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Fiber-optic shock position sensor

Description: This report describes work performed for the development of a fiber-optic shock position sensor used to measure the location of a shock front in the neighborhood of a nuclear explosion. Such a measurement would provide a hydrodynamic determination of nuclear yield. The original proposal was prompted by the Defense Nuclear Agency's interest in replacing as many electrical sensors as possible with their optical counterparts for the verification of a treaty limiting the yield of a nuclear device used in underground testing. Immunity to electromagnetic pulse is the reason for the agency's interest; unlike electrical sensors and their associated cabling, fiber-optic systems do not transmit to the outside world noise pulses from the device containing secret information.
Date: March 1, 1993
Creator: Weiss, J.D.
Partner: UNT Libraries Government Documents Department

Preliminary nuclear safety assessment of the NEPST (Topaz II) space reactor program

Description: The United States (US) Strategic Defense Initiative Organization (SDIO) decided to investigate the possibility of launching a Russian Topaz II space nuclear power system. A preliminary nuclear safety assessment was conducted to determine whether or not a space mission could be conducted safely and within budget constraints. As part of this assessment, a safety policy and safety functional requirements were developed to guide both the safety assessment and future Topaz II activities. A review of the Russian flight safety program was conducted and documented. Our preliminary nuclear safety assessment included a number of deterministic analyses, such as; neutronic analysis of normal and accident configurations, an evaluation of temperature coefficients of reactivity, a reentry and disposal analysis, an analysis of postulated launch abort impact accidents, and an analysis of postulated propellant fire and explosion accidents. Based on the assessment to date, it appears that it will be possible to safely launch the Topaz II system in the US with a modification to preclude water flooded criticality. A full scale safety program is now underway.
Date: January 1, 1993
Creator: Marshall, A.C.
Partner: UNT Libraries Government Documents Department

Thermionic system evaluation test (TSET) facility construction: A United States and Russian effort

Description: The Thermionic System Evaluation Test (TSET) is a ground test of an unfueled Russian TOPAZ-II in-core thermionic space reactor powered by electric heaters. The facility that will be used for testing of the TOPAZ-II systems is located at the New Mexico Engineering Research Institute (NMERI) complex in Albuquerque, NM. The reassembly of the Russian test equipment is the responsibility of International Scientific Products (ISP), a San Jose, CA, company and Inertek, a Russian corporation, with support provided by engineers and technicians from Phillips Laboratory (PL), Sandia National Laboratories (SNL), Los Alamos National Laboratory (LANL), and the University of New Mexico (UNM). This test is the first test to be performed under the New Mexico Strategic Alliance agreement. This alliance consist of the PL, SNL, LANL, and UNM. The testing is being funded by the Strategic Defense Initiative Organization (SDIO) with the PL responsible for project execution.
Date: January 1, 1992
Creator: Wold, S.K.
Partner: UNT Libraries Government Documents Department

An efficient parallel algorithm for matrix-vector multiplication

Description: The multiplication of a vector by a matrix is the kernel computation of many algorithms in scientific computation. A fast parallel algorithm for this calculation is therefore necessary if one is to make full use of the new generation of parallel supercomputers. This paper presents a high performance, parallel matrix-vector multiplication algorithm that is particularly well suited to hypercube multiprocessors. For an n x n matrix on p processors, the communication cost of this algorithm is O(n/[radical]p + log(p)), independent of the matrix sparsity pattern. The performance of the algorithm is demonstrated by employing it as the kernel in the well-known NAS conjugate gradient benchmark, where a run time of 6.09 seconds was observed. This is the best published performance on this benchmark achieved to date using a massively parallel supercomputer.
Date: March 1, 1993
Creator: Hendrickson, B.; Leland, R. & Plimpton, S.
Partner: UNT Libraries Government Documents Department

Elastic dynamics of a complete wind turbine structure: Theoretical development

Description: This paper develops a pseodo-linear formulation of the equations of motion for analyzing elastic bodies which undergo large rotations relative to one another with an emphasis on its application to HAWTs. This procedure greatly simplifies the computational aspects of the solution algorithm over the nonlinear alternatives and should yield a significant improvement in computer speed. Additional speed can be achieved by ordering the nodes such that a minimum bandwidth can be realized (leading to approximately 64 multiplications per degree of freedom per solution step). The formulation utilizes a set of nested moving coordinate systems, each of which is loosely tied to one of the elastic bodies such that the displacements in the body relative to its coordinate system remain small. The formulation also includes a scheme for handling the nonlinear geometric stiffness that occurs in the blades as a result of the centrifugal loads in a pseudo-linear fashion.
Date: January 1, 1992
Creator: Lobitz, D.W.; Arguello, J.G. & Veers, P.S.
Partner: UNT Libraries Government Documents Department

Downhole material injector for lost circulation control

Description: This invention is comprised of an apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.
Date: January 1, 1991
Creator: Glowka, D.A.
Partner: UNT Libraries Government Documents Department

A methodology for estimating the residual contamination contribution to the source term in a spent-fuel transport cask

Description: This report describes the ranges of the residual contamination that may build up in spent-fuel transport casks. These contamination ranges are calculated based on data taken from published reports and from previously unpublished data supplied by cask transporters. The data involve dose rate measurements, interior smear surveys, and analyses of water flushed out of cask cavities during decontamination operations. A methodology has been developed to estimate the effect of residual contamination on spent-fuel cask containment requirements. Factors in estimating the maximum permissible leak rates include the form of the residual contamination; possible release modes; internal gas-borne depletion; and the temperature, pressure, and vibration characteristics of the cask during transport under normal and accident conditions. 12 refs., 9 figs., 4 tabs.
Date: September 1, 1991
Creator: Sanders, T.L. (Sandia National Labs., Albuquerque, NM (United States)); Jordan, H. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant); Pasupathi, V. (Battelle, Columbus, OH (United States)); Mings, W.J. (USDOE Idaho Field Office, Idaho Falls, ID (United States)) & Reardon, P.C. (GRAM, Inc., Albuquerque, NM (United States))
Partner: UNT Libraries Government Documents Department

Multidimensional spectral load balancing

Description: We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.
Date: January 1, 1993
Creator: Hendrickson, B. & Leland, R.
Partner: UNT Libraries Government Documents Department

An improved spectral graph partitioning algorithm for mapping parallel computations

Description: Efficient use of a distributed memory parallel computer requires that the computational load be balanced across processors in a way that minimizes interprocessor communication. We present a new domain mapping algorithm that extends recent work in which ideas from spectral graph theory have been applied to this problem. Our generalization of spectral graph bisection involves a novel use of multiple eigenvectors to allow for division of a computation into four or eight parts at each stage of a recursive decomposition. The resulting method is suitable for scientific computations like irregular finite elements or differences performed on hypercube or mesh architecture machines. Experimental results confirm that the new method provides better decompositions arrived at more economically and robustly than with previous spectral methods. We have also improved upon the known spectral lower bound for graph bisection.
Date: September 1, 1992
Creator: Hendrickson, B. & Leland, R.
Partner: UNT Libraries Government Documents Department

An estimate of the cost of electricity production from hot-dry rock

Description: This paper gives an estimate of the cost to produce electricity from hot-dry rock (HDR). Employment of the energy in HDR for the production of electricity requires drilling multiple wells from the surface to the hot rock, connecting the wells through hydraulic fracturing, and then circulating water through the fracture system to extract heat from the rock. The basic HDR system modeled in this paper consists of an injection well, two production wells, the fracture system (or HDR reservoir), and a binary power plant. Water is pumped into the reservoir through the injection well where it is heated and then recovered through the production wells. Upon recovery, the hot water is pumped through a heat exchanger transferring heat to the binary, or working, fluid in the power plant. The power plant is a net 5.1-MW[sub e] binary plant employing dry cooling. Make-up water is supplied by a local well. In this paper, the cost of producing electricity with the basic system is estimated as the sum of the costs of the individual parts. The effects on cost of variations to certain assumptions, as well as the sensitivity of costs to different aspects of the basic system, are also investigated.
Date: January 1, 1993
Creator: Pierce, K.G. (Sandia National Labs., Albuquerque, NM (United States)) & Livesay, B.J. (Livesay Consultants, Inc., Encinitas, CA (United States))
Partner: UNT Libraries Government Documents Department

The status of the US VAWT program

Description: Vertical axis wind turbine (VAWT) technology in the United States started in the early 1970s directly from the original work in Canada. The close, and very productive relationships among laboratories, universities and industry have continued since that time. This paper briefly discusses the significant technical progress and rather dramatic programmatic changes that have occurred in the past 18 to 24 months on the US side of the border. 20 refs., 14 figs.
Date: January 1, 1991
Creator: Dodd, H.M.; Berg, D.E.; Ashwill, T.D.; Sutherland, H.J. & Schluter, L.L.
Partner: UNT Libraries Government Documents Department

Comparison of analytic Whipple bumper shield ballistic limits with CTH simulations

Description: A series of CTH simulations were conducted to assess the feasibility of using the hydrodynamic code for debris cloud formation and to predict any damage due to the subsequent loading on rear structures. Six axisymmetric and one 3-dimensional simulations were conducted for spherical projectiles impacting Whipple bumper shields. The projectile diameters were chosen to correlate with two well known analytic expressions for the ballistic limit of a Whipple bumper shield. It has been demonstrated that CTH can be used to simulate the debris cloud formation, the propagation of the debris across a void region, and the secondary impact of the debris against a structure. In addition, the results from the CTH simulations were compared to the analytic estimates of the ballistic limit. At impact velocities of 10 km/s or less, the CTH predicted ballistic limit lays between the two analytic estimates. However, for impact velocities greater than 10 km/s, CTH simulations predicted a ballistic limit larger than both analytical estimates. The differences at high velocities are not well understood. Structural failure at late times due to the time integrated loading of a very diffuse debris cloud has not been considered in the CTH model. In addition, the analytic predictions are extrapolated from relatively low velocity data and the extrapolation technique may not be valid. The discrepancy between the two techniques should be investigated further.
Date: May 1, 1993
Creator: Hertel, E.S. Jr.
Partner: UNT Libraries Government Documents Department

Portable, solid state, fiber optic coupled doppler interferometer system for detonation and shock diagnostics

Description: VISAR (Velocity Interferometer System for Any Reflector) is a specialized Doppler interferometer system that is gaining world-wide acceptance as the standard for shock phenomena analysis. The VISAR's large power and cooling requirements, and the sensitive and complex nature of the interferometer cavity has restricted the traditional system to the laboratory. This paper describes the new portable VISAR, its peripheral sensors, and the role it played in optically measuring ground shock of an underground nuclear detonation (UGT). The Solid State VISAR uses a prototype diode pumped ND:YAG laser and solid state detectors that provide a suitcase-size system with low power requirements. A special window and sensor was developed for fiber optic coupling (1 kilometer long) to the VISAR. The system has proven itself as a reliable, easy-to-use instrument that is capable of field test use and rapid data reduction employing only a personal computer (PC).
Date: January 1, 1993
Creator: Fleming, K.J. & Crump, O.B.
Partner: UNT Libraries Government Documents Department

Overview: Hard Rock Penetration

Description: The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.
Date: January 1, 1992
Creator: Dunn, J.C.
Partner: UNT Libraries Government Documents Department

Shock characterization of Diallyl Phthalate (DAP)

Description: This study involved the shock characterization of Diallyl Phthalate (DAP), in particular, the equation of state as measured by the shock Hugoniot. Tests were done between 1 and 11 GPa impact shock pressure. The Hugoniot parameters were determined to be: [rho][sub 0]= 1.743, C[sub 0] = 2.20, and S = 2.33.
Date: September 1, 1992
Creator: Weirick, L.J.
Partner: UNT Libraries Government Documents Department

Sensor Based Process Control (SBPC) Laboratories Directed Research and Development (LDRD)

Description: This report describes the activities and results of an LDRD entitled Sensor Based Process Control. This research examined the needs of the plating industry for monitor and control capabilities with particular emphasis on water effluent from rinse baths. A personal computer-based monitor and control development system was used as a test bed.
Date: March 1, 1993
Creator: Wronosky, J.B.
Partner: UNT Libraries Government Documents Department

Utilization of low rank coals in liquefaction

Description: The objective of the current MITRE study is to estimate the cost of the coal derived liquid products that result from processing low rank coals in the Wilsonville and HRI CTSL configurations. The resultant cost of liquids is then compared to liquids produced from bituminous coals. The methodology used to accomplish the above objective was to utilize the MITRE coal liquefaction cost model to assess the overall technical and economic performance of low rank coals in both the Wilsonville and HRI configurations. Actual test data from Wilsonville and HRI was used as the basis for these analyses. This test data is modified to simulate complete resid recycle extinction and to standardize the operating performance of the deashing unit. This corrected yield data is then used in the simulation models to predict the overall performance and economics of a conceptual commercial coal liquefaction facility. 9 refs., 7 figs.
Date: January 1, 1991
Creator: Gray, D. (Mitre Corp., McLean, VA (United States))
Partner: UNT Libraries Government Documents Department

Intelligent System Controller for remote systems

Description: The US Department of Energy's Office of Technology Development (OTD) has sponsored the development of the Generic Intelligent System Controller (GISC) for application to the clean up of hazardous waste sites. Of primary interest to the OTD is the development of technologies which result in faster, safer, and cheaper cleanup of hazardous waste sites than possible using conventional approaches. An objective of the GISC development project is to achieve these goals by developing a modular robotics control approach which reduces the time and cost of development by allowing reuse of control system software and uses computer models to improve the safety of remote site cleanup while reducing the time and life cycle costs.
Date: January 1, 1992
Creator: Harrigan, R.W.
Partner: UNT Libraries Government Documents Department

Radionuclide inventories for short run-time space nuclear reactor systems

Description: Space Nuclear Reactor Systems, especially those used for propulsion, often have expected operation run times much shorter than those for land-based nuclear power plants. This produces substantially different radionuclide inventories to be considered in the safety analyses of space nuclear systems. This presentation describes an analysis utilizing ORIGEN2 and DKPOWER to provide comparisons among representative land-based and space systems. These comparisons enable early, conceptual considerations of safety issues and features in the preliminary design phases of operational systems, test facilities, and operations by identifying differences between the requirements for space systems and the established practice for land-based power systems. Early indications are that separation distance is much more effective as a safety measure for space nuclear systems than for power reactors because greater decay of the radionuclide activity occurs during the time to transport the inventory a given distance. In addition, the inventories of long-lived actinides are very low for space reactor systems.
Date: October 22, 1992
Creator: Coats, R.L.
Partner: UNT Libraries Government Documents Department

A source-term method for determining spent-fuel transport cask containment requirements: Executive summary

Description: This Executive Summary presents the methodology for determining containment requirements for spent-fuel transport casks under normal and hypothetical accident conditions. Three sources of radioactive material are considered: (1) the spent fuel itself, (2) radioactive material, referred to as CRUD, attached to the outside surfaces of fuel rod cladding, and (3) residual contamination adhering to interior surfaces of the cask cavity. The methodologies for determining the concentrations of freely suspended radioactive materials within a spent-fuel transport cask for these sources are discussed in much greater detail in three companion reports: A Method for Determining the Spent-Fuel Contribution to Transport Cask Containment Requirements,'' Estimate of CRUD Contribution to Shipping Cask Containment Requirements,'' and A Methodology for Estimating the Residual Contamination Contribution to the Source Term in a Spent-Fuel Transport Cask.'' Examples of cask containment requirements that combine the individually determined containment requirements for the three sources are provided, and conclusions from the three companion reports to this Executive Summary are presented.
Date: February 1, 1993
Creator: Sanders, T.L.; Seager, K.D. (Sandia National Labs., Albuquerque, NM (United States)) & Reardon, P.C. (GRAM, Inc., Albuquerque, NM (United States))
Partner: UNT Libraries Government Documents Department

Design of the support structure, drive pedestal, and controls for a solar concentrator

Description: The glass/metal McDonnell-Douglas dish is the state-of-the-art of parabolic dish concentrators. Because of the perceived high production cost of this concentrator, the Department of Energy's Solar Thermal Program is developing stretch-membrane technology for large (75 kWt) solar concentrators for integration with receivers and engines in 25 kWe dish-Stirling systems. The objective of this development effort is to reduce the cost of the concentrator while maintaining the high levels of performance characteristic of glass-metal dishes. Under contract to Sandia National Laboratories, Science Applications International Corporation, Solar Kinetics Inc. and WG Associates are developing a faceted stretched-membrane heliostat technology. This design will result in a low-risk, near-term concentrator for dish-Stirling systems. WG Associates has designed the support structure, drives and tracking controls for this dish. The structure is configured to support 12 stretched-membrane, 3.5-meter diameter facets in a shaped dish configuration. The dish design is sized to power a dish-Stirling system capable of producing 25 kW (electric). In the design of the structure, trade-off studies were conducted to determine the best'' facet arrangement, dish contour, dish focal length, tracking control and walk-off protection. As part of the design, in-depth analyses were performed to evaluate pointing accuracy, compliance with AISC steel design codes, and the economics of fabrication and installation. Detailed fabrication and installation drawings were produced, and initial production cost estimates for the dish were developed. These issues, and the final dish design, are presented in this report. 7 refs., 33 figs., 18 tabs.
Date: August 1, 1991
Creator: Goldberg, V.R.; Ford, J.L. & Anderson, A.E. (WG Associates, Dallas, TX (United States))
Partner: UNT Libraries Government Documents Department

Advanced photovoltaic concentrator system low-cost prototype module

Description: This report describes the continued development of an extruded lens and the development of a PV receiver, both of which will be used in the Solar Engineering Applications Corporation (SEA) 10X concentrator. These efforts were pare of a pre-Concentrator Initiative Program. The 10X concentrator consists of an inexpensive, extruded linear Fresnel lens which focuses on one-sun cells which are adhesive-bonded to an anodized aluminum heat sink. Module sides are planned to be molded along with the lens and are internally reflective for improved on- and off-track performance. End caps with molded-in bearings complete the module. Ten modules are mounted in a stationary frame for simple, single-axis tracking in the east-west direction. This configuration an array, is shipped completely assembled and requires only setting on a reasonably flat surface, installing 4 fasteners, and hooking up the wires. Development of the 10-inch wide extruded lens involved one new extrusion die and a series of modifications to this die. Over 76% lens transmission was measured which surpassed the program goal of 75%. One-foot long receiver sections were assembled and subjected to evaluation tests at Sandia National Laboratories. A first group had some problem with cell delamination and voids but a second group performed very well, indicating that a full size receiver would pass the full qualification test. Cost information was updated and presented in the report. The cost study indicated that the Solar Engineering Applications Corporation concentrator system can exceed the DOE electricity cost goals of less than 6cents per KW-hr. 33 figs., 11 tabs.
Date: September 1, 1991
Creator: Kaminar, N.R.; McEntee, J. & Curchod, D. (Solar Engineering Applications Corp., San Jose, CA (United States))
Partner: UNT Libraries Government Documents Department

Methods for measuring the surface tritium inside TFTR using beta decay

Description: Three potential methods for measuring the surface tritium content of the TFTR vacuum vessel are described, each based on a different technique for measuring the in situ beta emission from tritium. These methods should be able to provide both a local and a global assessment of the tritium content within the top [approx] 1[mu]m of the inner wall surface.
Date: January 1, 1994
Creator: Zweben, S.J.; Johnson, D. & Hill, K. (Princeton Univ., NJ (United States). Plasma Physics Lab.) (and others)
Partner: UNT Libraries Government Documents Department

A replaceable reflective film for solar concentrators

Description: The 3M Company manufactures a silvered acrylic film called ECP-305 that is regarded as the preferred reflective film for use on stretched-membrane heliostats. However, ECP-305 will degrade in time, due to both corrosion of the silver layer and delamination at the film's silver-to-acrylic interface, and will eventually need to be replaced. 3M uses a very aggressive adhesive on this film, and once it is laminated, replacement is very difficult. The purpose of this investigation was the development of a replaceable reflector, a reflective film that can be easily removed and replaced. A replaceable reflector was successfully configured by laminating ECP-305 to the top surface of a smooth, dimensionally stable polymer film, with a removable adhesive applied to the underside of the polymer film. Several stages of screening and testing led to the selection of a 0.010-inch thick polycarbonate (GE 8030) as the best polymer film and a medium tack tape (3M Y-9425) was selected as the best removable adhesive. To demonstrate the feasibility of the replaceable reflector concept and to provide a real-time field test, the chosen construction was successfully applied to the 50-m{sup 2} SKI heliostat at the Central Receiver Test Facility at Sandia National Laboratories in Albuquerque. 4 refs., 13 figs., 7 tabs.
Date: September 1, 1991
Partner: UNT Libraries Government Documents Department