Penetration of a Shaped Charge

Total Page:16

File Type:pdf, Size:1020Kb

Penetration of a Shaped Charge Penetration of a Shaped Charge Chris Poole Corpus Christi College University of Oxford A thesis submitted for the degree of Doctor of Philosophy Trinity 2005 Acknowledgements This research was funded by the EPSRC and QinetiQ, both of whom I would like to thank for funding the project. I would also like to thank my supervisor, Jon Chapman, for his inspiration and guidance throughout this work. I am also indebted to John Curtis (QinetiQ) for his invaluable support on the project. I must also thank John Ockendon, who has been a fountain of enthusiasm and stimulation throughout the project. Sasha Korobkin must be thanked for his input and insight into the chapter on filling-flows. The metallurgical analysis would not have been possible without the help of Paula Topping and others in the Materials Department, whom I would like to acknowledge. Finally, on a Mathematical note, I would like to thank all those in OCIAM who have helped me throughout the project. On a more personal level, I would like to thank all of those who have supported me and given me encouragement (and distractions!) since I have been in Oxford. In particular, I must mention the support of my family, the joviality of my friends in OCIAM (especially the DH9/DH10 folk, past and present), the conviviality of the OUSCR (and other ringers), and any other friends I haven’t yet mentioned. It is the mixture of all these people that has kept me (relatively) sane and made my time in Oxford so enjoyable. Abstract A shaped charge is an explosive device used to penetrate thick targets using a high velocity jet. A typical shaped charge contains explosive material behind a conical hollow. The hollow is lined with a compliant material, such as copper. Extremely high stresses caused by the detonation of the explosive have a focusing effect on the liner, turning it into a long, slender, stretching jet with a tip speed of up to 12km s−1. A mathematical model for the penetration of this jet into a solid target is developed with the goal of accurately predicting the resulting crater depth and diameter. The model initially couples fluid dynamics in the jet with elastic- plastic solid mechanics in the target. Far away from the tip, the high aspect ratio is exploited to reduce the dimensionality of the problem by using slender body theory. In doing so, a novel system of partial differential equations for the free-boundaries between fluid, plastic and elastic regions and for the velocity potential of the jet is obtained. In order to gain intuition, the paradigm expansion-contraction of a circular cavity under applied pressure is considered. This yields the interesting possi- bility of residual stresses and displacements. Using these ideas, a more realistic penetration model is developed. Plastic flow of the target near the tip of the jet is considered, using a squeeze-film analogy. Models for the flow of the jet in the tip are then proposed, based on simple geometric arguments in the slender region. One particular scaling in the tip leads to the consideration of a two-dimensional paradigm model of a “filling-flow” impacting on an obstacle, such as a membrane or beam. Finally, metallurgical analysis and hydrocode runs are presented. Unresolved issues are discussed and suggestions for further work are presented. Contents 1 Introduction 1 1.1 What is a shaped charge? . 1 1.1.1 Mechanics of a shaped-charge jet . 1 1.1.2 Applications of shaped charges . 4 1.2 Background mathematics . 5 1.2.1 Elasticity . 5 1.2.2 Metal plasticity . 11 1.2.3 Asymptotics . 16 1.2.4 Slender body theory . 17 1.3 Thesis outline . 19 1.4 Statement of originality . 20 2 Shaped-charge literature 22 2.1 Hydrodynamic models . 22 2.1.1 Birkhoff jet impact . 22 2.1.2 Water jets . 25 2.2 Models from solid mechanics . 27 2.2.1 Models of penetration . 27 2.2.2 Plastic instability and jet particulation . 29 2.2.3 Numerical models . 30 2.3 Aims of thesis . 31 3 An axisymmetric elastic-plastic model for penetration 32 3.1 Philosophy of the model . 32 3.1.1 Parameter estimates . 34 3.2 The jet . 34 3.2.1 Boundary conditions . 36 3.3 Plastic region . 36 3.3.1 Boundary conditions . 38 i 3.4 Elastic region . 39 3.4.1 Boundary conditions . 40 3.5 Different scalings . 40 3.5.1 Geometric and other scaling ideas . 41 4 Slender and outer analysis 44 4.1 Asymptotic analysis of nondimensional slender equations . 44 4.1.1 Jet region . 45 4.1.2 Plastic region . 48 4.1.3 Inner elastic region . 54 4.2 Outer region . 56 4.2.1 Quasistatic outer region . 56 4.2.2 Matching with a fully inertial outer region . 62 4.2.3 Comments . 65 4.3 Travelling-wave solution . 65 4.4 Inertial effects . 70 4.4.1 Modified inertial equations . 70 4.5 Comments on elastic-plastic modelling . 72 5 Gun-barrel mechanics 75 5.1 Linear elastic perfect-plastic cavity model . 76 5.1.1 Elastic expansion . 76 5.1.2 Elastic-plastic expansion . 76 5.1.3 Simple plastic contraction with no residual stress . 80 5.1.4 A possible model for cavity-contraction permitting a residual stress 80 5.1.5 “Elastic contraction” . 83 5.1.6 Elastic-plastic contraction . 85 5.1.7 Cyclic loading-unloading . 89 5.2 A nonlinear problem . 93 5.2.1 Elastic expansion . 95 5.2.2 Elastic-plastic expansion . 95 5.2.3 Contraction with no re-yielding . 97 5.2.4 Contraction with further plastic flow . 98 5.2.5 Comment . 98 5.3 Application to shaped-charge penetration . 99 5.3.1 Remarks . 100 5.4 An asymmetric perturbation to the gun-barrel problem . 101 5.4.1 Perturbation εY (θ, t) = ε(1 + cos θ)Q(t) to the cavity pressure . 103 5.4.2 Perturbation εY (θ, t) = ε(1 + cos Nθ)Q(t), N ≥ 2 to the cavity pressure . 107 5.4.3 Remarks . 110 5.4.4 Effects of applying a non-radially-symmetric perturbation with vary- ing sign as a function of θ to a plasticised annulus . 111 5.4.5 Remarks . 112 6 Ideas for a full elastic-plastic model 114 6.1 A full elastic-plastic model for the tip . 114 6.1.1 Tip jet region . 115 6.1.2 Plastic region . 116 6.1.3 Elastic region . 117 6.1.4 ‘Plasticised’ elastic region . 117 6.1.5 Remarks . 118 6.2 Squeeze film analogy . 120 6.2.1 Viscous squeeze film . 120 6.2.2 Elasto-plastic squeeze film under horizontal tension . 122 6.2.3 Elastic-plastic squeeze film under horizontal compression . 129 6.2.4 Elasto-plastic squeeze film under compression, with known, varying base . 130 6.2.5 Remarks . 133 7 Paradigm tip models for the jet 135 7.1 Simple two-dimensional filling-flow models for the jet . 136 7.1.1 A filling flow in a channel with constant height with various end- conditions . 137 7.1.2 Comments . 153 7.2 A model for a filling flow impacting a pre-stressed membrane . 154 7.2.1 Inner and outer analysis . 156 7.2.2 Global travelling wave solution . 163 7.3 A model for a filling flow impacting a pre-stressed beam . 168 7.3.1 Inner and outer analysis . 169 7.3.2 Global travelling wave solution . 171 7.4 A filling-flow impact model with general constitutive law p = p(H).... 173 7.4.1 Similarity solution . 175 7.5 Axisymmetric filling flows . 177 7.5.1 General constitutive law p = p(R).................. 180 7.5.2 Similarity solution . 181 7.6 Remarks . 182 8 Metallurgical and hydrocode analysis 184 8.1 Shaped charge metallurgy literature . 184 8.2 Metallurgical analysis . 185 8.2.1 Microscopic analysis . 189 8.3 Pictures of the microstructure . 190 8.3.1 Images from ‘Face 1’ . 190 8.3.2 Images from ‘Face 2’, with penetration occurring ‘into’ the paper . 197 8.3.3 Observations . 199 8.3.4 Remarks . 201 8.4 Hardness . 201 8.4.1 Hardness testing of the steel specimen . 203 8.4.2 Remarks on hardness test results . ..
Recommended publications
  • Comparison of Dynamic Tensile Extrusion Behaviour of Wcu Composites Made by Different Processes
    EPJ Web of Conferences 183, 03004 (2018) https://doi.org/10.1051/epjconf/201818303004 DYMAT 2018 Comparison of dynamic tensile extrusion behaviour of WCu composites made by different processes Leeju Park1,2,*,Sanghyun Woo1,2, Yerim Lee1 , Keunho Lee1 , and Young Sun Yi 1 1The 4th Research and Development Institute, Agency for Defence Development, 34186 Daejeon, Republic of Korea 2Weapon Systems Engineering, Korea University of Science and Technology, 34113 Daejeon, Republic of Korea Abstract. Composites with 60~90% of tungsten are used in liners of some specialty shaped charges. The penetration is enhanced by a factor against copper for homogeneous steel target. Tungsten powder based shaped charge liners are also especially suitable for oil well completion. In this study, WCu composites manufactured by different process are used for testing of dynamic tensile extrusion (DTE) behaviour. One samples were made by copper infiltrated method. The other samples were manufactured by metal injection molding methods with reduced tungsten copper composite powder. DTE tests were carried out by launching the sphere samples (Dia. 7.62mm) to the conical extrusion die at a speed of ~375m/s. The DTE fragmentation behaviour of tungsten copper composites after soft-recovered were examined and compared with each other. 1 Introduction to each other through DTE test. Tungsten–copper (WCu) is a mixture of tungsten and copper. As tungsten and copper are not mutually soluble, 2 Experimental the material is composed of distinct particles of copper There are many methods making tungsten copper dispersed in a matrix of tungsten. So, we are called a tungsten copper composite instead of a tungsten copper composite.
    [Show full text]
  • MAGTF Antiarmor Operations
    MCWP 3-15.5 (CD) MAGTF Antiarmor Operations Chapter 3 MAGTF Antiarmor Weapons and Techniques The MAGTF possesses a vast array of weapons systems with anti armor capabilities. While later chapters will address the proper integration of these weapons systems in a combined arms role, it is imperative that the reader understand the capabilities and limitations of each weapon system against a tank or other types of armored vehicles. Since improvement of weapon capabilities and armor is ongoing and information is often classified, the reader should consult the unit S-2 for timely updates on this subject matter. Section I. Antiarmor Weapons Systems 3101. Weapons Systems The M1A1 main battle tank is powered by a gas turbine engine rated at 1,500 hp, with a 23.8 hp/ton ratio. This MBT has a maximum speed of 42 mi/h and a cruising range of 275 miles. The MlA1 has a laser range finder, optical day sight, and a thermal imaging night sight. With the fording kit, it is capable of moving in water at turret roof depth. The M1A1 fires only Sabot (kinetic energy round) and the high explosive antitank (HEAT) (high explosive [HE] shaped charge), and the Mult-purpose Anti-Tank (MPAT) which is an air/ground fused version of the HEAT round. Crew 4 Weight 67.59 tons Armament 120mm smoothbore tank gun MER for HEAT, APFSDS, and MPAT range 4000m .50 cal M2 MG tank commanders Maximum effective range 1830 m 7.62 mm Coax MG and 7.62 mm Coax MG Maximum effective range 900 m Basic Load 44 rounds main gun Figure 3-1.
    [Show full text]
  • Shaped Charges Having a Porous Tungsten Liner-An Experimental and Theoretical Study of Metal Compression, Jet Formation and Penetration Mechanics
    New Jersey Institute of Technology Digital Commons @ NJIT Dissertations Electronic Theses and Dissertations Fall 1-31-1997 Shaped charges having a porous tungsten liner-an experimental and theoretical study of metal compression, jet formation and penetration mechanics Brian Edward Fuchs New Jersey Institute of Technology Follow this and additional works at: https://digitalcommons.njit.edu/dissertations Part of the Mechanical Engineering Commons Recommended Citation Fuchs, Brian Edward, "Shaped charges having a porous tungsten liner-an experimental and theoretical study of metal compression, jet formation and penetration mechanics" (1997). Dissertations. 1055. https://digitalcommons.njit.edu/dissertations/1055 This Dissertation is brought to you for free and open access by the Electronic Theses and Dissertations at Digital Commons @ NJIT. It has been accepted for inclusion in Dissertations by an authorized administrator of Digital Commons @ NJIT. For more information, please contact [email protected]. Copyright Warning & Restrictions The copyright law of the United States (Title 17, United States Code) governs the making of photocopies or other reproductions of copyrighted material. Under certain conditions specified in the law, libraries and archives are authorized to furnish a photocopy or other reproduction. One of these specified conditions is that the photocopy or reproduction is not to be “used for any purpose other than private study, scholarship, or research.” If a, user makes a request for, or later uses, a photocopy or reproduction for purposes in excess of “fair use” that user may be liable for copyright infringement, This institution reserves the right to refuse to accept a copying order if, in its judgment, fulfillment of the order would involve violation of copyright law.
    [Show full text]
  • Improvement of Penetration Performance of Linear Shaped Charges
    Projectile Impacts: modelling techniques and target performance assessment 87 Improvement of penetration performance of linear shaped charges H. Miyoshi1, H. Ohba2, H. Kitamura2, T. Inoue2 & T. Hiroe3 1Project Division, Chugoku Kayaku Co., Ltd., Japan 2Yoshii Plant, Chugoku Kayaku Co., Ltd., Japan 3Department of Mechanical Engineering and Materials Science, Kumamoto University, Japan Abstract Experiments with and simulations of linear shaped charges (LSCs) have been conducted to improve the penetration performance and minimize collateral damage by fragments. Annealed tough pitch copper was selected for an appropriate liner material. The penetration depth increased by 50%, compared to current LSCs. The detonation effects of the explosive change the liner into jet and slug. However, the case is also transformed into fragments, which creates undesirable collateral damage. Polyvinyl chloride was adopted as the case material to reduce damage by fragments. No fragments were generated when the newly-designed LSCs were shot. For the simulation of the jet formation and target penetration, the AUTODYN planar Euler solver was selected, and the liner, case and explosive were filled on the Euler solver plane. The calculation results provided significant information about determining the optimal stand-off distance and allow the design of effective cutting plans for use with LSCs. Keywords: linear shaped charges, target penetration, stand-off distance, Euler solver. 1 Introduction Liner shaped charges (LSCs) have the ability of instantaneous cutting of structures and have been used in the separation of the first and second stages, and the command destruction of solid rocket boosters (SRB) in the H-2A rocket. In the military field, LSCs are used for the separation of the capsule in the anti- WIT Transactions on State of the Art in Science and Engineering, Vol 75, © 2014 WIT Press www.witpress.com, ISSN 1755-8336 (on-line) doi:10.2495/978-1-84564-879-4/009 88 Projectile Impacts: modelling techniques and target performance assessment submarine rockets.
    [Show full text]
  • Damage Mechanism of PTFE/Al Reactive Charge Liner Structural Parameters on a Steel Target
    materials Article Damage Mechanism of PTFE/Al Reactive Charge Liner Structural Parameters on a Steel Target Xuepeng Zhang 1,*, Zhijun Wang 1, Jianping Yin 1, Jianya Yi 1 and Haifu Wang 2,* 1 School of Mechatronic Engineering, North University of China, Taiyuan 030051, China; [email protected] (Z.W.); [email protected] (J.Y.); [email protected] (J.Y.) 2 State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China * Correspondence: [email protected] (X.Z.); [email protected] (H.W.); Tel.: +86-010-68918584 (H.W.) Abstract: The incorporation of reactive material damage element technology in ammunition war- heads is a research hotspot in the development of conventional ammunition. The research results are of great significance and military application value to promote the development of high-efficiency damage ammunition technology. In this paper, we aimed to understand the behavior of the reactive jet and its damage effect on a steel target by undertaking theoretical analysis, numerical simulation, and experimental research. We studied the influence of structural and material parameters on the shape of the reactive jet based on autodyn-2d finite element simulation software, and the formation behavior of the reactive jet was verified using a pulsed X-ray experiment. By studying the combined damage caused by the steel target penetrating and exploding the reactive jet, the influence of the structural and performance parameters, and the explosion height of the reactive jet liner on the damage effect to the steel target was studied. A static explosion experiment was carried out, and the optimal structural and performance parameters for the reactive material and explosion height of the Citation: Zhang, X.; Wang, Z.; Yin, J.; reactive jet liner were obtained.
    [Show full text]
  • Penetration in Granite by Shaped Charge Liners of Various Metals
    Scholars' Mine Doctoral Dissertations Student Theses and Dissertations 1970 Penetration in granite by shaped charge liners of various metals Hemendra Nath Kalia Follow this and additional works at: https://scholarsmine.mst.edu/doctoral_dissertations Part of the Mining Engineering Commons Department: Mining Engineering Recommended Citation Kalia, Hemendra Nath, "Penetration in granite by shaped charge liners of various metals" (1970). Doctoral Dissertations. 2038. https://scholarsmine.mst.edu/doctoral_dissertations/2038 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. PENETRATION IN GRANITE BY SHAPED CHARGE LINERS OF VARIOUS METALS by HEMENDRA NATH KALlA, 1939 A DISSERTATION Presented to the Faculty of the Graduate School of the UNIVERSITY OF MISSOURI-ROLLA In Partial Fulfillment of the Require~ts for the Degree DOCTOR OF PHILOSOPHY in MINING ENGINEERING T2388 1970 c. I 92 pages 193955 i i ABSTRACT The penetration in Missouri red granite by cylindrical charges with metal liners of aluminum 2011 (T-3), aluminum 7075 (T-6), yellow brass, monel, maraging steel (vascomax 250), and copper was measured. Metals having high ductility and moderate compressive strength penetrated deeper than high strength maraging steel. Aluminum required a greater standoff for optimum penetration than the other metal liners tested. Preliminary metallographic studies of the liner metals and slugs showed that the grains had elongated along the slug axis. The metals containing zinc formed very small or no slugs.
    [Show full text]
  • Material Combination to Mitigation of Behind Armour Debris After Shaped
    MATEC Web of Conferences 182, 02009 (2018) https://doi.org/10.1051/matecconf/201818202009 17th International Conference Diagnostics of Machines and Vehicles Material combination to mitigation of behind armour debris after shaped charge jet attack Marek Szudrowicz1,*1 1Wojskowy Instytut Techniki Pancernej i Samochodowej, 05-070 Sulejówek, Okuniewska 1, Poland Abstract. When a shaped charge jet perforates the steel armour plate, the residual jet is accompanied by a much wider cloud of behind armour debris (BAD) generated by stress wave interactions. BAD plays an important role in the evaluation of survivability of vehicle crew and components in a vehicle. The Behind Armor Debris (BAD) cloud caused by shaped charge jet impact was investigated. In order to simulate different configuration of material to mitigation of debris cloud the thickness of ceramics target tiles, glass and aramid laminate liners in contact with the armour plates was varied. 1 Introduction Armour Piercing Discarding Sabot (APDS) projectiles and High Explosive Anti-Tank (HEAT) warheads are the main weapons used to damage or destroy armoured vehicles. If a such a warhead hits a vehicle, the highest danger for the crew is posed, apart primary jet, by fragments of the primary jet and armour spalls, which may reach a speed o 1000 m/s in case of heavier fragments and about 3000 m/s in case of the lighter ones. Additionally, effects related to changes of temperature and pressure should be considered (Fig. 1) [1]. Fig. 1. Effects of the penetration of armour. Behind armour debris. The following means are employed in design solutions in order to increase the chances of a vehicle crew to survive when vehicle is in danger of being hit by a HEAT warhead: - detonation of the warhead or otherwise destroying it at some distance from the vehicle, - disturbing, breaking or fragmenting the shaped charge jet produced after detonation of the warhead, - reduction of the depth of penetration, - minimizing of the above-mentioned detrimental effects caused by shaped charge jet penetrating the armour [2,3,4,5,6,7].
    [Show full text]
  • And Applications of Shaped Charges to Explosive Filled Ordnance
    RESTRICTED OP 1720 SHAPED CHARGE AMMUNITION AND APPLICATIONS OF SHAPED CHARGES TO EXPLOSIVE FILLED ORDNANCE A BUREAU OF ORDNANCE PUBLICATION 9 JUNE 1947 RESTRICTED OP 1720 TH£ CLASSIFICATION OF THJS P^UCAIION HAS SEEN RESRADED M^MARK THIS COPY rj accordance WITH secnav RESTRICTION 5510.10A. SHAPED CHARGE AMMUNITION AND APPLICATIONS OF SHAPED CHARGES TO EXPLOSIVE FILLED ORDNANCE 9 JUNE 1947 This publication is RESTRICTED and shall be safeguarded in accordance with the security provisions of U.S. Navy Regulations, 1920, Article 76. NAVY DEPARTMENT BUREAU OF ORDNANCE WASHINGTON 25. D. C. 9 June 1947. RESTRICTED ORDNANCE PAMPHLET 1720 SHAPED CHARGE AMMUNITION AND APPLICATIONS OF SHAPED CHARGES TO EXPLOSIVE FILLED ORDNANCE 1. Ordnance Pamphlet 1720 contains a summary of pertinent information con­ cerning all shaped charge items developed under the coordination of the Joint Army-Navy-N.D.R.C. Shaped Charge Committee and now in use by the U. S. Navy or the U. S. Army. It also contains detailed information on utilizing shaped charges for opening explosive-filled ordnance. 2. This publication supersedes OP 1203 and OP 1647, copies of which should be destroyed in accordance with security regulations. 3. This publication is RESTRICTED and shall be safeguarded in accordance with security provisions of U. S. Navy Regulations, 1920, Article 76 or U. S. Army Regulations, 380-5, 15 August 1946. G. F. Hussey, Jr., Nice Admiral, U. S. Navy, Chief of the Bureau of Ordnance. il RESTRICTED 1 CONTENTS Chapter Page 1. Introduction..................................................................................................... 1 2. Standard Ordnance Shaped Charges: Rifle Grenade, AT, M9A1 ................................................................... 4 Rocket, HE, AT, 2.36-inch, M6A5...................................................
    [Show full text]
  • Explosive Shaped Charge Penetration Into Tuff Rock
    SANDIA REPORT SAND88 - 2338 • UC - 35 Unlimited Release Printed October 1988 Explosive Shaped Charge Penetration Into Tuff Rock M. G. Vigil Prepared by Sandia Natiqnal Laboratories Ai~uquerque, New Mexico 87185 and Livermore, California 94550 for the United States Departmen~ of Energy under Contract DE-AC04-76DPOO789 When printing a copy of any digitized SAND Report, you are required to update the markings to current standards. SF2900Q(S-S1) Issued by Sandia National Laboratories, operated for the United States Department of Energy by Sandia Corporation. NOTICE: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Govern­ ment nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government, any agency thereof or any of their contractors or subcontractors. The views and opinions expressed herein do not necessarily state or reflect those of the United States Government, any agency thereof or any of their contractors or subcontractors. Printed in the United States of America Available from National Technical Information Service U.S. Department of Commerce 5285 Port Royal Road Springfield, VA 22161 NTIS price codes Printed copy: A04 Microfiche copy: AOI SAND88~2338 UC-35 Unlimited Release Printed October 1988 EXPLOSIVE SHAPED CHARGE PENETRATION INTO TUFF ROCK Manuel G.
    [Show full text]
  • Improvement of Penetration Performance of Linear Shaped Charges
    Computational Ballistics II 159 Improvement of penetration performance of linear shaped charges H. Miyoshi1, H. Ohba2, H. Kitamura2, T. Inoue2 & T. Hiroe3 1Project Division, Chugoku Kayaku Co., Ltd., Japan 2Yoshii Plant, Chugoku Kayaku Co., Ltd., Japan 3Department of Mechanical Engineering and Materials Science, Kumamoto University, Japan Abstract Experiments and simulations of linear shaped charges (LSCs) have been conducted to improve the penetration performance and minimize collateral damage by fragments. Annealed tough pitch copper was selected for an appropriate liner material. The penetration depth increased by 50 %, compared to current LSCs. The detonation effects of the explosive change the liner into the jet and slug. But, the case is also transformed into fragments, which creates undesirable collateral damage. Polyvinyl chloride was adopted as the case material to reduce damage by fragments. No fragments were generated when the newly-designed LSCs were shot. For the simulation of the jet formation and target penetration, the Euler solver of AUTODYN on the two-dimension planar was selected, and the liner, case and explosive were filled on the Euler solver plane. The calculation results gave us significant information about determining the optimal stand-off distance and allow us to design effective cutting plans for use with LSCs. Keywords: linear shaped charges, target penetration, stand-off distance, Euler solver. 1 Introduction Liner shaped charges (LSCs) have the ability for the instantaneous cutting of the structures and have been used in the separation of the first and second stages, and the command destruction of solid rocket boosters (SRB) in the H-2A rocket. In the field of the military, LSCs are used the separation of the capsule in the anti- WIT Transactions on Modelling and Simulation, Vol 40, © 2005 WIT Press www.witpress.com, ISSN 1743-355X (on-line) 160 Computational Ballistics II submarine rockets.
    [Show full text]
  • Establishment of Shaped Charge Optimum Parameters for Small Scale Hydrodynamic Penetration
    Modern Applied Science; Vol. 10, No. 1; 2016 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education Establishment of Shaped Charge Optimum Parameters for Small Scale Hydrodynamic Penetration Khairul H. Kamarudin1, Ahmad Mujahid Ahmad Zaidi1, Shohaimi Abdullah1 & Md Fuad Shah Koslan1 1 Faculty of Engineering, National Defence University of Malaysia, Malaysia Correspondence: Khairul H. Kamarudin, Faculty of Engineering, National Defence University of Malaysia, 57000 Kuala Lumpur, Malaysia. Tel: 60-13-620-4605. E-mail: [email protected] Received: September 9, 2015 Accepted: September 25, 2015 Online Published: December 22, 2015 doi:10.5539/mas.v10n1p82 URL: http://dx.doi.org/10.5539/mas.v10n1p82 Abstract An investigation is intended to establish suitable parameters for a simple shaped charge mechanism (SCM) assembly that can be utilized for small scale hydrodynamics penetration test. Some basic features of the SCM parameters were based on previous researchers’ findings. Three sets of tests were conducted to verify parameters such as cone liner angle and thickness, material of charge (explosive) casing and standoff distance (SoD). Single and welded stacks of mild steel plates and Aluminium blocks were used as targets. Two type of explosive were used, military grade plastic explosive (PE) or C4 and a commercial grade explosive, Emulex 700. A simple but effective compressing mechanism was developed to eliminate air pockets and maximised the explosive density. The SCM parameters were improved through series of tests and results have shown that hydrodynamic penetrations have taken place in every test conducted. Suitable small scale SCM parameters were successfully established which can be utilized for future study on hydrodynamics penetration.
    [Show full text]
  • Explosive Applications for Industry and Defense
    Explosive Applications for Industry and Defense Speaker: Arran Gordon Company: Havoc Industries Pty Ltd Date: 19-Oct-06 1 Types of Explosives • “Low” Explosives – Burn or deflagrate rather than detonate. Velocity of Detonation (VOD) of less than 1,000 m/s. • “High” Explosives – Detonate as a shock wave passes through the material. VOD in the range of 4,500 to 8,000 m/s • Blasting Agents – Bulk high explosives that are not detonator sensitive. • Initiating Explosives – Highly sensitive. TYPES OF EXPLOSIVES "LOW" EXPLOSIVES Burn or Deflagrate rather than Detonate Produce large volumes of gas which "explode" if confined VOD less than 1,000 m/s Examples: Black Powder – Pyrotechnics, Smokeless Powder - Propellant for Bullets / Shells "HIGH" EXPLOSIVES Detonate as Detonation Shock Wave passes through VOD greater than 1,000 m/s - typically 5,000 to 8,000 m/s Produce very high pressures, even when unconfined Examples: TNT, Dynamite, Mining Explosives - Watergels, Emulsions and Slurries, ANFO BLASTING AGENTS Are High Explosives Are less sensitive and more difficult to initiate Are not detonator or "cap" sensitive Examples: ANFO, Some Emulsions and Slurries INITIATING EXPLOSIVES High explosives that are very sensitive to heat and shock Used in small quantities in detonators Examples: Mercury Fulminate, Lead Azide, Lead Styphnate HISTORY OF EXPLOSIVES BLACK POWDER OR VARIANTS "Greek Fire" used in battle 668 AD - petroleum distillate thickened with resins Chinese references to gunpowder in 1040 AD ("Wu Ching Tsing Yao") English Friar Roger Bacon
    [Show full text]