AUTOMATIC DIFFERENTIATION OF AN EULERIAN HYDROCODE
Abstract
Automatic differentiation (AD) is applied to a two-dimensional Eulerian hydrodynamics computer code (hydrocode) to provide gradients that will be used for design optimization and uncertainty analysis. We examine AD in both the forward and adjoint (reverse) mode using Automatic Differentiation of Fortran (ADIFOR, version 3.0). Setup time, accuracy, and run times are described for three problems. The test set consists of a one-dimensional shock-propagation problem, a two-dimensional metal-jet-formation problem and a two-dimensional shell-collapse problem. Setup time for ADIFOR was approximately one month starting from a simplified, fixed-dimension version of the original code. ADIFOR produced accurate (as compared to finite difference) gradients in both modes for all of the problems. These test problems had 17 independent variables. We find that the forward mode is up to 39% slower and the adjoint mode is at least 11% faster than finding the gradient by means of finite differences. Problems of real interest will certainly have more independent variables. The adjoint mode is thus favored since the computational time increases only slightly for additional independent variables.
- Authors:
- Publication Date:
- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Org.:
- US Department of Energy (US)
- OSTI Identifier:
- 767469
- Report Number(s):
- LA-UR-00-5453
TRN: AH200123%%231
- DOE Contract Number:
- W-7405-ENG-36
- Resource Type:
- Conference
- Resource Relation:
- Conference: Conference title not supplied, Conference location not supplied, Conference dates not supplied; Other Information: PBD: 1 Nov 2000
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ACCURACY; COMPUTER CODES; DESIGN; FORTRAN; HYDRODYNAMICS; OPTIMIZATION
Citation Formats
HENNINGER, R, CARLE, A, and MAUDLIN, P. AUTOMATIC DIFFERENTIATION OF AN EULERIAN HYDROCODE. United States: N. p., 2000.
Web.
HENNINGER, R, CARLE, A, & MAUDLIN, P. AUTOMATIC DIFFERENTIATION OF AN EULERIAN HYDROCODE. United States.
HENNINGER, R, CARLE, A, and MAUDLIN, P. 2000.
"AUTOMATIC DIFFERENTIATION OF AN EULERIAN HYDROCODE". United States. https://www.osti.gov/servlets/purl/767469.
@article{osti_767469,
title = {AUTOMATIC DIFFERENTIATION OF AN EULERIAN HYDROCODE},
author = {HENNINGER, R and CARLE, A and MAUDLIN, P},
abstractNote = {Automatic differentiation (AD) is applied to a two-dimensional Eulerian hydrodynamics computer code (hydrocode) to provide gradients that will be used for design optimization and uncertainty analysis. We examine AD in both the forward and adjoint (reverse) mode using Automatic Differentiation of Fortran (ADIFOR, version 3.0). Setup time, accuracy, and run times are described for three problems. The test set consists of a one-dimensional shock-propagation problem, a two-dimensional metal-jet-formation problem and a two-dimensional shell-collapse problem. Setup time for ADIFOR was approximately one month starting from a simplified, fixed-dimension version of the original code. ADIFOR produced accurate (as compared to finite difference) gradients in both modes for all of the problems. These test problems had 17 independent variables. We find that the forward mode is up to 39% slower and the adjoint mode is at least 11% faster than finding the gradient by means of finite differences. Problems of real interest will certainly have more independent variables. The adjoint mode is thus favored since the computational time increases only slightly for additional independent variables.},
doi = {},
url = {https://www.osti.gov/biblio/767469},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Nov 01 00:00:00 EST 2000},
month = {Wed Nov 01 00:00:00 EST 2000}
}