Report on the COMMIX-PPC computer program, designed to evaluate the thermal performance of power plant condensers. This first volume "describes in detail the basic equations, formulation, solution procedures, and models for auxiliary phenomena" (p. iv).

This report reviews the activities and operations of the Advanced Computing Research Facility (ACRF) for the period January 1, 1989, through January 31, 1990. The ACRF is operated by the Mathematics and Computer Science Division at Argonne National Laboratory. The facility's principal objective is to foster research in parallel computing. Toward this objective, the ACRF continues to operate experimental advanced computers and to sponsor new technology transfer efforts and new research projects.

The temperature dependence of glass durability, particularly that of nuclear waste glasses, is assessed by reviewing past studies. The reaction mechanism for glass dissolution in water is complex and involves multiple simultaneous reaction proceeded, including molecular water diffusion, ion exchange, surface reaction, and precipitation. These processes can change in relative importance or dominance with time or changes in temperature. The temperature dependence of each reaction process has been shown to follow an Arrhenius relationship in studies where the reaction process has been isolated, but the overall temperature dependence for nuclear waste glass reaction mechanisms is less well understood, Nuclear waste glass studies have often neglected to identify and characterize the reaction mechanism because of difficulties in performing microanalyses; thus, it is unclear if such results can be extrapolated to other temperatures or reaction times. Recent developments in analytical capabilities suggest that investigations of nuclear waste glass reactions with water can lead to better understandings of their reaction mechanisms and their temperature dependences. Until a better understanding of glass reaction mechanisms is available, caution should be exercised in using temperature as an accelerating parameter.

By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study is presented for chaotic vibrations associated with the fluid-elastic instability of nonlinearly supported tubes in a crossflow. Effective tools, including phase portraits, power spectral density, Poincare maps, Lyapunov exponent, fractal dimension, and bifurcation diagrams, are utilized to distinguish periodic and chaotic motions when the tubes vibrate in the instability region. The results show periodic and chaotic motions in the region corresponding to fluid-damping-controlled instability. Nonlinear supports, with symmetric or asymmetric gaps, significantly affect the distribution of periodic, quasi-periodic, and chaotic motions of a tube exposed to various flow velocities in the instability region of the tube-support-plate-inactive mode.

A research reactor for exclusive use in experimental radiobiology was designed and built at Argonne National Laboratory in the 1960`s. It was located in a special addition to Building 202, which housed the Division of Biological and Medical Research. Its location assured easy access for all users to the animal facilities, and it was also near the existing gamma-irradiation facilities. The water-cooled, heterogeneous 200-kW(th) reactor, named JANUS, became the focal point for a range of radiobiological studies gathered under the rubic of "the JANUS program". The program ran from about 1969 to 1992 and included research at all levels of biological organization, from subcellular to organism. More than a dozen moderate- to large-scale studies with the B6CF₁ mouse were carried out; these focused on the late effects of whole-body exposure to gamma rays or fission neutrons, in matching exposure regimes. In broad terms, these studies collected data on survival and on the pathology observed at death. A deliberate effort was made to establish the cause of death. This archieve describes these late-effects studies and their general findings. The database includes exposure parameters, time of death, and the gross pathology and histopathology in codified form. A series of appendices describes all …

In casting, fluidity is the measure of the distance a metal can flow in a channel before being stopped by solidification. During mold filling, the metal loses heat to the surrounding mold, thereby cooling and becoming more viscous until the leading portion solidifies and no further flow is possible. A coupled heat-transfer and fluid-flow modeling of a spiral, involving the use of thermophysical properties to determine material fluidity, has been conducted. Simulations of these experiments utilized the Casting Process Simulator (CaPS) software developed at Argonne National Laboratory. Two types of spiral geometries with different assumptions were considered: (1) a two-dimensional laterally stretched spiral and (2) a three-dimensional lateral spiral. The computer extent of mold filling is in good agreement with the experimental results. Time required by the metal/gas interface to attain specific positions in the spiral arm also compares favorably with the experimental results. The influence of process variables, especially pour time, is discussed. The CaPS software has been used as a computational tool to investigate the validity of the dimensionality assumptions and to evaluate the ability of CaPS to model fluidity adequately.

The solution of large sparse systems of linear equations is at the heart of many algorithms in scientific computing. The SLES package is a set of easy-to-use yet powerful and extensible routines for solving large sparse linear systems. The design of the package allows new techniques to be used in existing applications without any source code changes in the applications.

This Argonne report serves as a companion to our CADE-10 paper. To fulfill promises made in that paper, included here are detailed proofs in clause notation, input files compatible with OTTER, and explanations for the choice of approach. Also included are certain of the original and unpublished proofs (of Winker) that answered four open questions, two in equivalent calculus and two in the R-calculus. The organization parallels that of the CADE-10 paper.

The Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) sponsored by the US Department of Energy (DOE) was initiated to assess the performance of various heat-exchanger materials to be used in fluidized-bed combustion air heater systems. Westinghouse Electric Corporation, through subcontracts with Babcock Wilcox, Foster Wheeler, and ABB Combustion Engineering Systems, prepared specifications and hardware for the ACAHE tests. Argonne National Laboratory contracted with Rockwell International to conduct tests in the DOE atmospheric fluidized-bed combustion facility. This report presents an overview of the project, a description of the facility and the test hardware, the test operating conditions, a summary of the operation, and the results of analyzing specimens from several uncooled and cooled probes exposed in the facility. Extensive microstructural analyses of the base alloys, claddings, coatings, and weldments were performed on specimens exposed in several probes for different lengths of time. Alloy penetration data were determined for several of the materials as a function of specimen orientation and the exposure location in the combustor. Finally, the data were compared with earlier laboratory test data, and the long-term performance of candidate materials for air-heater applications was assessed.

This document reports on the work done by the Nuclear Waste Management Section of the Chemical Technology Division (CMT), Argonne National Laboratory, in the period October 1993-September 1994. Studies have been performed to evaluate the performance of nuclear waste glass and spent fuel samples under unsaturated conditions (low volume water contact) that are likely to exist in the Yucca Mountain environment being considered as a potential site for a high-level waste repository. Tests with simulated waste glasses have been in progress for over eight years and demonstrate that actinides from initially fresh glass surfaces will be released as a result of the spallation of reacted glass layers from the surface, as the small volume of water passes over the waste form.