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Assessment of light water reactor fuel damage during a reactivity initiated accident

Description: This paper presents an assessment of LWR fuel damage during a reactivity initiated accident and comments on the adequacy of the present USNRC design requirements. Results from early SPERT tests are reviewed and compared with results from recent computer simulations and PBF tests. A progression of fuel rod and cladding damage events is presented. High strain rate deformation of relatively cool irradiated cladding early in the transient may result in fracture at a radial average peak fuel enthalp… more
Date: January 1, 1980
Creator: MacDonald, P. E.; Seiffert, S. L.; Martinson, Z. R.; McCardell, R. K.; Owen, D. E. & Fukuda, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-ray measurements of stresses and defects in EFG and large grained polycrystalline silicon ribbons. First quarterly report

Description: The first model of a modified Bond goniometer has been built and tested for the precision measurement of interplanar spacings in Si-single crystals. A change in interplanar spacing ..delta..d/d approximately = to +- 10/sup -5/ can be detected which corresponds to surface stresses of the order of +- 1000 psi. A second version of the goniometer is being assembled incorporating a removable microscope for precision alignment of the Si-strip into the primary X-ray beam.
Date: January 1, 1978
Creator: Wagner, C.N.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Repair Welding of Fusion Reactor Components

Description: Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state … more
Date: May 20, 1992
Creator: Chin, Bryan A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of an extended-burnup Mark B design. First semi-annual progress report, July-December 1978. Report BAW-1532-1. [PWR]

Description: The primary objective of this program is to develop and demonstrate an improved PWR fuel assembly design capable of batch average burnups of 45,000-50,000 MWd/mtU. To accomplish this, a number of technical areas must be investigated to verify acceptable extended-burnup fuel performance. This report is the first semi-annual progress report for the program, and it describes work performed during the July-December 1978 time period. Efforts during this period included the definition of a preliminar… more
Date: October 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of flow curvature on the aerodynamics of Darrieus wind turbines

Description: A theoretical and experimental investigation was conducted which clearly showed the effects of flow curvature to be significant determinants of Darrieus turbine blade aerodynamics; qualitatively, these results apply equally to straight or curved bladed machines. Unusually large boundary layer radial pressure gradients and virtually altered camber and incidence are the phenomena of primary importance. Conformal mapping techniques were developed which transform the geometric turbine airfoils in c… more
Date: July 1, 1980
Creator: Migliore, P. G. & Wolfe, W. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The rate dependence of the saturation flow stress of Cu and 1100 Al

Description: The strain-rate dependence of the saturation flow stress of OFHC Cu and 1100 Al from 10{sup {minus}3}s{sup {minus}1} to nearly to 10{sup 12}s{sup {minus}1} is examined. The flow stress above 10{sup 9}s{sup {minus}1} is estimated using Wallace's theory of overdriven shocks in metals. A transition to the power-law behavior {Psi} {approximately} {tau}{sub s}{sup 5} occurs at a strain rate of order 10{sup 5}s{sup {minus}1}. 10 refs., 2 figs.
Date: January 1, 1991
Creator: Preston, D.L.; Tonks, D.L. & Wallace, D.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

PNL technical review of pressurized thermal-shock issues. [PWR]

Description: Pacific Northwest Laboratory (PNL) was asked to develop and recommend a regulatory position that the Nuclear Regulatory Commission (NRC) should adopt regarding the ability of reactor pressure vessels to withstand the effects of pressurized thermal shock (PTS). Licensees of eight pressurized water reactors provided NRC with estimates of remaining effective full power years before corrective actions would be required to prevent an unsafe operating condition. PNL reviewed these responses and the r… more
Date: July 1, 1982
Creator: Pedersen, L. T.; Apley, W. J.; Bian, S. H.; Defferding, L. J.; Morgenstern, M. H.; Pelto, P. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Inelastic processes in seismic wave generation by underground explosions

Description: Theories, computer calculations, and measurements of spherical stress waves from explosions are described and compared, with emphasis on the transition from inelastic to almost-elastic relations between stress and strain. Two aspects of nonspherical explosion geometry are considered: tectonic strain release and surface spall. Tectonic strain release affects the generation of surface waves; spall closure may also. The reduced-displacement potential is a common solution (the equivalent elastic so… more
Date: August 1, 1980
Creator: Rodean, H.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Solder fatigue reduction in point focus photovoltaic concentrator modules

Description: Solder fatigue tests have been conducted on point focus photovoltaic concentration cell assemblies to identify a baseline fatigue life and to quantify the fatigue life improvements that result using a copper-molybdenum-copper low-expansion insert between the solar cell and copper heat spreader. Solder microstructural changes and fatigue crack growth were identified using cross sections and ultrasonic scans of the fatigue solder joints. The Coffin-Manson and Total Strain fatigue models for low-c… more
Date: January 1, 1991
Creator: Hund, T. D. & Burchett, S. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CHILES 2: a finite element computer program that calculates the intensities of linear elastic singularities in isotropic and orthotropic materials

Description: CHILES 2 is a finite-element computer program that calculates the strength of singularities in linear elastic bodies. A generalized quadrilateral finite element that includes a singular point at a corner node is incorporated in the code. The displacement formulation is used and interelement compatibility is maintained so that monotone convergence is preserved. Plane stress, plane strain, and axisymmetric conditions are treated. Isotropic and orthotropic crack tip singularity problems are solved… more
Date: February 1, 1978
Creator: Benzley, S.E. & Beisinger, Z.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume IV. Receiver subsystem. [10-MW Pilot Plant and 100-MW Commercial Plant]

Description: The conception, design, and testing of the receiver subsystem proposed by the McDonnell Douglas/Rocketdyne Receiver team for the DOE 10-MW Pilot Plant and the 100-MW Commercial Plant are described. The receiver subsystem consists of the receiver unit, the tower on which the receiver unit is mounted above the collector field, and the supporting control and instrumentation equipment. The plans for implementation of the Pilot Plant are given including the anticipated schedule and production plan (… more
Date: November 1, 1977
Creator: Hallet, Jr., R. W. & Gervais, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Scoping Experiments for a Space Reactor

Description: Some scoping experiments were performed to evaluate fuel performance in a lithium heat pipe reactor operating at a nominal 1500K heat pipe temperature. Fuel-coolant and fuel-coolant-clad relationships showed that once a failed heat pipe occurs temperatures can rise high enough so that large concentrations of uranium can be transported by the vapor phase. Upon condensation this uranium would be capable of penetrating heat pipes adjacent to the failed pipe. The potential for propagation of failur… more
Date: July 7, 1983
Creator: Alexander, C. A. & Ogden, J. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computing the effect of plastic deformation of piping on pressure transient propagation. [LMFBR]

Description: The computer program PTA-1 performs pressure-transient analysis of large piping networks using the one-dimensional method of characteristics applied to a fluid-hammer formulation. The effect of elastic-plastic deformation of piping on pulse propagation is included in the computation. Each pipe is modeled as a series of rings, neglecting axial effects, bending moments, and inertia. The fluid wave speed is a function of pipe deformation and, consequently, of position and time. Comparison with exi… more
Date: January 1, 1977
Creator: Youngdahl, C.K. & Kot, C.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Torque ripple in a Darrieus, vertical axis wind turbine

Description: Interaction between a steady wind and a rotating, Darrieus, vertical axis wind turbine produces time periodic aerodynamic loads which cause time dependent torque variations, referred to as torque ripple, to occur in the mechanical link between the turbine and the electrical generator. There is concern for the effect of torque ripple upon fatigue life of drive train components and upon power quality. An analytical solution characterizing the phenomenon of torque ripple has been obtained which is… more
Date: January 1, 1980
Creator: Reuter, R.C. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1980-March 31, 1980

Description: Results are presented of work performed on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical prope… more
Date: June 25, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Criterion for quasibrittle crack growth

Description: An expression to predict the onset of growth of a crack in a quasibrittle material is derived. An energy criterion essentially equivalent to the first two laws of thermodynamics is employed. The criterion is applied to the elastic-plastic crack of Olesiak and Wnuk (1968). 12 references, 3 figures. (ACR)
Date: January 1, 1984
Creator: Margolin, L.G. & Smith, B.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal strains in titanium aluminide and nickel aluminide composites

Description: Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more
Date: January 1, 1992
Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calibration of a Hopkinson bar with a transfer standard

Description: During the past year, program field test temperatures, that are beyond the test accelerometer operational limits of {minus}30{degrees}F and +150{degrees}F, required the calibration of accelerometers at high shock levels and at the temperature extremes of {minus}50{degrees}F and +160{degrees}F. The purposes of these calibrations were to insure the accelerometers operated at the field test temperatures and to provide an accelerometer sensitivity at each test temperature. Since there is no NIST-tr… more
Date: January 1, 1991
Creator: Bateman, V. I.; Leisher, W. B.; Brown, F. A. & Davie, N. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Seismic Safety Margins Research Program. Phase 1. Project V. Structural sub-system response: subsystem response review. [PWR; BWR]

Description: This project is directed toward a portion of the Seismic Safety Margins Research Program which includes one link in the seismic methodology chain. The link addressed here is the structural subsystem dynamic response which consists of those components and systems whose behavior is often determined decoupled from the major structural response. Typically the mathematical model utilized for the major structural response will include only the mass effects of the subsystem and the main model is used … more
Date: March 1, 1980
Creator: Fogelquist, J.; Kaul, M.K.; Koppe, R.; Tagart, S.W. Jr.; Thailer, H. & Uffer, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanical compaction of Waste Isolation Pilot Plant simulated waste

Description: The investigation described in this report acquired experimental information about how materials simulating transuranic (TRU) waste compact under axial compressive stress, and used these data to define a model for use in the Waste Isolation Pilot Plant (WIPP) disposal room analyses. The first step was to determine compaction curves for various simultant materials characteristic of TRU waste. Stress-volume compaction curves for various combinations of these materials were than derived to represe… more
Date: June 1, 1991
Creator: Butcher, B. M.; Thompson, T. W.; VanBuskirk, R. G. & Patti, N. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Seismic velocities and attenuation in an underground granitic waste repository subjected to heating

Description: The behavior of a granitic rock mass subjected to thermal load has been studied by an acoustic cross-hole technique between four boreholes, over a period of some two years. Velocities between boreholes were obtained from the times-of-flight of pulses of acoustic waves between transducers clamped to the borehole wall. The attenuation was obtained by a spectral ratios technique. When the heater was turned on, the velocities increased rapidly to an asymptotic value. When the heater was turned off,… more
Date: March 1, 1984
Creator: Paulsson, B.N.P. & King, M.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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