2019 15th Hypervelocity Impact Symposium最新文献

{"title":"Optimized Impact Mitigation Barriers for Insensitive Munitions Compliance of a 120mm Warhead","authors":"K. Miers, Daniel L. Prillaman, N. Al-Shehab","doi":"10.1115/hvis2019-105","DOIUrl":"https://doi.org/10.1115/hvis2019-105","url":null,"abstract":"\u0000 The U.S. Army Combat Capabilities Development Command (CCDC) Armaments Center at Picatinny Arsenal, NJ is working to develop technologies to mitigate the violent reaction of a 120 mm warhead, loaded with an aluminized HMX-based enhanced blast explosive, when subjected to the NATO Insensitive Munitions (IM) Fragment Impact (FI) test. As per NATO STANAG 4496, FI testing is conducted at 8300±300 ft/s with a 0.563” diameter, L/D~1, 160˚ conical nosed mild steel fragment. Reaction violence resulting from FI can be mitigated by the use of liners or barriers applied to the munition itself or its packaging, commonly referred to as a Particle Impact Mitigation Sleeves (PIMS). Previous development efforts for this item focused on a lightweight plastic warhead support which was able to reduce the severity of the input shock sufficiently to prevent high order detonation. However, violent sub-detonative responses were still observed which occurred over several hundred microseconds, consumed part of the explosive charge, and ejected hazardous debris over large distances. These responses are driven by rapid combustion coupled with damage to the explosive as well as mechanical confinement. Quantitative modeling of these scenarios is a challenging active research area. Prior experimental results and modeling guidance have shown that mitigation of these reactions requires a more substantial reduction in the overall mechanical insult to the explosive. In particular, steel and aluminum PIMS have been able to efficiently provide the necessary fragment velocity reduction, breakup and dispersion in typical packaging applications. Packaged warheads were tested at the GD-OTS Rock Hill facility with several PIMS designs incorporated into the ammunition containers. Several designs were demonstrated to provide benign reactions with minimal added weight. Future iterations will attempt to further improve the design using advanced lightweight barrier materials.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74087331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Explosion of hydrazine tanks due to space debris impacts","authors":"J. Limido, C. Puillet, J. Vila","doi":"10.1115/hvis2019-099","DOIUrl":"https://doi.org/10.1115/hvis2019-099","url":null,"abstract":"\u0000 The impact of space debris on a spacecraft can result in a catastrophic event that not only destroys the structure but can also create more space debris. The design of any spacecraft requires understanding the potential damage that can be inflicted by such an event. We consider the case of a satellite hydrazine fuel tank and the consequences of a hypervelocity impact from space debris. The purpose of this study is to better understand the mechanisms of detonation of hydrazine vapor during a hypervelocity impact on a low-pressure reservoir. The IMPETUS Afea Solver® and Explo5 software were used to perform numerical simulations of operational impact configurations (v = 14 km / s). The multi-scale calculations are performed using the Next Generation IMPETUS ɣSPH solver. A numerical assessment of the impact performance at the scale of the reactive fluid reservoir representative of a real configuration (global and local scale) was carried out. The model includes the detonation in the fluid and the transfer of the momentum to the structure which includes capturing the perforation of the structure that results from the explosive loading. A first diagram (impact velocity, diameter / perforation-explosion) was constructed on a reference tank of diameter 50cm and thickness 1mm in titanium.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"67 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76067534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the ballistic properties of ejecta from laser shock-loaded samples using high resolution picosecond imaging","authors":"A. Sollier, E. Lescoute","doi":"10.1115/hvis2019-097","DOIUrl":"https://doi.org/10.1115/hvis2019-097","url":null,"abstract":"\u0000 Anticipating the generation of high velocity debris from shock-loaded specimens and the damage that their impacts may cause to nearby equipment is a major safety issue in applications involving shock waves, such as pyrotechnics [1] or inertial confinement fusion (ICF) experiments on large scale laser facilities [2]. Microjetting is one of the processes governing such debris generation. It is due to the interaction of a shock wave with a free surface presenting geometrical defects such as pits, cavities, scratches, or grooves, leading to material ejection from these defects, in the form of thin jets expanding ahead of the main surface and breaking up into small particles [3]. Over the last few years, we have used laser shock loading in order to expand microjetting investigations over ranges of small spatial scales (μm scale), extremely high loading rates (~ 107 s-1) and very short pressure pulses (a few ns) [4-11]. Optical shadowgraphy and Photonic Doppler Velocimetry (PDV) have been used to measure both jet tip and planar surface velocities [4-6], while attempts to infer fragments size distributions, to be compared with model predictions, have been made using either fast transverse shadowgraphy [7] or ejecta recovery [8]. More recently, picosecond x-ray radiography has been used to provide estimates of the density gradients along the jets and of the total ejected mass at different times after shock breakout [9-11]. Here, we present the development of a new picosecond laser imaging diagnostic intended to overcome the limitations of our current transverse optical shadowgraphy setup. We describe our experimental setup and show the results of our first experiments performed using both visible (532 nm) and UV (355 nm) lightning of the sample. These results are compared to those obtained at LANL under high explosive loading using ultraviolet in-line Fraunhofer holography [12], and also to molecular dynamics (MD) simulations performed by our colleagues at lower space and time scales [15-18].","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89234790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling the deformation of a high-hardness armour steel in Taylor rod-on-anvil experiments","authors":"S. Ryan, B. Mcdonald, N. Scott, R. Bigger, S. Chocron","doi":"10.1115/hvis2019-040","DOIUrl":"https://doi.org/10.1115/hvis2019-040","url":null,"abstract":"\u0000 A high hardness armour steel (HHA) has been subjected to mechanical characterization under tension, compression, and shear loading at quasi-static and dynamic rates incorporating ambient and elevated temperatures. The resulting data has been used to derive constants for four plasticity constitutive models: Johnson-Cook (JC), Zerilli-Armstrong (ZA), modified Johnson-Cook (MJC), and a generalized J2-J3 yield surface (GYS). The resulting models have been used to predict the response of the HHA material during Taylor rod-on-anvil experiments. High speed photography and digital image correlation was used during the rod-on-anvil experiments to capture both transient deformation profiles and maximum principal strain along the surface of the rod (i.e. compression along the length of the rod). The JC, MJC, and GYS models were found to provide the best prediction of the shape of the rod (nose diameter and length), within 2% of the experimental measurement in all four rod-on-anvil experiments which did not result in fracture. The JC and GYS models, furthermore, were found to provide the best agreement with the measured transient surface strain profiles, predicting the experimental measurement to within 10% at all measurement locations and time steps for the experiment resulting in maximum deformation (impact velocity = 208 m/s). The results suggest that the added complexity of models such as the MJC and GYS, which incorporate strain hardening saturation, two-part strain rate dependency, and J3 plasticity effects, are unnecessary for HHA under the loading conditions experienced during rod-on-anvil experiments.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90657216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D Printed Conical Shaped Charge Performance","authors":"P. Mulligan, C. Johnson, Jason Ho, C. Lough, E. Kinzel","doi":"10.1115/hvis2019-110","DOIUrl":"https://doi.org/10.1115/hvis2019-110","url":null,"abstract":"\u0000 A Conical Shaped Charge (CSC) is a versatile device utilized in construction, mining, petroleum and defense industries. The geometry and material structure of the metal liner play an integral role in the CSC performance. The performance of CSC liners has been relatively well-characterized for liners manufactured via hydroforming, hydraulic pressing, or turning on a CNC lathe. With advancements in Additive Manufacturing (AM) CSC liners can be 3D printed with metal powders. AM can provide significant design freedom in terms of realizing better properties through introduced hierarchic structuring or anisotropy. However, it is unclear as to how metal liners produced with Selective Laser Melting (SLM), will influence the conical shaped charge’s performance. This paper explores the performance, relative to the penetration of steel plates, of CSCs using 3D printed metal liners benchmarked against machined liners. The metal liners were printed with SLM parameters that were optimized to maximize the print density. The metal liner dimensions (thickness, height, and outer diameter) were designed using the recommended ratios of the liner’s inner diameter presented by Virgil (1988). The 3D printed metal liners are compared to a CNC machined liner, with the same dimensions. The comparison enables the evaluation of how 3D printing a liner influences penetration performance. The results indicate conical shaped charges could utilize 3D printed liners. These results open a wide range of performance design opportunities that cannot be achieved via conventional manufacturing and justify the current increased cost associated with additive manufacturing metal components. Future work will continue to explore how print density, printed material, and advanced geometries modify the conical shaped charge performance.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82279668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defeating Modern Armor and Protection Systems","authors":"M. Graswald, R. Gutser, Jakob Breiner, F. Grabner, T. Lehmann, Andrea Oelerich","doi":"10.1115/hvis2019-050","DOIUrl":"https://doi.org/10.1115/hvis2019-050","url":null,"abstract":"\u0000 An open source research and vulnerability study of main battle tanks and their protections systems revealed that current anti-tank weapons may not be suited to defeat modern threats. One example is the novel T-14 tank being developed and tested in the Russian army with its combined hard-kill and soft-kill active protection system AFGANIT / SHTORA, its new reactive armor MALACHIT as well as improved multi-component passive armor. Additionally, modern active protection systems currently developed in, e.g., Israel, the United States, and Germany feature also multi-sensor and multi-effector systems with drastically improved detection and intercept ranges, short system reaction times as well as protection against multiple threats attacking simultaneously and / or from similar directions. While known effectors and concepts may overcome fielded active protections systems, they are probably not suited in defeating such modern and even future systems. Countermeasures relying on high engagement velocities through improved kinetic energy projectiles or hypervelocity penetrators may provide a potential solution. Another promising concept generates directed, far-distance electromagnetic effects defeating sensors and communications systems of modern main battle tanks. After such a mission kill, a following salvo attack through an anti-tank or modern multi-role weapon will eventually lead to a catastrophic kill. Feasibility studies of these mobile electromagnetic effectors have already shown their high potential.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86684551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shear band characteristics in high strain rate naval applications","authors":"M. Conway, J. Hogan","doi":"10.1115/hvis2019-051","DOIUrl":"https://doi.org/10.1115/hvis2019-051","url":null,"abstract":"\u0000 This paper explores the dynamic behavior of HSLA 65 naval steels, specifically focusing on the initiation and growth of shear bands in quasi-static and dynamic compression experiments and how these bands affect stress-strain responses. The results indicate that the yield strength for this HSLA 65 increases from 541 ± 8 MPa for quasi-static (10-3 s-1) to 1081 ± 48 MPa for dynamic rates 1853 ± 31 s-1, and the hardening exponent increases from 0.376 ± 0.028 for quasi-static to 0.396 ± 0.006 for dynamic rates. Yield behavior was found to be associated with the onset of shear banding for both strain-rates, confirmed through visualization of the specimen surface using high-speed and ultra-high-speed cameras. For the quasi-static case, shear banding and yielding was observed to occur at 2.5% strain, and were observed to grow at speeds of upwards of 38 mm/s. For the dynamic experiments, the shear banding begins at approximately 1.18 ± 0.06% strain and these can grow upwards of 2122 ± 213 m/s during post-yield softening. Altogether, these measurements are some of the first of their kind in the open literature, and provide guidance on the critical time and length scales in shear banding. This information can be used in the future to design more failure-resistant steels, which has broader applications in construction, defense, and natural resource industries.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86277256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Updates to the DebriSat Project in Support of Improving Breakup Models and Orbital Debris Risk Assessments","authors":"H. Cowardin, P. Anz-meador, J. Murray, J. Liou, E. Christiansen, M. Sorge, N. Fitz-Coy, T. Huynh","doi":"10.1115/hvis2019-066","DOIUrl":"https://doi.org/10.1115/hvis2019-066","url":null,"abstract":"\u0000 Existing DOD and NASA satellite breakup models are based on a key laboratory test, the 1992 Satellite Orbital debris Characterization Impact Test (SOCIT), which has supported many applications and matched on-orbit events involving older satellite designs reasonably well over the years. To update and improve these models, the NASA Orbital Debris Program Office, in collaboration with the Air Force Space and Missile Systems Center, The Aerospace Corporation, and the University of Florida, conducted a hypervelocity impact test using a high-fidelity mock-up satellite, DebriSat, in controlled and instrumented laboratory conditions. DebriSat is representative of present-day LEO satellites, having been constructed with modern spacecraft materials and techniques. The DebriSat fragment ensemble provided a variety of shapes, bulk densities, and dimensions. Fragments down to 2 mm in size are being characterized by their physical and derived properties. A subset of fragments will be analyzed further in laboratory radar and optical facilities to update the existing radar-based NASA Size Estimation Model (SEM) and develop a comparable optical-based SEM. Thoroughly understanding size estimates from ground-based optical and radar sensors is one of the key parameters used in assessing the environment and the risks that debris present to operational spacecraft. The data will inform updates to the current NASA Standard Satellite Breakup Model (SSBM);, which was formulated using laboratory and ground-based measurements of on-orbit fragmentation events to describe an average breakup for spacecraft and upper stage collisions and explosions. DebriSat will extend the laboratory data ensemble. The DebriSat shape and density categories provide a baseline for non-spherical projectile hypervelocity impact testing for damage assessment. The data from these tests, simulations, and analyses will be used to update the NASA Orbital Debris Engineering Model (ORDEM) with more realistic simulations of catastrophic fragmentation events for modern satellites and to assess the risk posed by the orbital debris environment. This paper provides an overview of the project, updates on the characterization process, and the NASA analysis status.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84326375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Accurate SPH Scheme for Hypervelocity Impact Modeling","authors":"A. Collé, J. Limido, T. Unfer, J. Vila","doi":"10.1115/hvis2019-078","DOIUrl":"https://doi.org/10.1115/hvis2019-078","url":null,"abstract":"\u0000 We focus in this paper on the use of a meshless numerical method called Smooth Particle Hydrodynamics (SPH), to solve fragmentation issues as Hyper Velocity Impact (HVI). Contrary to classical grid-based methods, SPH does not need any opening criteria which makes it naturally well suited to handle material failure. Nevertheless, SPH schemes suffer from well-known instabilities questioning their accuracy and activating nonphysical processes as numerical fragmentation. Many stabilizing tools are available in the literature based for instance on dissipative terms, artificial repulsive forces, stress points or Particle Shifting Techniques (PST). However, they either raise conservation and consistency issues, or drastically increase the computation times. It limits then their effectiveness as well as their industrial application. To achieve robust and consistent stabilization, we propose an alternative scheme called γ -SPH-ALE. Firstly implemented to solve Monophasic Barotropic flows, it is secondly extended to the solid dynamics. Particularly, based on the ALE framework, its governing equations include advective terms allowing an arbitrary description of motion. Thus, in addition of accounting for a stabilizing low-Mach scheme, a PST is implemented through the arbitrary transport velocity field, the asset of ALE formulations. Through a nonlinear stability analysis, CFL-like conditions are formulated ensuring the scheme conservativity, robustness, stability and consistency. Besides, stability intervals are defined for the scheme parameters determining entirely the stability field. Its implementation on several test cases reveals particularly that the proposed scheme faithfully reproduces the strain localization in adiabatic shear bands, a precursor to failure. By preventing spurious oscillations in elastic waves and correcting the so-called tensile instability, it increases both stability and accuracy with respect to classical approaches.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78222654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coils, Codes and Comets: My Attempts to Partially Understand Some Particular Aspects of Hypervelocity Impacts","authors":"D. Crawford","doi":"10.1115/hvis2019-dsa2017","DOIUrl":"https://doi.org/10.1115/hvis2019-dsa2017","url":null,"abstract":"\u0000 At the time of this writing in 2019, I have been studying hypervelocity impacts for about 34 years. I attended my first Hypervelocity Impact Symposium in 1992. In this paper, I attempt to show what I’ve been up to all this time but also show some of the things I’ve learned along the way. I’ve singled out three topics that stand out in my mind as milestones in my career: the impact of Comet Shoemaker-Levy 9 on Jupiter in 1994, the development of adaptive mesh refinement for the CTH hydrocode in 1998-2001 and my ongoing studies of hypervelocity impact-generated magnetic fields from 1985 to the present day.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"116 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79301291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}