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Liquid metal Flow Meter - Final Report

Description: Measuring the flow of liquid metal presents serious challenges. Current commercially-available flow meters use ultrasonic, electromagnetic, and other technologies to measure flow, but are inadequate for liquid metal flow measurement because of the high temperatures required by most liquid metals. As a result of the reactivity and high temperatures of most liquid metals, corrosion and leakage become very serious safety concerns. The purpose of this project is to develop a flow meter for Lockheed Martin that measures the flow rate of molten metal in a conduit.
Date: January 30, 2007
Creator: Andersen C, Hoogendoom S, Hudson B, Prince J, Teichert K, Wood J, Chase K
Partner: UNT Libraries Government Documents Department

Laboratory experiments on dispersive transport across interfaces: The role of flow direction

Description: We present experimental evidence of asymmetrical dispersive transport of a conservative tracer across interfaces between different porous materials. Breakthrough curves are measured for tracer pulses that migrate in a steady state flow field through a column that contains adjacent segments of coarse and fine porous media. The breakthrough curves show significant differences in behavior, with tracers migrating from fine medium to coarse medium arriving significantly faster than those from coarse medium to fine medium. As the flow rate increases, the differences between the breakthrough curves diminish. We argue that this behavior indicates the occurrence of significant, time-dependent tracer accumulation in the resident concentration profile across the heterogeneity interface. Conventional modeling using the advection-dispersion equation is demonstrated to be unable to capture this asymmetric behavior. However, tracer accumulation at the interface has been observed in particle-tracking simulations, which may be related to the asymmetry in the observed breakthrough curves.
Date: April 1, 2009
Creator: Berkowitz, B.; Cortis, A.; Dror, I. & Scher, H.
Partner: UNT Libraries Government Documents Department

Quarterly Technical Progress Report

Description: Methane oxidative coupling experiments were conducted in a porous gamma alumina membrane reactor using Mn-W-Na/SiOz catalyst, and its performance was compared with a packed reactor. By varying the helium flow rate and keeping the temperature, methane flow rate, and oxygen flow rate constant, the membrane reactor gave 10% higher Cz yield and 30% higher C2 selectivity than the co-feed reactor operated at the same methane conversion. At similar C2 yield and C2 selectivity, the methane conversion of the membrane reactor was 15% lower than that of a co-feed reactor. By varying the oxygen flow rate and keeping the temperature, methane flow rate, and helium flow rate constant, at the same methane conversion, the membrane reactor gave about 3% higher C2 yield and C2 selectivity than the co-feed reactor. Higher helium flow rate gave higher C2 selectivity and yield, whereas changing methane flow rate did not significantly affect the reactor performance.
Date: August 29, 1997
Creator: Ma, Yi Hua
Partner: UNT Libraries Government Documents Department

Measuring rates of outdoor airflow into HVAC systems

Description: During the last few years, new technologies have been introduced for measuring the flow rates of outside air into HVAC systems. This document describes one particular technology for measuring these airflows, a system and a related protocol developed to evaluate this and similar measurement technologies under conditions without wind, and the results of our evaluations. We conclude that the measurement technology evaluated can provide a reasonably accurate measurement of OA flow rate over a broad range of flow, without significantly increasing airflow resistance.
Date: October 1, 2002
Creator: Fisk, William J.; Faulkner, David; Sullivan, Douglas P. & Delp, Woody
Partner: UNT Libraries Government Documents Department

Task 1 Steam Oxidation (NETL-US)

Description: Some conclusions are: (1) Increased flow rates can lower chromia activity in alloys with Ti and Mn - (a) Reduced chromia activity reduces equilibrium CrO{sub 2}(OH){sub 2}(g) vapor pressures; (2) Model is very sensitive to small decreases in chromia activity at the HP turbine - (a) Upstream partial saturation of the gas phase with CrO{sub 2}(OH){sub 2}(g) can become nearly or fully saturated at the HP turbine, (b) Can radically change breakaway oxidation times from less than a year to never happening; and (3) Thus even small chromia activity reductions from Ti and Mn additions can make evaporation issues self-correcting.
Date: April 28, 2011
Creator: Holcomb, G. R.; Tylczak, J. & R. Hu,
Partner: UNT Libraries Government Documents Department


Description: A solar test collector was designed for the testing of thermally absorbing coatings under controlled conditions. The design consisted of a collector fed by a controlled temperature fluid within the range of 25-90 C (77-194 F). This temperature was maintained by a custom electronic controller. A small variable flow pump circulated water through three collector pipes at selected flow rates. Strip heaters coupled with a differential temperature controller compensated for edge losses associated with small collectors. Detailed design and operation data were presented and three black chrome and one nonselective absorber were analyzed in detail by test collector measurements. Results showed efficiencies as high as 77% and 75% ({Delta}T = 0) were obtained respectively for 1.0 {micro}m black chrome on copper and nickel plated steel. The lowest loss coefficients were about 3.8 w/m{sup 2} C for all black chrome/metal surfaces with the highest being 8.4 w/m{sup 2} C for the black paint/metal sample. Also, a collector model was presented for comparison.
Date: June 1, 1978
Creator: Lampert, Carl M. & Washburn, Jack
Partner: UNT Libraries Government Documents Department

Studies of injection into naturally fractured reservoirs

Description: A semi-analytical model for studies of cold water injectioninto naturally fractured reservoirs has been developed. The model can beused to design the flow rates and location of injection wells in suchsystems. The results obtained using the model show that initially thecold water will move very rapidly through the fracture system away fromthe well. Later on, conductive heat transfer from the rock matrix blockswill retard the advancement of the cold water front, and eventuallyuniform energy sweep conditions will prevail. Where uniform energy sweepconditions are reached the cold waer movement away from the injectionwell will be identical to that in a porous medium; consequently maximumenergy recovery from the rock matrix will be attained. The time ofuniform energy sweep and the radial distance from the injection wellwhere it occurs are greatly dependent upon the fracture spacing, butindependent of the fracture aperture.
Date: July 1, 1982
Creator: Bodvarsson, Gudmundur S. & Lai, Cheng Hsien
Partner: UNT Libraries Government Documents Department

An evaluation of three commercially available technologies forreal-time measurement of rates of outdoor airflow into HVAC systems

Description: During the last few years, new technologies have been introduced for real-time continuous measurement of the flow rates of outdoor air (OA) into HVAC systems; however, an evaluation of these measurements technologies has not previously been published. This document describes a test system and protocols developed for a controlled evaluation of these measurement technologies. The results of tests of three commercially available measurement technologies are also summarized. The test system and protocol were judged practical and very useful. The three commercially available measurement technologies should provide reasonably, e.g., 20%, accurate measurements of OA flow rates as long as air velocities are maintained high enough to produce accurately measurable pressure signals. In HVAC systems with economizer controls, to maintain the required air velocities the OA intake will need to be divided into two sections in parallel, each with a separate OA damper. All of the measurement devices had pressure drops that are likely to be judged acceptable. The influence of wind on the accuracy of these measurement technologies still needs to be evaluated.
Date: October 28, 2004
Creator: Fisk, William J.; Faulkner, David & Sullivan, Douglas P.
Partner: UNT Libraries Government Documents Department

Measuring Outdoor Airflow into HVAC Systems

Description: The rate of outdoor air (OA) supply affects building energy consumption, occupant health, and work performance; however, minimum ventilation rates are often poorly controlled. Real-time measurements of OA flow rates into HVAC systems would enable improved flow control. This article demonstrates that at least some of the available technologies for real-time measurement of OA air intake rate are reasonably accurate and provides guidance on how these technologies should be used.
Date: August 1, 2005
Creator: Fisk, William J.; Faulkner, David & Sullivan, Douglas P.
Partner: UNT Libraries Government Documents Department

Real-Time Measurement of Rates of Outdoor Airflow into HVACSystems: A Field Study of Three Technologies

Description: Technologies for real-time continuous measurement of the flow rates of outdoor air (OA) into HVAC systems are now available commercially. Our prior papers reported on laboratory-based evaluations of these measurement technologies and this document describes the methods and results of a field study of the accuracy of three of these technologies. From the field study data, we determined that neither wind speed nor wind direction have an important adverse impact on measurement accuracy. The field study confirmed that these three measurement technologies can provide reasonably accurate measurements of outdoor air intake rates in field settings, if the pressure signals are measured with high accuracy. Some of the pressure transducers marketed for use with commercial HVAC systems were determined to be sufficiently accurate for this application. Given the significant impact of OA flow rates on both energy use and occupant health, more widespread use of technologies that provide for real time measurements of OA flow rates seems warranted.
Date: September 1, 2005
Creator: Fisk, William J.; Sullivan, Douglas P. & Faulkner, David
Partner: UNT Libraries Government Documents Department

An Inverted Co-Flow Diffusion Flame for Producing Soot

Description: We developed an inverted, co-flow, methane/air/nitrogen burner that generates a wide range of soot particles sizes and concentrations. By adjusting the flow rates of air, methane, and nitrogen in the fuel, the mean electric mobility diameter and number concentration are varied. Additional dilution downstream of the flame allows us to generate particle concentrations spanning those produced by spark-ignited and diesel engines: particles with mean diameters between 50 and 250 nm and number concentrations from 4.7 {center_dot} 10{sup 4} to 10{sup 7} cm{sup -3}. The range of achievable number concentrations, and therefore volume concentrations, can be increased by a factor of 30 by reducing the dilution ratio. These operating conditions make this burner valuable for developing and calibrating diagnostics as well as for other studies involving soot particles.
Date: June 21, 2005
Creator: Stipe, Christopher B.; Higgins, Brian S.; Lucas, Donald; Koshland, Catherine P. & Sawyer, Robert F.
Partner: UNT Libraries Government Documents Department

Two-phase viscoelastic jetting

Description: A coupled finite difference algorithm on rectangular grids is developed for viscoelastic ink ejection simulations. The ink is modeled by the Oldroyd-B viscoelastic fluid model. The coupled algorithm seamlessly incorporates several things: (1) a coupled level set-projection method for incompressible immiscible two-phase fluid flows; (2) a higher-order Godunov type algorithm for the convection terms in the momentum and level set equations; (3) a simple first-order upwind algorithm for the convection term in the viscoelastic stress equations; (4) central difference approximations for viscosity, surface tension, and upper-convected derivative terms; and (5) an equivalent circuit model to calculate the inflow pressure (or flow rate) from dynamic voltage.
Date: December 10, 2008
Creator: Yu, J.-D.; Sakai, S. & Sethian, J. A.
Partner: UNT Libraries Government Documents Department


Description: Tritium clean-up systems typically deploy gas processing technologies between stages of palladium-silver (Pd/Ag) diffusers/permeators. The number of diffusers positioned before and after a gas clean-up process to obtain optimal system performance will vary with feed gas inert composition. A simple method to analyze optimal diffuser configuration is presented. The method assumes equilibrium across the Pd/Ag tubes and system flows are limited by diffuser vacuum pump speeds preceding or following the clean-up process. A plot of system feed as a function of inert feed gas composition for various diffuser configuration allows selection of a diffuser configuration for maximum throughput based on feed gas composition.
Date: July 24, 2007
Creator: Klein, J & Dave W. Howard, D
Partner: UNT Libraries Government Documents Department

Leakage Rates for Cryolab Valves

Description: This note summarizes a brief study on the leakage rates of cryolab valves due to the failure of the valve packings. The {Delta}r gap between the shaft and the packing, the fluid (Ar or N2), the {Delta}p (atm) between the fluid and atmosphere, and the initial temperature of the escaping gas were varied to determine the resulting leakage rate. The heat leak in watts required to vaporize the liquid which provides the indicated flow rates is also included in the results. The dimensions used in the calculations were acquired over the telephone and/or found on the enclosed drawing from Cryolab. There is no implication that Cryolab was any better or worse than other valve manufacturers. They were kind enough to provide the detail needed for this study. The fluid properties were found in Ar and N2 Property handbooks. The results of this study are shown graphically and listed on accompanying spread sheets. The spread sheets and graphs can be found on the disc JW4 in the MassFlow folder.
Date: November 2, 1988
Creator: Wendlandt, J.M.
Partner: UNT Libraries Government Documents Department

D0 Silicon Upgrade: Control Dewar Venturi Calibration Explanation for Toshiba

Description: This document is intended to explain the calibration data for the venturi, FE-3253H, which is installed in the control dewar. Further, this document will help explain how to use the venturi to make mass flow measurements during typical operating conditions. The purpose of the calibration data enclosed from the Colorado Engineering Experiment Station Inc. is to experimentally show that the venturi follows the flow equation which is enclosed as Eq. 7-36 on page 155, from the Applied Fluid Dynamics Handbook. The calibration data serves to show that the Subsonic Venturi, Serial Number 611980-18, produces results predicted by the compressible subsonic flow mass flow rate equation above and to experimentally determine the discharge coefficient C. Colorado Engineering Experiment Station Inc. ran tests at 15 independent differential pressures to conclude that use of this venturi will perform according to the mass flow rate equation. In order to verify the results from the Colorado Engineering Experiment Station Inc. we have provided you with a step-by-step procedure using the values they have chosen.
Date: January 24, 1997
Creator: Kuwazaki, Andrew
Partner: UNT Libraries Government Documents Department

Tracer Recovery and Mixing from Two Geothermal Injection-Backflow Studies

Description: Injection-backflow tracer testing on a single well is not a commonly used procedure for geothermal reservoir evaluation, and, consequently, there is little published information on the character or interpretation of tracer recovery curves. Two field experiments were conducted to develop chemical tracer procedures for use with injection-backflow testing, one on the fracture-permeability Raft River reservoir and the other on the matrix-permeability East Mesa reservoir. Results from tests conducted with incremental increases in the injection volume at both East Mesa and Raft River suggests that, for both reservoirs, permeability remained uniform with increasing distance from the well bore. Increased mixing during quiescent periods, between injection and backflow, at Raft River suggest an area near the well bore that has a hydrologic character different from the far well bore environment. Increased flow rates for East Mesa testing resulted in a general decrease in mixing. Comparison of recovery curves from the Raft River reservoir with those from the East Mesa reservoir suggests that mixing is greatest, and therefore permeability is greatest, in the fractured reservoir. These test results indicate that injection-backflow testing with tracers can be used successfully to characterize flow in the near-well bore environment.
Date: December 15, 1983
Creator: Capuano, R.M.; Adams, M.C. & Wright, P.M.
Partner: UNT Libraries Government Documents Department

Effects of Natural Environmental Changes on Soil-Vapor Extraction Rates

Description: Remediation by soil-vapor extraction has been used for over a decade at Lawrence Livermore National Laboratory (LLNL). We have found that natural changes in environmental conditions affect the rate of soil-vapor extraction. Data on flow rate observations collected over this time are compared to in-situ measurements of several different environmental parameters (soil-gas pressure, soil-temperature, soil-moisture, Electrical Resistance Tomography (ERT), rainfall and barometric pressure). Environmental changes that lead to increased soil-moisture are associated with reduced soil-vapor extraction flow rates. We have found that the use of higher extraction vacuums combined with dual-phase extraction can help to increase pneumatic conductivity when vadose zone saturation is a problem. Daily changes in barometric pressure and soil-gas temperature were found to change flow rate measurements by as much as 10% over the course of a day.
Date: March 23, 2006
Creator: Martins, S & Gregory, S
Partner: UNT Libraries Government Documents Department

Enhancement of Equilibriumshift in Dehydrogenation Reactions Using a Novel Membrane Reactor

Description: In our previous report we reported technical difficulties encountered in the fabrication of tubular membrane reactor using our Pd-ceramic composite membranes. Although the membrane is highly selective to hydrogen but in test runs we observed leakage of hydrogen from the end-seals and metallic fittings. This was a serious problem. An attempt to improve the seal by tightening was not helpful but resulted in cracks and breakage of the ceramic tube. To test the equilibrium conversion and equilibrium shift effect on dehydrogenation of cyclohexane to benzene and hydrogen in membrane reactor, we used Pd-ceramic discs in our diffusion cell as reactor packed with Pt-catalyst pellets. Test results show that by manipulating the feed (cyclohexane) flow rate and sweep gas flow rate (permeate side) we can have over 55% conversion as opposed to 18.7% equilibrium conversion under identical conditions. This demonstrates the usefulness of the new membrane in H{sub 2} separation and also in membrane-reactor configurations for equilibrium limited decomposition and dehydrogenation reactions.
Date: March 29, 2000
Creator: Ilias, Shamsuddin & King, Franklin G.
Partner: UNT Libraries Government Documents Department

Yakima River Basin Phase II Fish Screen Evaluations, 2002

Description: In 2002, the Pacific Northwest National Laboratory evaluated 23 Phase II fish screen sites in the Yakima River Basin as part of a multi-year project for the Bonneville Power Administration on the effectiveness of fish screening devices. Pacific Northwest National Laboratory collected data to determine whether velocities in front of the screens and in the bypasses met National Marine Fisheries Service criteria to promote safe and timely fish passage and whether bypass outfall conditions allowed fish to safely return to the river. In addition, Pacific Northwest National Laboratory conducted underwater video surveys to evaluate the environmental and operational conditions of the screen sites with respect to fish passage. Based on evaluations in 2002, PNNL concluded that: (1) In general, water velocity conditions at the screen sites met fish passage criteria set by the National Marine Fisheries Service. (2) Conditions at most facilities would be expected to provide for safe juvenile fish passage. (3) Conditions at some facilities indicate that operation and/or maintenance should be modified to increase safe juvenile fish passage. (4) Automated cleaning brushes generally functioned properly; chains and other moving parts were typically well greased and operative. (5) Removal of sediment buildup and accumulated leafy and woody debris should be improved at some sites.
Date: March 1, 2003
Creator: Carter, Jessica A.; McMichael, Geoffrey A. & Chamness, Mickie A.
Partner: UNT Libraries Government Documents Department