Experiences with Automatic Differentiation Applied to a Volume Grid Generation Code

Automatic differentiation (AD) is a methodology for developing reliable sensitivity-enhanced versions of arbitrary computer programs with little human effort. As such, it can vastly accelerate the use of advanced simulation codes in a multidisciplinary design optimization context because the time for generating and verifying derivative codes is greatly reduced. The application of the recently developed automatic differentiation of C programs (ADIC) prototype tool for ANSI-C programs on the coordinate and sensitivity calculator for multidisciplinary design optimization multiblock three-dimensional volume grid generator are reported. The ADIC-generated code can easily be interfaced with Fortran derivative codes generated with the ADIFOR AD tool for Fortran 77 programs; thus providing efe cient sensitivityenhancement techniques for multilanguage, multidiscipline problems.