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Dickens, Thomas P.

Publications and source records attributed to Dickens, Thomas P..

Cooperative solutions coupling a geometry engine and adaptive solver codes

Follow-on work has progressed in using Aero Grid and Paneling System (AGPS), a geometry and visualization system, as a dynamic real time geometry monitor, manipulator, and interrogator for other codes. In particular, AGPS has been successfully coupled with adaptive flow solvers which iterate, refining the grid in areas of interest, and continuing on to a solution. With the coupling to the geometry engine, the new grids represent the actual geometry much more accurately since they are derived directly from the geometry and do not use refits to the first-cut grids. Additional work has been done with design runs where the geometric shape is modified to achieve a desired result. Various constraints are used to point the solution in a reasonable direction which also more closely satisfies the desired results. Concepts and techniques are presented, as well as examples of sample case studies. Issues such as distributed operation of the cooperative codes versus running all codes locally and pre-calculation for performance are discussed. Future directions are considered which will build on these techniques in light of changing computer environments.

Dickens, Thomas P.

Technique for using a geometry and visualization system to monitor and manipulate information in other codes

A technique was developed to allow the Aero Grid and Paneling System (AGPS), a geometry and visualization system, to be used as a dynamic real-time geometry monitor, manipulator, and interrogator for other codes. This technique involves the direct connection of AGPS with one or more external codes through the use of Unix pipes. AGPS has several commands that control communication with the external program. The external program uses several special subroutines that allow simple, direct communication with AGPS. The external program creates AGPS command lines and transmits the line over the pipes or communicates on a subroutine level. AGPS executes the commands, displays graphics/geometry information, and transmits the required solutions back to the external program. The basic ideas discussed in this paper could easily be implemented in other graphics/geometry systems currently in use or under development.

Dickens, Thomas P.