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Investigations of Pressure Distribution on Fast Flying Bodies

Description: "The question to be treated is: how high is the pressure in the bow wave caused by a body flying at supersonic speed, and how far reaching are the destructive effects of that wave? The pressure distribution on an s.S. and an S. projectile of normal speed has been ascertained already by the methods of measurement used at the Ballistic Institute of the Technical Academy of the German Air Forces. Now similar investigations of the conditions on especially fast-flying bodies were carried out" (p. 1).
Date: September 1946
Creator: Stamm, G.
Partner: UNT Libraries Government Documents Department

An Investigation of the Effect of Target Temperature on Projectile Penetration and Cratering

Description: Results regarding testing of steel projectiles fired into copper targets at velocities from 5,000 to 11,500 feet per second, which indicated that as target temperature is increased, the crater size also increases. Twenty-two caliber steel cylinders and steel spheres were used as projectiles.
Date: July 28, 1958
Creator: Kinard, William H. & Lambert, C. H., Jr.
Partner: UNT Libraries Government Documents Department

An Investigation of the Effect of Target Temperature on Projectile Penetration and Cratering

Description: Results regarding testing of steel projectiles fired into copper targets at velocities from 5,000 to 11,500 feet per second, which indicated that as target temperature is increased, the crater size also increases. Twenty-two caliber steel cylinders and steel spheres were used as projectiles.
Date: July 28, 1958
Creator: Kinard, William H. & Lambert, C. H., Jr.
Partner: UNT Libraries Government Documents Department

Fundamental Aerodynamic Investigations for Development of Arrow-Stabilized Projectiles

Description: "The numerous patent applications on arrow-stabilized projectiles indicate that the idea of projectiles without spin is not new, but has appeared in various proposals throughout the last decades. As far as projectiles for subsonic speeds are concerned, suitable shapes have been developed for sometime, for example, numerous grenades. Most of the patent applications, though, are not practicable particularly for projectiles with supersonic speed" (p. 1).
Date: December 1947
Creator: Kurzweg, Hermann
Partner: UNT Libraries Government Documents Department

Flight Tests of Fifteen T-231 Gun-Launched Rocket Projectiles

Description: "Flight tests of fifteen T-231 70-mm HEAA rocket projectiles (flight components of the T-263 HEAA rounds) were made at the Langley Pilotless AIrcraft Research Station at Wallops Island, VA., to obtain flight trajectories at high quadrant elevation launchings and to obtain drag data. Although all rounds were of the same general type, there were differences in nozzle cant angles, number of nozzles per round, shape of head and fuse, motor case length, and type of propellant. All projectiles were launched at an elevation angle of 60 deg" (p. 1).
Date: June 26, 1956
Creator: Lanford, Wade E.
Partner: UNT Libraries Government Documents Department

The influence of projectile neutron number in the 208Pb(48Ti, n)255Rf and 208Pb(50Ti, n)257Rf reactions

Description: Four isotopes of rutherfordium,254-257Rf, were produced by the 208Pb(48Ti, xn)256-xRf and 208Pb(50Ti, xn)258-xRf reactions (x = 1, 2) at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. Excitation functions were measured for the 1n and 2n exit channels. A maximum likelihood technique, which correctly accounts for the changing cross section at all energies subtended by the targets, was used to fit the 1n data to allow a more direct comparison between excitation functions obtained under different experimental conditions. The maximum 1n crosssections of the 208Pb(48Ti, n)255Rf and 208Pb(50Ti, n)257Rf reactions obtained from fits to the experimental data are 0.38 +/- 0.07 nb and 40 +/-5 nb, respectively. Excitation functions for the 2n exit channel were also measured, with maximum cross sections of nb for the 48Ti induced reaction, and 15.7 +/- 0.2 nb for the 50Ti induced reaction. The impact of the two neutron difference in the projectile on the 1n cross section is discussed. The results are compared to the Fusion by Diffusion model developed by Swiatecki, Wilczynska, and Wilczynski.
Date: July 11, 2008
Creator: Dragojevic, Irena; Dragojevic, I.; Gregorich, K.E.; Dullmann, Ch.E.; Garcia, M.A.; Gates, J.M. et al.
Partner: UNT Libraries Government Documents Department

Penetration Experiments with 6061-T6511 Aluminum Targets and Spherical-Nose Steel Projectiles at Striking Velocities Between 0.5 and 3.0 km/s

Description: We conducted depth of penetration experiments with 7.11-mm-diameter, 74.7-mm-long, spherical-nose, 4340 steel projectiles launched into 250-mm-diameter, 6061-T6511 aluminum targets. To show the effect of projectile strength, we used projectiles that had average Rockwell harnesses of R{sub c} = 36.6, 39.5, and 46.2. A powder gun and two-stage, light-gas guns launched the 0.023 kg projectiles at striking velocities between 0.5 and 3.0 km/s. Post-test radiographs of the targets showed three response regions as striking velocities increased: (1) the projectiles remained visibly undeformed, (2) the projectiles permanently deformed without erosion, and (3) the projectiles eroded and lost mass. To show the effect of projectile strength, we compared depth-of-penetration data as a function of striking velocity for spherical-nose rods with three Rockwell harnesses at striking velocities ranging from 0.5 to 3.0 km/s. To show the effect of nose shape, we compared penetration data for the spherical-nose projectiles with previously published data for ogive-nose projectiles.
Date: February 4, 1999
Creator: Forrestal, M.J. & Piekutowski, A.J.
Partner: UNT Libraries Government Documents Department

A study of the effect of grain size on the ballistic performance of silicon carbide

Description: The depth of penetration method was used to ballistically evaluate the performance of silicon carbide as a function of grain size. The hot-pressed silicon carbide was backed by 4340 steel Rc = 35 and impacted by tungsten heavy metal projectiles of L/D = 4 at velocities of 1.6 and 1/75 km/s. The hot-pressed silicon carbide was also compared with reaction-sintered silicon carbide of identical thickness in the current study. Results are compared with data previously reported by others.
Date: March 1, 1995
Creator: Cline, C.F.
Partner: UNT Libraries Government Documents Department


Description: Interactions between Ar projectiles and lead are studied in terms of global observables. The Streamer Chamber at the Berkeley BEVALAC was used to record all charged particles produced in collisions between 0.8 GeV/{mu} Ar projectiles with a Pb{sub 3}O{sub 4} target. A hardware trigger selected central collisions with PB nuclei corresponding to a trigger cross section of 1 barn. In a geometrical picture this is equivalent to an impact parameter range of 0--5 fm.
Date: August 1, 1983
Creator: Renfordt, R.E.
Partner: UNT Libraries Government Documents Department


Description: Two independent emulsion experiments using Bevalac beams of {sup 16}O and {sup 56}Fe at {approx}2 GeV/nucleon find with > 99.7% confidence that the reaction mean-free paths of projectile fragments, 3 {approx}< Z {approx}< 26, are shorter for a few centimeters after their emission than at larger distances, or than predicted from experiments on beam nuclei. This effect, which is enhanced in later generations of fragments, can be interpreted by the relatively rare occurrence of fragments that interact with an unexpectedly large cross section.
Date: June 1, 1980
Creator: Friedlander, E.M.; Gimpel, R.W.; Heckman, H.H.; Karant, Y.J.; Judek, B. & Ganssauge, E.
Partner: UNT Libraries Government Documents Department

Optical bullet-tracking algorithms for weapon localization in urban environments

Description: Localization of the sources of small-arms fire, mortars, and rocket propelled grenades is an important problem in urban combat. Weapons of this type produce characteristic signatures, such as muzzle flashes, that are visible in the infrared. Indeed, several systems have been developed that exploit the infrared signature of muzzle flash to locate the positions of shooters. However, systems based on muzzle flash alone can have difficulty localizing weapons if the muzzle flash is obscured or suppressed. Moreover, optical clutter can be problematic to systems that rely on muzzle flash alone. Lawrence Livermore National Laboratory (LLNL) has developed a projectile tracking system that detects and localizes sources of small-arms fire, mortars and similar weapons using the thermal signature of the projectile rather than a muzzle flash. The thermal signature of a projectile, caused by friction as the projectile travels along its trajectory, cannot be concealed and is easily discriminated from optical clutter. The LLNL system was recently demonstrated at the MOUT facility of the Aberdeen Test Center [1]. In the live-fire demonstration, shooters armed with a variety of small-arms, including M-16s, AK-47s, handguns, mortars and rockets, were arranged at several positions in around the facility. Experiments ranged from a single-weapon firing a single-shot to simultaneous fire of all weapons on full automatic. The LLNL projectile tracking system was demonstrated to localize multiple shooters at ranges up to 400m, far greater than previous demonstrations. Furthermore, the system was shown to be immune to optical clutter that is typical in urban combat. This paper describes the image processing and localization algorithms designed to exploit the thermal signature of projectiles for shooter localization. The paper begins with a description of the image processing that extracts projectile information from a sequence of infrared images. Key to the processing is an adaptive spatio-temporal filter developed to ...
Date: March 31, 2006
Creator: Roberts, R S & Breitfeller, E F
Partner: UNT Libraries Government Documents Department

Simulations of Fracture and Fragmentation of Geologic Materials using Combined FEM/DEM/SPH Analysis

Description: An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model this class of problems, LDEC now includes implementations of Cosserat point theory and cohesive elements. This approach directly simulates the transition from continuum to discontinuum behavior, thereby allowing for dynamic fracture within a combined finite element/discrete element framework. In addition, a Smooth Particle Hydrodynamics (SPH) capability has been incorporated into LDEC, permitting the simulation of fluid-structure interaction. We will present results from a study of detonation-induced fracture and fragmentation of geologic media surrounding a tunnel using LDEC.
Date: April 5, 2007
Creator: Morris, J P & Johnson, S M
Partner: UNT Libraries Government Documents Department

B(E1) Strengths from Coulomb excitation of 11Be

Description: The B(E1;1/2{sup +}{yields} 1/2{sup -}) strength for {sup 11}Be has been extracted from intermediate energy Coulomb excitation measurements, over a range of beam energies using a new reaction model, the extended continuum discretized coupled channels (XCDCC) method. In addition, a measurement of the excitation cross section for {sup 11}Be+{sup 208}Pb at 38.6 MeV/nucleon is reported. The B(E1) strength of 0.105(12) e{sup 2}fm{sup 2} derived from this measurement is consistent with those made previously at 60 and 64 MeV/nucleon, in contrast to an anomalously low result obtained at 43 MeV/nucleon. By coupling a multi-configuration description of the projectile structure with realistic reaction theory, the XCDCC model provides for the first time a fully quantum mechanical description of Coulomb excitation. The XCDCC calculations reveal that the excitation process involves significant contributions from nuclear, continuum, and higher-order effects. An analysis of the present and two earlier intermediate energy measurements yields a combined B(E1) strength of 0.105(7) e{sup 2}fm{sup 2}. This value is in good agreement with the value deduced independently from the lifetime of the 1/2{sup -} state in {sup 11}Be, and has a comparable precision.
Date: March 6, 2007
Creator: Summers, N. C.; Pain, S. D.; Orr, N. A.; Catford, W. N.; Angelique, J. C.; Ashwood, N I et al.
Partner: UNT Libraries Government Documents Department

Multispectral thermal imager observations of the moon during total eclipse.

Description: Lunar eclipse temperature measurements are sensitive to rock populations because surfaces with abundant exposed rock have much higher mean thermal inertias than surfaces dominated by fine powders . When the Moon passes into the I :arth's shadow, the abrupt reduction in insolation causes surfacc elements to cool at rates which are ILnctions oftheir thermal inertia . The rock population is a lunction of the exposure of a surface unit, originally composed of solid igneous rock or impact mclt, to the impact flux of modest sized projectiles. With time, a competent surface such as a lava flow field or an impact melt sheet will be comminuted by the impact flux reducing the ratio of coarse to fine particles . In principle, thermal measurements taken during lunar eclipse can be used as a measure of the relative age of surface units .
Date: January 1, 2003
Creator: Lawson, S. L. (Stefanie L.); Rodger, A. P. (Andrew Paul); Bender, S. C. (Steven C.); Lucey, P. G. (Paul G.) & Henderson, B. G. (Bradley G.)
Partner: UNT Libraries Government Documents Department

Simulation of penetration into porous geologic media

Description: We present a computational study on the penetration of steel projectiles into porous geologic materials. The purpose of the study is to extend the range of applicability of a recently developed constitutive model to simulations involving projectile penetration into geologic media. The constitutive model is non-linear, thermodynamically consistent, and properly invariant under superposed rigid body motions. The equations are valid for large deformations and they are hyperelastic in the sense that the stress tensor is related to a derivative of the Helmholtz free energy. The model uses the mathematical structure of plasticity theory to capture the basic features of the mechanical response of geological materials including the effects of bulking, yielding, damage, porous compaction and loading rate on the material response. The new constitutive model has been successfully used to simulate static laboratory tests under a wide range of triaxial loading conditions, and dynamic spherical wave propagation tests in both dry and saturated geologic media.
Date: May 31, 2005
Creator: Vorobiev, O Y; Liu, B T; Lomov, I N & Antoun, T
Partner: UNT Libraries Government Documents Department

Data Association and Bullet Tracking Algorithms for the Fight Sight Experiment

Description: Previous LLNL investigators developed a bullet and projectile tracking system over a decade ago. Renewed interest in the technology has spawned research that culminated in a live-fire experiment, called Fight Sight, in September 2005. The experiment was more complex than previous LLNL bullet tracking experiments in that it included multiple shooters with simultaneous fire, new sensor-shooter geometries, large amounts of optical clutter, and greatly increased sensor-shooter distances. This presentation describes the data association and tracking algorithms for the Fight Sight experiment. Image processing applied to the imagery yields a sequence of bullet features which are input to a data association routine. The data association routine matches features with existing tracks, or initializes new tracks as needed. A Kalman filter is used to smooth and extrapolate existing tracks. The Kalman filter is also used to back-track bullets to their point of origin, thereby revealing the location of the shooter. It also provides an error ellipse for each shooter, quantifying the uncertainty of shooter location. In addition to describing the data association and tracking algorithms, several examples from the Fight Sight experiment are also presented.
Date: October 7, 2005
Creator: Breitfeller, E & Roberts, R
Partner: UNT Libraries Government Documents Department


Description: The results of cross-section measurements for the reactions {sup 209}Bi({sup 12}C,X)Au, E = 4.8 and 25.2 GeV and {sup 209}Bi({sup 20}Ne,X)Au, E = 8.0 GeV are reported. The observed yields of the gold isotopes show a similar dependence on mass number for each reaction, differing slightly in the position of the centroid of the distribution. As the projectile energy increases, the inferred excitation energy of the primary residues remains the same or decreases slightly. This observation is in agreement with the predictions of the intranuclear cascade model of relativistic heavy ion collisions.
Date: July 1, 1980
Creator: Aleklett, K.; Morrissey, D.J.; Loveland, W.; McGaughey, P.L. & Seaborg, g.T.
Partner: UNT Libraries Government Documents Department

19 mm ballistic range: a potpourri of techniques and recipes

Description: The expansion of ballistic gun range facilities at LLL has introduced state-of-the-art diagnostic techniques to glovebox-enclosed ballistic guns systems. These enclosed ballistic ranges are designed for the study of one- dimensional shock phenomena in extremely toxic material such as plutonium. The extension of state-of-the-art phtographic and interferometric diagnostic systems to glovebox-enclosed gun systems introduces new design boundaries and performance criteria on optical and mechanical components. A technique for experimentally evaluating design proposals is illustrated, and several specific examples (such as, target alignment, collateral shrapnel damage, and soft recovery) are discussed. (auth)
Date: September 23, 1975
Creator: Carpluk, G.T.
Partner: UNT Libraries Government Documents Department

Modeling heavy ion ionization energy loss at low and intermediate energies

Description: The needs of contemporary accelerator and space projects led to significant efforts made to include description of heavy ion interactions with matter in general-purpose Monte Carlo codes. This paper deals with an updated model of heavy ion ionization energy loss developed previously for the MARS code. The model agrees well with experimental data for various projectiles and targets including super-heavy ions in low-Z media.
Date: November 1, 2009
Creator: Rakhno, I.L.
Partner: UNT Libraries Government Documents Department

Test Design Calculations II

Description: In an earlier report, we presented results of modeling calculations for one simple geometry that represents an experiment potentially to be performed at Sandia National Laboratory, which is examining equation of state issues of interest to the National Missile Defense Program. In the earlier report, we showed snapshots of calculations with two different initial zone dimensions for Gruneisen EOS and LEOS. We also showed pressure profiles at various locations in a witness plate out of the way of direct projectile impact, but hit by shrapnel generated during impact. It was found that the pressure profiles exhibit strong dependence on location, zone size, and equation of state. In this report we examine the overall momentum impacted to the witness plate. This momentum shows negligible dependence on the equation of state and some dependence on zone size.
Date: July 27, 2000
Creator: Gerassimenko, M.
Partner: UNT Libraries Government Documents Department

Test Problems for Reactive Flow HE Model in the ALE3D Code and Limited Sensitivity Study

Description: We document quick running test problems for a reactive flow model of HE initiation incorporated into ALE3D. A quarter percent change in projectile velocity changes the outcome from detonation to HE burn that dies down. We study the sensitivity of calculated HE behavior to several parameters of practical interest where modeling HE initiation with ALE3D.
Date: March 1, 2000
Creator: Gerassimenko, M.
Partner: UNT Libraries Government Documents Department

On how to make the fastest gun in the west

Description: A new gasdynamic launcher is described, in which intact projectiles weighing at least one gram can be accelerated to mass velocities of 20 km/s. The system employs a conventional 2-stage light gas gun, with the barrel modified and filled with helium to act as a pump tube for a third stage. It is demonstrated that inter-stage kinetic energy efficiencies of 45% are possible and that these results can be achieved while maintaining the peak pressure applied to the projectile below 2.5 GPa. A simple analysis of this system is given, from which design parameters can be readily derived, and hydrocode calculations are presented to validate the model.
Date: January 1, 1997
Creator: Glenn, L.A.
Partner: UNT Libraries Government Documents Department

Demonstration of enhanced warhead performance with more powerful explosives

Description: Enhanced warhead performance has been demonstrated for several warhead configurations loaded with more powerful explosives. This paper presents experimental results from several warheads loaded with one of the new more powerful explosives, LX-19. The LX-19 formulation is a volume analog to LX-14 (HMX/Estane) that consists of 95.8 wt.% epsilon CL-20 formulated with 4.2 wt.% Estane binder. The LX-19 formulation, characterization, and evaluation efforts presseted in this paper are the result of several studies that have been ongoing since 1991. The warhead configurations that have been tested include a trumpet lined shaped charge, a hemispherical lined shaped cahrge, an EFP charge, and a fragmentation warhead, Performation improvements have been demonstrated with all configurations that were tested.
Date: December 1, 1997
Creator: Murphy, M.J.; Baum, D.; Simpson, R.L.; Monoto, J.; Montesi, L.; Newman, K. et al.
Partner: UNT Libraries Government Documents Department