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Small-orifice tubes for minimizing dilution in exhaust-gas samples

Description: Report presenting an investigation to find a means of obtaining undiluted exhaust-gas samples from a Wright R-2600-B aircraft engine equipped with short individual stacks. Preliminary tests to aid in determining the best design, location, and orientation of orifices ranging in size. Results regarding the Briggs & Stratton engine tests and Wright aircraft engine tests are provided.
Date: February 1943
Creator: Cook, Harvey A. & Olson, Walter T.
Partner: UNT Libraries Government Documents Department

Automatic Dilution Gaging of Rapidly Varying Flow

Description: From introduction: The purpose of this report is to develop and evaluate a method to automate the constant-rate-injection technique, described by Cobb and Bailey, with sufficient accuracy and reliability to determine discharge in storm sewers under rapidly varying flow conditions.
Date: October 1983
Creator: Duerk, Marvin D.
Partner: UNT Libraries Government Documents Department

Derivation of Equivalent Continuous Dilution for Cyclic, Unsteady Driving Forces

Description: This article uses an analytical approach to determine the dilution of an unsteadily-generated solute in an unsteady solvent stream, under cyclic temporal boundary conditions. The goal is to find a simplified way of showing equivalence of such a process to a reference case where equivalent dilution is defined as a weighted average concentration. This derivation has direct applications to the ventilation of indoor spaces where indoor air quality and energy consumption cannot in general be simultaneously optimized. By solving the equation we can specify how much air we need to use in one ventilation pattern compared to another to obtain same indoor air quality. Because energy consumption is related to the amount of air exchanged by a ventilation system, the equation can be used as a first step to evaluate different ventilation patterns effect on the energy consumption. The use of the derived equation is demonstrated by representative cases of interest in both residential and non-residential buildings.
Date: December 15, 2010
Creator: Laboratory, Lawrence Berkeley National; Technical University of Denmark, Department of Civil Engineering; Mortensen, Dorthe K.; Walker, Iain S. & Sherman, Max H.
Partner: UNT Libraries Government Documents Department

HB-Line Dissolver Dilution Flows and Dissolution Capability with Dissolver Charge Chute Cover Off

Description: A flow test was performed in Scrap Recovery of HB-Line to document the flow available for hydrogen dilution in the dissolvers when the charge chute covers are removed. Air flow through the dissolver charge chutes, with the covers off, was measured. A conservative estimate of experimental uncertainty was subtracted from the results. After subtraction, the test showed that there is 20 cubic feet per minute (cfm) air flow through the dissolvers during dissolution with a glovebox exhaust fan operating, even with the scrubber not operating. This test also showed there is 6.6 cfm air flow through the dissolvers, after subtraction of experimental uncertainty if the scrubber and the glovebox exhaust fans are not operating. Three H-Canyon exhaust fans provide sufficient motive force to give this 6.6 cfm flow. Material charged to the dissolver will be limited to chemical hydrogen generation rates that will be greater than or equal to 25 percent of the Lower Flammability Limit (LFL) during normal operations. The H-Canyon fans will maintain hydrogen below LFL if electrical power is lost. No modifications are needed in HB-Line Scrap Recovery to ensure hydrogen is maintained less that LFL if the scrubber and glovebox exhaust fans are not operating.
Date: January 15, 2003
Creator: Hallman, D.F.
Partner: UNT Libraries Government Documents Department

Use of an Eductor to Reliably Dilute a Plutonium Solution

Description: Savannah River Site (SRS) in South Carolina is dissolving Pu239 scrap, which is a legacy from the production of nuclear weapons materials, and will later convert it into oxide form to stabilize it. An eductor has been used to both dilute and transfer a plutonium containing solution between tanks. Eductors have the advantages of simplicity and no moving parts. Reliable control of dilution is important because the geometry of the receiving tank could potentially allow a nuclear criticality. Dilution factor was to have been controlled by the appropriate choice of flow restrictor in the line between the plutonium solution tank and the eductor. However, dilution factors measured for liquid transfers with different flow restrictors showed unexpected trends, causing concern that the process was not well understood. As a result, the performance of the eductor and associated piping were analyzed using a mathematical model. The one dimensional, two phase model accounted for eductor performance and for air and vapor coming out of solution at low pressures. The unexpected trends were shown to be the result of variations in viscosities and densities of both the plutonium solution and the nitric acid solution used as both the motive fluid and diluent. The model agreed well with existing data and was then used to make pre-test predictions of flows for four solution transfers with good agreement. This provided confidence that the eductor system was a reliable method for obtaining specified dilution factors. Based on model results, recommendations were made and implemented for the operation of the eductor transfer system. One unexpected result of the analysis was the observation that slow corrosion inside the eductor is increasing the dilution factor, which is a conservative trend.
Date: March 23, 1999
Creator: Steimke, J.L.
Partner: UNT Libraries Government Documents Department

E-Area Performance Assessment Interim Measures Assessment FY2003

Description: Projected impacts on disposal limits of various studies have been estimated. Interim measures to compensate for the impacts are needed for the Engineered Trench and the Intermediate Level Vault. Interim measures are due to projected decreases in the radionuclide disposal limits derived from the groundwater pathway as a result of the Aquifer Source Node study and consideration of potential artificial dilution caused by the large size of the grid elements in the Intermediate Level Vault groundwater model. Recently, it became evident that, in the development of the groundwater model for the Slit Trenches, the selection of aquifer source nodes (i.e., the spatial elements of the saturated zone model into which the flux of radionuclides from the unsaturated zone model is introduced) was not optimum6. Optimizing the source nodes would likely result in increases in the resulting groundwater concentrations, which would suggest that the radionuclide disposal limits should be reduced. However, other studies may result in increases in disposal limits 7. Therefore, a decision was made to develop and implement an annual summary of the potential impact of technical studies and other information on radionuclide disposal limits and whether mitigating measures should be imposed pending completion and implementation of the studies. This report is the first such summary.
Date: October 15, 2003
Creator: Wilhite, E.L.
Partner: UNT Libraries Government Documents Department

The Effect of Compression Ratio, Cooled Exhaust Gas Mixed With Inlet Air, and Inlet-Air Temperature on the Knock-Limited Performance of a Full-Scale Single-Cylinder Engine

Description: Report presenting a study to determine the effect on the knock-limited permissible power output on the indicated specific fuel consumption and on the cylinder temperatures of exhaust-gas dilution of the inlet-air charge, inlet-air temperature without exhaust-gas dilation, and of compressible ratio.
Date: March 1944
Creator: Bolz, Ray E. & Breitwieser, Roland
Partner: UNT Libraries Government Documents Department

Application of a General Computer Algorithm Based on the Group-Additivity Method for the Calculation of Two Molecular Descriptors at Both Ends of Dilution: Liquid Viscosity and Activity Coefficient in Water at Infinite Dilution

Description: This paper presents the application of a commonly used computer algorithm based on the group-additivity method for the calculation of the liquid viscosity coefficient at 293.15 K and the activity coefficient at infinite dilution in water at 298.15 K or organic molecules.
Date: December 10, 2017
Creator: Naef, Rudolf & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Complexation of Plutonium (IV) with Fluoride at Variable Tempeartures

Description: Complexation of Pu(IV) with fluoride was studied by solvent extraction at 25, 40 and 55 C in 2.2 mol {center_dot} kg{sup -1} HClO{sub 4}. The distribution ratio of Pu(IV) between the organic and aqueous phases decreased as the concentration of fluoride was increased due to the formation of Pu(IV)-F complexes in the aqueous phase. Two complexes, PuF{sup 3+} and PuF{sub 2}{sup 2+}, were identified under the conditions in this work and their stability constants at 25, 40 and 55 C and I = 2.2 mol {center_dot} kg{sup -1} HClO{sub 4} were determined from the distribution data. The Specific Ion Interaction approach (SIT) was used to extrapolate the constants to the state of infinite dilution. Data from this work indicate that the complexation of Pu(IV) with fluoride is endothermic and entropy-driven. The complexation becomes stronger at higher temperatures.
Date: June 10, 2009
Creator: Xia, Yuanxian; Rao, Linfeng; Friese, Judah I.; Moore, Dean A. & Bachelor, P. P.
Partner: UNT Libraries Government Documents Department

PERFORMANCE OF THE AGS TRANSITION JUMP SYSTEM.

Description: The transition jump system has been indispensable to the high intensity proton operation of the AGS complex. Nevertheless, transition crossing remains one of the major hurdles as the accelerator complex intensity is pushed upward. To enhance the performance of the system ''quadrupole pumping'' in the Booster is used to minimize the necessary longitudinal dilution of the beam on the AGS injection porch. During the transition jump sextupole correctors at strategic locations are pulsed to minimize the effects of the chromatic non-linearity of the jump system. The available instrumentation for diagnosing the performance of the system will be described, along with installed hardware to counter the non-linear effects of the transition jump system.
Date: March 29, 1999
Creator: AHRENS,L. A.; BRENNAN,J. M.; GLENN,J. W.; ROSER,T. & VAN ASSELT,W. K.
Partner: UNT Libraries Government Documents Department

Eliminating the Spot Dilution Due to Kicker Switching in DARHT-II

Description: To produce four short x-ray pulses for radiography, the second-axis of the Dual Axis Radiographic Hydrodynamic Test facility (DARHT-II) will use a fast kicker to select current pulses out of the 2-ms duration beam provided by the accelerator. Beam motion during the kicker voltage switching could lead to dilution of the time integrated beam spot and make the spot elliptical. A large elliptical x-ray source produced by those beams would degrade the resolution and make radiographic analysis difficult. We have developed a tuning strategy to eliminate the spot size dilution, and tested the strategy successfully on ETA-II with the DARHT-II kicker hardware.
Date: May 6, 2003
Creator: Chen, Y-J; Chambers, F W; Paul, A C; Watson, A & Weir, J T
Partner: UNT Libraries Government Documents Department

Iso-adiabatic merging of pbar stacks in the Fermilab Recycler

Description: Considerable longitudinal emittance (LE) dilution is seen during merging of two stacks of pbars in the Fermilab Recycler. The emittance dilution results from the sequence of RF manipulations used for merging. Here I present a new scheme for merging two stacks adiabatically. This involves energy matching of the two stacks before merging. An analytical expression is derived for energy matching condition. The scheme is illustrated with multi-particle beam dynamics simulations and beam measurements. The beam experiments have shown that one can preserve the emittance to better than 15%.
Date: May 1, 2005
Creator: Bhat, C. M. & /Fermilab
Partner: UNT Libraries Government Documents Department

Measurements with a recuperative superfluid Stirling refrigerator

Description: A superfluid Stirling refrigerator cooled to 168 mK using a 4.9% {sup 3}He- {sup 4}He mixture and exhausting its waste heat at 383 mK. Cooling power versus temperature and speed is presented for 4.9%, 17%, and 36% mixtures. At the highest concentration, a dissipation mechanism of unknown origin is observed.
Date: August 1, 1995
Creator: Watanabe, A.; Swift, G.W. & Brisson, J.G.
Partner: UNT Libraries Government Documents Department

Dry Blending to Achieve Isotopic Dilution of Highly Enriched Uranium Oxide Materials

Description: The end of the cold war produced large amounts of excess fissile materials in the United States and Russia. The Department of Energy has initiated numerous activities to focus on identifying material management strategies for disposition of these excess materials. To date, many of these planning strategies have included isotopic dilution of highly enriched uranium as a means of reducing the proliferation and safety risks. Isotopic dilution by dry blending highly enriched uranium with natural and/or depleted uranium has been identified as one non-aqueous method to achieve these risk (proliferation and criticality safety) reductions. This paper reviews the technology of dry blending as applied to free flowing oxide materials.
Date: April 1, 2001
Creator: Henry, Roger Neil; Chipman, Nathan Alan & Rajamani, R. K.
Partner: UNT Libraries Government Documents Department

A novel scheme to handle highly pulsed loads with a standard helium refrigerator

Description: Helium refrigerator performance degrades rapidly when it has to handle a varying or pulsed heat load. A novel scheme is presented to handle highly pulsed 4.5 K cryogenic loads with a standard helium refrigerator by isolating it from these pulses. The scheme uses a relatively simple arrangement of control valves, heat exchangers, and a storage dewar. Applications include pulsed tokamak machines such as TPX (Tokamak Physics Experiment) and ITER (International Thermonuclear Experimental Reactor). For example, the TPX (currently in the conceptual design phase in a DoE contract) requires an average 4.5 K refrigerator capacity of about 10 kW; however, pulsed loads caused by eddy current and nuclear heating will exceed 100 kW. The scheme presented here provides a method for handling these pulsed loads. Because of the simple and proven nature of the components involved and the thermodynamic properties of the helium, the system could be implemented for projects such as TPX or ITER with little or no development.
Date: June 30, 1993
Creator: Slack, D. S.
Partner: UNT Libraries Government Documents Department

Static and Flow Properties of Dilute Polymer Solutions

Description: Small weight percentages of certain high-molecular weight polymers added to liquids in turbulent flow through conduits can result in dramatic friction reduction. Although many current and potential uses of the drag reduction phenomenon exist, there is a fundamental problem: drag reduction efficacy decreases rapidly with flow time due to the mechanical degradation in flow of the added polymer. In this thesis study, dilute aqueous solutions of polyacrylamide were tested under turbulent flow conditions in an attempt to determine where mechanical degradation in flow occurs.
Date: August 1991
Creator: Whang, Kyu-ho
Partner: UNT Libraries

Experience with small turbomachinery in a 400 watt refrigerator

Description: A refrigerator similar to one of the Fermilab Tevatron satellites was reconfigured to use turbomachinery instead of the reciprocating equipment typical of the installations. A Sulzer dry turboexpander, Creare wet turboexpander, and IHI centrifugal cold compressor have been installed and operated for about 8000 hours. Experience was gained both with the rotating machinery and with the refrigerator itself as it interfaced with the load. Equipment was set up to regulate in the same manner as the reciprocating devices had. Heat load and operating mode were adjusted and evaluations made regarding the behavior of the devices. Individual equipment performance is described as well as system behavior and overall integration of the machinery. In particular, attention is paid to the Creare wet turboexpander. This device is operated for the first time as part of a full scale refrigeration system, testing not only its performance at the design point but also its off design characteristics and behavior in transient situations.
Date: September 1, 1996
Creator: Fuerst, J.D.
Partner: UNT Libraries Government Documents Department

A new antiproton beam transfer scheme without coalescing

Description: An effective way to increase the luminosity in the Fermilab Tevatron collider program Run2 is to improve the overall antiproton transfer efficiency. During antiproton coalescing in the Main Injector (MI), about 10-15% particles get lost. This loss could be avoided in a new antiproton transfer scheme that removes coalescing from the process. Moreover, this scheme would also eliminate emittance dilution due to coalescing. This scheme uses a 2.5 MHz RF system to transfer antiprotons from the Accumulator to the Main Injector. It is then followed by a bunch rotation in the MI to shorten the bunch length so that it can be captured by a 53 MHz RF bucket. Calculations and ESME simulations show that this scheme works. No new hardware is needed to implement this scheme.
Date: June 4, 2003
Creator: al., Weiren Chou et
Partner: UNT Libraries Government Documents Department