This report is concerned with eigenvalue problems of the form Au = lambda Tu, where A is a selfadjoint positive differential operator and T a selfadjoint indefinite multiplicative operator on a Hilbert space H. Three particular cases are discussed in detail. In the first case, A is positive definite and T is unitary; in the second case, A is positive definite and T is bounded, but T⁻¹ is unbounded; in the third case, A is positive, dim ker(A) = 1, and T is bounded, but T⁻¹is unbounded. Emphasis is on the full-range and half-range expansion properties of the eigenfunctions.

Working fluids used in Rankine bottoming cycle systems for heat recovery from long-haul trucks, marine vessels, and railroad locomotives are examined. Rankine bottoming cycle systems improve fuel economy by converting the exhaust heat from the prime mover into useful power. The report assesses fluid property requirements on the basis of previous experience with bottoming cycle systems. Also, the exhaust gas characteristics for the transportation modes of interest are summarized and compared. Candidate working fluids are discussed with respect to their potential for use in Rankine bottoming cycle systems. Analytical techniques are presented for calculating the thermodynamic properties of single-component working fluids. The resulting equations have been incorporated into a computer code for predicting the performance of Rankine bottoming cycle systems. In evaluating candidate working fluids, the code requires the user to input only a minimal amount of fluid property data.

A nodal method is developed for the solution of the neutron-diffusion equation in two- and three-dimensional hexagonal geometries. The nodal scheme has been incorporated as an option in the finite-difference diffusion-theory code DIF3D, and is intended for use in the analysis of current LMFBR designs. The nodal equations are derived using higher-order polynomial approximations to the spatial dependence of the flux within the hexagonal-z node. The final equations, which are cast in the form of inhomogeneous response-matrix equations for each energy group, involved spatial moments of the node-interior flux distribution plus surface-averaged partial currents across the faces of the node. These equations are solved using a conventional fission-source iteration accelerated by coarse-mesh rebalance and asymptotic source extrapolation. This report describes the mathematical development and numerical solution of the nodal equations, as well as the use of the nodal option and details concerning its programming structure. This latter information is intended to supplement the information provided in the separate documentation of the DIF3D code.

This report summarizes the work completed on a project concerned with engineering models in dynamic plasticity. The concept of the endochronic theory of viscoplasticity and its subsequent improvement are discussed briefly. Applications and extensions of the theory to various dynamic problems are presented. In particular, the strain-rate effect in the improved endochronic theory and its application to wave propagation problems are discussed. Comparing the numerical results with other calculations and experimental data, it appears that endochronic theory provides a promising representation of realistic material behavior. At the same time endochronic theory is often numerically more efficient than other formulations.

In the process of learning how to write code for the Denelcor HEP, we have developed an approach that others may well find useful. We believe that the basic synchronization primitives of the HEP (i.e., asynchronous variables), along with the prototypical patterns for their use given in the HEP FORTRAN 77 User's Guide, form too low-level a conceptual basis for the formulation of multiprocessing algorithms. We advocate the use of monitors, which can be easily implemented using the HEP primitives. Attempts to solve substantial problems without introducing higher-level constructs such as monitors can produce code that is unreliable, unintelligible, and restricted to the specific dialect of FORTRAN currently supported on the HEP. Our experience leads us to believe that solutions which are both clear and efficient can be formulated using monitors.

In a previous paper, the advantages of using monitors when implementing multiprocessing algorithms for the Denelcor HEP were delineated. A detailed presentation is given here of how monitors can be implemented on the HEP using a simple macro processor. The thesis is developed that a small body of general-purpose monitors can be defined to handle most standard synchronization patterns. We include the macro packages required to implement some of the more common synchronization patterns, including the fairly complex logic discussed before. Code produced using these macro packages is portable from one multiprocessing environment to another. Indeed, by recoding the set of basic macros (about 100 lines of code for the Denelcor HEP), most programs that are now being written could be moved to any similar multiprocessing system.

Three liquid-based solar heating systems employing different types of solar collectors were tested side by side near Chicago, Illinois for one year. The three different types of collectors were: (1) a flat plate collector with a black-chrome coated absorber plate and one low-iron glass cover; (2) an evacuated-tube compound parabolic concentrator (CPC) with a concentration ratio of 1.1, oriented with tubes and troughs along a north-south axis; and (3) an evacuated-tube CPC collector with a concentration ratio of 1.3 and one low-iron glass cover, with tubes and troughs oriented along an east-west axis. Results indicate that the flat plate collector system was the most efficient during warm weather, but the CPC systems were more efficient during cold weather, but the CPC systems were more efficient during cold weather, and the CPC systems operated under conditions too adverse for the flat plate collector. The computer simulation model ANSIM was validated by means of the side-by-side tests. The model uses analytical solutions to the storage energy balance. ANSIM is compared with the general simulation TRNSYS.

ANL/HTP is a computer code for the simulation of heat pipe operation, to predict heat pipe performance and temperature distributions during steady state operation. Source and sink temperatures and heat transfer coefficients can be set as input boundary conditions, and varied for parametric studies. Five code options are included to calculate performance for fixed operating conditions, or to vary any one of the four boundary conditions to determine the heat pipe limited performance. The performance limits included are viscous, sonic, entrainment capillary, and boiling, using the best available theories to model these effects. The code has built-in models for a number of wick configurations - open grooves, screen-covered grooves, screen-wrap, and arteries, with provision for expansion. The current version of the code includes the thermophysical properties of sodium as the working fluid in an expandable subroutine. The code-calculated performance agrees quite well with measured experiment data.

A central solar-heating plant with seasonal heat storage in a deep underground aquifer is designed by means of a solar-seasonal-storage-system simulation code based on the Solar Energy Research Institute (SERI) code for Solar Annual Storage Simulation (SASS). This Solar Seasonal Storage Plant is designed to supply close to 100% of the annual heating and domestic-hot-water (DHW) load of a hypothetical new community, the Fox River Valley Project, for a location in Madison, Wisconsin. Some analyses are also carried out for Boston, Massachusetts and Copenhagen, Denmark, as an indication of weather and insolation effects. Analyses are conducted for five different types of solar collectors, and for an alternate system utilizing seasonal storage in a large water tank. Predicted seasonal performance and system and storage costs are calculated. To provide some validation of the SASS results, a simulation of the solar system with seasonal storage in a large water tank is also carried out with a modified version of the Swedish Solar Seasonal Storage Code MINSUN.

The susceptibility of a cantilevered tube conveying water to self-excitation by leakage flow through a slip joint is assessed experimentally. The slip joint is formed by inserting a smaller, rigid tube into the free end of the cantilevered tube. Variations of the slip joint annular gaps and engagement lengths are tested, and several mechanisms for self-excitation are described.

The primary-coolant flow paths of a reactor system are usually subject to close scrutiny in a design review to identify potential flow-induced vibration sources. However, secondary-flow paths through narrow gaps in component supports, which parallel the primary-flow path, occasionally are the excitation source for significant vibrations even though the secondary-flow rates are orders of magnitude smaller than the primary-flow rate. These so-called leakage flow problems are reviewed here to identify design features and excitation sources that should be avoided. Also, design rules of thumb are formulated that can be employed to guide a design, but quantitative prediction of component response is found to require scale-model testing.

Intergranular stress-corrosion crack (IGSCC) propagation rates were measured in three heats of sensitized Type 304 stainless steel (SS) as a function of sensitization in an environment of high-purity water with 8 ppm oxygen, using a fracture mechanics approach. Specimens were sensitized using controlled furnace heat treatments and the degree of sensitization was measured by the electrochemical potentiokinetic reactivation (EPR) method. Active loading tests were performed on standard specimens over a range of intensities. Crack lengths were determined by compilance measurements using in-situ high-temperature clip gage or LVDT methods, optical metallography on the side faces of the specimen, and fractography of the cracked surface after completion of the tests. The optical metallography measurements did not provide useful estimates of crack lengths, because large variations in IGSCC propagation across the thickness of the specimens occurred. The effects of the degree of sensitization on the IGSCC propagation rate are obscured by the data scatter. However, it seems clear that these variables do not lead to order-of-magnitude changes in the crack propagation rate.

This report reviews the research activities in Applied Mathematical Sciences at Argonne National Laboratory for the period April 1, 1982, through March 31, 1983. The body of the report discusses various projects carried out in three major areas of research: applied analysis, computational mathematics, and software engineering. Information on section staff, visitors, workshops, and seminars is found in the appendices.

Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward seeking alternative cathode materials to NiO for molten carbonate fuel cells.

Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) evaluating the dissolution of NiO cathodes in molten carbonate fuel cells and (2) seeking alternative cathode materials. Solubility data were taken for NiO in a cathode environment, and previously operated cells were examined for nickel transfer. A literature search was made for prospective alternative cathode materials, and synthesis of new materials was begun. Apparatus was assembled for conductivity measurements on cathode materials.

Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) improving understanding of component behavior in molten carbonate fuel cells and (2) developing alternative materials and concepts for components. The principal focus was changed during this period from the development of cathodes fabricated from NiO and electrolyte supports of sintered y-LiA102 to an investigation of NiO cathode dissolution and deposition and a search for alternative cathode materials.

Metallic corrosion is one of the major impediments to using the large amounts of heat available in flue and exhaust gases. Our approach is to develop plastic coatings to eliminate this corrosion problem and make this waste heat available economically. The advantages of plastics and their limitations in this application are discussed. Laboratory testing in an acid-condensing environment has been performed on numerous plastics and has identified several plastics with good potential as corrosion barriers. Polyphenylene sulfide, in particular, has resisted sulfuric acid attack for over 5000 hours and can be used at temperatures up to 300 C.

Measurements of the optical properties of metallic aluminum are reviewed and available data are analyzed to obtain the bulk values of the optical constants and the complex dielectric function from 0.04 eV to 10 keV. The intra- and interband contributions to the dielectric function are discussed briefly, and recently proposed values for the Drude parameters describing the intraband absorption are critically considered. Factors influencing experimental measurements are discussed with emphasis on sample properties such as surface oxide layers, bulk inclusion of gases, surface roughness, and degree of crystallinity. The results of recent optical measurements are tabulated, along with recommended values of the optical properties resulting from a self-consistent Kramers-Kronig analysis of reflectance, transmission, and electron-energy-loss studies. The tabular data include the complex dielectric function, the complex index of refraction, and the reflectance and phase shift for normal incidence on a smooth, oxide-free surface. Detailed tabulations are given for the infrared, visible, and ultraviolet regions of the spectrum.

Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to molecular physics and chemistry.

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.

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.

The need to understand concrete behavior under high temperatures in the nuclear industry has become rather acute. For this purpose, a constitutive model of concrete especially developed for this severe environment is indispensable. This report reviews the presently available constitutive models of concrete at standard-temperature conditions and considers their advantages and drawbacks. A rather simple but effective approach is selected to treat concrete behavior at high temperatures. Special emphasis is devoted to the modeling of concrete up to and including failure. The derived constitutive model is checked with biaxial and triaxial benchmark experimental results. Very good agreement is obtained.

REBUS-3 is a system of programs designed for the fuel-cycle analysis of fast reactors. This new capability is an extension and refinement of the REBUS-3 code system and complies with the standard code practices and interface dataset specifications of the Committee on Computer Code Coordination (CCCC). The new code is hence divorced from the earlier ARC System. In addition, the coding has been designed to enhance code exportability. >Major new capabilities not available in the REBUS-2 code system include a search on burn cycle time to achieve a specified value for the multiplication constant at the end of the burn step; a general non-repetitive fuel-management capability including temporary out-of-core fuel storage, loading of fresh fuel, and subsequent retrieval and reloading of fuel; significantly expanded user input checking; expanded output edits; provision of prestored burnup chains to simplify user input; option of fixed-or free-field BCD input formats; and, choice of finite difference, nodal or spatial flux-synthesis neutronics in one-, two-, or three-dimensions.

Waste forms of hydrogen-3, iodine-129, carbon-14, and krypton-85 separated from fuel reprocessing streams and procedures for managing them were analyzed regarding compliance with regulations. Transportation of these wastes in certain DOT-specification packagings would be permissible, but some of these packagings may not be acceptable in some disposal situations. Transportation of gaseous krypton-85 in a currently certified cylinder is possible, but a fuel reprocessor may wish to ship larger quantities per package. Disposal of tritium using a package designed by a DOE contractor and shallow land burial, in accord with the regulations of 10 CFR 61, seems practicable. Although 10 CFR 61 permits shallow land burial of iodine-129, the concentration limit requires distribution in a volume that may seem impractical to commercial fuel reprocessors. The concentration limit of 10 CFR 61 for shallow land burial of carbon-14 requires distribution in a lesser, although still large, volume. For both iodine-129 and carbon-14, management as high-level waste offers the advantage of smaller volumes. Similar advantages may be offered by greater confinement or non-near surface concepts for disposal. The concrete waste forms developed for these nuclides may not meet technical criteria being formulated for geologic disposal. The lack of accommodation of krypton-85 at disposal …