Fragmentation of Rings and Shells

Fragmentation of Rings and Shells
Author: Dennis Grady
Publisher: Springer Science & Business Media
Total Pages: 375
Release: 2007-07-13
Genre: Technology & Engineering
ISBN: 3540271457

For a brief period during the latter part of World War II, Nevill F. Mott led a theoretical group at Fort Halstead in the United Kingdom that tackled scientific issues related to pressing war-time concerns. Among later awards and honors, Mott was knighted and a recipient of the Nobel Prize. While at Fort Halstead, he undertook an effort to theoretically describe the statistical fragmentation of munitions subjected to intense explosive loading. Mott`s original internal reports contain seminal theoretical concepts on the physics and statistics of dynamic fracture and fragmentation, which have provided the inspiration for numerous later modeling efforts and engineering formulae. Some of his most forward-looking thoughts on the micromechanical and molecular aspects of fracture are included in these publications. The present book surveys the theoretical analysis put forth by Mott with particular focus on his efforts to characterize the size and distribution of fragments resulting from a dynamic fragmentation event. Copies of the original internal reports of Mott and his co-workers are included. The book also pursues additional theoretical analysis with the intent of delving further into the physical ideas and unfinished analysis implicit in Mott`s original studies. This book will be of interest to all scientists and engineers concerned with the dynamic fracture and fragmentation of solid bodies subject to intense transient loads imparted by explosive detonation and high-velocity impact from both the historical and modern perspective.

Cylinder Expansion (Gurney Constant) and Warhead Fragmentation. Part 2. Computerized Data Reduction

Cylinder Expansion (Gurney Constant) and Warhead Fragmentation. Part 2. Computerized Data Reduction
Author:
Publisher:
Total Pages: 78
Release: 1972
Genre:
ISBN:

Development of a cylinder expansion test for use in assessing the metal acceleration capability of explosives is discussed. A precisely manufactured metal cylinder is filled with explosive, and its wall expansion during detonation is observed with a streak camera. The photographic record of the cylinder expansion is analyzed by mechanized film reading and high speed computer techniques. The maximum velocity attained by the wall fragments is taken as a measure of the momentum imparted to the metal by the explosive. Both manual and automated methods of data reduction for attainment of test results are given. When standardized, this test procedure will permit the correlation of the evaluations of explosive compounds between laboratories. The computerized reduction of the pictorial data to tabular listings and graphic displays is also discussed.

Dynamic Damage and Fragmentation

Dynamic Damage and Fragmentation
Author: David Edward Lambert
Publisher: John Wiley & Sons
Total Pages: 439
Release: 2019-01-14
Genre: Technology & Engineering
ISBN: 1119579341

Engineering structures may be subjected to extreme high-rate loading conditions, like those associated with natural disasters (earthquakes, tsunamis, rock falls, etc.) or those of anthropic origin (impacts, fluid–structure interactions, shock wave transmissions, etc.). Characterization and modeling of the mechanical behavior of materials under these environments is important in predicting the response of structures and improving designs. This book gathers contributions by eminent researchers in academia and government research laboratories on the latest advances in the understanding of the dynamic process of damage, cracking and fragmentation. It allows the reader to develop an understanding of the key features of the dynamic mechanical behavior of brittle (e.g. granular and cementitious), heterogeneous (e.g. energetic) and ductile (e.g. metallic) materials.

Habitat Fragmentation and Landscape Change

Habitat Fragmentation and Landscape Change
Author: David B. Lindenmayer
Publisher: Island Press
Total Pages: 349
Release: 2013-02-22
Genre: Nature
ISBN: 159726606X

Habitat loss and degradation that comes as a result of human activity is the single biggest threat to biodiversity in the world today. Habitat Fragmentation and Landscape Change is a groundbreaking work that brings together a wealth of information from a wide range of sources to define the ecological problems caused by landscape change and to highlight the relationships among landscape change, habitat fragmentation, and biodiversity conservation. The book: synthesizes a large body of information from the scientific literature considers key theoretical principles for examining and predicting effects examines the range of effects that can arise explores ways of mitigating impacts reviews approaches to studying the problem discusses knowledge gaps and future areas for research and management Habitat Fragmentation and Landscape Change offers a unique mix of theoretical and practical information, outlining general principles and approaches and illustrating those principles with case studies from around the world. It represents a definitive overview and synthesis on the full range of topics that fall under the widely used but often vaguely defined term "habitat fragmentation."

Governance Fragmentation and Urban Spatial Expansion

Governance Fragmentation and Urban Spatial Expansion
Author: Silvia Beghelli
Publisher:
Total Pages:
Release: 2019
Genre:
ISBN:

This study assesses the effects of urban governance structure on the spatial expansion of metropolitan areas. A more fragmented governance structure, represented by a high number of administrative units with decision power on land use per inhabitant, is expected to increase the competition between small towns in the suburbs of metropolitan areas to attract households and workers, which, in turn, induces more land uptake. We study empirically the relationship between administrative fragmentation and the spatial size of cities in a sample of 180 metropolitan areas in the contexts of the US and Europe in the period 2000-2012. Results shed light on the structural differences between the two broad regions and suggest that administrative fragmentation impacts positively on land uptake in both the United States and Europe, although to different extents.

High-Pressure Shock Compression of Solids II

High-Pressure Shock Compression of Solids II
Author: Lee Davison
Publisher: Springer Science & Business Media
Total Pages: 496
Release: 2012-12-06
Genre: Science
ISBN: 1461223202

This volume concerns the fracture and fragmentation of solid materials that occurs when they are subjected to extremes of stress applied at the highest possible rates. The plan for the volume is to address experimental, theoretical, and com putational aspects of high-rate dynamic fracture and fragmentation, with emphasis on recent work. We begin with several chapters in which the emphasis falls on experimental methods and observations. These chapters address both macroscopic responses and the microscopic cause of these re sponses. This is followed by several chapters emphasizing modeling-the physical explanation and mathematical representation of the observations. Some of the models are deterministic, while others focus on the stochastic aspects of the observations. Often, the ov\!rall objective of investigation of dynamic fracture and fragmentation phenomena is provision of a means for predicting the entire course of an event that begins with a stimulus such as an impact and proceeds through a complicated deformation and fracture pro cess that results in disintegration of the body and formation of a rapidly expanding cloud of debris fragments. Analysis of this event usually involves development of a continuum theory and computer code that captures the experimental observations by incorporating models of the important pheno mena into a comprehensive description of the deformation and fracture pro cess. It is to this task that the work of the last few chapters is devoted.

Modelling of Fluid Fragmentation by Molecular Dynamics

Modelling of Fluid Fragmentation by Molecular Dynamics
Author: Igor Stepanov
Publisher: LAP Lambert Academic Publishing
Total Pages: 252
Release: 2013
Genre:
ISBN: 9783659438035

Fragmentation is an example of material failure. This is a problem with widespread applications. The fragmentation of liquids is a subset of this field but nevertheless has many applications and yet is scientifically challenging to study. A complete mathematical and physical understanding of fragmentation is currently beyond reach given the complexity involved. The aim of theory is to predict the number of fragments, their size and mass distribution and shape, as well as their velocity and spatial distributions. In the present work, numerous molecular dynamics simulations of fragmentation of expanding Lennard-Jones fluids have been performed. Two types of expansion were considered: that of Holian and Grady, and that of Blink and Hoover. Much larger systems were investigated in comparison with the previous authors (up to 0.54 million particles) and much more initial conditions. The previous authors studied systems with less than 15 000 particles. Statistical and thermal properties of fragments were investigated. The results are compared with simple fragmentation models. This book should be useful for scientists who work in fragmentation phenomena.