Nicholson 32 Hull simulation

As simulated using "hullform" program from hullform.com (offline, but possibly accessible through the wayback machine, including the software) using ship's lines from C&N drawings.

Disclaimers:

1. Rudder shape is not properly specified
2. I don't really know what I'm doing - I am not a naval architect

Downloadable Files:

• Lines from drawing no. A.284, lines from drawing no. A.575 ( feet-inches-eighths )
• Lines converted to decimal inches, comments stripped, converted to feet and decimals as input to hullform
• Hullform data file, with transom specified (AP section)
• hullform output (general), hullform output (centres)
• calculated resistance curves (in tons, 0-8kt) (different curves are from different formulae)
• calculated resistance curves (in tons, 0-5kt)
• plots for draft, freeboard, GZ, MCT, Wetted surface
• VRML model

See Hullform manual (PDF) for glossary or here

Methodology

• Ship's lines entered from text on N32 drawings A.284, A.575
  These are in the form feet-inches-eighths e.g. 2-3-5 is 2' 3 5/8".
• Lines converted to decimal feet (e.g. 4.56') suitable for input to the "hullform" program.
  (I could have used a spreadsheet for this, but used a custom Perl script as I find that easier. The text files are tab-separated and can be easily read by spreadsheet programs)
• Data entered to "hullform" as "import text file"
• Added an extra section (9a) to improve the shape of the rudder. It just be my imperfect understanding of the process that required this.
• Entered displacement from specifications, guessed values for LCG and VCG. Ran "balance hull", adjust LCG for spec. waterline
• Plot drag curves.
• I did not make the recommended fine-tuning of hull shape suggested in the manual. This would have moved away from the actual ship's lines, and in any case requires some care to do properly.