The APIs isolate the application developer in one library from changes in another library. By using the reusable-library model, a number of grid generation and visualization subsystem components, including SolidMesh (unstructured grid generator), GUM-B (structured grid generator), and DIVA (solution visualization) have been incorporated into the CFS system.

Graphics and the user interface are the issues of most concern when considering portability between computer platforms. The graphics server API abstracts the application programmer from a specific graphics language. OpenInventor has been used as the primary graphics language for the graphics server due to its portability across multiple platforms, including UNIX workstations and PCs. All user-interface activities are handled through the GuiDe API and are implemented in X Windows/Motif.

3.0 EXAMPLE NUMERICAL RESULTS

A few example numerical results are presented and discussed in this section. These results are for submarines, surface ships, and propulsors. The submarine results include a rotating propeller, so in this context, the body and propulsor are coupled in their natural interaction mode, including crashback. However, there will also be a few results given on an isolated propulsor because there is a good set of experimental data with which to compare.

3.1 Submarines

The submarine configuration considered here is the so-called SUBOFF geometry [51]. Numerous comparisons have been made with this configuration over the past few years. There are various appended configurations that include the bare hull, the bare hull with four stern appendages, and the bare hull with the sail. All of these configurations were considered in [52]. Numerous solutions at several angles of drift were computed and compared to experimental data in [52] [33] using the Baldwin-Lomax turbulence model. The results of this exercise resulted in extremely good agreement with experimental data, much better than one might expect, even to 18 degrees of drift. An example of this agreement is given in Figure 1 where the axial, normal, and pitching moment coefficients are compared with experimental data for the SUBOFF bare hull with four stern appendages.

Figure 1. Numerical and Experimental Data Comparisons for the SUBOFF Body with Four Stern Appendages



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