Attachment 4 - TO 3 TA - 14

LASER EFFECTS ASSESSMENT, MODELING, AND RESEARCH (LEAMR)

Technical Area 14: Laser Target Interaction Modeling and Simulation Task Order #3 “Physics-based Modeling for Laser Effects Research” 16 April 2014

1. SCOPE

To develop physics based models that accurately predict the target response during laser irradiation to quantify susceptibility and improve the understanding of target vulnerabilities. To perform parametric studies for analyzing the laser performance trade space and uncertainty quantification for tracking solution uncertainties. To identify governing physical processes necessary to represent the target response and simplify physics-based models to an engineering level such that they can be integrated in engagement and mission level models. The scope of this Task Order (TO) includes program plan development, coordination with experimental programs, development of measurement error budgets, data reduction and analysis, physics and engineering model development and enhancements, uncertainty quantification, documentation, as well as optimizing the use of software, databases, and computer hardware for physics based simulations.

2. TECHNICAL REQUIREMENTS

Develop and apply physics-based models that predict the target response during laser irradiation and quantifying susceptibility requirements and laser effectiveness thresholds. The model development research will be used for verification and validation of models for intended use cases, parametric studies for analyzing the laser performance trade space, uncertainty quantification for tracking laser requirement uncertainties, identification of governing physical processes necessary to simplify physics-based models to an engineering level such that they can be integrated with engagement and mission level models, coordination with experimental programs to develop measurement error budgets to maximize the utility of experimental efforts for the development and validation of physics and engineering level models. The contractor should address how they propose to accomplish the following areas for laser/material interaction modeling and simulation research:

2.1. Develop and Demonstrate State-of-the-Art Physics-based Models for Predicting Laser Effects (CDRLs A001, A004, A005, A006, and A013):

· Perform research and development in advanced numerical modeling techniques such as; the finite element method, finite volume method, particle methods, hydrodynamics and related methods for performing computational fluid dynamics, heat transfer, stress analysis, and reaction chemistry for the development of predictive models for laser interaction and target effects.

· Conduct research to develop the capability to accurately predict the effect of a laser on materials commonly used in ground, air, and space systems.

· Perform research to develop physics-based models for simulating the effect of high intensity pulse lasers on materials to include the phenomenology of laser absorption, plasma generation, recoil pressure, phase explosion, gas dynamics of the vapor, and liquid phase expulsion for the prediction of drilling efficiency of pulsed laser systems.

· Perform research to develop physics-based models for penetration of materials using continuous wave lasers to include the phenomenology of laser absorption, molten material flow, high temperature thermo-physical properties, phase change enthalpy, reaction chemistry, radiative and convective losses on the laser susceptibility requirements.

· Perform research to develop high temperature thermo-mechanical constitutive models for predicting high temperature plastic deformation including crack initiation and propagation to analyze the severity of structural failure induced by continuous wave laser heating of structural components.

· Perform research to develop physics-based models to predict the absorption of laser energy in materials that are semi-transparent to the laser wavelength to include the internal scattering and absorption observed in materials such as; composites, ceramics, and thermoplastics to accurately predict laser energy deposition and transient thermal response.

· Perform research to develop coupled physics models for incorporating the interactions between the optical, thermal, chemical, aero, and mechanical processes for accurately predicting laser target interactions in realistic environments.

· Continue the development and application of existing physics-based models within RDLE and ensure future model development maintains continuity with existing capabilities.

2.2. Model Verification, Validation, and Accreditation (CDRL A004, A007, and A013):

· Perform model verification and validation for physics models and model components developed for predictive laser/material interaction simulations. Utilize analytical, numerical, methods of manufactured solutions, or similar methods to verify proper implementation and experimental data representative of the intended use case for validation of the physics model or model component.

· Perform literature review to identify prior analytical, numerical, or experimental results published by AFRL, Government, industry and academia to optimize the use of existing research in the verification and validation process.

· Provide recommendations for validation experiments when existing data is unavailable and utilize resultant test data for validating physics models for the particular application.

· Support the verification, validation, and accreditation process as necessary to accredit predictive physics models for use by a program office.

2.3. Experimental Coordination and Data Analysis (CDRL A004):

· Coordinate with experimental programs at RDLE, during test readiness reviews, test planning working groups, hot washes, and data reviews, to maximize the utility of the experiment through the development of diagnostic recommendations and measurement error budgets with corresponding justification as the measurement applies to laser susceptibility, target vulnerability, physics and engineering model development and validation.

· Support pretest analysis for establishing test strategies and optimizing the test matrix for reaching experimental objectives and perform simulations during experimental programs to aid in decision making for the remaining experiments.

· Reduce test data as necessary to perform post-test analysis of experiments for model development or validation and provide lessons learned, from a model development and validation perspective, to the experimental teams in order to improve the experimental process with respect to instrumentation issues, error budgets, diagnostic techniques, and future requirements.

2.4. Develop Simplified Physics-Based Solvers for Engineering Models (CDRLs A001, A004, A008, A009, and A013):

· Conduct research and development in advanced numerical modeling techniques for the development of simplified physics-based solvers for predictive engineering models for laser interaction and target effects.

· Identify the key physics which govern the prediction of target susceptibility to laser systems using high fidelity physics solvers and experimental data.

· Reduce the complexity of the physics-based model to an engineering level such that the predictive capability is maintained but the computational efficiency is improved significantly and document the assumptions and range of applicability for which the engineering model may be used.

· Coordinate with Assessments activities under Technical Area -13/Task Order #2 (Attachment 3) to ensure simplified physics models are developed to be compatible with existing and emerging Assessment tools and are addressing assessment requirements.

· Continue the development and application of existing RDLE engineering and physics models including the Integrated Thermal Response ALgorithm (ITRAL) and Finite-elements for Laser Interaction and Penetration (FLIP) solvers, for example.

2.5. Parametric Analysis, Optimization, and Uncertainty Quantification (CDRL A004):

· Conduct parametric studies to evaluate the laser trade space and identify laser vulnerability characteristics such as irradiance thresholds for damage, spot size requirements, and component sure-safe and sure-damage levels.

· Utilize parametric analysis to perform sensitivity studies to identify governing physics and identify parametric correlations to guide research investments in refining model input parameters.

· Conduct optimization studies to evaluate experimental data, perform inverse heat transfer calculations, and optimization applications for laser vulnerability studies.

· Conduct research in uncertainty quantification analyses to propagate measurement uncertainties and model input uncertainties through the physics and engineering level models to ultimately quantify the uncertainty in laser susceptibility requirements.

2.6. Software, Database, and Hardware Maintenance (CDRLs A004 and A009):

· Address how you would provide software version control and distribution control compliant with Department of Defense (DoD) standards for revised and newly developed physics or engineering based models built under this TO. References should include MIL-HDBK-61A(SE) and the AF Software Guidebook (See Attachments to this TO).

· Address how you would maintain physics and engineering solvers including finite element models, finite difference models, and software subroutines, written in languages such as C++, Fortran, Python, and Matlab, to perform laser vulnerability studies, including bug fixes related to physics algorithms, compliance with latest compilers, and developing users, programming, and analyst manuals to accompany software releases.

· Address how you would optimize and maintain the use of physics and engineering level models including physical hardware, networking, cluster computing resources.

3. TRAVEL

Provide a cost estimate for possible travel to support efforts outlined above. For evaluation purposes travel should be for the following trip:

3.1. Trip for two (2) to Huntsville, AL for three (3) days. Include in costing:

· Airfare

· Meals and Incidental Expenses (M&IE) http://www.gsa.gov/portal/content/104877?utm_source=OGP&utm_medium=print-radio&utm_term=perdiem&utm_campaign=shortcuts

· Lodging

· Rental Car

4. OTHER DIRECT COSTS (CLIN 0002)

Provide a list of potential material and equipment requirements with Rough Order of Magnitude (RoM) pricing (fully loaded) not to exceed $75K.

5. SCHEDULE, DATA ITEMS, AND OTHER DELIVERABLES

5.1. Start Work: Date of Approval (DOA)

5.2. End of Technical Effort (ETE): DOA + 12 months

5.3. CDRL A001: Computer Software Product End Items: As required

5.4. CDRL A004: Presentation Material: As required

5.5. CDRL A005: Status Report: As required

5.6. CDRL A006: Technical Report – Study/Services – Scientific and Technical Reports: As required

5.7. CDRL A007: Scientific and Technical Report and Checklist: Draft due 30 days after ETE. Final due 90 days after the ETE.

5.8. CDRL A008: Computer Programming Manual: As required

5.9. CDRL A009: Software User’s Manual: As required

5.10. CDRL A013: Management Plan : As required

6. TASK ORDER OFFICER(S)

· Primary: Darren Luke

· Alternate: David Medina

7. ATTACHMENT(S)

MIL-HDBK-61A(SE)

AF Software Guidebook