Code Differentiation for Hydrodynamic Model Optimization

Henninger, R J; Maudlin, P J

Title: Code Differentiation for Hydrodynamic Model Optimization

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Abstract

Use of a hydrodynamics code for experimental data fitting purposes (an optimization problem) requires information about how a computed result changes when the model parameters change. These so-called sensitivities provide the gradient that determines the search direction for modifying the parameters to find an optimal result. Here, the authors apply code-based automatic differentiation (AD) techniques applied in the forward and adjoint modes to two problems with 12 parameters to obtain these gradients and compare the computational efficiency and accuracy of the various methods. They fit the pressure trace from a one-dimensional flyer-plate experiment and examine the accuracy for a two-dimensional jet-formation problem. For the flyer-plate experiment, the adjoint mode requires similar or less computer time than the forward methods. Additional parameters will not change the adjoint mode run time appreciably, which is a distinct advantage for this method. Obtaining ''accurate'' sensitivities for the j et problem parameters remains problematic.

Authors:: Henninger, R J; Maudlin, P J

Publication Date:: Sun Jun 27 00:00:00 EDT 1999

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Office of Defense Programs (DP) (US)

OSTI Identifier:: 759173

Report Number(s):: LA-UR-99-3075
TRN: US0004312

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Conference

Resource Relation:: Conference: American Physical Society Conference on Shock Compression of Condensed Matter, Snowbird, UT (US), 06/27/1999--07/02/1999; Other Information: PBD: 27 Jun 1999

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACCURACY; EFFICIENCY; HYDRODYNAMIC MODEL; HYDRODYNAMICS; OPTIMIZATION

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                    Henninger, R J, and Maudlin, P J. Code Differentiation for Hydrodynamic Model Optimization.  United States: N. p., 1999. 
        Web.

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                    Henninger, R J, & Maudlin, P J. Code Differentiation for Hydrodynamic Model Optimization.  United States.

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                    Henninger, R J, and Maudlin, P J. 1999.  
        "Code Differentiation for Hydrodynamic Model Optimization".  United States.  https://www.osti.gov/servlets/purl/759173.

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@article{osti_759173,

  title        = {Code Differentiation for Hydrodynamic Model Optimization},

  author       = {Henninger, R J and Maudlin, P J},

  abstractNote = {Use of a hydrodynamics code for experimental data fitting purposes (an optimization problem) requires information about how a computed result changes when the model parameters change. These so-called sensitivities provide the gradient that determines the search direction for modifying the parameters to find an optimal result. Here, the authors apply code-based automatic differentiation (AD) techniques applied in the forward and adjoint modes to two problems with 12 parameters to obtain these gradients and compare the computational efficiency and accuracy of the various methods. They fit the pressure trace from a one-dimensional flyer-plate experiment and examine the accuracy for a two-dimensional jet-formation problem. For the flyer-plate experiment, the adjoint mode requires similar or less computer time than the forward methods. Additional parameters will not change the adjoint mode run time appreciably, which is a distinct advantage for this method. Obtaining ''accurate'' sensitivities for the j et problem parameters remains problematic.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/759173},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun Jun 27 00:00:00 EDT 1999},

  month        = {Sun Jun 27 00:00:00 EDT 1999}

}

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