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Theory and Application of a Quasi-Eulerian Fluid Element for the STRAW Code

Description: Two-dimensional finite-element models for the treatment of the nonlinear, transient response of fluids and structures are described. The fluid description is quasi-Eulerian, so that the mesh can move independently of the material, and it includes a new finite-element up-winding scheme. The structural description is based on a co-rotational formulation in which the coordinate system is embedded in the elements, which is applicable to arbitrarily large rotations. The interface between the fluid and structure permits relative sliding, but because of the description of the quasi-Eulerian fluid, the nodes of the fluid and structure can be allowed to remain contiguous. Modeling procedures for treating the various aspects of subassemblies, such as the narrow fluid channels, the fuel bundles which are immersed in the coolant, and the axial flow are developed. Calculations are made for a symmetric 7-subassembly cluster and compared to experimental results. In addition, the application to a 19-subassembly cluster is described.
Date: 1978
Creator: Kennedy, J. M. & Belytschko, Ted B.

Fluctuation Analysis of Fast Reactor Safety Experiments in TREAT

Description: Statistical fluctuations of measured signals about their mean are related to physical processes in fuel-failure experiments. Signal variance, correlation, and spectral density are shown to be sensitive measures to instrument response characteristics, of flow-blockage formation, and of boiling phenomena. This sensitivity is demonstrated by a series of examples that use test data from the E6, E7, and L5 experiments. A mathematical model of the Mark-II loop is developed to predict both the mean and the fluctuation behavior of measured test parameters. The analysis is extended to include signal forecasting by the ARIMA time-series model. Techniques that are used to identify the model and to estimate the model parameters are discussed in detail. It is shown that departure of real-time data from the on-line forecasts is a powerful tool for the rapid detection of off-normal conditions. A description of the experiments and the data-reduction process is given in the Appendices.
Date: November 1978
Creator: Doerner, R. C.; Meek, C. C.; Hurt, R. F. & Pekarsky, M. I.

The Current Status of Fusion Reactor Blanket Thermodynamics

Description: The available thermodynamic information is reviewed for three categories of materials that meet essential criteria for use as breeding blankets in deuterium-tritium (D-T) fueled fusion reactors: liquid lithium, solid lithium alloys, and lithium-containing ceramics. The leading candidate, liquid lithium, which also has potential for use as a coolant, has been studied more extensively than have the solid alloys or ceramics.
Date: April 1979
Creator: Veleckis, E.; Yonco, R. M. & Maroni, V. A.

Analysis of Nonlinear Fluid Structure Interaction Transient in Fast Reactors

Description: A generalized Eulerian method is described for analyzing the fluid transients and the structural response in nuclear reactors under the postulated accident conditions. The phenomena considered are the wave propagation, slug impact, sodium spillage, bubble migration, and the fluid-structure interaction. The basic equations and numerical formulation are presented in detail. Sample calculations are given to illustrate the analysis. It is shown from the results that the implicit, iterative method used is unconditionally stable and is especially suitable for problems involving large material distortions.
Date: 1978
Creator: Yang, C. Y.

Investigations of Materials Compatibility Relevant to the EBR-2 System : FY 1978

Description: This report is the ninth in a series of yearly reports on investigations of components of the EBR-II reactor plant and out-of-reactor experiments in which materials or techniques are tested before being used in the EBR-II reactor systems. Wide ranges of materials, circumstances, and evaluation techniques are involved. Therefore, each investigation is reported separately.
Date: January 1979
Creator: Longua, K. J.; Shields, J. A.; Ruther, W. E. & Olson, W. H.

EBR-2 Fisson-Product-Source Test No. 1

Description: A fission-product source (FPS) was irradiated in EBR-II to provide data for calibrating the facility's fuel-element rupture detector (FERD), which is a delayed-neutron monitor, and germanium-lithium argon-scanning system (GLASS), a fission-gas-activity monitor. A metal alloy source, Ni-3.2 wt.% uranium, provided quantitative recoil release of the fission-product nuclides. The source alloy, in tubular form, was irradiated as core-region segments of 18 capsules in the FPS subassembly. The irradiation showed that the response of the FERD was linear with increasing reactor power. The magnitude of the FERD signal was dependent on local fission rate for the FPS and the flow path of the sodium carrying the delayed-neutron emitters. The relatively high fission-gas activity released by the FPS allowed accurate calibration of the GLASS under several modes of operation and provided data for verifying a gas-release model for the reactor.
Date: August 1978
Creator: Strain, R. V.; Fogle, G. L.; Thresh, H. R.; Heinrich, R. R.; Freyer, R. M.; So, B. Y. C. et al.

Results of UO₂ Diagnositic Tests for Run Beyond Cladding Breach in EBR-2

Description: Pre-defected uranium dioxide fuel elements were irradiated in EBR-II to determine the response of the fission-product-monitoring systems. In particular, the tests were performed to indicate whether the amount of oxide fuel exposed to the primary sodium could be estimated by monitoring, with the fuel-element-rupture detector (FERD), delayed neutrons (DN's) emitted from bromine and iodine isotopes in the sodium. Elements with defect areas of 0.005 and 0.20 cm sq. were irradiated consecutively in April and June 1977. Post-irradiation examination of the elements showed that an unexpectedly large amount of uranium dioxide/sodium chemical reaction occurred in the element with the 0.20-cm sq. defect.
Date: 1979
Creator: Strain, R. V. & Lambert, J. D. B.

Creep-Fatigue Life Prediction for Different Heats of Type 304 Stainless Steel by Linear-Damage Rule, Strain-Range Partitioning Method, and Damage-Rate Approach

Description: The creep-fatigue life results for five different heats of Type 304 stainless steel at 593 degrees C (1100 degrees F), generated under push-pull conditions in the axial strain-control mode, are presented. The life predictions for the various heats based on the linear-damage rule, strain-range partitioning method, and damage-rate approach are discussed. The appropriate material properties required for computation of fatigue life are also included.
Date: July 1978
Creator: Maiya, P. S.

Bilinear Cyclic Stress-Strain Parameters for Types 304 and 316 Stainless Steel

Description: The bilinear cyclic stress-strain parameters for Types 304 and 316 stainless steel are described. The bilinear properties of solution-annealed and aged Type 304 stainless steel (heat 9T2796) and solution-annealed Type 3l6 stainless steel (heat 8092297) under cyclic-loading conditions at a strain rate of 8.6 x 10⁵ s⁻¹, total strain range between 0.2 and 0.8 percent, and temperatures from 22 to 593 degrees C were determined. The dependence of bilinear parameters on maximum strain epsilon and temperature is discussed.
Date: July 1978
Creator: Maiya, P. S.

An Ultrasonic Scanner for Stainless Steel Weld Inspections

Description: The large grain size and anisotropic nature of stainless steel weld metal make conventional ultrasonic testing very difficult. This paper evaluates a technique for minimizing the coherent noise in stainless steel weld metal. The method involves digitizing conventional A-scan traces and averaging them with a minicomputer. Results are presented for an ultrasonic scanner which interrogates a small volume of the weld metal while averaging the coherent ultrasonic noise.
Date: September 1978
Creator: Kupperman, D. S. & Reimann, K. J.

Second Mechanized In-Service Inspection of EBR-2 Steam Generator

Description: The second mechanized ultrasonic inspection of evaporation EV-702, part of the EBR-II steam-generator system, was completed in March 1978. The 2 1/2 Cr-1 Mo duplex tubes were inspected from the bore (water) side for flaws and changes in wall thickness and for evaluating the condition of the braze between the tubes. An addition to this second inspection was the use of an ultrasonic probe to search for circumferential flaws. The inspection equipment was thoroughly checked and routinely calibrated, using a reference standard containing electrical-discharge-machined notches. Notches as small as 1.6 mm long by 0.25 mm deep were readily detected.
Date: November 1978
Creator: Longua, K. J.; Whitham, G. K.; Allen, C. C. & Larson, H. A.

ATLAS: a Proposal for a Precision Heavy Ion Accelerator at Argonne National Laboratory

Description: The objective of the proposed Argonne Tandem-Linac Accelerator System (ATLAS) is to provide precision beams of heavy ions for nuclear physics research in the region of projectile energies comparable to nuclear binding energies (5-25 MeV/A). By using the demonstrated potential of superconducting radiofrequency technology, beams of exceptional quality and flexibility can be obtained. The system is designed to provide beams with tandem-like energy resolution and ease of energy variation, the energy range is comparable to that of approximately 50 MV tandem and, in addition, the beam will be bunched into very short (approximately 50 psec) pulses, permitting fast-timing measurements that can open up major new experimental approaches.
Date: February 1978
Creator: Bollinger, L. M.

Chemical Engineering Division Fuel Cycle Programs Progress Report: April-June 1978

Description: Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research. This report includes studies on advanced solvent extraction techniques focused on the development of centrifugal contactors for use in Purex processes, extraction kinetics of ruthenium and zirconium in the presence of uranium, and dispersion of uranium and plutonium by fires.
Date: December 1979
Creator: Steindler, M. J.; Ader, M.; Bernstein, G.; Flynn, K.; Gerding, T.; Jardine, L. J. et al.

Simple Procedure for Predicting Long-Term Average Performance of Nonconcentrating and of Concentrating Solar Collectors

Description: The Liu and Jordan method of calculating long term average energy collection of flat plate collectors is simplified (by about a factor of 4), and generalized to all collectors, concentration and non-concentrating. The only meteorological input needed are the long term average daily total hemispherical insolation H/sub h/ on a horizontal surface and, for thermal collectors the average ambient temperature. The collector is characterized by optical efficiency, heat loss (or U-value), heat extraction efficiency, concentration ratio and tracking mode. An average operating temperature is assumed. Interaction with storage can be included by combining the present model with the f-chart method of Beckman, Klein and Duffie. Formulas and examples are presented for five collector types: flat plate, compound parabolic concentrator, concentrator with E.-W. tracking axis, concentrator with polar tracking axis, and concentrator with two axis tracking. The examples show that even for relatively low temperature applications and cloudy climates (50 degrees C in New York in February), concentrating collectors can outperform the flat plate. The method has been validated against hourly weather data (with measurements of hemispherical and beam insolation), and has been found to have an average accuracy better than 3% for the long term average radiation available to solar collectors. The suitability of this method for comparison studies is illustrated by comparing in a location independent manner the radiation availability for several collector types or operating conditions: two axis tracking versus one axis tracking; polar tracking axis versus east-west tracking axis; fixed versus tracking flat plate; effect of ground reflectance; and acceptance for diffuse radiation as function of concentration ratio.
Date: June 1978
Creator: Collares-Pereira, Manuel & Rabl, Ari

Metallographic and Fractographic Observations of Posttest Creep-Fatigue Specimens of Weld-Deposited Type 308 CRE Stainless Steel

Description: Type 308 CRE stainless steel weld specimens were subjected to metallographic and fractographic analysis after failure in elevated temperature (593 degrees C) creep-fatigue tests. The failure mode for specimens tested under continuous-cycle fatigue conditions were predominantly transgranular. When the test cycle was modified to include a hold time at the maximum tensile strain, the failure mode became predominantly inter-phase. Sigma phase was observed within the delta-ferrite regions of the weld. However, the presence of sigma phase did not appear to affect the failure mode.
Date: August 1978
Creator: Williams, M. W.

Advanced Fuel Cell Development Progress Report: April-June 1978

Description: Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward understanding and improving the components of molten-carbonate-electrolyte fuel cells operated at temperatures near 925 K.
Date: August 1978
Creator: Ackerman, J. P.; Pierce, Robert Dean; Nelson, P. A.; Arons, R. M.; Kinoshita, K.; Sim, J. W. et al.


Description: A transient, two-dimensional code has been developed to provide a detailed description of fuel-clad conditions during a TOP accident. Emphasis has been directed toward development of a framework within which fuel motion and ejection can be viewed following pin failure. All code modules have been rigorously verified. Illustrative application of the code, with the exercise of its many and varied features, have been included.
Date: August 1978
Creator: Meek, C. C.

Project AN0115A Annual Report, 1976: Migration of Plutonium and Americium in the Lithosphere

Description: Annual report of Argonne National Laboratory project ANO115A. Abstract: Studies have been carried out on the migration of plutonium and americium in solutions flowing through porous and crushed rock and through fissures. The migration process can be described in terms of the surface absorption of these elements. In addition, chemical effects on the absorption have been observed. One of these effects is possibly due to the presence of a plutonium polymer that migrates at a more rapid rate than normal plutonium.
Date: 1976
Creator: Hines, J. J.; Friedman, A. M.; Fried, S.; Atcher, Robert Whitehill; Quarterman, L. A. & Volesky, A.

A Practical Approach to Availability and Irreversibility

Description: From Introduction: "The purpose of this paper is to shed additional light on the techniques of a Second Law Analysis. The stimulus for writing this paper came from questions asked and difficulties that occurred during lectures on the subject at the graduate level. This paper utilizes Keenan's basic approach but presents the material with emphasis upon a clear definition of the work associated with each subsystem in the process."
Date: June 1963
Creator: Hoglund, Barton M.