NavCAD 2011

For those interested:

http://www.hydrocompinc.com/navcad2011/overview.htm

http://www.hydrocompinc.com/propelements/default.htm

 

It seems to me, from exploring and using Freeship, that, changing the draft as part of the iterative or regression steps would be really useful.

I explored various powering, prop diameters, and so on, but when I manually changed the draft as part of resistance calcs, and manually as part of powering calcs, I could appreciate that going from 8 meters to 6 meters and (hopefully the stability criteria not violated dangerously), the resistance drops significantly.

Since the powering requirements or rather, power required, to move the vessel at the same or faster speeds is not as great, it seems to me that naval or merchant/container ships could benefit from having fins and underway blowable ballast tanks gradually decrease their wetted surfaces if the sea states are permitting and no sudden or constant and large ruder angles are ordered. This would be one way to greatly increase range. But, I figure that the power to do this would cost in fuel, and the tanks needed would need to be a subdivided many so the discharge pumps or air blowers won't need to be massively powerful.

Has this been approached, or deemed infeasible?


"Has this been approached, or deemed infeasible?"

Strike that ... I just saw a ballast photo and realized that THAT question needn't have been asked. It seems the emissions reductions efforts are driving (or are increasing the driving of) variable ballasting and trimming for fuel optimizations more than I remembered.

 

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http://www.fathomshipping.com/sneak-peek.pdf

Page 13


http://www.km.kongsberg.com/ks/web/nokbg0397.nsf/AllWeb/302A1A3175AB5D4DC12574CC0045D82A/$file/KM-Vessel-performance.pdf?OpenElement

page 11 made me think of Star Trek dilithium crystals

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