Hull Distortion

Used to distort a patch (derived from a britfair file) through Lackenby’s method. It enables the variation of the block coefficient, longitudinal center of buoyancy and lengths of the parallel midbody in the fore and aft bodies.

Distort a Hull Patch

1. Select the patch to be distorted by either:

   • Selecting Pick then interactively selecting the patch in a view, or

   • Dragging the required patch from the tree view and dropping it on the Pick button.

   The ID of the current basis patch is displayed.

2. Review the calculated parameters (Cb, LCB, PMB Aft and PMB Fwd) of the basis patch for the specified Draft and Trim.

   1. If a different draft is required, enter the required values and click Update, which forces the SAC to be regenerated.

   2. The SAC curve can be viewed by clicking View SAC....

3. To try a particular distortion:

   1. Select the appropriate options (Cb, LCB, PMB Aft and/or PMB Fwd) for the parameters to change.

   2. Enter the required target values.

   3. Select Distort.

      A new SAC is generated (which can be viewed) and the Achieved values displayed.

      Note: The patch is not distorted until Apply is selected. This step may be repeated with different target parameters until the desired distortion is achieved.

4. If required, select Regenerate Internals before selecting Apply to regenerate all internals for the newly distorted patch.

5. Select Apply.