PRONTO 3D is a three-dimensional transient solid dynamics code for analyzing large deformations of highly nonlinear materials subjected to high strain rates. It is a Lagrangian finite element program with explicit integration of the equations of motion through time. This report documents the implementation of a four-scale quadrilateral shell element into Version 6.0 of PRONTO 3D. This report describes the theory, implementation and use of a four-node shell element. Also described are the required architectural changes made to PRONTO 3D to allow multiple element types. Several test problems are documented for verification of the PRONTO 3D implementation and for demonstration of computational savings using shell elements for thin structures. These problems also serve as examples for the user. A complete, updated list of the PRONTO 3D input commands is also included.
This purpose of this NUREG is to present technical information that should be useful to NRC licensees for understanding and applying line supervision techniques to security communication links. A review of security communication links is followed by detailed discussions of link physical protection and DC/AC static supervision and dynamic supervision techniques. Material is also presented on security for atmospheric transmission and video line supervision. A glossary of security communication line supervision terms is appended. 16 figs.
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 These contamination ranges are calculated based on data taken from published reports and from previously unpublished data supplied by cask transporters.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.
Chromate conversion coatings such as Parker Company`s Alodine coatings are widely used to increase the corrosion resistance of aluminum and aluminum alloys. The primary disadvantage of chromate-based processes is that they use and produce as waste hexavalent chromium (Cr{sup 6+}). We have discovered that the corrosion resistance of Al can be increased by forming an inorganic barrier coating using chemicals that pose a relatively small environmental hazard. These new coatings are formed using a process that is procedurally identical to the basic chromate conversion process. We have prepared new and conventional coatings on 1100 (99.0 Al minimum), 2024-T3 (Al-Cu-Mg) and 7075-T6 (Al-Zn-Mg) commercial sheet stock for accelerated electrochemical testing and coating conductivity testing. Results show that the new coatings offer increased corrosion resistance compared to uncoated Al, but do not yet match the performance of the chromate conversion coatings. The conductivity of these new films on 1100 Al is comparable to that of Alodine coatings; however, the new coatings are more resistive than Alodine coatings on 2024-T3 and 7075-T6.
A novel technique to monitor thin film deposition has been developed using optical fibers. The system measures the optical thickness of a film and not the physical thickness which results in accurate film deposition for optical applications regardless of deposition conditions. A discussion of the mathematics necessary to understand the operation of the system is presented. The details of the circuitry and software are presented. The performance of the system is then demonstrated for the deposition of SnO{sub 2} on an optical fiber. An analysis of the inherent errors present in the monitor electronics and measurement system and their effects on the accuracy of the deposition is presented. The system is then applied to several practical situations. First, the system is used to monitor the deposition of SnO{sub 2} films on microscope slides. The films on the slides are then shown to have optical thicknesses which are within 1% of the expected values. The system is next used to deposit SiO anti-reflective coatings on Si. The system is then used to monitor the aging effects seen in SiO and SnO{sub 2}. Finally, a seven layer dielectric mirror made from SnO{sub 2} and MgF{sub 2} films is deposited using the monitor. 25 figs., 1 tabs.
This paper presents a series of experiments in robotic sensori-motor control during grasping. The work utilizes a multifingered, dextrous robot hand equipped with a fingertip force sensor to explore dynamic grasp force adjustment during manipulation. The work is primarily concerned with the relationship between the weight of an object and the grasp force required to lift it. Too weak a grasp is unstable and the object will slip from the hand. Too strong a grasp may damage the object and/or the manipulator. An algorithm is presented which uses tactile information from the sensor to dynamically adjust the grasp force during lift. It is assumed that there is no a priori knowledge about the object to be manipulated. The effects of different arm/hand postures and object surfaces is explored. Finally, the use of sensory data to detect unexpected object motion and to signal transitions between manipulation phases -- with the coincident triggering of new motor programs -- is investigated. 15 refs., 12 figs.
The fabrication of electronic systems has relied upon eutectic tin-lead solder for the attachment of components to printed wiring boards. Higher service temperatures are approaching the durability limits of the eutectic solder. The tin-rich, lead-free solders are being actively studied as alternate alloys. Experiments that examined the wettability of 95Sn-5Sb (wt. %), 95.5Sn-4.0Cu0.5Ag, 96.5Sn-3.5Ag, and the control solder, 60Sn-40Pb, on oxygen-free, high conductivity copper were performed. A rosin based, mildly activated (RMA) flux and three water soluble, organic acid fluxes were used in the wetting balance/meniscometer measurements. The 95.5Sn-4.0Cu-0.5Ag and 95Sn-5Sb alloys exhibited good wetting, with contact angles of 35° < θc < 55° as compared to the excellent performance of the 60Sn-40Pb material (20°< θc <35°). The fair wettability observed with the 96.5Sn 3.5Ag solder (60° < θc <75°) was due in large part to the inability of the fluxes to significantly lower the solder-flux interfacial tension. The wetting rates of the 95.5Sn-4.0Cu-0.5Ag and 95Sn 5Sb solders were comparable to those of the control; the 96.5Sn 3.5Ag alloy wetting rate was slower than the other candidates. The solder film formed on the substrate surface by the 95.5Sn-4.0Cu0.5Ag alloy was very grainy. The water soluble fluxes exhibited a larger degree of residue formation than did the RMA flux.
22nd Fluid Dynamics, Plasma Dynamics and Lasers Conference
Barnette, Daniel
A parabolized Navier-Stokes analysis of a turbulent, compressible, wake/boundary-layer flow field for a cable in tow is discussed. It is assumed that the cable is being towed by a missile-like configuration whose total drag coefficient is known. The cable is assumed to be perfectly aligned with the missile axis and is subjected to its wake. Modeled in the analysis is the far wake behind the missile, coupled with the turbulent boundary layer growth along the cable. An analytical starting solution for a parabolized Navier-Stokes code is presented. The starting solution is applicable downstream of the towing body's near wake and, therefore, circumvents the complex task of computing the towing body's flow field. An algebraic wake/boundary-layer turbulence model is used to simulate turbulent flow in both the decaying wake and growing boundary layer along the cable. Results are presented for a towing-body freestream Mach number of 5 and a Reynolds number of 36.0 x 106 per ft at select distances along a thin cable.
11th Aerodynamic Decelerator Systems Technology Conference
Fullerton, T.L.
Parachute system performance issues such as turnover and wake recontact may be influenced by velocities induced by the wake of the delivering aircraft. The magnitude and direction of these aircraft-induced velocities is dependent on the specific delivering aircraft (as characterized by its size, shape, and weight), the aircraft’s speed and flight path (including any maneuvers which it is performing), and the location on the aircraft from which the system is released. In addition, the parachute deployment sequence is of major importance. The most significant effects will tend to occur after parachute deployment since induced velocities from the aircraft may become significant when compared to the velocity of the parachute system. For example, any downwash behind an aircraft will tend to cause a parachute system, which is horizontally deployed, to fly at a more positive angle of attack. As the forward speed of the parachute system decreases after deployment, this induced angle of attack will tend to increase. This effect tends to retard the rate at which the parachute system “turns over” from a horizontal trajectory into a vertical one. On the other hand, a maneuvering aircraft might produce upwash in its wake which would produce an opposite effect. In this case, the turnover rate would be enhanced. Aircraft-induced velocities may also affect the process known as “wake recontact” in which the momentum of the parachute wake causes the wake itself to overtake the parachute. This sometimes causes severe collapse of the canopy such as reported by Spahr and Wolf. Wake recontact may be either hastened or delayed, depending upon the aircraft flight path and the parachute deployment sequence
This paper reviews some of the technical considerations and current practices for testing parachutes in conventional wind tunnels. Special challenges to the experimentalist caused by the fabric construction, flexible geometry, and bluff shape of parachutes are discussed. In particular, the topics of measurement technique, similarity considerations, and wall interference are addressed in a summary manner. Many references are cited which provide detailed coverage of the state of the art in testing methods.
Computer networks, supporting an organization's activities, are prevalent and very important to the organization's mission. Implementing a heterogenous organizational network allows the staff to select the computing environment that best supports their job requirements. This paper outlines the lessons learned implementing a heterogenous computer network based on networking standards such as TCP/IP and Ethernet. Such a network is a viable alternative to a proprietary, vendor supported network and can provide all the functionality customers expect in a computer network. 2 figs.
Two experiments, DCH-3 and DCH-4, were performed at the Surtsey test facility to investigate phenomena associated with a high-pressure melt ejection (HPME) reactor accident sequence resulting in direct containment heating (DCH). These experiments were performed using the same experimental apparatus with identical initial conditions, except that the Surtsey test vessel contained air in DCH-3 and argon in DCH-4. Inerting the vessel with argon eliminated chemical reactions between metallic debris and oxygen. Thus, a comparison of the pressure response in DCH-3 and DCH-4 gave an indication of the DCH contribution due to metal/oxygen reactions. 44 refs., 110 figs., 43 tabs.
This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned.
The title of this paper might unfairly provoke readers if it conjures up visions of vast stores of high-tech gadgets in several hundred technology warehouses'' (also known as federal laboratories) around the country, open for browsing by those in search of a bargain. That vision, unfortunately, is a mirage. The term technology transfer'' is not really as accurate as is the term technology team-work,'' a process of sharing ideas and knowledge rather than widgets. In addition, instead of discussing the efforts of more than 700 federal labs in the US, I mean to address only those nine government-owned, contractor-operated multiprogram labs run by the Department of Energy. Nevertheless, the topic of technology team-work opportunities with DOE multiprogram national lab is of significance to those concerned with increasing economic competitiveness and finding technological solutions to a host of national problems. A significant fraction of US R D capabilities rests in the nine DOE multiprogram national laboratories -- and these labs have only just begun to join the other federal laboratories in these efforts due to the passage and recent implementation of the National Competitiveness Technology Transfer Act of 1989.
The case and junction temperatures of selected integrated circuits (ICs) on the processor module of the SANDAC V computer were calculated using BETAsoft-R,'' a personal computer, thermal analysis software program. The predicted data was then compared to corresponding IC case temperature measurements from laboratory tests of a functional SANDAC V computer. Although the difference between the actual and calculated values was somewhat higher than expected, the results of the analysis indicate that BETAsoft-R'' identified the critical ICs on the processor module and that it is capable of analyzing printed circuit boards for potential thermal problems before the design layout is finalized. 8 figs., 12 tabs.
Sandia National Laboratories, Albuquerque, may soon have more responsibility for the operation of its own telephone system. The processes that constitute providing telephone service can all be improved through the use of a central data information system. We studied these processes, determined the requirements for a database system, then designed the first stages of a system that meets our needs for work order handling, trouble reporting, and ISDN hardware assignments. The design was based on an extensive set of applications that have been used for five years to manage the Sandia secure data network. The system utilizes an Ingres database management system and is programmed using the Application-By-Forms tools.
Radio-frequency (rf) electrical sources are commonly used to generate plasmas for processing of industrial materials and for related experimental work. Published descriptions of such plasmas usually include generator-power measurements, and occasionally include plasma dc-bias measurements. One or both of these quantitites are also used in industrial feedback ccontrol systems for setpoint regulation. Recent work at Sandia an elsewhere with an experimental rf discharge device (the GEC RF Reference Cell'') has shown that power and dc-bias levels are often insufficient information for specifying the state of the plasma. The plasma can have nonlinear electrical characteristics that cause harmonic generation, and the harmonic levels can depend sensitively on the impedance of the external circuitry at harmonic frequencies. Even though the harmonics may be low in amplitude, they can be directly related to large changes in plasma power and to changes in optical emission from the plasma. Consequently, in order for a worker to truly master the plasma-generation process, it is necessary to understand, measure, and control electrical characteristics of the plamsa. In this paper we describe technique that have been developed from work with the Reference Cell for making electrical measurements on rf plasmas, and we describe surprising observations of harmonic behavior. 10 refs., 4 figs.
The catalytic hydropyrolysis tests performed on coals of varying rank clearly show that high conversions and tar yields can be achieved in a fixed-bed laboratory reactor system. Each of the three types of catalysts utilized, MoS{sub 2} derived from dioxydithiomolybdate, the metal HTO catalysts, and the Pd colloidal catalysts, were shown to be effective for the bituminous coals tested. For the lower rank coals, no significant increase in conversions or tar yields preliminary tests utilizing oil agglomeration as a pretreatment provided encouraging results, with conversions and tar yields achieved similar to using the metal HTO and colloid catalysts. This pretreatment process might be effective for use in catalyst dispersal and coal cleaning, and facilitating coal introduction into a high-pressure reactor. In summary, the data obtained show that catalytic hydropyrolysis on a laboratory scale can achieve the necessary conversions and tar yields to be considered as a potentially viable process for converting coal into liquid products. Through proper dispersal of selected catalysts onto bituminous coals, conversions greater than 80% and tar yields greater than 70% can be achieved at low active metal concentrations. 12 refs., 9 figs., 7 tabs.
The objective of this review is to evaluate the South Texas Project (STP) Probabilistic Safety Analysis (PSA) for the USNRC. The PSA was reviewed for thoroughness of analysis, accuracy in plant modeling, legitimacy of assumptions, and overall quality of the work. The review is limited to the internal event analysis and the fire sequence analysis. This review is not a quantitative evaluation of the adequacy of the PSA. The adequacy of the PSA depends on the intended uses and must be addressed on a case-by-case basis by the licensee and the NRC. This review identifies strengths, weakness, and areas where additional clarification would assist the NRC in evaluating the PSA for specific regulatory purposes. The licensee, Houston Lighting and Power (HL P), reviewed a draft version of this report prior to its final release to the USNRC. The responses provided by HL P are provided in detail in appendices to this report, and they are summarized in the main body of the report. All issues raised during the review were adequately addressed by HL P in the responses. 27 refs., 4 tabs.
Pressure-pulse tests have been performed in bedded evaporites of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) site to evaluate the hydraulic properties controlling brine flow through the Salado. Hydraulic conductivities ranging from about 10{sup {minus}14} to 10{sup {minus}11} m/s (permeabilities of about 10{sup {minus}21} to 10{sup {minus}18} m{sup 2}) have been interpreted from nine tests conducted on five stratigraphic intervals within eleven meters of the WIPP underground excavations. Tests of a pure halite layer showed no measurable permeability. Pore pressures in the stratigraphic intervals range from about 0.5 to 9.3 MPa. An anhydrite interbed (Marker Bed 139) appears to be one or more orders of magnitude more permeable than the surrounding halite. Hydraulic conductivities appear to increase, and pore pressures decrease, with increasing proximity to the excavations. These effects are particularly evident within two to three meters of the excavations. Two tests indicated the presence of apparent zero-flow boundaries about two to three meters from the boreholes. The other tests revealed no apparent boundaries within the radii of influence of the tests, which were calculated to range from about four to thirty-five meters from the test holes. The data are insufficient to determine if brine flow through evaporites results from Darcy-like flow driven by pressure gradients within naturally interconnected porosity or from shear deformation around excavations connecting previously isolated pores, thereby providing pathways for fluids at or near lithostatic pressure to be driven towards the low-pressure excavations. Future testing will be performed at greater distances from the excavations to evaluate hydraulic properties and processes beyond the range of excavation effects.
Proceedings of SPIE - The International Society for Optical Engineering
Vawter, G.A.; Hietala, Vincent M.; Kravitz, Stanley H.; Meyer, W.J.
An all optical circuit in GaAs/AlGaAs for control of phased-array systems using a single photonic integrated circuit chip has the potential for high performance control of phasedarray systems from a small, lightweight, package. Such a circuit based exclusively on combinations of reverse-biased optical phase modulators, waveguide interconnects, corner reflectors, and power splitter combiners with optical-fiber output to the antenna elements has been designed at Sandia National Laboratories. This paper presents some basic features of optical phase modulators for photonic circuit applications and provide relevant performance data as achieved to date. Current structures have been shown to operate with a 76.5°/V-mm figure of merit at 1.06μm and losses as low as 2 cm-1. A novel digital phase shifter to allow direct digital control of phased arrays is also proposed and demonstrated.
A novel optical based RF beam steering system is proposed for phased-array antenna systems. The system, COMPASS (Coherent Optical Monolithic Phased Array Steering System), is based on optical heterodyning employed to produce microwave phase shifting. At the heart of the system is a monolithic Photonic Integrated Circuit (PIC) constructed entirely of passive components. Microwave power and control signal distribution to the antenna is accomplished by optical fiber, thus separating the PIC and its control functions from the antenna. This approach promises to reduce size, weight, and complexity of future phased-array antenna systems.
This report documents the as-built operational performance of Sandia's Severe Electrostatic Discharge Tester Version-3 (SSET-3) SN:2 and lists the hardware and additional documentation delivered to Division 2174 on July 31, 1991. (The supplied items are listed.) The primary emphasis of this report is to provide a qualitative and quantitative evaluation of the SSET against requirements derived from the Severe Human Body ESD model (SHBESD) (1), which is defined in terms of an equivalent circuit (Figure 1.1) and a short-circuit current waveform (Figure 1.2). This report also presents supporting information on the calibration and verification of ancillary equipment used to assess the operation of the SSET. While the documentation of the verification and calibration of ancillary equipment is somewhat lengthy, it is considered necessary because the SSET may be used in situations where its output characteristics will be critically scrutinized. Thus, the supporting documentation is necessary to lend credibility to the performance/verification measurements made on the SSET. 5 refs., 36 figs.
This document serves as the proceedings for the manual project review meeting held by Sandia's Photovoltaic Technology Research Division. It contains information supplied by each organization making a presentation at the meeting, which was held July 30 through 31, 1991 at the Sheraton Hotel in Albuquerque, New Mexico. Sessions were held to discuss national photovoltaic programs, one-sun crystalline silicon cell research, concentrator silicon cell research, and concentrating collector development.
One decade ago, Sandia National Laboratories designed and developed a nonpyrotechnic smoke generator capable of producing large quantities of low corrosivity, low toxicity chemical smoke to be used as a visual obscurant in access delay applications. Utilizing the same chemistry, a proof-of-concept advanced smoke generator is presently being tested. The testing is being conducted to evaluate two new concepts providing unique capabilities. Hemispherical stainless steel bladders are installed in spherically shaped chemical storage reservoirs. This provides positive displacement of the chemicals and permits orientation insensitive operation. Also, a specially designed nozzle/valve is being evaluated as a means of providing a multiple initiation capability. Cyclic operation could be accomplished via time delay circuitry, sensor input, or on demand from the control console. These new capabilities provide distinct advantages. Some advantages may be longer obscuration times, optimal volume obscuration, easier facility sizing, no organic seals in contact with the stored chemicals, and elimination of the requirement to use ultrahigh purity nitrogen as a propellant.