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Advanced Applications of Adifor 3.0 for Efficient Calculation of First-and Second-Order CFD Sensitivity DerivativesThis final report will document the accomplishments of the work of this project. 1) The incremental-iterative (II) form of the reverse-mode (adjoint) method for computing first-order (FO) aerodynamic sensitivity derivatives (SDs) has been successfully implemented and tested in a 2D CFD code (called ANSERS) using the reverse-mode capability of ADIFOR 3.0. These preceding results compared very well with similar SDS computed via a black-box (BB) application of the reverse-mode capability of ADIFOR 3.0, and also with similar SDs calculated via the method of finite differences. 2) Second-order (SO) SDs have been implemented in the 2D ASNWERS code using the very efficient strategy that was originally proposed (but not previously tested) of Reference 3, Appendix A. Furthermore, these SO SOs have been validated for accuracy and computational efficiency. 3) Studies were conducted in Quasi-1D and 2D concerning the smoothness (or lack of smoothness) of the FO and SO SD's for flows with shock waves. The phenomenon is documented in the publications of this study (listed subsequently), however, the specific numerical mechanism which is responsible for this unsmoothness phenomenon was not discovered. 4) The FO and SO derivatives for Quasi-1D and 2D flows were applied to predict aerodynamic design uncertainties, and were also applied in robust design optimization studies.
Document ID
20050050933
Acquisition Source
Headquarters
Document Type
Other
Authors
Taylor, Arthur C., III
(Old Dominion Univ. Norfolk, VA, United States)
Date Acquired
September 7, 2013
Publication Date
November 23, 2004
Subject Category
Aerodynamics
Funding Number(s)
PROJECT: ODURF Proj. 111451
CONTRACT_GRANT: NCC1-01015
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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