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The Atomic Weapons Establishment is responsible for the design, manufacture and support of warheads for the United Kingdom's nuclear deterrent. AWE plc is responsible for the day-to-day operations of AWE. AWE plc is owned by a consortium of Jacobs Engineering Group, Lockheed Martin UK, and Serco through AWE Management Ltd who hold a 25‑year contract to operate AWE. All AWE sites remain owned by the UK government who also hold a golden share in AWE plc. The company is based close to Aldermaston , with major facilities at Burghfield.The Atomic Weapons Establishment is the successor of the Atomic Weapons Research Establishment , which was built on the site of a former airfield, RAF Aldermaston. Other Atomic Weapons Establishment sites could be found at ROF Burghfield, Burghfield and ROF Cardiff, Llanishen, Cardiff, the former Royal Ordnance Factories; Orford Ness and Foulness Island. The ROF Cardiff, Orford Ness and Foulness Island sites are now closed.The establishment is the final destination for the Campaign for Nuclear Disarmament's annual march from Trafalgar Square, London. The first Aldermaston March was conceived by the Direct Action Committee and took place in 1958. There is currently a monthly women's peace camp held outside the Establishment to protest against its existence.AWE has become the target of a campaign, Action AWE of protest specifically aimed curtailing its production at the next UK elections. Wikipedia.

Barlow A.J.,Atomic Weapons Establishment
Computers and Fluids | Year: 2013

A first order cell centred Lagrangian Godunov scheme based upon the use of a dual grid to determine vertex velocities was presented by the author in [A.J. Barlow, P.L. Roe, A cell centred Lagrangian Godunov scheme for shock hydrodynamics, Comput. Fluids, 46 (2011) 133-136]. A second order version of the scheme is presented and results obtained with the new scheme are compared against those obtained with a staggered grid compatible finite element scheme [A.J. Barlow, A compatible finite element multi-material ALE hydrodynamics algorithm, Int. J. Numer. Methods Fluids 56 (2008) 953-964]. The new scheme is shown to provide comparable shock capturing to the staggered grid method while retaining the benefits of reduced mesh imprinting, robustness and improved symmetry preservation observed for the first order cell centred scheme [A.J. Barlow, P.L. Roe, A cell centred Lagrangian Godunov scheme for shock hydrodynamics, Comput. Fluids, 46 (2011) 133-136]. Two different approaches are also considered for moving the vertices using the dual grid approach, a method which reconstructs nodal velocities at the start of every timestep and a second that carries the nodal velocities as an additional variable. © 2013 Elsevier Ltd.

Youngs D.L.,Atomic Weapons Establishment
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2013

Previous research on self-similar mixing caused by Rayleigh-Taylor (RT) instability is summarized and a recent series of high resolution large eddy simulations is described. Mesh sizes of approximately 2000 × 1000 × 1000 are used to investigate the properties of high Reynolds number self-similar RT mixing at a range of density ratios from 1.5: 1 to 20: 1. In some cases, mixing evolves from 'small random perturbations'. In other cases, random long wavelength perturbations (k-3 spectrum) are added to give self-similar mixing at an enhanced rate, more typical of that observed in experiments. The properties of the turbulent mixing zone (volume fraction distributions, turbulence kinetic energy, molecular mixing parameter, etc.) are related to the RT growth rate parameter, α. Comparisons are made with experimental data on the internal structure and the asymmetry of the mixing zone (spike distance/bubble distance). The main purpose of this series of simulations is to provide data for calibration of engineering models (e.g. Reynolds-averaged Navier-Stokes models). It is argued that the influence of initial conditions is likely to be significant in most applications and the implications of this for engineering modelling are discussed. © 2013 The Author(s) Published by the Royal Society. All rights reserved.

Bourne N.K.,Atomic Weapons Establishment
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2011

An understanding of the behavior of materials in mechanical extremes has become a pressing need in order to exploit new environments. Any impulse consists of a cascade of deformation mechanisms starting with ultrafast and concluding with slower ones, yet these have not been suitably defined over the past years. This requirement has prompted the design of new experimental platforms and diagnostics and an increase in modern computer power. However, this effort has removed necessary focus on the operating suite of deformation mechanisms activated in loaded materials. This article reviews the material response and attempts to order physical pathways according to the length and time scales they operate within. A dimensionless constant is introduced to scale the contributions of component pathways by quantifying their completion with respect to the loading impulse applied. This concept is extended to suggest a new framework to describe the response to arbitrary insult and to show the relevance of particular techniques to component parts of the problem. The application of a step impulse via shock loading is shown to be the primary derivation experiment to address these needs and map components of the response. © 2011 The Minerals, Metals & Materials Society and ASM International.

A model for the initiation of hydride sites on uranium metal is described for conditions of constant hydrogen pressure. The model considers variations in hydrogen permeation through the surface oxide film due to intrinsic variations in the oxide thickness. It is proposed that thin areas of surface oxide favour enhanced hydrogen permeation through the oxide and lead to the more rapid initiation of hydride sites. The time and spatial dependence of the hydrogen concentration field in the metal underlying thin areas of oxide is calculated in terms of the local oxide film thickness, the hydrogen diffusion coefficients in the oxide and metal and the hydrogen concentration in the oxide at the gas-oxide interface. The time to precipitate hydride at any location is calculated by assuming that precipitation occurs once the hydrogen concentration in the metal attains the terminal solubility limit of the metal at the prevalent temperature. The model is compatible with the reported temperature and pressure dependence of the hydride induction time. The model can also explain observations such as precipitation of hydride at or beneath the oxide-metal interface and the arrested growth of hydride sites. Finally, an expression is derived for the number of hydride sites initiated on an entire sample surface in any given time by assuming a Gaussian oxide film thickness distribution over the entire sample surface. © 2013 Crown Copyright.

Hutchinson M.D.,Atomic Weapons Establishment
Propellants, Explosives, Pyrotechnics | Year: 2012

Previous papers by the author [1, 2] pointed to a discovery by Fisher [3] that an equation by Fano [4], when used to predict blast impulse from cased munitions, did not fit the available data. These previous papers showed that an alternative equation for casing-modified blast impulse could be derived directly from an equation by Gurney [5] for the kinetic energy balance between the mass of casing metal and the mass of explosive gases. However, this equation was derived for very ductile casings that are accelerated to their ideal Gurney velocity before they fracture. Many real casings, even under high dynamic strain rates, fracture before they can receive the full drive available from the explosive gases. This paper shows how the equation in reference [2] can be modified to allow for casing fracture at finite dynamic strain and provides validation for this modified equation from previously unpublished AWE archive experimental data. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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