Effects of crack geometry and material behavior on scattering by cracks for QNDE applications (open access)

Effects of crack geometry and material behavior on scattering by cracks for QNDE applications

In work carried out on this project, the usual mathematical modeling of ultrasonic wave scattering by flaws is being extended to account for several typical characteristics of fatigue and stress-corrosion cracks, and the environment of such cracks. Work has been completed on scattering by macrocrack-microcrack configurations. We have also investigated reflection and transmission by a flaw plane consisting of an infinite array of randomly oriented cracks. In another investigation the propagation of mechanical disturbances in solids with periodically distributed cracks has been studied.
Date: September 15, 1989
Creator: Achenbach, J. D.
System: The UNT Digital Library
Effects of crack geometry and material behavior on scattering by cracks for QNDE applications. Technical progress report, March 1, 1988--August 30, 1989 (open access)

Effects of crack geometry and material behavior on scattering by cracks for QNDE applications. Technical progress report, March 1, 1988--August 30, 1989

In work carried out on this project, the usual mathematical modeling of ultrasonic wave scattering by flaws is being extended to account for several typical characteristics of fatigue and stress-corrosion cracks, and the environment of such cracks. Work has been completed on scattering by macrocrack-microcrack configurations. We have also investigated reflection and transmission by a flaw plane consisting of an infinite array of randomly oriented cracks. In another investigation the propagation of mechanical disturbances in solids with periodically distributed cracks has been studied.
Date: September 15, 1989
Creator: Achenbach, J. D.
System: The UNT Digital Library
An investigation of bridge width measurement and processing capabilities (1985) (open access)

An investigation of bridge width measurement and processing capabilities (1985)

An investigation of Mound`s ability to measure and process bridges was conducted in 1985. Prior to improvements in the measuring system and technique, bridge width was found to have a sigma of 0.00019 in. After improvements were made, a sigma of 0.000047 was realized. Bridge length was found to be more erratic than width, although most of the inaccuracy was caused by measurement uncertainty. Length and width were found to have little or no correlation.
Date: May 15, 1989
Creator: Armstrong, K.P.
System: The UNT Digital Library
Configuring the SLC linac for injection into PEP (open access)

Configuring the SLC linac for injection into PEP

From time to time the normal SLC physics program is to be interrupted so that beam can be delivered to PEP. In order that the switch to PEP injection (and the switch back again) can be accomplished quickly and easily, the gun, the damping rings, the linac phase ramp, the energy profile of the linac klystrons for the scavenger bunch, and the entire positron production system are to be kept the same as in the SLC configuration. What mainly remains to be changed is the linac klystron profile for the leading two bunches - those going to PEP. The new klystron profile must be such that it leaves these two beams (1) with final energies that match that of the storage ring and (2) with final energy spectra that fit within the energy aperture of the PEP transfer line. The conditions that need to be met in order to achieve these two goals are discussed in this note. 1 ref., 2 figs.
Date: December 15, 1989
Creator: Bane, K.L.F.
System: The UNT Digital Library
Induction accelerators and free-electron lasers at LLNL: Beam Research Program (open access)

Induction accelerators and free-electron lasers at LLNL: Beam Research Program

Linear induction accelerators have been developed to produce pulses of charged particles at voltages exceeding the capabilities of single-stage, diode-type accelerators and at currents too high rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multistage induction machine. The advent of magnetic pulse power systems makes sustained operation at high repetition rates practical, and high-average-power capability is very likely to open up many new applications of induction machines. In Part A of this paper, we survey the US induction linac technology, emphasizing electron machines. We also give a simplified description of how induction machines couple energy to the electron beam to illustrate many general issues that designers of high-brightness and high-average-power induction linacs must consider. We give an example of the application of induction accelerator technology to the relativistic klystron, a power source for high-gradient accelerators. In Part B we address the application of LIAs to free-electron lasers. The multikiloampere peak currents available from linear induction accelerators make high-gain, free-electron laser amplifier configurations feasible. High extraction efficiencies in a single mass of the electron beam are possible if the wiggler parameters are appropriately ''tapered'', as recently demonstrated at millimeter wavelengths on the 4-MeV ELF …
Date: February 15, 1989
Creator: Briggs, R. J.
System: The UNT Digital Library
A note on thermal analysis for an inclined plate crotch absorber (open access)

A note on thermal analysis for an inclined plate crotch absorber

Crotch absorbers are used to absorb unwanted synchrotron radiation to prevent most of the photons from striking the wall of a vacuum chamber. Since synchrotron radiation generated by bending the positron beam is very powerful, concentrated and penetrating, the absorber produces high internal heat generation. Depending on the materials used, this energy generation may be restricted near the surface of the absorber or distributed throughout the absorber with exponential decay in the direction of the penetration. The cooling of an absorber is important to prevent melting the material and to retain ultra high vacuum, since photon energy deposition on the metal surface causes the desorption of gases. This note describes an analytical solution of the heat transfer with application to designing a crotch absorber. The effects of angles and thicknesses of the plate and different materials on temperature distributions of the absorber are examined.
Date: June 15, 1989
Creator: Choi, M.
System: The UNT Digital Library
Linear plasma-based tritium production facility (open access)

Linear plasma-based tritium production facility

The concept presented here is an adaptation of a recently completed conceptual design of a compact high-fluence D-T neutron source for accelerated end-of-life testing of fusion reactor materials. Although this preliminary assessment serves to illustrate the main features of a linear plasma-based tritium breeder, it is not necessarily an optimized design. We believe that proper design choices for the breeder application will certainly reduce costs, perhaps as much as a factor of two. We also point out that Q (the ratio of fusion power produced to power input to the plasma) increases with system length and that the cost per kg of tritium decreases for longer systems with higher output. In earlier studies of linear two-component plasma systems, Q values as high as three were predicted. At this level of performance and with energy recovery, operating power requirements of the breeder could approach zero. 5 refs., 1 fig., 1 tab.
Date: February 15, 1989
Creator: Coensgen, F. H.; Futch, A. H. & Molvik, A. W.
System: The UNT Digital Library
Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report (open access)

Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report

A Polonium metabolic model was derived and incorporated into a Fortran algorithm which estimates the systemic radiation dose from {sup 210}Po when applied to occupational urine bioassay data. The significance of the doses estimated are examined by defining the degree of uncertainty attached to them through comprehensive statistical testing procedures. Many parameters necessary for dosimetry calculations (such as organ partition coefficients and excretion fractions), were evaluated from metabolic studies of {sup 210}Po in non-human primates. Two tamarins and six baboons were injected intravenously with {sup 210}Po citrate. Excreta and blood samples were collected. Five of the baboons were sacrificed at times ranging from 1 day to 3 months post exposure. Complete necropsies were performed and all excreta and the majority of all skeletal and tissue samples were analyzed radiochemically for their {sup 210}Po content. The {sup 210}Po excretion rate in the baboon was more rapid than in the tamarin. The biological half-time of {sup 210}Po excretion in the baboon was approximately 15 days while in the tamarin, the {sup 210}Po excretion rate was in close agreement with the 50 day biological half-time predicted by ICRP 30. Excretion fractions of {sup 210}Po in the non-human primates were found to be markedly …
Date: March 15, 1989
Creator: Cohen, N.
System: The UNT Digital Library
Conceptual design report for a superconducting coil suitable for use in the large solenoid detector at the SSC (Superconducting Super Collider) (open access)

Conceptual design report for a superconducting coil suitable for use in the large solenoid detector at the SSC (Superconducting Super Collider)

The conceptual design of a large superconducting solenoid suitable for a magnetic detector at the Superconducting Super Collider (SSC) was done at Fermilab. The magnet will provide a magnetic field of 1.7 T over a volume 8 m in diameter by 16 m long. The particle-physics calorimetry will be inside the field volume and so the coil will be bath cooled and cryostable; the vessels will be stainless steel. Predictability of performance and the ability to safely negotiate all probable failure modes, including a quench, are important items of the design philosophy. Our conceptual design of the magnet and calorimeter has convinced us that this magnet is a reasonable extrapolation of present technology and is therefore feasible. The principal difficulties anticipated are those associated with the very large physical dimensions and stored energy of the magnet. 5 figs.
Date: September 15, 1989
Creator: Fast, R.W.; Grimson, J.H.; Krebs, H.J.; Kephart, R.D.; Theriot, D. & Wands, R.H.
System: The UNT Digital Library
Energy changes in transforming solids. Continuation proposal for the period January 1--December 31, 1990 (open access)

Energy changes in transforming solids. Continuation proposal for the period January 1--December 31, 1990

This report describes work completed, work in progress, and work planned during the continuation of funding. Research is being carried out on the following: bonded inclusions are being treated as problems of a homogeneous body; the problem of two cavities or inclusions is being studied; the examination of non-classical transformations is leading to conservation laws in statics and dynamics with applications in fracture and defect mechanics; mathematical and physical modeling of damage in brittle solids is being performed; a theoretical and numerical study of subsonic interfacial waves in bonded piezoelectric dissimilar half-spaces has been completed; the study of which crystal classes are capable of admitting the so-called Type 3 transonic state in anisotropic elasticity is also complete; and wave studies will be extended into the supersonic regime. The authors also intend to complete a study of the general self-force on a 3-dimensional dislocation loop element in an elastic medium of arbitrary anisotropy, as this is currently a needed ingredient in modern fracture and damage mechanics and in the study of defects in integrated circuit materials.
Date: September 15, 1989
Creator: Herrmann, G. & Barnett, D.M.
System: The UNT Digital Library
Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR (open access)

Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR

This report describes the Action Plan for the upgrade of the Chapter 15 Accident Analysis in the SRS Production Reactor SAR required for K-Restart. This Action Plan will be updated periodically to reflect task accomplishments and issue resolutions.
Date: November 15, 1989
Creator: Hightower, N. T., III & Burnett, T. W.
System: The UNT Digital Library
Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR (open access)

Action Plan for updated Chapter 15 Accident Analysis in the SRS Production Reactor SAR

This report describes the Action Plan for the upgrade of the Chapter 15 Accident Analysis in the SRS Production Reactor SAR required for K-Restart. This Action Plan will be updated periodically to reflect task accomplishments and issue resolutions.
Date: November 15, 1989
Creator: Hightower, N. T., III & Burnett, T. W.
System: The UNT Digital Library
Colloid migration in fractured media (open access)

Colloid migration in fractured media

Field studies at the Nevada Test Site by researchers at Lawrence Livermore National Laboratory have demonstrated that radionuclides are being transported by colloidal material suspended in groundwater. This observation is counter to most predictions from contaminant transport models because the models assume adsorbed species are immobile. The purpose of this research is to quantify the transport processes for colloidal materials and develop the mechanistic understanding necessary to predict radionuclide transport in fractured media. There were three areas of investigation during this year that have addressed these issues: chemical control of colloid deposition on clean mineral surfaces, colloid accumulation on fracture surfaces, and the influence of deposited colloids on colloid and tracer migration. 7 refs.
Date: September 15, 1989
Creator: Hunt, J.R. (California Univ., Berkeley, CA (USA). Dept. of Civil Engineering)
System: The UNT Digital Library
Enhancing nuclear power plant performance through the use of artifical intelligence (open access)

Enhancing nuclear power plant performance through the use of artifical intelligence

In the summer of 1988, the Department of Nuclear Engineering (NE) at the University of Tennessee (UT) in Knoxville was selected to carry out a research program in Enhancing the Operation of Nuclear Power plants through the use of Artificial Intelligence, This program is sponsored by the Department of Energy's Office of Energy Research under 10CFR605 for Nuclear Engineering Research. The objective of the research is to advance the state-of-the-art of nuclear power plant control, safety, management, and instrumentation systems through the use of artificial intelligence (AI) techniques, including both expert systems and neural networks. The emphasis will be placed on methods that can be implemented on a rapid or real-time basis. A second, but equally important, objective is to build a broadly based critical mass of expertise in the artificial intelligence, field that can be brought to bear on the technology of nuclear power plants. Both of these goals are being met. This overview and the attached technical reports describe the work that is being carried out. Although in some cases, the scope of the work differs somewhat from the specific tasks described in the original proposal, all activities are clearly within the overall scope of the contract.
Date: June 15, 1989
Creator: Johnson, M.; Maren, A.; Miller, L.; Uhrig, R. & Upadhyaya, B.
System: The UNT Digital Library
Enhancing nuclear power plant performance through the use of artifical intelligence. First annual report (open access)

Enhancing nuclear power plant performance through the use of artifical intelligence. First annual report

In the summer of 1988, the Department of Nuclear Engineering (NE) at the University of Tennessee (UT) in Knoxville was selected to carry out a research program in ``Enhancing the Operation of Nuclear Power plants through the use of Artificial Intelligence, This program is sponsored by the Department of Energy`s Office of Energy Research under 10CFR605 for Nuclear Engineering Research. The objective of the research is to advance the state-of-the-art of nuclear power plant control, safety, management, and instrumentation systems through the use of artificial intelligence (AI) techniques, including both expert systems and neural networks. The emphasis will be placed on methods that can be implemented on a rapid or real-time basis. A second, but equally important, objective is to build a broadly based critical mass of expertise in the artificial intelligence, field that can be brought to bear on the technology of nuclear power plants. Both of these goals are being met. This overview and the attached technical reports describe the work that is being carried out. Although in some cases, the scope of the work differs somewhat from the specific tasks described in the original proposal, all activities are clearly within the overall scope of the contract.
Date: June 15, 1989
Creator: Johnson, M.; Maren, A.; Miller, L.; Uhrig, R. & Upadhyaya, B.
System: The UNT Digital Library
Underestimation of oxygen deficiency hazard through use of linearized temperature profiles (open access)

Underestimation of oxygen deficiency hazard through use of linearized temperature profiles

The failure mode analysis for any cryogenic system includes the effects of a large liquid spill due to vessel rupture or overfilling. The Oxygen Deficiency Hazard (ODH) analysis for this event is a strong function of the estimated heat flux entering the spilled liquid. A common method for estimating the heat flux is to treat the surface on which the liquid spills as a semi-infinite solid. This note addresses the effect of linearizing the temperature profile in this form of analysis, and shows it to cause the calculated flux to be underestimated by more than a factor of two. 3 refs., 2 figs.
Date: June 15, 1989
Creator: Kerby, J.
System: The UNT Digital Library
Materials for ultra-high vacuum (open access)

Materials for ultra-high vacuum

This report discusses materials for use in ultrahigh vacuum systems of 1 {times} 10{sup {minus}9} Torr or lower. The author briefly discusses alloys, solders, insulators and joining methods for vacuum systems. (JDL)
Date: August 15, 1989
Creator: Lee, G.
System: The UNT Digital Library
Molecular biological enhancement of coal biodesulfurization. First quarterly technical progress report (open access)

Molecular biological enhancement of coal biodesulfurization. First quarterly technical progress report

The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: Clone and characterize the genes encoding the enzymes of the ``4S`` pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; transfer this pathway into a fast-growing chemolithotropic bacterium; conduct a batch-mode optimization/analysis of scale-up variables.
Date: September 15, 1989
Creator: Litchfield, J. H.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N.
System: The UNT Digital Library
Molecular biological enhancement of coal biodesulfurization. [Rhodococcus] (open access)

Molecular biological enhancement of coal biodesulfurization. [Rhodococcus]

The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: Clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; transfer this pathway into a fast-growing chemolithotropic bacterium; conduct a batch-mode optimization/analysis of scale-up variables.
Date: September 15, 1989
Creator: Litchfield, J. H.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N. (Battelle, Columbus, OH (United States))
System: The UNT Digital Library
Final summary report for 1989 inservice inspection (ISI) of SRS (Savannah River Site) 100-P Reactor tank (open access)

Final summary report for 1989 inservice inspection (ISI) of SRS (Savannah River Site) 100-P Reactor tank

The integrity of the SRS reactor tanks is a key factor affecting their suitability for continued service since, unlike the external piping system and components, the tanks are virtually irreplaceable. Cracking in various areas of the process water piping systems has occurred beginning in 1960 as a result of several degradation mechanisms, chiefly intergranular stress corrosion cracking (IGSCC) and chloride-induced transgranular cracking. IGSCC, currently the primary degradation mechanism, also occurred in the knuckle'' region (tank wall-to-bottom tube sheet transition piece) unique to C Reactor and was eventually responsible for that reactor being deactivated in 1985. A program of visual examinations of the SRS reactor tanks was initiated in 1968, which used a specially designed immersible periscope. Under that program the condition of the accessible tank welds and associated heat affected zones (HAZ) was evaluated on a five-year frequency. Prior to 1986, the scope of these inspections comprised approximately 20 percent of the accessible weld area. In late 1986 and early 1987 the scope of the inspections was expanded and a 100 percent visual inspection of accessible welds was performed of the P-, L-, and K-Reactor tanks. Supplemental dye penetrant examinations were performed in L Reactor on selected areas which showed …
Date: December 15, 1989
Creator: Morrison, J. M. & Loibl, M. W.
System: The UNT Digital Library
Transport properties of multi-component fluids and of suspensions (open access)

Transport properties of multi-component fluids and of suspensions

This report describes work performed under grant No. DE-FG03-88ER13911 for the period June 15, 1988 through June 14, 1989. During this time, significant progress was made in the derivation of the fundamental equations describing suspensions and multicomponent fluid flow. We first considered a system consisting of spherical heavy (Brownian) particles immersed in a bath of spherical particles. The deviations of the bath from equilibrium are due to the nonequilibrium motions of the Brownian particles. The densities of the bath and of a Brownian particle are similar. An expansion in powers of the mass ratio, yields a Fokker-Planck equation for the distribution function of the Brownian particles, including the effects of direct and hydrodynamic interactions amongst these particles. The effect of the Brownian particle motion on the bath properties has been described. The conditions under which a closed equation for the coordinate space distribution function, can be obtained have been investigated and a Smoluchowski equation for this quantity has been derived.
Date: September 15, 1989
Creator: Oppenheim, I. & McBride, J.
System: The UNT Digital Library
Transport properties of multi-component fluids and of suspensions. Annual progress report, June 15, 1988--June 14, 1989 (open access)

Transport properties of multi-component fluids and of suspensions. Annual progress report, June 15, 1988--June 14, 1989

This report describes work performed under grant No. DE-FG03-88ER13911 for the period June 15, 1988 through June 14, 1989. During this time, significant progress was made in the derivation of the fundamental equations describing suspensions and multicomponent fluid flow. We first considered a system consisting of spherical heavy (Brownian) particles immersed in a bath of spherical particles. The deviations of the bath from equilibrium are due to the nonequilibrium motions of the Brownian particles. The densities of the bath and of a Brownian particle are similar. An expansion in powers of the mass ratio, yields a Fokker-Planck equation for the distribution function of the Brownian particles, including the effects of direct and hydrodynamic interactions amongst these particles. The effect of the Brownian particle motion on the bath properties has been described. The conditions under which a closed equation for the coordinate space distribution function, can be obtained have been investigated and a Smoluchowski equation for this quantity has been derived.
Date: September 15, 1989
Creator: Oppenheim, I. & McBride, J.
System: The UNT Digital Library
Phase behavior of coal fluids: Data for correlation development (open access)

Phase behavior of coal fluids: Data for correlation development

During the present report period, our framework for correlating saturation properties using the scaled-variable-reduced coordinate approach was used to develop a correlation for saturated liquid densities of pure fluids at temperatures from the triple point to the critical point. The new correlation results in precise representation of liquid densities of diverse chemical species with average errors of 0.12% when two adjustable parameters are used to characterize each substance. In addition, the proposed model compares favorably with the modified Rackett and the Hankinson-Thomson correlations with the added advantages of covering the full saturation range and obeying scaling-law behavior in the near-critical region. Although the approach is essentially empirical, the results obtained suggest an underlying physical significance for the model parameters and show an excellent potential for generalized predictions. This is demonstrated by the results given here for saturated liquid densities where fully generalized predictions yield average errors of less than 1.0%.
Date: October 15, 1989
Creator: Robinson, R. L. Jr.; Gasem, K. A. M. & Shaver, R. D.
System: The UNT Digital Library
Phase behavior of coal fluids: Data for correlation development. Report period: August 15, 1989--October 15, 1989 (open access)

Phase behavior of coal fluids: Data for correlation development. Report period: August 15, 1989--October 15, 1989

During the present report period, our framework for correlating saturation properties using the scaled-variable-reduced coordinate approach was used to develop a correlation for saturated liquid densities of pure fluids at temperatures from the triple point to the critical point. The new correlation results in precise representation of liquid densities of diverse chemical species with average errors of 0.12% when two adjustable parameters are used to characterize each substance. In addition, the proposed model compares favorably with the modified Rackett and the Hankinson-Thomson correlations with the added advantages of covering the full saturation range and obeying scaling-law behavior in the near-critical region. Although the approach is essentially empirical, the results obtained suggest an underlying physical significance for the model parameters and show an excellent potential for generalized predictions. This is demonstrated by the results given here for saturated liquid densities where fully generalized predictions yield average errors of less than 1.0%.
Date: October 15, 1989
Creator: Robinson, R. L. Jr.; Gasem, K. A. M. & Shaver, R. D.
System: The UNT Digital Library