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The Void Specification

Description: The purpose of this memo is to explore more fully the allowable void specification, in part to make it clearer to those doing the day-to-day evaluation and in part to help me understand the ramifications. A simulation of voids in a Be shell is used to support my understanding of Haan's analysis. The key results showing allowable void diameter as a function of void fraction are shown in Figure 6 (p. 8). What is important here is that generally in ''good'' samples we only see small voids, perhaps at most a few tenths of a {micro}m in size. For this void size the shells can be underdense by as much as 10% and still meet the 1 part in 10{sup 4} spec (though there may be other issues with reduced density).
Date: April 23, 2005
Creator: Cook, B
Partner: UNT Libraries Government Documents Department

Effect of Pressure with Wall Heating in Annular Two-Phase Flow

Description: The local distributions of void fraction, interfacial frequency and velocity have been measured in annular flow of R-134a through a wall-heated, high aspect ratio duct. High aspect ratio ducts provide superior optical access to tubes or irregular geometries. This work expands upon earlier experiments conducted with adiabatic flows in the same test section. Use of thin, transparent heater films on quartz windows provided sufficient electrical power capacity to produce the full range of two-phase conditions of interest. With wall vapor generation, the system pressure was varied from 0.9 to 2.4 MPa, thus allowing the investigation of flows with liquid-to-vapor density ratios covering the range of about 7 to 27, far less than studied in air-water and similar systems. There is evidence that for a given cross-sectional average void fraction, the local phase distributions can be different depending on whether the vapor phase is generated at the wall, or upstream of the test section inlet. In wall-heated flows, local void fraction profiles measured across both the wide and narrow test section dimensions illustrate the profound effect that pressure has on the local flow structure; notably, increasing pressure appears to thin the wall-bounded liquid films and redistribute liquid toward the edges of the test section. This general trend is also manifested in the distributions of mean droplet diameter and interfacial area density, which are inferred from local measurements of void fraction, droplet frequency and velocity. At high pressure, the interfacial area density is increased due to the significant enhancement in droplet concentration.
Date: October 31, 2000
Creator: Kumar, R. & Trabold, T.A.
Partner: UNT Libraries Government Documents Department

Experimental Investigation of Relative Permeability Upscaling from the Micro-Scale to the Macro-Scale

Description: During this reporting period, shown experimentally that the optical coherence imaging system can acquire information on grain interfaces and void shape for a maximum depth of half a millimeter into sandstone. The measurement of interfacial area per volume (IAV), capillary pressure and saturation in two dimensional micro-models structures has shown the existence of a unique relationship among these hydraulic parameters for different pore geometry. The measurement of interfacial area per volume on a three-dimensional natural sample, i.e., sandstone, has shown the homogeneity of IAV with depth in a sample when the fluids are in equilibrium.
Date: January 29, 2003
Creator: Pyrak-Nolte, Laura J.; Cheng, JiangTao; Yu, Ping; Giordano, Nicholas; Mustata, Mirela; Chen, Diaquam et al.
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

In situ rheology and gas volume in Hanford double-shell waste tanks

Description: This report is a detailed characterization of gas retention and release in 6 Hanford DS waste tanks. The results came from the ball rheometer and void fraction instrument in (flammable gas watch list) tanks SY-101, SY-103, AW-101, AN-103, AN-104, and AN-105 are presented. Instrument operation and derivation of data reduction methods are presented. Gas retention and release information is summarized for each tank and includes tank fill history and instrumentation, waste configuration, gas release, void fraction distribution, gas volumes, rheology, and photographs of the waste column from extruded core samples. Potential peak burn pressure is computed as a function of gas release fraction to portray the `hazard signature` of each tank. It is shown that two tanks remain well below the maximum allowable pressure, even if the entire gas content were released and ignited, and that none of the others present a hazard with their present gas release behavior.
Date: September 1, 1996
Creator: Stewart, C.W.; Alzheimer, J.M.; Brewster, M.E.; Chen, G.; Reid, H.C.; Shepard, C.L. et al.
Partner: UNT Libraries Government Documents Department

Comparison of Residual Saturation and Capillary Pressure Model with UNSODA Data

Description: The capillary pressure model correlates drainage and imbibition data from the UNSODA database, provided that the data incorporate the entry head, a minimum displacement required for drainage to begin. According to the model, the imbibition pressure equals the drainage pressures at a critical minimum saturation of 0.301; below this critical saturation, no additional reversible drainage should occur. Some of the UNSODA data sets had a minimum saturation approximately half this value. The difference is attributed to the presence of fissures, which would lower the residual wetting and critical minimum saturations by reducing the fraction of the void volume controlled by capillary pores. If the UNSODA saturations are adjusted for this discrepancy, a probability distribution of minimum saturations for each data set peaks near the predicted critical minimum saturation. Maximum saturations for each data set have a peak near the predicted residual nonwetting saturation of 0.884.
Date: April 1, 2004
Creator: LAURINAT, JAMESE.
Partner: UNT Libraries Government Documents Department

Data Observations on Double Shell Tank (DST) Flammable Gas Watch List Tank Behavior

Description: This report provides the data from the retained gas sampler, void fraction instrument, ball rheometer, standard hydrogen monitoring system, and other tank data pertinent to gas retention and release behavior in the waste stored in double-shelled Flammable Gas Watch List tanks at Hanford. These include tanks 241-AN-103,241-AN-104, 241-AN-105, 241-AW-101, 241-SY-101, and 241-SY-103. The tanks and the waste they contain are described in terms of fill history and chemistry. The results of mixer pump operation and recent waste transfers and back-dilution in SY-101 are also described. In-situ measurement and monitoring systems are described and the data are summarized under the categories of thermal behavior, waste configuration and properties, gas generation and composition, gas retention and historical gas release behavior.
Date: September 28, 2000
Creator: HEDENGREN, D.C.
Partner: UNT Libraries Government Documents Department

Development of the Butt Joint for the ITER Central Solenoid

Description: The ITER Central Solenoid (CS) requires compact and reliable joints for its Cable-in-Conduit Conductor (CICC). The baseline design is a diffusion bonded butt joint. In such a joint the mating cables are compacted to a very low void fraction in a copper sleeve and then heat treated. After the heat treatment the ends are cut, polished and aligned against each other and then diffusion bonded under high compression in a vacuum chamber at 750 C. The jacket is then welded on the conductor to complete the joint, which remarkably does not require more room than a regular conductor. This joint design is based on a proven concept developed for the ITER CS Model Coil that was successfully tested in the previous R&D phase.
Date: August 23, 2006
Creator: Martovetsky, N. N.
Partner: UNT Libraries Government Documents Department

Void fraction correlations in two-phase horizontal flow

Description: This study examines some physical mechanisms which impose limits on the possible existence of two-phase flow in a horizontal pipe. With the aid of this analysis and the use of the Martinelli variable, X, a method is developed which determines the range of possible void fractions for a given two-phase flow. This method affords a means of direct comparison among void fraction correlations, as well as between correlation predictions and experimental results. In this respect, four well-known void fraction correlations are compared against each other and with experimental results obtained in the Brown University Two-Phase Flow Research Facility.
Date: May 1, 1983
Creator: Papathanassiou, G.; Maeder, P.F.; DiPippo, R. & Dickinson, D.A.
Partner: UNT Libraries Government Documents Department

Tank 241-BX-104 vapor sampling and analysis tank characterization report

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-BX-104. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedure that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department

Tank 241-SX-106 vapor sampling and analysis tank characterization report

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-SX-106. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedure that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department

Tank 241-T-107 vapor sampling and analysis tank characterization report

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-T-107. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedure that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department

Tank 241-B-103 vapor sampling and analysis tank characterization report

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-B-103. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedure that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department

WET SOLIDS FLOW ENHANCEMENT

Description: The yield locus, tensile strength and fracture mechanisms of wet granular materials were studied. The yield locus of a wet material was shifted to the left of that of the dry specimen by a constant value equal to the compressive isostatic stress due to pendular bridges. for materials with straight yield loci, the shift was computed from the uniaxial tensile strength, either measured in a tensile strength tester or calculated from the correlation, and the angle of internal friction of the material. The predicted shift in the yield loci due to different moisture contents compare well with the measured shift in the yield loci of glass beads, crushed limestone, super D catalyst and Leslie coal. Measurement of the void fraction during the shear testing was critical to obtain the correct tensile strength theoretically or experimentally.
Date: March 25, 2001
Partner: UNT Libraries Government Documents Department

Annular flow of R-134a through a high aspect ratio duct: Local void fraction, droplet velocity and droplet size measurements

Description: Local measurements were made in annular flow of R-134a through a vertical duct. Using a gamma densitometer, hot-film anemometer and laser Doppler velocimeter, profiles of void fraction, liquid droplet frequency and droplet velocity were acquired across the narrow test section dimension. Based upon these results, data for liquid droplet size were obtained and compared to previous experimental results from the literature. These data are useful for developing an improved understanding of practical two-phase refrigerant flows, and for assessment of advanced two-fluid computer codes.
Date: November 1, 1998
Creator: Trabold, T.A.; Kumar, R. & Vassallo, P.F.
Partner: UNT Libraries Government Documents Department

Detailed analyses of dynamic and static errors in neutron radiography testing

Description: Neutron radiography systems are being used for real-time visualization of the dynamic behavior as well as time-averaged measurements of spatial vapor fraction distributions for two phase fluids. The extraction of quantitative data on vapor-liquid flow fields is a significant advance in the methodology of fundamental two-phase flow experimentation. The data in the form of video images are typically recorded on videotape at 30 frames per second. Image analysis of the video pictures is used to extract time-dependent or time-averaged data. The determination of the average vapor fraction requires averaging of the logarithm of time-dependent intensity measurements of the neutron beam (gray scale distribution of the image) that passes through the fluid. This could be significantly different than averaging the intensity of the transmitted beam and then taking the logarithm of that term. This is termed the dynamic error (error in the time-averaged vapor fractions due t the inherent time-dependence of the measured data) and is separate from the static error (statistical sampling uncertainty). The results provide insight into the characteristics of these errors and help to quantify achievable bounds on the limits of these errors. The static error was determined by the uncertainties of measured beam intensities. It was found that the maximum static error increases as liquid thickness increases and can be reduced by increasing the neutron source strength. The dynamic error increased with large fluctuations in the local vapor fractions and with increasing liquid thickness. Detailed analyses of both sources of errors are discussed.
Date: January 1, 1999
Creator: Joo, H. & Glickstein, S.S.
Partner: UNT Libraries Government Documents Department

Tank 241-TY-104 vapor sampling and analysis tank characterization report

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-TY-104. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedures that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department

Tank 241-C-111 vapor sampling and analysis tank characterization report. Revision 1

Description: This report presents the details of the Hanford waste tank characterization study for tank 241-C-111. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedures that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.
Date: May 31, 1995
Creator: Huckaby, J. L.
Partner: UNT Libraries Government Documents Department