An Incremental Strategy for Calculating Consistent Discrete CFD sensitivity Derivatives
Abstract
In this preliminary study involving advanced CFD codes, an incremental formulation, also known as the delta or 'correction' form, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For typical problems in 2D, a direct solution method can be applied to these linear equations in either the standard or the incremental form, in which case the two are equivalent. Rerative methods appear to be needed for future 3D applications, however, where direct solver methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form result in certain difficulties, such as ill-conditioning of the coefficient matrices, which can be overcome when these equations are cast in the incremental form; these and other benefits are discussed herein. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two laminar sample problems: (1) transonic flow through a double-throat nozzle, and (2) flow over an isolated airfoil.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1992
- Accession Number
- ADA251688
Entities
People
- Arthur C. Taylor Iii
- Gene W. Hou
- Henry E. Jones
- Perry A. Newman
- Vamshi M. Korivi
Organizations
- Langley Research Center