Powering/Endurance/Range Module?

[otaku]

Hi,

Is there a demand for a module to handle estimated range and endurance calculations? I think this would be a beautiful extension to add to DELFTship. I hope it is not preempted by patents or other stymying encumbrances.

It would be nice if the extension exploits all the hydros and other model (stability, heel/roll, moving/resistance/draft/trim) information to produce reports (simple or complex, maybe simple for Free, and complex/detailed for Pro). Since not all models will be wall-sided mostly amidships, it would be super to be able to simulate and get reports on these. Also, some nice add-ons might be something such as calm weather, and then other sea-states, and wind resistance information. Bollard Pull/Towing might be over-the-top (hehehe…), but, it might be useful for some designers who want to arrive at the best model they can before having it thrown back at them for hull inefficiency or bad engine selection or so forth.

I realize that other companies make such modules but if DELFTship had one that is rudimentary and useful…

I would love to have something that uses the resistance and stability calcs for various speeds and determines the amount of power (in at least horsepower, kilowatts and other useful measures) required to make a voyage, loiter, burst to speeds for a specified period of time, and then to suggest or allow input of a user-required fuel reserve.

MCR may be useful to some for diesel engines. I realize that for gas turbines, they are most effective at full power and very fuel wasteful at less than full-load. Yet, most of the time (I’m going on here in the naval application), a single engine may be on-the-line most of the time.

But, if the module allows for selection or entry of:

— published rudimentary engine supplier values, or
— user-created table of reasonable minimum and maximum values

so that a user can decide how to refine a hull model and so the user can logically accept penalties for increasing the hull/resistance values, and so on, this would be AWESOME.

Theoretically, this might demand that a number of Pro Extensions already be in place, but if some of these features can be built for Free without exposing or de-valuing the Pro Extensions, it would be nice. On the other hand, I’m getting close to being able to afford (by deferring payments on other obligations) Pro (USD $255.78 for me…).

Imagine being able to use ad-hoc damage cases or list or heel values and so on. One can then reasonably size the fuel bunkers so as to not waste hull space. I can guess (reasonably or optimistically or pessimistically) how much space to allocate for fuel, but if i do it incorrectly, i could have bad tank geometry, which in turn impacts general arrangement, right?

These are just some thoughts for my wishlist for DELFTship. Is it fair to ask that such a module be available at under $200 in Pro, and just rudimentary teaser features for free in Free? Or, maybe there could be pricing for serial-number-controlled individuals vs corporate seats…. I’m an individual, a hobbyist, and have shallow pockets, so, $200 or so is my pain threshold.

(Yes, i am anticipating that some will say that various navies of the world will not like this in a readily-accessible tool. However, this is not the 1950s nor the 1980s. These tools just beautifully speed up the calculations and don’t detraction from operational security of any specific naval vessel unless the operators divulge the fuel status and plant condition information, which they should not do. As for commercial operators, for competitive reasons, they are loathe to divulge too much data, even in view of Copenhagen talks and all the effort of “going green” and spinning for PR reasons. But, for us hobbyists and those making real money providing worthwhile designs, powering and range calculations would be a very, very nice professional extensions.

Besides, look at page 19 and others of the following student paper:

http://www.aoe.vt.edu/~brown/VTShipDesign/2007ADFTeam5DraftReport.pdf

Vastly more such information is in the public, so it cannot be much of a security matter in the academic and non-operational realm for naval hulls not actually in service.)

[otaku]

Adding/Replying to my post:

I just realized that an item of difficulty might be in basic assumptions of propeller design and efficiency. I don’t know whether or how DELFTship assumes anything about propellers when it does the resistance calcs. Maybe these are simulations of a towed model having no propeller appendage? Since each prop is hull design specific, maybe a module to allow for ranges of efficiency would be useful, such as 75% through 90% for traditional props, and some other, reasonable values for ducted/tunnel/azipod types of propulsion.

[Author]

Posts