Martin (United Technologies Research Center, East Hartford, CT); Bell, Nelson Simmons & Frischknecht, Amalie Lucile
Partner: UNT Libraries Government Documents Department

Final Report DOE Award # DE-FG02-05ER46218, Texas Tech University: "Cyclic Macromolecules: Dynamics and Nonlinear Rheology"

Description: The work described in the present report had the original goal to produce large, entangled, ring polymers that were uncontaminated by linear chains and to characterize by rheological methods the dynamics of these rings. While the work fell short of this specific goal, the outcomes of the research performed under support from this grant provided novel macromolecular synthesis methods, new separation methods for ring and linear chains, and novel rheological data on bottle brush polymers, wedge polymers and dendron-based ring molecules. The grant funded a total of 8 archival manuscripts and one patent, all of which are attached to the present report.
Date: April 25, 2012
Creator: McKenna, Gregory B.; Grubbs, Robert H. & Kornfield, Julia A.
Partner: UNT Libraries Government Documents Department

A Summary of Rheology Data For SB3 and SB2/3 Blend Simulant Savannah River Site Wastes

Description: The purpose of this study was to document the rheological measurements made for Sludge Batch 3 (SB3) and the blend of SB3 with Sludge Batch 2 (SB2). These measurements were primarily made on Slurry Mix Evaporator (SME) products, i.e. melter feeds. Some measurements were made on SB2/3 blend Sludge Receipt and Adjustment Tank (SRAT) products. Measurements on radioactive SB3 and SB2/3 samples have been limited to sludge characterization. SB2/3 measurements studied the impact of changing the SRAT acid addition strategy on the SRAT and SME product rheology. SB2/3 measurements also studied the impact of changing the waste loading target (sludge oxides content in glass) of the SME product. SB3 measurements studied the impact of changes in the wash end point and acid addition strategy on the SME product (melter feed) rheology. A summary of the significant findings is given below: SB3 radioactive sludge and blended SB2/3 radioactive sludge were less viscous than SB2 radioactive sludge. SB2/3 b lend sludge is more viscous than SB3 sludge. SB3 simulant SME product rheology was strongly impacted by changing the noble metal concentrations to more closely match those of the qualification sample. This reduction in noble metals produced a lower pH product that was also considerably less viscous. Increased acid addition in the SB2/3 SRAT generally led to less viscous simulant SRAT products. This trend did not persist in the SME products. SME products became more viscous when increased acid was used in the SRAT cycle from 135 per cent up to 170 per cent of stoichiometry, then became less viscous as total acid was increased further to 185 per cent. A significant increase in hydrogen generation occurred between 170 per cent and 185 per cent. The impact of acid addition on SB3 SME products was also variable. The impact of waste loading changes ...
Date: March 1, 2004
Creator: KOOPMAN, DAVIDC.
Partner: UNT Libraries Government Documents Department

The effects of process parameters on injection-molded PZT ceramics part fabrication- compounding process rheology.

Description: Solid solutions of lead-based perovskites are the backbone materials of the piezoelectric components for transducer, actuator, and resonator applications. These components, typically small in size, are fabricated from large sintered ceramic slugs using grinding and lapping processes. These operations increase manufacturing costs and produce a large hazardous waste stream, especially when component size decreases. To reduce costs and hazardous wastes associated with the production of these components, an injection molding technique is being investigated to replace the machining processes. The first step in the new technique is to compound an organic carrier with a ceramic powder. The organic carrier is a thermoplastic based system composed of a main carrier, a binder, and a surfactant. Understanding the rheology of the compounded material is necessary to minimize the creation of defects such as voids or cavities during the injection-molding process. An experiment was performed to model the effects of changes in the composition and processing of the material on the rheological behavior. Factors studied included: the surfactant of the organic carrier system, the solid loading of the compounded material, and compounding time. The effects of these factors on the viscosity of the material were investigated.
Date: May 1, 2005
Creator: Halbleib, Laura L.; Yang, Pin; Mondy, Lisa Ann & Burns, George Robert
Partner: UNT Libraries Government Documents Department

Rheology and TIC/TOC results of ORNL tank samples

Description: The Savannah River National Laboratory (SRNL)) was requested by Oak Ridge National Laboratory (ORNL) to perform total inorganic carbon (TIC), total organic carbon (TOC), and rheological measurements for several Oak Ridge tank samples. As received slurry samples were diluted and submitted to SRNL-Analytical for TIC and TOC analyses. Settled solids yield stress (also known as settled shear strength) of the as received settled sludge samples were determined using the vane method and these measurements were obtained 24 hours after the samples were allowed to settled undisturbed. Rheological or flow properties (Bingham Plastic viscosity and Bingham Plastic yield stress) were determined from flow curves of the homogenized or well mixed samples. Other targeted total suspended solids (TSS) concentrations samples were also analyzed for flow properties and these samples were obtained by diluting the as-received sample with de-ionized (DI) water.
Date: April 26, 2013
Creator: Pareizs, J. M. & Hansen, E. K.
Partner: UNT Libraries Government Documents Department

FINAL REPORT DURAMELTER 100 HLW SIMULANT VALIDATION TESTS WITH C-106/AY-102 FEEDS VSL-05R5710-1 REV 0 6/2/05

Description: The principal objectives of the DM100 tests were to determine the processing characteristics of several C-106/AY102 feeds derived from simulants prepared by different methods, which result in different physical characteristics of the feed. The VSL simulant used in a previous test was prepared by the direct hydroxide method, which was the method used for feed preparation in the bulk of previous VSL melter testing. The NOAH Technologies Corporation modified-rheology simulant was prepared to the same composition as the VSL simulant using a method that resulted in rheological properties closer to those of certain actual waste samples. The SIPP simulant was produced by processing a co-precipitated waste simulant through a non-radioactive pilot scale semi-integrated pretreatment facility. The general intent of these tests was to provide a basis for determining whether the variations in rheology or other feed physical characteristics arising from the different methods of simulant preparation have significant effects on the processing characteristics of the feed in the melter. Completion of the test objectives is detailed in a table.
Date: December 29, 2011
Creator: AA, KRUGER; KS, MATLACK; W, GONG & IL, PEGG
Partner: UNT Libraries Government Documents Department

An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

Description: The Hanford Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify a large portion of the waste in Hanford’s 177 underground waste storage tanks. Numerous process vessels will hold waste at various stages in the WTP. Some of these vessels have mixing-system requirements to maintain conditions where the accumulation of hydrogen gas stays below acceptable limits, and the mixing within the vessels is sufficient to release hydrogen gas under normal conditions and during off-normal events. Some of the WTP process streams are slurries of solid particles suspended in Newtonian fluids that behave as non-Newtonian slurries, such as Bingham yield-stress fluids. When these slurries are contained in the process vessels, the particles can settle and become progressively more concentrated toward the bottom of the vessels, depending on the effectiveness of the mixing system. One limiting behavior is a settled layer beneath a particle-free liquid layer. The settled layer, or any region with sufficiently high solids concentration, will exhibit non-Newtonian rheology where it is possible for the settled slurry to behave as a soft solid with a yield stress. In this report, these slurries are described as settling cohesive slurries.
Date: May 22, 2009
Creator: Gauglitz, Phillip A.; Wells, Beric E.; Fort, James A. & Meyer, Perry A.
Partner: UNT Libraries Government Documents Department

SRAT CHEMISTRY AND ACID CONSUMPTION DURING SIMULATED DWPF MELTER FEED PREPARATION

Description: Due to higher than expected hydrogen generation during the Tank 51-Sludge Batch 4 (SB4) qualification run, DWPF engineering requested the Savannah River National Laboratory (SRNL) to expand the ongoing catalytic hydrogen generation program. The work presented in this Technical Report was identified as part of SRNL/Liquid Waste Organization (LWO) meetings to define potential causes of catalytic hydrogen generation as well as from an external technical review panel commissioned to evaluate SRNL hydrogen related data and programs. New scope included improving the understanding of SRAT/SME process chemistry, particularly as it related to acid consumption and hydrogen generation. The expanded hydrogen program scope was covered under the technical task request (TTR): HLW-DWPF-TTR-2007-0016. A task technical and quality assurance plan (TT&QAP) was issued to cover focus areas raised in meetings with LWO plus a portion of the recommendations made by the review panel. A supporting analytical study plan was issued. It was also noted in the review of catalytic hydrogen generation that control of the DWPF acid stoichiometry was an important element in controlling hydrogen generation. A separate TTR was issued to investigate ways of improving the determination of the acid requirement during processing: HLWDWPF-TTR-0015. A separate TT&QAP was prepared for this task request. This report discusses some progress on this task related to developing alternative acid equations and to performing experimental work to supplement the existing database. Simulant preparation and preliminary flowsheet studies were already documented. The prior work produced a sufficient quantity of simulant for the hydrogen program and melter feed rheology testing. It also defined a suitable acid addition stoichiometry. The results presented in this report come from samples and process data obtained during sixteen 22-L SRAT/SME simulations that were performed in the second half of 2007 to produce eight SME products with frit 418 and a matching set of ...
Date: December 3, 2008
Creator: Koopman, D; David Best, D & Bradley Pickenheim, B
Partner: UNT Libraries Government Documents Department

Rheological Behavior of Dense Assemblies of Granular Materials

Description: Assemblies of granular materials behave differently when they are owing rapidly, from when they are slowly deforming. The behavior of rapidly owing granular materials, where the particle-particle interactions occur largely through binary collisions, is commonly related to the properties of the constituent particles through the kinetic theory of granular materials. The same cannot be said for slowly moving or static assemblies of granular materials, where enduring contacts between particles are prevalent. For instance, a continuum description of the yield characteristics of dense assemblies of particles in the quasistatic ow regime cannot be written explicitly on the basis of particle properties, even for cohesionless particles. Continuum models for this regime have been proposed and applied, but these models typically assume that the assembly is at incipient yield and they are expressed in terms of the yield function, which we do not yet know how to express in terms of particle-level properties. The description of the continuum rheology in the intermediate regime is even less understood. Yet, many practically important flows in nature and in a wide range of technological applications occur in the dense flow regime and at the transition between dilute and dense regimes; the lack of validated continuum rheological models for particle assemblies in these regimes limits predictive modeling of such flows. This research project is aimed at developing such rheological models.
Date: March 31, 2011
Creator: Sundaresan, Sankaran; Tardos, Gabriel I & Subramaniam, Shankar
Partner: UNT Libraries Government Documents Department

Rheology Modifiers for Radioactive Waste Slurries

Description: The goals of this study were to determine if trace levels of chemical additives could be used to reduce the rheological characteristics of radioactive waste slurries, identify potential chemical additives for this work and future testing, test a limited set of chemical additive candidates on simulated radioactive wastes, and develop advanced techniques to visualize the internal slurry structure and particle-particle interaction within the slurry.
Date: February 19, 2003
Creator: Calloway, T.B. Jr.
Partner: UNT Libraries Government Documents Department

Microstructure Development and Characteristics of Semisolid Aluminum Alloys

Description: A drop forge viscometer was employed to investigate the flow behavior under very rapid compression rates of A357, A356 diluted with pure aluminum and Al-4.5%Cu alloys. The A357 alloys were of commercial origin (MHD and SIMA) and the rheocast, modified A356 and Al-4.5Cu alloys were produced by a process developed at the solidification laboratory of MIT.
Date: May 15, 2001
Creator: Flemings, Merton & Viswanathan, srinath
Partner: UNT Libraries Government Documents Department

Development of phenomenological model for coal slurry atomization. Quarterly technical progress report

Description: Atomization tests on simulated fluids are being performed. For each sample tested, {Delta}P{sub c} is being determined as described in the last quarterly report. The results will be reported when the coal slurry testing is completed for comparative purposes. The viscoelastic properties on the simulated fluids and coal water slurries are being determined using the Adelphi Stresstech Viscometer. A discussion of viscoelastic properties and their relationship to atomization is presented.
Date: October 1, 1996
Creator: Dooher, J.
Partner: UNT Libraries Government Documents Department

In situ determination of rheological properties and void fraction: Hanford Waste Tank 241-SY-103

Description: This report presents the results of the operation of the void fraction instrument (VFI) and ball rheometer in Hanford Tank 241-SY-103. The two instruments were deployed through risers 17C and 22A in July and August 1995 to gather data on the gas content and rheology of the waste. The results indicate that the nonconvective sludge layer contains up to 12% void and an apparent viscosity of 104 to 105 cP with a yield strength less than 210 Pa. The convective layer measured zero void and had no measurable yield strength. Its average viscosity was about 45 cP, and the density was less than 1.5 g/cc. The average void fraction was 0.047 {plus_minus} 0.015 at riser 17C and 0.091 {plus_minus} 0.015 at riser 22A. The stored gas volume based on these void fraction measurements is 213 {plus_minus} 42 M{sup 3} at 1 atmosphere.
Date: November 1, 1995
Creator: Shepard, C.L.; Stewart, C.W.; Alzheimer, J.M.; Terrones, G.; Chen, G. & Wilkins, N.E.
Partner: UNT Libraries Government Documents Department