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Development of enhanced heat transfer/transport/storage slurries for thermal-system improvement

Description: This paper presents a formulation of a new concept for improving thermal-system performance by utilizing the combined mechanisms of enhanced heat transfer, transport, and thermal-energy storage associated with a phase-change slurry as the working fluid.
Date: January 1, 1983
Creator: Kasza, K.E. & Chen, M.M.
Partner: UNT Libraries Government Documents Department

Periodic large-amplitude thermal oscillations occurring in a buoyant plume

Description: Reactor events such as N-1 loop operation in conjunction with a leaky check valve in the down loop can cause flow to be convected back into the reactor outlet nozzle/piping region and to be back-flushed into the reactor outlet plenum. The preceding results in a temperature difference between pipe inflow and plenum. This temperature difference causes buoyancy forces which if large enough can cause: a pipe backflow and recirculation loop; and a thermal plume in the plenum. Both phenomena are being studied because they can produce undesirable pipe, nozzle and plenum wall thermal distributions, and hence undesirable thermal stresses. This paper discusses some features of the plume.
Date: January 1, 1983
Creator: Oras, J.J. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Persistance of horizontal-pipe thermal-transient-induced flow stratification

Description: In this paper focus is on Phase III simulated pipe stratification persistence resulting from a thermal transient passing through a horizontal pipe of the reactor system. Results presented here involve only the upstream leg of the two-pipe, horizontal elbow system used in the Phase III studies. Note that the orientation of the elbow at the end of a horizontal pipe (up, down, or in the horizontal plane) has an influence on the pipe stratification persistence time, t/sub p/. This matter is currently under investigation. For the purposes of this paper, only the horizontally disposed elbow data have been considered.
Date: January 1, 1983
Creator: Kuzay, T.M. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Resolution of thermal striping issue downstream of a horizontal pipe elbow in stratified pipe flow. [LMFBR]

Description: A thermally stratified pipe flow produced by a thermal transient when passing through a horizontal elbow as a result of secondary flow gives rise to large thermal fluctuations on the inner curvature wall of the downstream piping. These fluctuations were measured in a specially instrumented horizontal pipe and elbow system on a test set-up using water in the Mixing Components Technology Facility (MCTF) at Argonne National Laboratory (ANL). This study is part of a larger program which is studying the influence of thermal buoyancy on general reactor component performance. This paper discusses the influence of pipe flow generated thermal oscillations on the thermal stresses induced in the pipe walls. The instrumentation was concentrated around the exit plane of the 90/sup 0/ sweep elbow, since prior tests had indicated that the largest thermal fluctuations would occur within about one hydraulic diameter downstream of the elbow exit. The thermocouples were located along the inner curvature of the piping and measured the near surface fluid temperature. The test matrix involved thermal downramps under turbulent flow conditions.
Date: January 1, 1985
Creator: Kuzay, T.M. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Assessment of impact of advanced energy transmission fluids on district heating and cooling systems (Phase 1)

Description: Argonne National Laboratory (ANL), under sponsorship of the US Department of Energy (DOE) Office of Buildings and Community Systems, has embarked upon a comprehensive, long-range program to develop high-performance advanced energy transmission fluids for use in district heating and cooling (DHC) systems. ANL has the lead technical role in this DOE program. These advanced fluids will substantially reduce flow frictional losses and enhance energy transfer. In system enhancement scoping studies conducted by ANL, the fluids yielded potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs. This report presents the first-phase results of assessment of impact of the advanced fluids on DHC systems. Future reports will focus on assessment of impact on hardware performance, capital eqiupment, and operation costs. 9 refs., 30 figs., 2 tab.
Date: September 1, 1987
Creator: Kasza, K.E. & Chen, M.M.
Partner: UNT Libraries Government Documents Department

Influence of thermal buoyancy on vertical tube bundle thermal density head predictions under transient conditions. [LMFBR]

Description: The thermal-hydraulic behavior of an LMFBR system under various types of plant transients is usually studied using one-dimensional (1-D) flow and energy transport models of the system components. Many of the transient events involve the change from a high to a low flow with an accompanying change in temperature of the fluid passing through the components which can be conductive to significant thermal bouyancy forces. Thermal bouyancy can exert its influence on system dynamic energy transport predictions through alterations of flow and thermal distributions which in turn can influence decay heat removal, system-response time constants, heat transport between primary and secondary systems, and thermal energy rejection at the reactor heat sink, i.e., the steam generator. In this paper the results from a comparison of a 1-D model prediction and experimental data for vertical tube bundle overall thermal density head and outlet temperature under transient conditions causing varying degrees of thermal bouyancy are presented. These comparisons are being used to generate insight into how, when, and to what degree thermal buoyancy can cause departures from 1-D model predictions.
Date: January 1, 1984
Creator: Lin, H.C. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Laser/fluorescent dye flow visualization technique developed for system component thermal hydraulic studies

Description: A novel laser flow visualization technique is presented together with examples of its use in visualizing complex flow patterns and plans for its further development. This technique has been successfully used to study (1) the flow in a horizontal pipe subject to temperature transients, to view the formation and breakup of thermally stratified flow and to determine instantaneous velocity distributions in the same flow at various axial locations; (2) the discharge of a stratified pipe flow into a plenum exhibiting a periodic vortex pattern; and (3) the thermal-buoyancy-induced flow channeling on the shell side of a heat exchanger with glass tubes and shell. This application of the technique to heat exchangers is unique. The flow patterns deep within a large tube bundle can be studied under steady or transient conditions. This laser flow visualization technique constitutes a very powerful tool for studying single or multiphase flows in complex thermal system components.
Date: January 1, 1988
Creator: Oras, J.J. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Thermal laminarization of a stratified pipe flow

Description: The present work constitutes a new program that grew out of a scoping assessment by ANL to determine the propensity for pipe stratification to occur in the reactor outlet nozzles and hot-leg piping of a generic LMFBR during events producing reverse pipe flow. This paper focuses on the role that thermal buoyancy plays relative to being able to laminarize a turbulent stratified shear zone in a horizontal pipe. The preceeding can influence the behavior of a pipe stratified-backflow-recirculation zone (cold plenum water down into the hot pipe flow) which developes as the result of a temperature difference between the pipe flow and the plenum.
Date: January 1, 1984
Creator: Oras, J.J. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Thermal oscillations downstream of an elbow in stratified pipe flow

Description: In previously published papers, the test geometry, test methodology and the scope of the thermal transient induced pipe stratification studies at Argonne National Laboratory (ANL) were explained. In these prior studies, limited fluid temperature data from elbow inlet and exit plane thermocouples indicated the presence of large-amplitude thermal fluctuations for conditions in which the horizontal pipe upstream of the elbow developed stratified flow induced by a pipe entrant thermal transient. Under severe transient conditions, thermal oscillations of amplitude of almost 70 percent of the pipe inlet transient temperature change were observed in the bulk flow. TC data and accompanying flow visualization test results showed that the largest near wall thermal oscillations were located within and immediately downstream of the elbow. The thermal oscillations if they are of large enough amplitude, of the appropriate frequency, and of sufficiently long duration can cause thermal stripping and thermal-fatigue stress cracking in the elbow region. A specially instrumented test section was fabricated to study these thermal fluctuations.
Date: January 1, 1984
Creator: Kuzay, T.M. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Thermal striping downstream of a horizontal elbow under thermally stratified transient flow conditions

Description: A thermally stratified flow produced by a thermal transient passing through a horizontal elbow gives rise to large thermal fluctuations on the inner curvature wall of the downstream piping. These fluctuations were measured in a specially instrumented horizontal pipe and elbow system on a test set-up using water in the Mixing Components Technology Facility. This study is part of a larger program which is studying the influence of thermal buoyancy on general reactor component performance. This paper discusses the influence of pipe flow generated thermal oscillations on the structured thermal stresses induced in the pipe walls.
Date: June 1, 1984
Creator: Kuzay, T.M. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Use of laser flow visualization techniques in reactor component thermal-hydraulic studies

Description: To properly design reactor components, an understanding of the various thermal hydraulic phenomena, i.e., thermal stratification flow channeling, recirculation regions, shear layers, etc., is necessary. In the liquid metal breeder reactor program, water is commonly used to replace sodium in experimental testing to facilitate the investigations, (i.e., reduce cost and allow fluid velocity measurement or flow pattern study). After water testing, limited sodium tests can be conducted to validate the extrapolation of the water results to sodium. This paper describes a novel laser flow visualization technique being utilized at ANL together with various examples of its use and plans for further development. A 3-watt argon-ion laser, in conjunction with a cylindrical opticallens, has been used to create a thin (approx. 1-mm) intense plane of laser light for the illuminiation of various flow tracers in precisely defined regions of interest within a test article having windows. Both fluorescing dyes tuned to the wavelength of the laser light (to maximize brightness and sharpness of flow image) and small (< 0.038-mm, 0.0015-in. dia.) opaque, nearly neutrally buoyant polystyrene spheres (to ensure that the particles trace out the fluid motion) have been used as flow tracers.
Date: January 1, 1984
Creator: Oras, J.J. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Mitigation of thermal transients by tube bundle inlet plenum design. [LMFBR]

Description: A multiphase program aimed at investigating the importance of thermal buoyancy to LMFBR steam-generator and heat-exchanger thermal hydraulics under low-flow transient conditions is being conducted in the Argonne Mixing Components Test Facility (MCTF) on a 60/sup 0/ sector shell-side flow model of the Westinghouse straight-tube steam generator being developed under the US/DOE large-component development program. A series of shell-side constant-flow thermal-downramp transient tests have been conducted focusing on the phenomenon of thermal-buoyancy-induced-flow channeling. In addition, it was discovered that a shell-inlet flow-distribution plenum can play a significant role in mitigating the severity of a thermal transient entering a steam generator or heat exchanger.
Date: June 1, 1984
Creator: Oras, J.J. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Overview of thermal-buoyancy-induced phenomena in reactor-plant components. [LMFBR]

Description: Studies related to delineating the influence of thermal-buoyancy forces on the thermal-hydraulics of Liquid Metal Fast Breeder Reactor plant components under low-flow thermal transient and steady state conditions have generated unique information which will aid design of these components. Various buoyancy force induced phenomena such as thermal stratification, flow recirculation, stagnation, and channeling are described and the importance to component performance are discussed. The water based studies have been conducted in the Mixing Components Test Facility, a large multi program facility capable of performing generic studies of fluid flow and heat transfer in reactor components under programmed transient and steady state conditions.
Date: January 1, 1984
Creator: Kasza, K.E.; Kuzay, T.M. & Oras, J.J.
Partner: UNT Libraries Government Documents Department

Measurement of velocity profiles in a stratified pipe flow recirculatory shear zone using laser flow visualization

Description: Argonne National Laboratory is studying pipe-flow/plenum thermal-plume interactions induced by a pipe-to-plenum temperature difference. Under these conditions a pipe-flow-generated thermal plume is produced in the plenum and a stratified recirculation zone is produced in the pipe resulting in cold fluid being drawn out of the plenum into the bottom of the horizontal pipe conveying hot fluid into the plenum. These phenomena produce plenum wall and pipe nozzle thermal distributions conductive to detrimental structural thermal stresses. In order to study these phenomena studies are being conducted in the ANL Buoyancy Effects Tank (BET), a 3.41-m/sup 3/ plenum containing cold water which is interfaced with a horizontal transparent pipe conveying hot water into the plenum.
Date: December 1, 1984
Creator: Kasza, K.E.; Oras, J.J. & Kolman, R.
Partner: UNT Libraries Government Documents Department

Thermal-hydraulic posttest analysis for the ANL/MCTF 360/sup 0/ model heat-exchanger water test under mixed convection. [LMFBR]

Description: As a result of the uncertainties in the understanding of the influence of thermal-buoyancy effects on the flow and heat transfer in Liquid Metal Fast Breeder Reactor heat exchangers and steam generators under off-normal operating conditions, an extensive experimental program is being conducted at Argonne National Laboratory to eliminate these uncertainties. Concurrently, a parallel analytical effort is also being pursued to develop a three-dimensional transient computer code (COMMIX-IHX) to study and predict heat exchanger performance under mixed, forced, and free convection conditions. This paper presents computational results from a heat exchanger simulation and compares them with the results from a test case exhibiting strong thermal buoyancy effects. Favorable agreement between experiment and code prediction is obtained.
Date: January 1, 1982
Creator: Yang, C.I.; Sha, W.T. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Overview of the ANL advanced LMR system thermal-hydraulic test program supporting both GE/PRISM and RI/SAFR

Description: Descriptions of the ANL thermal-hydraulic water models of both the PRISM and SAFR reactors are presented, together with results from Phases I and II of the thermal-hydraulic test program. Phenomena discovered during these tests and modeling results are presented. Overall, these efforts demonstrate the acceptable thermal-hydraulic performance of both the PRISM and SAFR concepts.
Date: January 1, 1988
Creator: Oras, J.J.; Kuzay, T.M. & Kasza, K.E.
Partner: UNT Libraries Government Documents Department

Ice slurry cooling development and field testing

Description: A new advanced cooling technology collaborative program is underway involving Argonne National Laboratory (ANL), Northern States Power (NSP) and the Electric Power Research Institute (EPRI). The program will conduct field tests of an ice slurry distributed load network cooling concept at a Northern States Power utility service center to further develop and prove the technology and to facilitate technology transfer to the private sector. The program will further develop at Argonne National Laboratory through laboratory research key components of hardware needed in the field testing and develop an engineering data base needed to support the implementation of the technology. This program will sharply focus and culminate research and development funded by both the US Department of Energy and the Electric Power Research Institute on advanced cooling and load management technology over the last several years.
Date: July 1, 1992
Creator: Kasza, K. E.; Hietala, J.; Wendland, R. D. & Collins, F.
Partner: UNT Libraries Government Documents Department

Nuclear power plant Generic Aging Lessons Learned (GALL). Appendix B

Description: The purpose of this generic aging lessons learned (GALL) review is to provide a systematic review of plant aging information in order to assess materials and component aging issues related to continued operation and license renewal of operating reactors. Literature on mechanical, structural, and thermal-hydraulic components and systems reviewed consisted of 97 Nuclear Plant Aging Research (NPAR) reports, 23 NRC Generic Letters, 154 Information Notices, 29 Licensee Event Reports (LERs), 4 Bulletins, and 9 Nuclear Management and Resources Council Industry Reports (NUMARC IRs) and literature on electrical components and systems reviewed consisted of 66 NPAR reports, 8 NRC Generic Letters, 111 Information Notices, 53 LERs, 1 Bulletin, and 1 NUMARC IR. More than 550 documents were reviewed. The results of these reviews were systematized using a standardized GALL tabular format and standardized definitions of aging-related degradation mechanisms and effects. The tables are included in volume s 1 and 2 of this report. A computerized data base has also been developed for all review tables and can be used to expedite the search for desired information on structures, components, and relevant aging effects. A survey of the GALL tables reveals that all ongoing significant component aging issues are currently being addressed by the regulatory process. However, the aging of what are termed passive components has been highlighted for continued scrutiny. This report consists of Volume 2, which consists of the GALL literature review tables for the NUMARC Industry Reports reviewed for the report.
Date: December 1996
Creator: Kasza, K. E.; Diercks, D. R.; Holland, J. W. & Choi, S. U.
Partner: UNT Libraries Government Documents Department

Microscale flow visualization of nucleate boiling in small channels: Mechanisms influencing heat transfer

Description: This paper describes the use of a new test apparatus employing flow visualization via ultra-high-speed video and microscope optics to study microscale nucleate boiling in a small, rectangular, heated channel. The results presented are for water. Because of confinement effects produced by the channel cross section being of the same nominal size as the individual vapor bubbles nucleating at discrete wall sites, flow regimes and heat transfer mechanisms that occur in small channels are shown to be considerably different than those in large channels. Flow visualization data are presented depicting discrete bubble/bubble and bubble/wall interactions for moderate and high heat flux. Quantitative data are also presented on nucleate bubble growth behavior for a single nucleation site in the form of growth rates, bubble sizes, and frequency of generation in the presence and absence of a thin wall liquid layer. Mechanistic boiling behavior and trends are observed which support the use of this type of research as a powerful means to gain fundamental insights into why, under some conditions, nucleate boiling heat transfer coefficients are considerably larger in small channels than in large channels.
Date: July 1, 1997
Creator: Kasza, K.E.; Didascalou, T. & Wambsganss, M.W.
Partner: UNT Libraries Government Documents Department

Steam generator tube integrity program: Annual report, August 1995--September 1996. Volume 2

Description: This report summarizes work performed by Argonne National Laboratory on the Steam Generator Tube Integrity Program from the inception of the program in August 1995 through September 1996. The program is divided into five tasks: (1) assessment of inspection reliability, (2) research on ISI (inservice-inspection) technology, (3) research on degradation modes and integrity, (4) tube removals from steam generators, and (5) program management. Under Task 1, progress is reported on the preparation of facilities and evaluation of nondestructive evaluation techniques for inspecting a mock-up steam generator for round-robin testing, the development of better ways to correlate failure pressure and leak rate with eddy current (EC) signals, the inspection of sleeved tubes, workshop and training activities, and the evaluation of emerging NDE technology. Results are reported in Task 2 on closed-form solutions and finite-element electromagnetic modeling of EC probe responses for various probe designs and flaw characteristics. In Task 3, facilities are being designed and built for the production of cracked tubes under aggressive and near-prototypical conditions and for the testing of flawed and unflawed tubes under normal operating, accident, and severe-accident conditions. Crack behavior and stability are also being modeled to provide guidance for test facility design, develop an improved understanding of the expected rupture behavior of tubes with circumferential cracks, and predict the behavior of flawed and unflawed tubes under severe accident conditions. Task 4 is concerned with the acquisition of tubes and tube sections from retired steam generators for use in the other research tasks. Progress on the acquisition of tubes from the Salem and McGuire 1 nuclear plants is reported.
Date: February 1998
Creator: Diercks, D. R.; Bakhtiari, S.; Kasza, K. E.; Kupperman, D. S.; Majumdar, S.; Park, J. Y. et al.
Partner: UNT Libraries Government Documents Department

Environmentally assisted cracking in light water reactors

Description: Cracking in sensitized austenitic stainless steel (SS) piping and associated components in boiling water reactors (BWRs) has been observed since the mid-1960s. Proposed remedies include procedures that produce a favorable residual stress state in the weld regions, replacement of the piping with materials that are more resistant to SCC, and modification of the reactor coolant environment. During this year, studies that have important implications for all three classes of proposed remedies have been carried out. These studies include fracture-mechanics crack-growth-rate tests on Type 316 NG SS and weld overlay specimens in impurity and high-purity environments, finite-element studies on weldments treated by the Mechanical Stress Improvement Process (MSIP) developed by O'Donnell and Associates, heat-to-heat studies of SCC in alternate alloys such as Types 316 NG and 347 Mod SS, and slow-strain-rate tests for the characterization of a variety of potential reactor coolant impurities. In addition, studies on the corrosion potential of irradiated stainless steel have been performed. This work is intended to provide a better understanding of the conditions associated with irradiation-assisted SCC (IASCC) in the core region.
Date: August 1, 1987
Creator: Shack, W.J.; Kassner, T.F.; Maiya, P.S.; Park, J.Y.; Ruther, W.E.; Kuczay, T.M. et al.
Partner: UNT Libraries Government Documents Department

Magnetically responsive microparticles for targeted drug and radionuclide delivery.

Description: We are currently investigating the use of magnetic particles--polymeric-based spheres containing dispersed magnetic nanocrystalline phases--for the precise delivery of drugs via the human vasculature. According to this review, meticulously prepared magnetic drug targeting holds promise as a safe and effective method of delivering drugs to specific organ, tissue or cellular targets. We have critically examined the wide range of approaches in the design and implementation of magnetic-particle-based drug delivery systems to date, including magnetic particle preparation, drug encapsulation, biostability, biocompatibility, toxicity, magnetic field designs, and clinical trials. However, we strongly believe that there are several limitations with past developments that need to be addressed to enable significant strides in the field. First, particle size has to be carefully chosen. Micrometer-sized magnetic particles are better attracted over a distance than nanometer sized magnetic particles by a constant magnetic field gradient, and particle sizes up to 1 {micro}m show a much better accumulation with no apparent side effects in small animal models, since the smallest blood vessels have an inner diameter of 5-7 {micro}m. Nanometer-sized particles &lt;70 nm will accumulate in organ fenestrations despite an effective surface stabilizer. To be suitable for future human applications, our experimental approach synthesizes the magnetic drug carrier according to specific predefined outcome metrics: monodisperse population in a size range of 100 nm to 1.0 {micro}m, non-toxic, with appropriate magnetic properties, and demonstrating successful in vitro and in vivo tests. Another important variable offering possible improvement is surface polarity, which is expected to prolong particle half-life in circulation and modify biodistribution and stability of drugs in the body. The molecules in the blood that are responsible for enhancing the uptake of particles by the reticuloendothelial system (RES) prefer to associate with hydrophobic surfaces. Accordingly, we will tackle this challenge by modifying the particles with hydrophilic coatings such ...
Date: February 16, 2004
Creator: Kaminski, M. D.; Ghebremeskel, A. N.; Nunez, L.; Kasza, K. E.; Chang, F.; Chien, T.-H. et al.
Partner: UNT Libraries Government Documents Department