www'sandia'govNNSArussia

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RussianCollaborations

• www.sandia.gov/NNSA/russia/

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Oleg SchillingLawrence Livermore National
LaboratoryASC Principal Investigators
Meeting26 February, Monterey, CA

• Overview of Collaborations Between LLNL and
  Russian Federation Institutes

Zababakhin Scientific Talks, Snezhinsk 2007
This work was performed under the auspices of the
U.S. Department of Energy by Lawrence Livermore
National Laboratory under Contract
DE-AC52-07NA27344
LLNL-PRES-401247
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• LLNL maintains a portfolio of collaborations with
  the RF in computational and material science

• We are broadly engaging scientists at our
  counterpart Laboratories (VNIIEF, Sarov and
  VNIITF, Snezhinsk)
• Over the years we have executed projects
  involving simulations, experiments, and theory
• Simulation projects of interest to ASC include
• Hybrid Structured/Unstructured Mesh Hydrodynamics
  and Heat Conduction (VNIIEF)
• Refinement/Reconnection in Free-Lagrange
  Simulations (VNIIEF)
• Development/Study of Adaptive Energy/Angle
  Variables for Solving Transport Equations
  (VNIIEF)
• Quantum Mechanical Simulation of Actinides
  (VNIITF)
• MD Simulation of Elastic-Plastic and Spall
  Mechanisms in Dynamically Loaded Cu (VNIITF)
• Analytical Solutions to Test Codes Simulating Gas
  Dynamics and Radiation Transport (VNIITF)

shock
grain boundary
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An experimental/computational collaboration with
VNIIEF has improved constitutive models

• Data from shocked/shockless loading of Al, Cu and
  V with perturbations at strain-rates 104-106 s-1
• Measure influence of dynamic strength on
  instability growth for code/strength model V V
• Simulations provided confidence in the SG and
  PTW strength models

• Detonator
• High explosive
• Vacuum Gap
• Liner
• Sealing cylinder

Liner with imposed perturbations
Rayleigh?Taylor instability growth diagnosed
by side-on radiography
Pressure field from simulation
ARES simulation
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A computational collaboration with VNIIEF is
exploring more efficient adaptive algorithms for
transport

• Discretizing SN transport equation
• in space, direction, and frequency requires Nx
  Ny Nz N? N? N? variables (?109-12 variables in
  3D)
• Adaption in angle or energy can potentially
  accelerate and improve transport algorithms

Insufficient angular resolution geometric
divergence ray effects
Flux from slit test problem with 8, 16, 100
angles and 8 angles with 1st- and 4th-order
adaptivity
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Collaborations with the Russian Federation can
benefit the Laboratory and ASC

• Algorithm development, computational material
  science, and test problem projects can positively
  impact the Program
• Simulation collaborations provide testbeds for
  developing and exploring more efficient methods
  for transport and hydrodynamics
• Synergistic collaboration in experimental and
  computational material science can advance
  physical, constitutive, and multi-scale modeling
  
• Test problem collaborations can add new problems
  to the VV suite
• Our collaborators have pursued computational
  science in parallel with us
• The Laboratories can potentially benefit from
  their novel approaches

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Marvin A. Zocher, Robert E. Reinovsky, James R.
Kamm,Michael F. StevensASCI PI Meeting,
Monterey, CAFeb 26, 2008

• Overview of LANL Participation in the US/Russian
  ST Collaborations

Snezhinsk City Square
Sarov Bell Tower
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• TO 21 (VNIIEF) Ignatova
• Constitutive Behavior and Damage Mechanics

Experimental/Theoretical/Numerical
collaboration Leading to better constitutive and
damage models

• Grain Size Effects
• Localization Effects
• Temporal Softening
• Scaling Effects

SCCM 2007, p. 597, p. 649
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• TO 9 (VNIITF) Dremov
• Molecular Dynamics Studies Shock-Induced
  Microstructure Evolution, Pu Aging

• Initiation and
• Evolution of Damage
• Phys Rev B, Vol 74, No. 14, 2006

• DFT, MD simulations leading to better
  understanding of Pu Aging

• He diffusion
• He bubble formation
• Bubble-bubble interaction
• Self-irradiation damage in Pu lattice already
  containing He and bubbles
• He bubble diffusion
• He bubble stability

Submitted to Phys Rev
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• TO 35 (EF) Zhernokletov, TO 10 (TF) Petrovtsev
• Cerium

Experimental/Theoretical/Numerical
collaboration Leading to better understanding of
phase mechanics, phase change kinetics,
multiphase models
Ce is an interesting material

• Complex Phase Diagram
• Four solid phases at zero pressure at least 3
  more at pressure gt 0
• ?-phase has negative bulk modulus
• Solid-solid critical point
• Large volume collapse (15) on ?-? transition
• Large regions of phase diagram uncertain
• Anomalous melting at low pressure
• Complex electronic behavior

SCCM 2007, p. 105, p. 117
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• TO 24 (VNIIEF) Boyko
• Damage Mechanisms in Cylindrically Convergent
  Geometry

Experimental/Theoretical/Numerical
collaboration employing a unique driver developed
by VNIIEF aimed at gaining a better understanding
of post-damage recollection and recompression
Magnetic (pulsed power) driven cylindrical implosi
ons provide both highly precise shock-induced
damage AND sufficient reacceleration of the
damaged surface to overtake and recollect
damaged material Valuable date on damage
initiation and evolution including recollection
and recompaction for the development/evaluation
of improved damage models Six of ten planned
experiments complete
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• Summary

LANL has had ongoing involvement for more that 15
years The collaboration has proven to be highly
valuable providing unique experimental data,
unique models, unique numerical methods, unique
problem approaches, access and insight, etc.

• Metrics for Success
• Collaborations are characterized by comparable
  levels of effort by both Russian and American
  researchers
• Collaborations are of mutual interest focused on
  research topics that enhance/support/complement
  the research objectives of both sides
• Collaborations are characterized by parity
  projects are chosen by mutual consent and the
  overall commitment of each side is comparable
• Collaborations are of high scientific merit the
  work stands the test of peer review and generates
  appropriate outputs such as publications,
  conference presentations, and other archival
  value documents, etc., as appropriate

How are we doing? At present, metrics 2 and 4 are
satisfactorily being met metrics 1 and 3 are,
in general, not being met.
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Heath L. Hanshaw, John B. AidunSandia National
Laboratories ASC PI Meeting, Monterey CA 26
February 2008
SAND08-0982C

• SNL ASC Science Technology Collaborations with
  Russian Federal Nuclear Centers and Russia
  Academy of Science Institutes

Sandia is a multiprogram laboratory operated by
Sandia Corporation, a Lockheed Martin Company,
for the United States Department of Energy under
contract DE-AC04-94AL85000.
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Sandia staff are leveraging Russian colleagues
expertise to advance ASC project objectives

• SNL is engaged with 9 PIs at 5 institutions in
  research in computer science, HEDP, and
  computational materials
• Federal Nuclear Centers VNIIEF (Sarov) VNIITF
  (Snezhinsk) VNIIA (Moscow).
• Academy of Science Institutes JIHT (Moscow)
  IPME (St. Petersburg).
• Benefits of these collaborations
• Alternative approaches to problems
• Access to world-class experts in areas of NNSA
  interest
• Access to unique and valuable technology
• Technical advances.

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6 SNL-Russia projects cover topics ofComputer
Science and HEDP

• Computer Science N. Pundit w/ ITMF/VNIIEF
• Scalability of parallel algorithms
• Interconnect effects on code scalability
• Supercomputer efficiency with timing
  instabilities.
• HEDP Pulsed Power H. Hanshaw
• MHD simulation of Z- and Z-Q pinches (VNIIEF)
• Simulation of wire array implosions (VNIITF)
• Hybrid code for PetaWatt laser/dense plasma
  interaction (VNIITF).

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6 SNL-Russia projects cover topics
inComputational Materials

• MD study of phonon generation during cracking
• E.P. Chen w/ ITMF/VNIIEF
• Platform-independent molecular builder
  visualizer
• J.Aidun w/ ITMF/VNIIEF
• Modeling thermal decomposition of polymeric
  materials
• K. Erickson w/ VNIIA
• MD study of phonon generation by laser excitation
• E.P.Chen w/ IPME
• Performance reliability of MEMS
• E.P.Chen w/ IPME
• Extending non-equilibrium MD methods
• A.Thompson w/ JIHT

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SNL-Russia Project Highlights

• G.E.Norman (JIHT) invited to talk at SCCM07
  Atomistic simulation of plasticity, spall damage
  and fracture of crystalline and polycrystalline
  metals under high strain rate.
• Providing insights on dynamic strength and
  damage.
• VNIIA-Mendeleyev U.-VNIIPO-SNL joint paper
  Thermal Decomposition Mechanism of PMDI-Based
  Polyurethane Foam Studied by Multiple Methods,
  submitted to J. Polymer Degradation and Stability
  
• Unique experimental capability and expertise
  advancing the science of foam decomposition.
• VNIIEF Comp.Sci. researchers analytical model
  successfully predicts operating system noise
  effects on the scale of parallelism.
• Laying the groundwork for ever larger scale
  parallelism.
• VNIITF hybrid PIC MHD code reveals importance of
  kinetic effects in the evolution of thermal
  instabilities in Z-Pinches.
• Access to alternative modeling approaches speeds
  discovery.