Characterization techniques for high quality ICF targets (open access)

Characterization techniques for high quality ICF targets

To avoid the effects of fluid instabilities, stringent requirements must be imposed on the surface quality and wall thickness uniformity of fuel pellets used in Inertial Confinement Fusion compression experiments. A systematic method was developed for specifying the type of defects which must be avoided and for evaluating measurement techniques for their suitability for detecting these defects. A review is given of the techniques currently available and those under development to show the relationship between these capabilities and the current and future requirements for pellet uniformity. The speed of these techniques and the implications for automated production of fuel pellets for a reactor are discussed.
Date: March 23, 1979
Creator: Weinstein, B.W. & Hendricks, C.D.
System: The UNT Digital Library
Decontamination methods (open access)

Decontamination methods

This paper discusses decontamination methods for LWRs. Emphasis is on the chemical cleaning of primary systems and contaminated equipment and components. The equipment is composed primarily of stainless steel, Inconel, Zircaloy, and a few other materials. Variables affecting efficiency are discussed. 10 figures. (DLC)
Date: May 23, 1979
Creator: Perrigo, L. D. & Divine, J. R.
System: The UNT Digital Library
Fatigue-crack propagation response of two nickel-base alloys in a liquid sodium environment (open access)

Fatigue-crack propagation response of two nickel-base alloys in a liquid sodium environment

The elevated temperature fatigue-crack propagation response of Inconel 600 and Inconel 718 was characterized within a linear-elastic fracture mechanics framework in air and low-oxygen liquid sodium environments. The crack growth rates of both nickel-base alloys tested in liquid sodium were found to be considerably lower than those obtained in air. This enhanced fatigue resistance in sodium was attributed to the very low oxygen content in the inert sodium environment. Electron fractographic examination of the Inconel 600 and Inconel 718 fatigue fracture surfaces revealed that operative crack growth mechanisms were dependent on the prevailing stress intensity level. Under low growth rate conditions, Inconel 600 and Inconel 718 fracture surfaces exhibited a faceted, crystallographic morphology in both air and sodium environments. In the higher growth rate regime, fatigue striations were observed; however, striations formed in sodium were rather ill-defined. These indistinct striations were attributed to the absence of oxygen in the liquid sodium environment. Striation spacing measurements were found to be in excellent agreement with macroscopic growth rates in both environments.
Date: January 23, 1979
Creator: Mills, W. J. & James, L. A.
System: The UNT Digital Library
Permeability of generic repository rocks at simulated in situ conditions. [Comparison of Westerly granite and White Lake genissic granite] (open access)

Permeability of generic repository rocks at simulated in situ conditions. [Comparison of Westerly granite and White Lake genissic granite]

New laboratory data are reported on the effect of confining (lithostatic) pressure, pore-water pressure, and principal stress difference on permeability of Westerly granite and White Lake gneissic granite. Permeabilities as low as 10/sup -19/ cm/sup 2/ (10/sup -11/ D) have been measured successfully, using a transient technique. Principal strains, electrical conductivity, and compressional velocity are determined simultaneously. Applied loads on the 15-cm diameter by 28-cm long test sample are controlled automatically and all data are taken by a microcomputer. Results on the gneissic granite indicate permeabilities of 10/sup -18/ to 10/sup -19/ cm/sup 2/ that appear to be unaffected either by effective pressure or by stress. The granite yields permeabilities of 4x10/sup -16/ cm/sup 2/ that decrease by a factor of two with pressure and vary by a factor of two with stress. When compared to the initial value, compressional velocities increase by 4% and conductivity decreases by 50% as pressure is increased to 50 MPa in the gneissic granite. In granite, these become 3% and 58%, respectively. At pressure, loading of the granite of 0.5 of failure stress increases conductivity by about 20%.
Date: April 23, 1979
Creator: Heard, H.C.; Trimmer, D.; Duba, A. & Bonner, B.
System: The UNT Digital Library
Nova: the laser fusion breakeven experiment (open access)

Nova: the laser fusion breakeven experiment

A new laboratory building is being constructed adjacent to the Shiva laser to house the Phase I $137M ten-beam Nova laser and a target chamber designed for twenty beams. The first ten beams will be operational in early 1980. Following Phase I, it is planned that the Shiva laser will be shut down and upgraded into ten Nova laser beams. These beams will then be combined with Nova Phase I beams to provide the full twenty beams having a minimum output energy of 300 kJ in a 3 nc pulse, or a power capability of 300 terawatts (10/sup 12/ watts) in a 100 ps pulse. This paper will describe the Phase I engineering project.
Date: October 23, 1979
Creator: Godwin, R. O.; Glaze, J. A.; Hagen, W. F.; Holzrichter, J. F.; Simmons, W. W. & Trenholme, J. B.
System: The UNT Digital Library
Monte Carlo Method for calculating fusion product behavior in field-reversed mirrors (open access)

Monte Carlo Method for calculating fusion product behavior in field-reversed mirrors

A unique model of fusion product (fp) slowing down and thermalization in field-reversed mirror (FRM) plasmas has been developed. It couples the Hill's spherical vortex representation of a field-reversed equilibrium with a monte carlo treatment of coulomb scattering, and thus provides a complete picture of fps from birth through their thermal diffusion. The incorporation of drag and scattering effects allows the code to address both the energy deposition and the ash buildup question. Results of several test cases are presented along with selected results from FRM studies.
Date: April 23, 1979
Creator: Driemeyer, D.; Miley, G. & Condit, W.
System: The UNT Digital Library
Energy coupling in the plasma focus (open access)

Energy coupling in the plasma focus

Experiments have been performed with a 125-kJ plasma focus to investigate mechanisms for rapid coupling of inductively-stored energy into plasmas. The coupling can take place through the formation of an electron or ion beam that deposits its energy in a target or directly by the penetration of the magnetic field into a resistive plasma. Some preliminary results from experiments of both types are described. The experiments use a replaceable conical anode tip that is intended to guide the focus to within a few millimeters of the axis, where it can suddenly deliver energy either to a small target or to particles that are accelerated. X-ray and fast-ion diagnostics have been used to study the effects.
Date: April 23, 1979
Creator: Wainwright, T. E.; Pickles, W. L.; Sahlin, H. L. & Price, D. F.
System: The UNT Digital Library