| Effect of Particle Hardness on the Penetration Behavior of Fabrics Intercalated with Dry Particles and Concentrated Particle-Fluid Suspensions |
03-Nov-2009 |
12 pages |
| Authors:
Dennis P Kalman; Richard L Merrill; Norman J Wagner; Eric D Wetzel; DELAWARE UNIV NEWARK
|
 | The penetration behavior of Kevlar fabric intercalated with dry particles and shear thickening fluids (STF), highly concentrated fluid-particle suspensions, is presented. In particular, the role of particle hardness is explored by comparing fabric treatments containing SiO2 particles, which are significantly harder than Kevlar, to treatments containing softer poly(methyl methacrylate) (PMMA) particles. The fabric testing includes yarn pull-out, quasi-static spike puncture, and ballistic penetration resistance, performed on single fabric layers. It ... |
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| A Low-Velocity 0.22-Caliber Gun System |
Aug-2009 |
18 pages |
| Authors:
Donald Little; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| An efficient method was needed to perform ballistic testing using the 0.22-cal. fragment-simulating projectiles (FSP) at low subsonic velocities in order to evaluate very thin lightweight composite and metallic materials at around 1 lb/ft2 areal density. This technical note outlines the custom gun system developed to enable this ballistic testing. |
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| Flexural Fatigue Response of Repaired S2-Glass/Vinyl Ester Composites |
Aug 2009 |
26 pages |
| Authors:
James M Sands; Uday K Vaidya; Biju Mathew; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Vacuum-assisted resin transfer molding is a promising, affordable technique for producing composite integral armor (CIA) and thick-section composites for U.S. Army-relevant applications. Among several constituents, the CIA uses S2-glass/epoxy and/or S2-glass/vinyl ester composites in its construction. The S2-glass-reinforced composite provides ballistic protection and load bearing due to the flexural loading caused from vehicle movement over various terrains. The S2-glass-reinforced composite is subjected to different levels of delamination when impacted by ... |
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| Fuzzy Logic Approach for Impact Source Identification in Ceramic Plates (Slides) |
13-Jul-2009 |
20 pages |
| Authors:
Thomas Meitzler; Ivan Wong; Harpreet Singh; Thomas Reynolds; Shashank Kamthan; Arati M Dixit; Vijay Shrama; WAYNE STATE UNIV DETROIT MI DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
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| This briefing looks at the use of fuzzy logic in non-destructive identification techniques. The method is based on the fact different impacting materials will generate different impact acoustic waves. |
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| GLEEM Testing Fixture |
Jul-2009 |
20 pages |
| Authors:
David Gray; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| A test method was used to develop a process to emplace a refractory metal liner inside a gun tube as a part of an effort at the U.S. Army Research Laboratory to develop an autofrettage gun barrel application. The process consisted of filling the liner with an elastomeric material and then slipping this arrangement into the gun tube. The ends of the liner were plugged with plastic disks, and pressure ... |
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| Progress Toward a Multidimensional Representation of Mortar Interior Ballistics |
Jun-2009 |
38 pages |
| Authors:
John R Schmidt; Michael J Nusca; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Lumped-parameter interior ballistics (IB) codes have had limited success in simulating the IB of mortars due to the complex nature of the firing event. Only near the end of the firing event does the mortar conform to the conventional ballistics model for which lumped-parameter codes were designed. Modified lumped-parameter models are capable of simulating some key mortar variables. There are significant pressure waves developed in mortars, which are due in ... |
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| Mortar Interior Ballistics: Sensitivity Studies Using IBHVG2 and Progress Toward a Multidimensional Representation |
Jun-2009 |
38 pages |
| Authors:
John R Schmidt; Michael J Nusca; Albert W Horst; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Traditionally, the interior ballistic (IB) modeling of mortars has been difficult to achieve because a mortar projectile contains certain energetic components internal to the tail boom. After ignition, high pressure generated by the igniter causes the canister to burst and release hot gases and burning particles into the larger chamber called the launch tube. Subsequently, any external charges ignite and produce gases which accelerate the projectile. A recent advancement to ... |
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| Simulation of Ballistic Impact of a Tungsten Carbide Sphere on a Confined Silicon Carbide Target |
Jun-2009 |
16 pages |
| Authors:
C G Fountzoulas; B A Cheeseman; J C LaSalvia; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The present investigation is a continuation of our previous study on the ability of the phenomenological Johnson-Holmquist model to predict the observed damage induced by spheres of tungsten carbide (WC) striking confined cylinders of silicon carbide (SiC) at velocities between 63 m/s to 500 m/s. In this study, the WC was modeled using the Johnson-Cook plasticity model along with a principal stress failure criterion calibrated with recently available experimental data. ... |
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| Ballistics Filtering |
Mar-2009 |
36 pages |
| Authors:
Andrew A Thompson; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| There are many models of ballistics trajectories. The high-resolution 6-degree-of-freedom (6-DOF) models require many computations and a small time increment. The modified point mass models ignore the spinning of the round to reduce the computational requirements. Selecting a model to use for ballistics estimation or tracking requires tradeoffs between system accuracy and computation expense. The purpose of this report is to present reduced state models (simpler than the 6-DOF model) ... |
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| Damage Assessment of a Small Spherical Projectile Impacting on a Glass Shield |
Jan-2009 |
10 pages |
| Authors:
James M Sands; Jian H Yu; Peter G Dehmer; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| A high-speed photographic method was set up to track a small projectile in flight and capture its subsequent impact on a glass shield. A 1.0-mm-diameter steel ball bearing was launched from a compressed helium gas gun. The flight of the projectile and the impact event were captured with high-speed cameras. The glass shield showed visible damage at an impact speed of more than 205 m/s. |
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| Transition Delay in Hypervelocity Boundary Layers by Means of CO2/Acoustic Instability Interactions |
08-Dec-2008 |
52 pages |
| Authors:
Graham Candler; Ivett A Leyva; Stuart Laurence; Amy W Beierholm; Hans G Hornung; Ross Wagnild; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A novel method to delay transition in hypervelocity flows over slender bodies by injecting CO2 into the boundary layer of interest is investigated. The results presented here consist of both experimental and computational data. The experimental data was obtained at Caltech's T5 reflected shock tunnel, while the computational data was obtained at the University of Minnesota. The experimental model was a 5 degree sharp cone, chosen because of its relevance ... |
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| Kennislacunes op het gebied van wapens en munitie in OVG (Knowledge Gaps in the Area of Weapons and Munitions in MOUT) |
Dec-2008 |
|
| Authors:
J J Paulissen; Th L Verhagen; TNO DEFENCE SECURITY AND SAFETY RIJSWIJK (NETHERLANDS)
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 | The urban environment is one of the most difficult mission areas for the warfighter. The purpose of this study is to characterize the effects of weapons and munitions in the context of Military Operations in Urban Terrain (MOUT), and to identify associated knowledge gaps. The result is an overview of current knowledge gaps and an approach for addressing these gaps in future research. |
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| Enhanced Fragmentation Modeling |
Dec-2008 |
5 pages |
| Authors:
William Ng; Richard Fong; Peter Rottinger; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
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| Enhancing the fragmentation capability of current and future projectiles is critical to meeting the armies Future Combat Systems, FCS, requirements. In order to meet these requirements, enhancements to the fragmentation capabilities of these future weapons is needed. Only through the use of the latest modeling tools can these goals be achieved. The U.S. Army Armament Research and Development Center, ARDEC, has continued its efforts to develop its modeling capabilities further ... |
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| Effect of Projectile Type, Size and Impact Velocity on Ballistic Impact Failure Behavior of TROGAMID CX-7323 Nylon |
Dec-2008 |
8 pages |
| Authors:
Nicholas Tsantinis; John W Song; ARMY NATICK SOLDIER RESEARCH DEVELOPMENT AND ENGINEERING CENTER MA
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| Extensive study on the fracture behavior of TROGAMID CX-7323 (CX-7323) nylon under ballistic impact was performed. Generally, CX-7323 exhibits ductile failure upon impact with a 17-grain fragment simulating projectile(s) (FSP). Penetration is initiated by ductile shearing upon impact. Subsequent tensile stretching allows the penetration event to progress. Material in front of the projectile is pushed out of the way during penetration. Significant elastic recovery of the exit hole is noticed ... |
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| Continuum Model Simulations and Experiments of Projectile Impact on Woven Fabric |
Dec-2008 |
|
| Authors:
Tusit Weerasooriya; Ethan M Parsons; Simona Socrate; Sai Sarva; MASSACHUSETTS INST OF TECH CAMBRIDGE
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| Modeling woven fabrics is challenging due to the need to capture the fabric response at both the macroscopic scale of the fabric and the mesoscale of the yarns that compose the weave. Here, we utilize a continuum-level modeling technique for woven fabrics which captures the macroscopic response of the fabric as well as the evolution of its mesostructure with deformation in a single efficient modeling step. A membrane element formulation ... |
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| Computer Simulation of a 155-mm Projectile in a Scat Gun Assembly |
01-Sep-2008 |
34 pages |
| Authors:
Kenneth P Walsh; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
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| This report presents the results of a computer simulation of a 45.36 kg 155-mm projectile as it moves through a scat gun assembly using a FORTRAN program. The experimental data was taken from a test performed by the Analysis Engineering and Technical Division at the U.S. Army Armament Research, Development and Engineering Center, Picatinny Arsenal, New Jersey on 7 April 2007 (test CBR5). The data was filtered using an Abaqus ... |
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| Control Mechanism Strategies for Spin-Stabilized Projectiles |
Sep-2008 |
34 pages |
| Authors:
Frank Fresconi; Peter Plostins; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Spin-stabilized artillery munitions were originally designed to provide precise ballistic fire on long-range targets. Today the challenge is to utilize these ballistic munitions in military operations in urban terrain environments where significantly higher levels of precision are required to minimize collateral damage. One strategy is to retrofit these munitions with some level of low-cost precision. Unique challenges arise when munitions designed to be ballistically precise are guided. Projectile flight is ... |
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| Investigation of Small-Caliber Primer Function Using a Multiphase Computational Model |
01-Jul-2008 |
36 pages |
| Authors:
John R Schmidt; Michael J Nusca; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| This report describes further development in the formulation of a primer model that is compatible with the ARL-NGEN3 code and small caliber weapons that takes in account multidimensional, multiphase interior ballistics codes, which employ coupled Eulerian-Lagrangian schemes to explicitly treat both the gas and solid phase. The model is based on the One Dimensional Turbulence modeling approach that has recently emerged as a powerful tool in multiphase simulations. Initial results ... |
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| Benefits of Steeper Angle of Fall for Precision Projectiles |
Jun-2008 |
16 pages |
| Authors:
Jon Peoble; James Rodrigue; RAYTHEON MISSILE SYSTEMS CO TUCSON AZ
|
| Background and Study Objective: Background -Battlefield has changed since initial requirements for precision projectiles were developed: - Counterinsurgency vs. Mobile Armored Warfare - Combat among the population vs. on unoccupied terrain - Collateral Damage relationship to strategic outcome -FA is again relevant: cannon-delivered precision fires have been achieved, demonstrated in combat, and early expectations surpassed -Requirements have not yet reflected technology capability for AOF. Study Objective: -Quantify benefits of having ... |
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| Re-Visiting 1-D Hypervelocity Penetration (Preprint) |
01-Apr-2008 |
13 pages |
| Authors:
David E Lambert; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
|
| Classical, one-dimensional theory of hydrodynamic penetration is used as the basis of establishing simplified analytical relationships describing energy, momentum, and power deposition during hypervelocity impact events. A concise overview of the 1-D model is given followed by a select grouping of terms into relationships that offer first-order criteria for making engineering design considerations on relevant applications and assist in the analysis of experimental observations. Momentum, energy, and power deposition are ... |
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| Analysis of Multi-Layered Materials Under High Velocity Impact Using CTH |
01-Mar-2008 |
198 pages |
| Authors:
Jason K Lee; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| Multi-layer armor containing ceramic and metallic layers has become more common in the past two decades. Typically, ceramics have high compressive strength; that feature combined with their low density make them highly desirable for armor applications. This research effort numerically simulates ballistic impact of a cylindrical penetrator with a hemispherical tip on multi-layer metallic and ceramic targets of finite thickness. The projectile is made of S7 tool steel, while the ... |
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| Computational Simulation of High-Speed Projectiles in Air, Water, and Sand |
03 DEC 2007 |
34 pages |
| Authors:
Jack R. Edwards; NORTH CAROLINA STATE UNIV AT RALEIGH
|
| The development of a comprehensive computational fluid dynamics approach for conducting simulations of projectile penetration into water-saturated sand is reported. High resolution upwind schemes suitable for a fluid dynamic system consisting of gas, liquid, and dispersed solids phases are derived and are combined with a time-derivative preconditioning strategy for efficient time integration at all flow speeds. A solids-stress model based on Mohr-Coulomb critical-state theory is used to account for compaction ... |
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| An Analysis of Magnesium Alloy AZ31B-H24 for Ballistic Applications |
DEC 2007 |
20 pages |
| Authors:
Tyrone L. Jones; Matthew S. Burkins; William A. Gooch; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The U.S. Army Research Laboratory is developing a ballistic specification for the use of magnesium alloy AZ31B-H24 as armor on Army platforms. Data were generated for a range of thicknesses of this magnesium alloy, 0.25 to 4 inches, with the use of five different projectiles. The magnesium performance is parametrically quantified on an equivalent areal density to meet the aluminum alloy 5083-H131, which means a mature, well defined, low-density metal. ... |
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| Software Development for Automation of Space- and Time- Varying Pressurization on Small Caliber Gun Barrels |
AUG 2007 |
28 pages |
| Authors:
Michael M. Chen; Joseph T. South; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| A console application program was developed to automate the process, starting from triggering IBHVG2 (Interior Ballistics of High Velocity Guns, version 2) execution on the fly for pressure calculation, determining pressure gradient along down-bore distance, parsing the LS-DYNA(TM) key word file for element extraction, associating load curves with selected elements, and finally generating a complete LS-DYNA key word file for explicit dynamic analysis. This report presents the architecture and process ... |
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| Impact Response of Sandwich Plates with a Pyramidal Lattice Core |
20-Jul-2007 |
18 pages |
| Authors:
Haydn N Wadley; Christian J Yungwirth; John H O'Connor; Alan J Zakraysek; Vikram S Deshpande; VIRGINIA UNIV CHARLOTTESVILLE DEPT OF MATERIALS SCIENCE AND ENGINEERING
|
| The ballistic performance edge clamped 304 stainless-steel sandwich panels has been measured by impacting the plates at mid-span with a spherical steel projectile whose impact velocity ranged from 250 to 1300 ms(-1). The sandwich plates comprised two identical face sheets and a pyramidal truss core: the diameter of the impacting spherical projectile was approximately half the 25 mm truss core cell size. The ballistic behavior has been compared with monolithic ... |
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| Analysis of Shock and High-Rate Data for Ceramics: Strength and Failure of Brittle Solids |
JUL 2007 |
48 pages |
| Authors:
Dennis E. Grady; APPLIED RESEARCH ASSOCIATES INC ALBUQUERQUE NM
|
| Ceramics based on composition of the light intermetallic compounds, have demonstrated considerable success as a barrier material in armor applications. The exceptional strength-to-density ratio of ceramic plays a crucial role in the positive performance of ceramics in the terminal ballistic environment. Even the higher density ceramics, such as tungsten based materials, show promising behavior in space-limited armor applications. The implementation, optimization and evaluation of ceramic in armor systems benefit from ... |
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| Ballistic Testing of Australian Bisalloy Steel for Armor Applications |
JUN 2007 |
18 pages |
| Authors:
Dwight D. Showalter; William A. Gooch; Matt S. Burkins; Victoria Thorn; Stephen J. Cimpoeru; Russell Barnett; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The U.S. Army Research Laboratory (ARL) and Australian Defense Science and Technology Organization (DSTO) have ballistically baselined a range of armor steels (277-321HB to 477-534HB) manufactured by the Australian company, Bisalloy Steels. Plate was tested in thicknesses from 10 mm to 20 mm and ARL and DSTO ballistically tested the plates against 0.30 caliber and 0.50 caliber armor piercing projectiles, 0.50 caliber and 20 mm Fragment Simulating Projectiles (FSPs) and ... |
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| Response Surface Mapping Technique Aids Warfighters |
MAY 2007 |
5 pages |
| Authors:
Bruce C. Patterson; AIR FORCE RESEARCH LAB EGLIN AFB FL MUNITIONS DIRECTORATE
|
| Scientists apply innovative data mining and visualization techniques to real-world weapon penetration mechanics problems. |
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| Modeling Damage and Fragmentation in Concrete |
APR 2007 |
22 pages |
| Authors:
John D. Clayton; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| A theory combining nonlinear continuum elasticity, inelasticity, thermodynamics, damage mechanics, and fragmentation is formulated. The model is applied to study concrete subjected to high rate loading as occurs during ballistic impact. Two thermodynamically motivated methods are postulated within this theoretical framework for quantitatively characterizing the mass and velocity distributions of the post-impact debris field, one based upon a local energy balance and a second following global entropy maximization. Here the ... |
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| Ballistic Evaluation of Magnesium Alloy AZ31B |
APR 2007 |
20 pages |
| Authors:
Tyrone L. Jones; Richard D. DeLorme; Matthew S. Burkins; William A. Gooch; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Wrought magnesium alloys, which maintain various niche market applications because of their unique properties, have been the subject of a heightened level of research and development for potential application in the automotive market; however, few data are available about their ballistic properties. In order to fill this gap, the U.S. Army Research Laboratory (ARL) and Magnesium Elektron North America (MENA), Inc., conducted a cooperative effort to evaluate magnesium alloy AZ31B, ... |
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| Engineering Model for Design of Explosive Fragmentation Munitions |
FEB 2007 |
21 pages |
| Authors:
Vladimir M. Gold; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
|
| An engineering model for design of explosive fragmentation munitions presented in this work is based on integrating three-dimensional axisymmetric hydrocode analyses with analyses from a newly developed fragmentation computer code MOTT. The validation of the MOTT code fragmentation model was accomplished using the existing munition arena test data. After having established the crucial parameters of the model, a new explosive fragmentation munitions was designed and optimized. Upon fabrication of the ... |
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| Analysis of Behind-Armor Debris Fragments From Physics-Based Simulations |
FEB 2007 |
18 pages |
| Authors:
Jerry A. Clarke; Hubert W. Meyer; Eric R. Mark; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The multimaterial, large deformation, strong shock wave, solid mechanics code CTH is heavily used for armor penetration applications. It would be extremely beneficial to use this type of physics-based simulation to produce a realistic behind-armor debris field as input to survivability and lethality codes. Utilizing the capabilities of the interdisciplinary computing environment, we have developed a tool that is capable of identifying individual fragments in a CTH flat mesh or ... |
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| Ballistic Missile Trajectory Estimation |
DEC 2006 |
77 pages |
| Authors:
Joseph Dituri; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Angles measurements from optical systems are the primary source of data for maintaining the orbits of high altitude satellites. Radar measurements are used primarily for low Earth orbit (LEO) satellites. Recently it has been shown that the accuracy of the orbit updates using only optical system angles-only data is just as good, if not better, than the performance from radar systems for LEO satellites. The purpose of this thesis is ... |
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| Development of an Artillery Accuracy Model |
DEC 2006 |
113 pages |
| Authors:
Chee M. Fann; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF MECHANICAL AND ASTRONAUTICAL ENGINEERING
|
| This thesis explains the methodologies that predict the trajectory and accuracy of an unguided, indirect-fire launched projectile in predicted fire. The trajectory is the path that a projectile travels to the impact point, while the accuracy is the measurement of the deviation of the impact point from the target. In addition, this thesis describes, the methodology for calculating the various factors such as drag and drift in the trajectory calculation. ... |
|
| Sustainability of Rotrode Atomic Emission Spectrometry for Wear Deris |
04 OCT 2006 |
32 pages |
| Authors:
Edward T. Urbansky; JOINT OIL ANALYSIS PROGRAM PENSACOLA FL TECHNICAL SUPPORT CENTER
|
| Analysis of oil for wear debris by rotrode atomic emission spectrometry (RAES) has been part of the component health monitoring used by the military services for two decades. However, the last 5 10 years have seen a number of changes, including attrition from the program, more serious budgetary constraints, improvements in the design and manufacturing of engines and other components, and changes in oil filtration. Although the need for diagnostic ... |
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| Small-Caliber Projectile Target Impact Angle Determined From Close Proximity Radiographs |
OCT 2006 |
50 pages |
| Authors:
Tyler E. Ehlers; Bernard J. Guidos; David W. Webb; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Small-caliber rounds have a yaw cycle of approximately three meters, but the magnitude and initial yaw varies from shot to shot, even when fired from the same gun. This yaw cycle becomes a variable that researchers must consider when looking at the lethality of an individual shot and round type, especially when testing at close ranges where the yaw cycle is high. Four orthogonal radiograph images provided measured pairs of ... |
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| Multiscale Mechanical Characterization of Biomimetic Physically Associating Gels |
SEP 2006 |
16 pages |
| Authors:
Thomas F. Juliano; Aaron M. Forster; Peter L. Drzal; Tusit Weerasooriya; Paul Moy; Mark R. VanLandingham; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| The mechanical response of living tissue is important to understanding the injury-risk associated with impact events. Often, ballistic gelatin or synthetic materials are developed to serve as tissue surrogates in mechanical testing. Unfortunately, current materials are not optimal and present several experimental challenges. Bulk measurement techniques, such as compression and shear testing geometries, do not fully represent the stress states and rate of loading experienced in an actual impact event. ... |
|
| Dynamic Response of an Alternative Tissue Simulant, Physically Associating Gels (PAG) |
SEP 2006 |
14 pages |
| Authors:
Paul Moy; Tusit Weerasooriya; Thomas F. Juliano; Mark R. VanLandingham; Wayne Chen; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Recent work on formulating alternatives to ballistic gelatin, a soft tissue simulant, has lead to the development of physically associating gels (PAG). Ballistic gelatin impact response has been traditionally used to test and evaluate firearms and bullets but it does have some drawbacks, such as lacking consistency in its viscoelastic properties due to variability during the fabrication process, short shelf-life, and deterioration under prolonged usage at room temperature. PAG offers ... |
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| Efficient Calculation of Earth Penetrating Projectile Trajectories |
SEP 2006 |
119 pages |
| Authors:
Daniel F. Youch; NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF MECHANICAL AND ASTRONAUTICAL ENGINEERING
|
| Currently, two methods exist to determine trajectory of a ballistic penetrator: Poncelet Analysis and Differential Area Force Law (DAFL) methods. An exact solution for the Poncelet Equation exists; making for easy computation. However, the one dimensional nature of the equation fails to capture the intricate three-dimensional nature of real world ballistic penetrator trajectories. The DAFL methods employ empirically derived stress algorithms to calculate the forces acting on a differential area ... |
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| Generating an Aerodynamic Model for Projectile Flight Simulation Using Unsteady, Time Accurate Computational Fluid Dynamic Results |
SEP 2006 |
34 pages |
| Authors:
Joseph Kokes; Mark Costello; Jubaraj Sahu; OREGON STATE UNIV CORVALLIS
|
| A method to efficiently generate a complete aerodynamic description for projectile flight dynamic modeling is described. At the core of the method is an unsteady, time accurate computational fluid dynamics simulation that is tightly coupled to a rigid body dynamics simulation. A set of n short time snippets of simulated projectile motion at m different Mach numbers is computed and employed as baseline data. For each time snippet, aerodynamic forces ... |
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| Application of Computational Fluid Dynamics to a Preliminary Extended Area Protection System (EAPS) Projectile |
SEP 2006 |
30 pages |
| Authors:
Karen Heavey; Jubaraj Sahu; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Computational fluid dynamics approaches were used to compute the flow fields and aerodynamic forces and moments of a slender-body finned projectile. Steady-state numerical results have been obtained for a series of cases, with Mach numbers ranging from 1.5 to 5.0 and at angles of attack from 0 deg to 5 deg. Full three-dimensional computations were performed using a cubic k-epsilon turbulence model. In general, the computed aerodynamic coefficients compared well ... |
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| Progress in the Development of a Multiphase Turbulent Model of the Gas/Particle Flow in a Small-Caliber Ammunition Primer |
AUG 2006 |
44 pages |
| Authors:
John R. Schmidt; Michael J. Nusca; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| There is significant experimental evidence that burning particles of various chemical compositions and sizes are ejected from gun primers and that these particles interact with the propellant grains during main charge ignition. This explicit ignition phenomenon is thought to be incompatible with the implicit treatment of primer function in conventional interior ballistics codes and models. Generally, the primer efflux is treated as a hot gas that evolves from a specified ... |
|
| A Comparison of the Deformation Flow and Failure of Two Tungsten Heavy Alloys in Ballistic Impacts |
MAY 2006 |
16 pages |
| Authors:
Brian E. Schuster; Bryan P. Peterson; Lee S. Magness; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Ballistic tests were conducted with sub-scale long rod penetrators of two different processing conditions of the same tungsten heavy alloy. The liquid-phase sintered composite of 90% tungsten-9% nickel-1% cobalt (by weight) was tested in its low strength, as-sintered and heat-treated condition, and in a high strength, 50% cold-worked (by swaging) and aged condition. Small, but consistent, differences in the ballistic performances of the two lots of penetrators were observed in ... |
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| The Charge Designer's Workbench: A Range of Interior Ballistic Modeling Tools |
MAY 2006 |
24 pages |
| Authors:
Albert W. Horst; Michael J. Nusca; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Gun and ammunition designers typically employ various models initially to evaluate preliminary design concepts and ultimately to make specific decisions regarding the design and optimization of both individual components and all-up weapon systems. A wide range of computerized models exists today to address virtually every aspect of this process; in particular, the propelling charge designer has available several levels of interior ballistic models. These range from rather simple lumped-parameter models, ... |
|
| Lightweight Multifunctional Linear Cellular Alloy Ballistic Structures |
26 APR 2006 |
16 pages |
| Authors:
Joe K. Cochran; STRUCTURED ALLOYS INC MARIETTA GA
|
| The objective of this effort was to develop the techniques for fabricating a multifunctional lightweight structure that could be used as armor for mobile vehicles such as personnel carriers. These fabrication techniques are scalable to manufacturing production levels. For this program, square cell LCA honeycomb with both maraging steel and super invar compositions were fabricated using SAI's patented technology to have cross sections of one inch square. These honeycombs have ... |
|
| Improve Ballistic Test and Evaluation Methodology |
APR 2006 |
19 pages |
| Authors:
Shane Sullivan; John Halstead; MILITARY ACADEMY WEST POINT NY OPERATIONS RESEARCH CENTER
|
| Ballistic test and evaluation of body armor is of great priority for the US Army to meet current operational needs. The current experimental design process centers on standardized threat level classifications and a baseline ballistic limit velocity, V50; both measures originate from the National Institute of Justice circa 1979. The measures are complex, statistical in nature, and yield large quantities of data. A methodology incorporating response surface techniques improves ballistic ... |
|
| Modeling Plasma Flow in Solid Propellant Charges Using the NGEN Multiphase CFD Code |
APR 2006 |
34 pages |
| Authors:
Michael J. Nusca; Stephen L. Howard; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Recent requirements for hypervelocity projectile launch for strategic U.S. Army missions have led to the proposal of a variety of gun propulsion systems. Among these systems are those that utilize solid propellant along with electrothermal-chemical (ETC) augmentation. Advanced solid propellant systems with complex grain geometry and loading configuration are also being investigated. In response to this need, the U.S. Army Research Laboratory, in cooperation with Paul Gough Associates, is developing ... |
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| IBHVG2: Mortar Simulation With Interior Propellant Canister |
MAR 2006 |
73 pages |
| Authors:
Ronald D. Anderson; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| A method has been implemented for the Interior Ballistics of High Velocity Guns, Version 2 (IBHVG2) simulation program to model mortar systems, including an enclosed high-pressure igniter canister. The application allows initial pressurization of the canister until interior pressure reaches a force high enough to rupture a burst diaphragm. Combustion gases are then released to the larger (main) chamber to accelerate the projectile or to ignite additional propellant for the ... |
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| Infrasound Modeling Using Soviet Explosion Data and Instrument Design Criteria from Experiments and Simulations |
FEB 2006 |
70 pages |
| Authors:
Jeffry L. Stevens; David A. Adams; G. E. Baker; Heming Xu; John R. Murphy; igor Divnov; Vadim N. Bourchik; TITAN CORP SAN LEANDRO CA PULSE SCIENCES DIV
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| This report covers two major topics: evaluation of International Monitoring System (IMS) network performance using data from historic Soviet nuclear tests and analysis of infrasound instrumentation design. The Institute for the Dynamics of the Geospheres has digitized 220 infrasound waveforms from 22 atmospheric nuclear tests conducted in 1961. We compare measurements from this data set with infrasound scaling and attenuation relations and find best agreement with a relation developed by ... |
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| Ballistic Imaging in the Primary Breakup Region of Diesel Injector Sprays |
31 JAN 2006 |
16 pages |
| Authors:
M. A. Linne; T. E. Parker; COLORADO SCHOOL OF MINES GOLDEN
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| The Colorado School of Mines (CSM) has developed a technique (called ballistic imaging) for single-shot imaging of the near-field primary breakup region of a diesel spray. Ballistic imaging is a non-intrusive optical measurement technique that produces line-of-sight integrated images. These images represent the underlying spray structure in spite of the droplet cloud which surrounds the interior of the spray. Single shot ballistic imaging relies on an ultra-fast optical switch; the ... |
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Ballistics
