Download or read book Statistical Analysis of the Particulation of Shaped Charge Jets written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A statistical analysis of shaped charge jet break-up was carried out in order to investigate the role of nonlinear instabilities leading to the particulation of the jet. Statistical methods generally used for studying fluctuations in nonlinear dynamical systems are applied to experimentally measured velocities of the individual particles. In particular we present results suggesting the deviation of non-Gaussian behavior for interparticle velocity correlations, characteristic of nonlinear dynamical systems. Results are presented for two silver shaped charge jets that differ primarily in their material processing. We provide evidence that the particulation of a jet is not random, but has its origin in a deterministic dynamical process involving the nonlinear coupling of two oscillators analogous to the underling dynamics observed in Rayleigh-Benard convection and modeled in the return map of Curry and Yorke.

Download or read book Fundamentals of Shaped Charges written by William P. Walters and published by Wiley-Interscience. This book was released on 1989 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to the art and science of developing shaped charges. Presents the history of shaped charges, the principles governing their design, and a variety of example applications. Includes discussion of Gurney and Taylor methods, jet formation, the visco-plastic model, jet penetration, fabrication, computational aspects, and how to design shaped charges for different applications. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book High speed High resolution Observations of Shaped charge Jets Undergoing Particulation written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Image-converter (IC) camera photography has provided spectacular images and quantitative records of liner collapse and early jet formation in shaped charges. We have extended the application of the IC camera to observations of shaped charge jet surfaces undergoing particulation. Sequential, high-resolution photographs were taken following the same 10-cm portion of jet at 2.5-[mu]s intervals. Simultaneous color rotating-mirror framing camera photographs and 450-keV flash x-ray radiographs were also taken of the same region. This combination provides a detailed record of the evolution of surface structure during jet necking and particulation. In the high-resolution photographs, individual features on the jet surfaces as small as[approximately]100[mu]m can easily be detected and followed as they evolve over time. The jet surface structure is rough with overlapping slip dislocation lines running along the surface at 45[degree] to either side of the jet axis. This is similar to the texture that develops in long rods undergoing static tension. We discuss the implications of these images for increasing jet particulation times.

Download or read book Particulation in Jets from Free form Hemispherical Shaped Charges with Copper Liners written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Jets from Explosive Shaped Charges written by R. D. Shelton and published by . This book was released on 1978 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: A shaped charge jet, approximated as a right circular cylinder with a uniform velocity gradient, is treated from the energetic and stochastic viewpoints to yield, as a function of material properties, the size distribution of jet particles after jet break-up.

Download or read book Jahresbericht der St Annen Schule Womit written by and published by . This book was released on 1897 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Velocity Difference Between Particulated Shaped Charge Jet Particles for Face Centered Cubic Liner Materials written by William P. Walters and published by . This book was released on 1992 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model was derived to predict the average jet velocity difference between particulated shaped charge jet particles. The model is based on the 'wire drawing formula presented by Kolsky, the plastic instability criterion, and the Zerilli-Armstrong constitutive equation for face-centered-cubic materials. The velocity difference expression is strongly dependent on the jet temperature and weakly dependent on the jet strain rate. Calculations were also made using the Johnson-Cook constitutive model. The average velocity difference between jet particles, the true stress at necking, and the true strain at necking were calculated using several variants of the model. Velocity difference comparisons with experimental data were made for several shaped charge designs with copper liners of various geometries. shaped charges; jet characteristics; jet breakup time; velocity difference; jet particles; strain rate effects; strain rate.

Download or read book Penetration of Shaped charge Jets Into Glass and Crystalline Quartz written by and published by . This book was released on 1991 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Particulation of Shaped Charge Jets written by Manfred Held and published by . This book was released on 1989* with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A New 3D Computational Model for Shaped Charge Jet Breakup written by and published by . This book was released on 1996 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper reviews prior 1D and 2D axisymmetric, analytical and computational studies, as well as empirical studies of the shaped charge jet particulation problem and discusses their associated insights and problems. It proposes a new 3D computational model of the particulation process, based upon a simplified version of the observed counter-rotating, double helical surface perturbations, found on softly recovered shaped charge jet particles, from both copper and tantalum jets. This 3D approach contrasts with the random, axisymmetric surface perturbations which have previously been used, to try to infer the observed length distribution of jet particles, on the basis of the most unstable wavelength concept, which leads to the expectation of a continuous distribution of particle lengths. The 3D model, by its very nature, leads to a non-random, periodic distribution of potential initial necking loci, on alternate sides of the stretching jet. This in turn infers a potentially periodic, overlapping, multi-modal distribution of associated jet particle lengths. Since it is unlikely that all potential initial necking sites will be activated simultaneously, the 3D model also suggests that longer jet particles containing partial, but unseparated necks, should be observed fairly often. The computational analysis is in its very early stages and the problems involved in inserting the two helical grooves and in defining the initial conditions and boundary conditions for the computation will be discussed. Available initial results from the 3D computation will be discussed and interpreted.

Download or read book The Generation and Penetration Characteristics of High Density Shaped Charge Jets written by Joseph M. Regan and published by . This book was released on 1965 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: A high density jet was successfully generated. The penetration characteristics of the jet into steel are analyzed. (Author).

Download or read book The Particulation of a Shaped Charge Jet for Face Centered Cubic Liner Materials written by William P. Walters and published by . This book was released on 1993 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical model was derived to predict the breakup time distribution and the strain at breakup of the jet from a shaped charge liner. The model invoked a plastic stability criterion, kinematic considerations, and the Zerilli-Armstrong constitutive model for face-centered-cubic liner materials. The model revealed excellent agreement with experimental data for several liner geometries but is strongly dependent on the jet temperature distribution as well as the initial strain rate ... Strain rate, Kinematics, Velocity, Cumulative breakup time, Particulation.

Download or read book Penetration Cutoff Velocities of Shaped Charge Jets written by Manfred Held and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A STUDY OF THE BREAK UP OF SHAPED CHARGE JETS written by and published by . This book was released on 1963 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several possible explanations of the mechanism of the break-up of shaped charge jets are suggested. An approach using the assumption of visco-plastic flow is presented in detail. According to this approach, a constant area jet with linear velocity gradient breaks first at the tip, and then the break-up progresses back towards the rear. The average length of the fragments could be adjusted to two per cent of the original jet length if a coefficient of viscosity of 100 lb.-sec./sq. ft. were used.

Download or read book Calculation of Shaped Charge Jets Using Engineering Approximations and Finite Difference Computer Codes Volume I Generalized Analytical Approach to Shaped Charge Warhead Design written by and published by . This book was released on 1973 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes a technique to optimize the current shaped charge design procedure as follows. Starting with the desired target to be defeated, a determination of the desired penetration characteristics of the jet would be made. Existing jet penetration theory would then be used to estimate the ideal characteristics of the jet to defeat the given target. A shaped charge launcher would then be designed to give these ideal jet characteristics. However, a suitable design procedure requires: (1) a viable analytical or empirical design approach to obtain a first cut shaped charge design, (2) a better understanding than now exists of the detailed mechanisms of jet formation, and (3) a better understanding of the phenomenon of jet penetration. This report, which is contained in two volumes, addresses the first two of these requirements. Volume I describes the use of the existing non-steady state theory of jet formation with experimental data and one-dimensional finite difference continue mechanics calculations to obtain the liner collapse velocity for generalized axisymmetric shaped charges. The results of this work are then used to obtain nonunique shaped charge designs which give the required idealized jet parameters.

Download or read book Analysis of the Shaped Charge Jet Induced Reaction of High Explosives written by Manfred Held and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of soft Recovered Shaped Charge Jet Particles written by and published by . This book was released on 1996 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: A shaped charge with an 81 mm diameter, 42° apex angle oxygen-free high-conductivity (OFHC) copper conical liner was fired into a ''soft'' recovery bunker to allow metallurgical examination of recovered jet particles and the slug. The initial weight of the copper liner was 245 g, of which 184 g was recovered. The number of jet particles recovered was 37 (approximately 63% of the particles formed by the charge). Extensive metallurgical analyses were performed on the recovered slug and jet particles. The microstructural features associated with voids, e.g., dendritic grain growth, clearly indicate that the regions in the vicinity of the centerline of the slug and jet particles were melted. In this work the authors present calculations of jet temperature as a function of constitutive behavior. In order to predict melt in the center region of the jet they find it necessary to scale flow stress with a pressure dependent shear modulus.