Virtual Marine Arsenal

Flotilla is a computer workbench that can be used for investigations into some aspects of ship hydrodynamics. Flotilla is not suitable for many classes of hulls. It cannot handle planing hulls or very stubby vessels like tugboats. However, it provides very acceptable predictions for hulls with L/B as low as 5 when the hull has a transom stern.

It is a difficult program for newcomers to hull design, and a familiarity with the Naval Architecture is crucial. Some familiarity with ship hydrodynamics will be an advantage.

Flotilla is an enhanced thin-ship code using linear wave theory. It can be used to estimate the resistance, squat and wave patterns of monohulls, catamarans and surface effect ships (SES). The free version only supports monohulls though.

The standard input method for Flotilla uses collections of small text files as input. Flotilla has no graphics capabilities itself. Results are contained in comma-separated text files that can be read by third-party software such as gnumeric, Scilab, or gnuplot.

There are many opportunities to waste a lot of computer time and human effort with Flotilla. Incorrect specification of parameters in input files will result in completely useless output and it is imperative that users gain familiarity with the input files and their nuances.

Flotilla uses short batch files to assemble input, run executables, and collate input. Examples are provided that can serve as templates for your own projects, however, some knowledge of basic DOS commands (like “copy” and “cd”) and directory structures will be very useful.