boat design - art or science?

Linguistics certainly is fascinating, but your conclusion is not really valid. In practice, most people do not know, nor care, about the etymology and history of the meaning of a word when they use it. When someone uses the word "science" today it makes no difference what the Romans thought the term implied 2000 years ago.

Leo.

 

I agree, few people care about the original impressions or usages, but how much has it actually changed?

Unless I'm much mistaken, sciences are still considered to be a deeper understanding of (an aspect of) a problem.

Besides, now you can be informed about the language you use. It may not be of much use, but then again....

Tim B.

 

Some of the finest yachts ever conceived, weren't bellied around with a virtual panning tool. In fact these craft were understood to be beautiful, just by their plan, profile and section drawings, to those that penned them or understood the lines. Many fast, weatherly and able vessels, perform incredibly and are butt ugly, even if quite functional.

An engineer is structurally educated and experienced, a businessman has successfully kept themselves fed and an artist is the one who sees a yacht's wake and instantly understands how the boat will perform and why, because they've developed what few have had enough experience to, an eye. Not for the beauty of the thing, but that good form will provide good function, particularly if the businessman and engineer in them permits sufficient latitude to provide some grace to the form.

 

So why did artists miss the existence of boundary layers for hundreds of years? Can artists see the vortices behind bird wings?

 

Da Vinci did see vortices in both bird wings (through smoke I'd guess) and with his extensive experiments with water. He clearly noted both in severial drawings.

 

I've seen a couple of very early drawings with vortices behind people's legs when they were standing in water. But noticing is only part of the story. The key is to relate those vortices to drag losses, or in the case of sharp-edged wings, the additional lift that might result if leading-edge vortices reattach on the top surface. Artist schmartist, I say. They are, at best, only good for choosing the colour scheme of a boat

 

Boat design is for me a compromise between art and engineering.
Very often the rule is to put in the yacht a lot of beds and only then design all around the hull....

The boat is beautiful but....only to take a drink at port.

 

An interesting argument, long debated. I've come to the conclusion that 'art', at the least in terms of what is 'pleasing to the eye', cannot be entirely ignored at the expense of 'form follows function'. To wit, one of my favorite examples follows and both vessels 'hit the water' at approximately the same time, so the comparison is valid in the sense that one would have to assume that all facets of both art and pure science/technology, that are (or are not) evidenced in each, coexisted.

The 'worlds fastest megayacht'...as once claimed anyway..



The worlds most efficient high-speed vessel in it's size range:



The first relies in a hull design akin to a Hickman sled with a point stuck on it and thus has motions that will cause injury when operating at 50 knots in a 2 foot chop (not kidding..been there). At 116' LOA and roughly 100 tons, it made a little over 60 knots using two 16V396 MTU diesels and one TF40 gas trubine, all through KaMeWa jsts.

The second, an SES of 160' LOA and 220 tons, achieved 47 knots with only the two MTU 39616Vs and two 6V396 lift engines and would have achieved over 60 knots with same power as installed in the 100-ton yacht. Of more importance in my mind than the fact that we're talking twice the displacement as the yacht, the SES motions were acceptable, even under fairly high sea conditions in which the yacht would barely manage to slog through.

Post-script: The turbine has long ago been removed from that yacht and it now makes 35 knots with the twin 16V396 diesels.

The moral of the story?...the yacht 'looks' like a killer performance machine..the SES looks..well..just plain ugly. So in the years since both were on the scene, many Moonraker look-a-likes have been built and more will be; many with the same horrible hull designs..but very few vessels based on the SES and certainly none that were 'yachts' The superior performance of the vessel based only on 'best engineering and science' principles is not what people want to look at, own or operate apparently.

We've always lamented that we fail to find ways to do both well. If we could do so...the 'worlds fastest megayacht' would be once heck of a lot faster than they are now.

 

Maybe the SES just needs the touch of a good Industrial Designer (or Architect) to make it more visually pleasing.

Link on that topic:
http://www.boatdesign.net/forums/showthread.php?t=16012

 

Yeah, change the colour. Grey is so drab...

Ship design is definitely science, not art. Boat design? At the AC end, still science, at the dinghy end, I'd say science - with a lot of intuition rather than hard facts, and a bit of artistic styling sometimes thrown in.

 

First step is to get rid of the humans on board. Most of that visual clutter above the waterline is to cater for fragile bags of water who need to see where the ship is going. High speed-vessels like that should be operated by robots. Think of the weight-savings for a start. And for SES, the cobblestone effect can't turn their kidneys into mush.

Then again, I'm not sure if I'd trust either humans or robots to operate a 20,000 ton SES travelling at 60 knots or more.

Leo.

 

LMAO. Great points. (Killer program you created in Michlet btw..kudos. It's recently served us well in a couple of problematic design tasks. Waiting breathlessly for R 2.0)

And what 'cobblestone effect'? I killed that little problem years ago.

-Bill

 

All you have to do is take most of the mass out (weight) and lower the cushion pressure to almost zero - problem solved!

 

No no no. Tsk. You need only to supply massless air. Fortunately for my pocket book, the workable solution actually involves lots of fancy hydraulically-operated hihg-response cushion vent louvers (and/or variable-geometry lift fans) and a detailed knowledge of the spatial pressure responses, particularly those that are acoustic, and the ability to build a controller that can effectively resolve the whole mess through various filters originated by Kalman and others and kill the fundamental heave-bounce mode of the rather lively spring that is known, oxymoronically, as an air 'cushion'. (whew! that was a long sentence..) A 'cushion' it ain't...

 

Excellent news! That means you probably have lots of time to consider other difficult problems.

What do you think of the idea of an SES with a number of (typically three) sub-cushions, each at a different pressure?

Do you think that it is possible to have significantly different pressures? Or will leakage under the sub-cushions mean that the pressure will tend to be fairly even at the water surface?

Best of weekends to you all!
Leo.