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3-D field computations for accelerator magnets using finite element and integral codes (open access)

3-D field computations for accelerator magnets using finite element and integral codes

Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960`s, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: December 1, 1992
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
System: The UNT Digital Library
The 400 MeV Linac Upgrade at Fermilab (open access)

The 400 MeV Linac Upgrade at Fermilab

The Fermilab Linac Upgrade in planned to increase the energy of the H[sup [minus]] linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1, 1992
Creator: Noble, R.J.
System: The UNT Digital Library
The 400 MeV Linac Upgrade at Fermilab (open access)

The 400 MeV Linac Upgrade at Fermilab

The Fermilab Linac Upgrade in planned to increase the energy of the H{sup {minus}} linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1992
Creator: Noble, Robert J.
System: The UNT Digital Library
Absolute total and one and two electron transfer cross sections for Ar{sup 8+} on Ar as a function of energy (open access)

Absolute total and one and two electron transfer cross sections for Ar{sup 8+} on Ar as a function of energy

The absolute total and one and two electron transfer cross sections for Ar{sup 8+} on Ar were measured as a function of projectile laboratory energy from 0.090 to 0.550 keV/amu. The effective one electron transfer cross section dominates above 0.32 keV/amu, while below this energy, the effective two electron transfer starts to become appreciable. The total cross section varies by a factor over the energy range explored. The overall error in the cross section measurement is estimated to be {plus_minus} 15%.
Date: December 31, 1992
Creator: Vancura, J. & Kostroun, V. O.
System: The UNT Digital Library
Accelerated glass reaction under PCT conditions (open access)

Accelerated glass reaction under PCT conditions

Static leach tests similar to PCT (Product Consistency Test) were performed for up to 2 years to assess long-term reaction behavior of high-level nuclear waste glasses similar to those at Defense Waste Processing Facility. These tests show the reaction rate to decrease with the reaction time from an initially high rate to a low rate, but then to accelerate to a higher rate after reaction times of about 1 year, depending on glass surface area/leachant volume ratio used. Solution concentrations of soluble glass components increase as the reaction is accelerated, while release of other glass components into solution is controlled by secondary phases. Net result is that transformation of glass to stable phases is accelerated while the solution becomes enriched in soluble components not effectively contained in secondary phases. Rate becomes linear in time after the acceleration and may be similar to the initial forward rate. A current model of glass reaction predicts that the glass reaction will be accelerated upon the formation of secondary phases which lower the silicic acid solution concentration. These tests show total Si concentration to increase upon reaction acceleration, however, which may be due to the slightly higher pH attained with the acceleration. The sudden …
Date: December 31, 1992
Creator: Ebert, W. L.; Bates, J. K.; Buck, E. C. & Bradley, C. R.
System: The UNT Digital Library
Accident information needs (open access)

Accident information needs

A Five-step methodology has been developed to evaluate information needs for nuclear power plants under accident conditions and the availability of plant instrumentation during severe accidents. Step 1 examines the credible accidents and their relationships to plant safety functions. Step 2 determines the information personnel involved in accident management will need to understand plant behavior. Step 3 determines the capability of the instrumentation to function properly under severe accident conditions. Step 4 determines the conditions expected during the identified severe accidents. Step 5 compares the instrument capabilities and the severe accident conditions to evaluate the availability of the instrumentation to supply needed plant information.
Date: December 31, 1992
Creator: Hanson, D. J.; Arcieri, W. C. & Ward, L. W.
System: The UNT Digital Library
Accrediting industrial safety training programs (open access)

Accrediting industrial safety training programs

There are job-specific training requirements established by regulations that Impose stringent training requirements on a contractor, for example, the Occupational Safety & Health Act (OSHA). Failure to comply with OSHA training requirements can result in severe penalties being levied against a company. Although an accredited training program is expensive, it is a possible solution for minimizing risks associated with job-specific training requirements for employees. Operating DOE contractors direct approximately 10 percent of the operating funds toward training activities. Training needs for contractors span a broad range, from requirements awareness training for managers, to general training required on a one-time basis for all employees, to highly specialized training programs for employees involved In clean-up operations at hazardous waste sites. With this kind of an investment in training, it is logical to maximize the most return on an investment of training funds and to limit exposure to liability suits whenever possible. This presentation will provide an overview of accredited industrial safety programs. The criteria for accredited industrial safety programs will be defined. The question of whether accredited training programs are necessary will be examined. Finally, advantages and disadvantages will be identified for accrediting industrial safety training programs.
Date: December 31, 1992
Creator: Beitel, L.
System: The UNT Digital Library
Activation and deactivation of high concentration arsenic with some evidence of precipitation (open access)

Activation and deactivation of high concentration arsenic with some evidence of precipitation

Using box-shaped profiles created by laser melt annealing, the authors investigate the kinetics of arsenic activation and deactivation. They find deactivation shows no history effects, which can be consistent either with clustering or precipitation for the cases considered. For activation, they notice it occurs on very short time scales, followed by a slower deactivation process. This is suggestive evidence that at least some precipitation occurs.
Date: December 29, 1992
Creator: Rousseau, P. M.; Griffin, P. B.; Plummer, J. D. & Carey, P. G.
System: The UNT Digital Library
Adaptive optics for high power beam lines using diamond crystal monochromators (open access)

Adaptive optics for high power beam lines using diamond crystal monochromators

Preserving the high source brightness of the third generation of synchrotron radiation facilities will require that thermal and pressure deformations of the monochromator crystals be maintained within a few arc- seconds. Recent experiments at the National Synchrotron Light Source (NSLS) have demonstrated the potential of adaptive crystal optics to cope with high power densities. In this technique the crystals deformations are minimized both by an efficient water-jet cooling and by externally applied pressure loads. Thermal deformation can be reduced further with diamond crystals because of their high thermal conductivity and low coefficient of thermal expansion. In this paper we describe the results achieved by optimization of adaptive crystal optics for diamond crystals.
Date: December 31, 1992
Creator: Sharma, S.; Berman, L. E.; Hastings, J. B. & Hart, M.
System: The UNT Digital Library
The ADRIA project for high intensity radioactive beams production (open access)

The ADRIA project for high intensity radioactive beams production

A proposal of an accelerator complex (ADRIA) for the Laboratori Nazionali di Legnaro (LNL) is described in this report. The main components of the complex are a Heavy Ion Injection system and two rings, a Booster and a Decelerator, both with a maximum rigidity of 22.25 Tm, connected by a Transfer Line where exotic proposal has two main goals consisting in the isotopes are produced and selected. The proposal has two main goals consisting in the acceleration of stable ion species up to kinetic energies of the order of few GeV/u, at a repetition rate of 10 Hz with intensities of about 10{sup 12} ions per second, for fixed target experiments in nuclear physics and for the production of fully stripped radioactive beams, using particle fragmentation method for nuclear spectroscopy experiments. Fragments are accumulated in the Decelerator, with intensities 10{sup 8} {divided_by} 10{sup 9} ions/s, cooled and delivered at the production energies or decelerated down to energies of few MeV/u, in proximity of the Coulomb barrier.
Date: December 31, 1992
Creator: Bisoffi, G.; Cavenago, M.; Dainelli, A.; Facco, A.; Fortuna, G.; Lombardi, A. et al.
System: The UNT Digital Library
Advanced Turbine Design Program (open access)

Advanced Turbine Design Program

The prime objective of this project task is to select a natural gas fired as Advanced Turbine Systems (ATS) capable of reaching 60% cycle efficiency. Several cycles were compared and evaluated under all different kind of aspects, to determine the one with the highest potential and, at the same time, the best overall fit within and experience base to guarantee project goals. The combined cycle with multistep development potential was identified as the system to reach the 60% or greater thermal efficiency.
Date: December 31, 1992
Creator: van der Linden, S.; Gnaedig, G. & Kreitmeier, F.
System: The UNT Digital Library
Advanced turbine systems program (open access)

Advanced turbine systems program

In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable …
Date: December 31, 1992
Creator: Wilkes, C.; Mukavetz, D. W.; Knickerbocker, T. K. & Ali, S. A.
System: The UNT Digital Library
Advances in Reversed Field Pinch Theory and Computation (open access)

Advances in Reversed Field Pinch Theory and Computation

Advances in theory and computations related to the reversed field pinch (RFP) are presented. These are: (1) the effect of the dynamo on thermal transport; (2) a theory of ion heating due to dynamo fluctuations; (3) studies of active and passive feedback schemes for controlling dynamo fluctuations; and (4) an analytic model for coupled g-mode and rippling turbulence in the RFP edge.
Date: December 31, 1992
Creator: Schnack, D. D.; Ho, Y. L.; Carreras, B. A.; Sidikman, K.; Craddock, G. G.; Mattor, N. et al.
System: The UNT Digital Library
Allowance trading: Market operations and regulatory response (open access)

Allowance trading: Market operations and regulatory response

The use of the SO{sub 2} allowance system as defined by Title IV of the 1990 Clean Air Act Amendments offers utilities greater compliance flexibility than EPA technology standards, State Implementation Plan (SEP) performance standards, or EPA bubble/offset strategies. Traditional methods at best offered the utility the ability to trade emissions between different units at a particular plant. The SO{sub 2} emissions trading system advocated under Title IV will allow a utility to trade emissions across its utility system, and/or trade emissions between utilities to take advantage of interfirm control cost differences. The use of transferable emission allowances offers utilities greater flexibility in the choice of how to control emissions: the choices include fuel switching, flue gas scrubbing, environmental dispatch, repowering, and even the choice not to control emissions [as long as the New Source Performance Standards (NSPS) and Prevention of Significant Deterioration (PSD) requirements are met]. The added flexibility allows utilities to choose the least cost manner of compliance with Title IV requirements. It is hoped (intended) that pollution control cost-minimization by individual utilities will in turn reduce the cost of controlling SO{sub 2} for the electric utility industry in aggregate. In addition, through the use of NO{sub x} …
Date: December 31, 1992
Creator: Bailey, K. A.; South, D. W. & McDermott, K. A.
System: The UNT Digital Library
Alpha CAM filter particle collection pattern study results (open access)

Alpha CAM filter particle collection pattern study results

During a January 1991 Westinghouse Internal Audit of the WIPP Radiological Air Monitoring Program, an auditor observed that on an Eberline Alpha-6A CAM filter, some particulate was deposited outside the 25 mm diameter area that the filter is planned to use. Since the CAM uses a 25 mm diameter detector, this observation raised concern that the operational efficiency may be affected by the spread of filtrate. A (Eberline Alpha-6A) CAM particle collection pattern study was undertaken to determine if any significant sensitivity loss resulted from the broadened filtrate area and then to determine actions to improve performance if required. The results of this study provide documentation of the filtrate patterns on each of the Eberline Alpha-6A CAMs in use at the WIPP. In addition, data is reported that shows the results of some changes to the CAM sampling system that appear to improve the edge definition of the collected material on the filter. An important conclusion is that the relatively small spread of filtrate is consistent from CAM to CAM and studies by Texas A&M show that the majority of respirable size particles are collected in the center of the 25 mm diameter pattern while the visible particles that were …
Date: December 31, 1992
Creator: Clayton, S. G.; Steinbruegge, K. B. & Merkling, T. D.
System: The UNT Digital Library
Amorphization kinetics of Zr(Cr,Fe){sub 2} under ion irradiation (open access)

Amorphization kinetics of Zr(Cr,Fe){sub 2} under ion irradiation

Thin foils of Zircaloy-4 were irradiated with 350 KeV {sup 40}Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300--650 K. The irradiation-induced amorphization of the intermetallic precipitates Zr (Cr; Fe){sub 2} and Zr{sub 2} (Ni, Fe) was studied in-situ. For Zr (Cr, Fe){sub 2} precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr{sub 2} (Ni,Fe) precipitates it was found that amorphization occurred at 550 and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in context of previous neutron and electron irradiations and likely amorphization mechanisms are proposed.
Date: December 1, 1992
Creator: Motta, A. T.; Howe, L. M. & Okamoto, P. R.
System: The UNT Digital Library
Amorphization kinetics of Zr(Cr,Fe)[sub 2] under ion irradiation (open access)

Amorphization kinetics of Zr(Cr,Fe)[sub 2] under ion irradiation

Thin foils of Zircaloy-4 were irradiated with 350 KeV [sup 40]Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300--650 K. The irradiation-induced amorphization of the intermetallic precipitates Zr (Cr; Fe)[sub 2] and Zr[sub 2] (Ni, Fe) was studied in-situ. For Zr (Cr, Fe)[sub 2] precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr[sub 2] (Ni,Fe) precipitates it was found that amorphization occurred at 550 and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in context of previous neutron and electron irradiations and likely amorphization mechanisms are proposed.
Date: December 1, 1992
Creator: Motta, A.T. (Pennsylvania State Univ., University Park, PA (United States). Dept. of Nuclear Engineering); Howe, L.M. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Labs.) & Okamoto, P.R. (Argonne National Lab., IL (United States))
System: The UNT Digital Library
Analog Signal Isolation Techniques (open access)

Analog Signal Isolation Techniques

This paper discusses several techniques for isolating analog signals in an accelerator environment. The techniques presented here encompass isolation amplifiers, voltage-to-frequency converters (VIFCs), transformers, optocouplers, discrete fiber optics, and commercial fiber optic links. Included within the presentation of each method are the design issues that must be considered when selecting the isolation method for a specific application.
Date: December 31, 1992
Creator: Beadle, Edward R.
System: The UNT Digital Library
Analyses for conversion of the Georgia Tech Research Reactor from HEU to LEU fuel (open access)

Analyses for conversion of the Georgia Tech Research Reactor from HEU to LEU fuel

The 5 MW Georgia Tech Research Reactor (GTRR) is a heterogeneous, heavy water moderated and cooled reactor, fueled with highly-enriched uranium aluminum alloy fuel plates. The GTRR is required to convert to low enrichment (LEU) fuel in accordance with USNRC policy. Results of design and safety analyses performed by the RERTR Program at the Argonne National Laboratory for LEU conversion of the GTRR are summarized. Only those parameters which could change as a result of replacing the fuel are addressed. The performance of the reactor and all safety margins with LEU fuel are expected to be about the same as those with the current HEU fuel.
Date: December 31, 1992
Creator: Matos, J. E.; Mo, S. C. & Woodruff, W. L.
System: The UNT Digital Library
Analysis and correction of noise on electronic circuits in an accelerator environment (open access)

Analysis and correction of noise on electronic circuits in an accelerator environment

Accelerator noise sources can cause both analog and digital electronic circuits to malfunction. This paper identifies and analyzes noise sources, and describes the methodology for measurement. Both general remedies and specific solutions to minimize the noise effects on accelerator electronic circuits are described. A policy for electronic design, board layout, assembly, and fabrication is established. Conclusions are drawn based on theoretical principles with practical examples shown in case studies.
Date: December 1, 1992
Creator: Fathizadeh, M.; Despe, O. D. & McGhee, D. G.
System: The UNT Digital Library
Analysis of a proposed Compton backscatter imaging technique (open access)

Analysis of a proposed Compton backscatter imaging technique

Imaging techniques which require access to only one side of the object being viewed are potentially useful in situations where conventional projection radiography and tomography cannot be applied, such as looking for voids in a large container where access to the back of the object is inconvenient or even impossible. One-sided imaging techniques are currently being used in nondestructive evaluation of surfaces and shallow subsurface structures. In this work we present both analytical calculations and detailed Monte Carlo simulations aimed at assessing the capability of a proposed Compton backscatter imaging technique designed to detect and characterize voids located several centimeters below the surface of a solid. The proposed technique, based on a scheme suggested by Farmer and Collins, encodes the spatial position and structure of voids in a solid in the energy spectrum of the Compton-scattered photons as recorded by a high resolution detector. Our calculations model a {sup 137}Cs source projecting a 1 mm{sup 2} pencil beam of 662 keV gammas into a target slab at an incident angle of 45{degrees} and a collimated detector (also oriented at 45{degrees} with respect to the surface) which views the beam path at a central angle of 90{degrees}. The detector collimator is …
Date: December 1, 1992
Creator: Hall, J. & Jacoby, B.
System: The UNT Digital Library
Analysis of accidents during the mid-loop operating state at a PWR (open access)

Analysis of accidents during the mid-loop operating state at a PWR

Studies suggest that the risk of severe accidents during low power operation and/or shutdown conditions could be a significant fraction of the risk at full power operation. The Nuclear Regulatory Commission has begun two risk studies to evaluate the progression of severe accidents during these conditions: one for the Surry plant, a pressurized water reactor (PWR), and the other for the Grand Gulf plant, a boiling water reactor (BWR). This paper summarizes the approach taken for the Level 2/3 analysis at Surry for one plant operating state (POS) during shutdown. The current efforts are focussed on evaluating the risk when the reactor is at mid-loop; this particular POS was selected because of the reduced water inventory and the possible isolation of the loops. The Level 2/3 analyses are conditional on core damage having occurred. Initial results indicate that the conditional consequences can indeed be significant; the defense-in-depth philosophy governing the safety of nuclear power plants is to some extent circumvented because the containment provides only a vapor barrier with no capability for pressure holding, during this POS at Surry. However, the natural decay of the radionuclide inventory provides some mitigation. There are essentially no predicted offsite prompt fatalities even for …
Date: December 31, 1992
Creator: Jo, J.; Lin, C. C.; Mufayi, V.; Neymotin, L. & Nimnual, S.
System: The UNT Digital Library
Analysis of complex systems using neural networks (open access)

Analysis of complex systems using neural networks

The application of neural networks, alone or in conjunction with other advanced technologies (expert systems, fuzzy logic, and/or genetic algorithms), to some of the problems of complex engineering systems has the potential to enhance the safety, reliability, and operability of these systems. Typically, the measured variables from the systems are analog variables that must be sampled and normalized to expected peak values before they are introduced into neural networks. Often data must be processed to put it into a form more acceptable to the neural network (e.g., a fast Fourier transformation of the time-series data to produce a spectral plot of the data). Specific applications described include: (1) Diagnostics: State of the Plant (2) Hybrid System for Transient Identification, (3) Sensor Validation, (4) Plant-Wide Monitoring, (5) Monitoring of Performance and Efficiency, and (6) Analysis of Vibrations. Although specific examples described deal with nuclear power plants or their subsystems, the techniques described can be applied to a wide variety of complex engineering systems.
Date: December 31, 1992
Creator: Uhrig, R. E.
System: The UNT Digital Library
An analysis of lift forces on aerosols in a wall bounded turbulent shear flow (open access)

An analysis of lift forces on aerosols in a wall bounded turbulent shear flow

This paper describes work that will lead to a better understanding of the role of lift forces in the deposition of aerosols on the walls bounding a turbulent shear flow. After providing some background information about aerosol trajectories that has been obtained from computer simulations, new results for the lift force in the relevant parameter ranges are presented.
Date: December 31, 1992
Creator: Cherukat, P. & McLaughlin, J. B.
System: The UNT Digital Library