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Defense Programs

Predictive Science and Program Credibility: “Beyond M over U”

July 2008

Njema Frazier, PhD

Acting Deputy Director, Office of Advanced Simulation and Computing

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Defense Programs

Stockpile Stewardship Program Decision-Basis

Computing

Ut

F U S U

Lc U 0

Simulation

Integrated experiments,UGT database

SurveillanceScience,

Small-scale experiments, Subcrits

Theory

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Defense Programs

Balancing Act in building Confidence

• Representing the Science

– Hydrodynamics

– Turbulence

– Equations of State

– Neutron Chain Reactions

– Material Properties, Strengths

– Shocks and Material Interfaces

– Material Deformation, Plastic Flow

– Nuclear and Thermonuclear Reactions

– Electronics. Electrical Systems

– Energetic Materials, Chemical Reactions

– Heat Flow

– Opacities

– Magneto-hydrodynamics

– Plasmas

– Lasers

– Radiation and Charged Particle Transport

• Solving the Problems

– LEPs

– SFIs

– Engineering

– Safety

– Threat Reduction

– Secure Transportation

– ICF

• Supplying the Tools

– Codes

– Models

– Platforms

– Vis Capabilities

– Expertise

– Facilities

– QMU

Undervalued Tool in building Confidence: A Sound Methodology for identifying, quantifying, understanding, and driving down uncertainties

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Defense Programs

National Decision-Basis

Computing

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Defense Programs

Delivery of Validated Tools

• We Know all the Science present

• We Understand all the Science present

• We Understand how all the Science behaves in all our Systems

• We Understand how all the Science would behave with variations on our Systems

• We have identified the key Science phenomena present

• We Understand most of the key Science present

• We Understand how most of the key Science behaves in our Systems

• We Understand how most of the key Science would behave with minor variations on our Systems

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Defense Programs

Balancing Act in building Confidence

• Scientific Approach

– Systematic– Directed– Based on Core Methodologies– Rigorous testing

• Sound Results

– Reproducible– Consistent– Understandable

• Well Understood Uncertainties

– Error Bounds– Physical-basis for free parameters– Relationship between

approximations and exact solutions– Identification of Single and

Aggregate Uncertainties

• Measures of Progress

– Predictive Capability Framework– V&V Assessments– Milestones– External Reviews– Reduced Uncertainties in baselines– Increased usage

Looking to build confidence in Methodologies and Measures

…in addition to tools, people, and direction.

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Defense Programs