Ship-hull vs. barge: Stability and seaworthiness

[fimp]

I'm in the process of determining which type of vessel will be most suitable for a project. The first task is choosing between a barge and a shiphull design. The most important criteria is stability, comfortability and seaworthiness.

Can you make some general comments about the stability, comfortability and seaworthiness of a barge versus a ship hull of similar length and tonnage? Is it generally more comfortable to be on a barge than on a ship during the same kind of weather? Will the barge have less rolling motion? Will a ship be able to handle larger waves than a similar sized barge before capsizing?

[DCockey]

Are you a student? Is this a homework assignment or related to a project?

[fimp]

I'm a student of mechanical engineering, but the project is not university related.

[BPL]

Flat barges are best in calm conditions.

[PAR]

If seaworthiness is anywhere in the equation, then an appropriate hull form is necessary, so toss the barge shapes out the window. The same would be true of the other two requirements you've listed as the phrase "sails like a barge" or "handles like a barge" isn't just a cute or derogative comment; it's really based in the realities of that hull form.

[fimp]

Originally Posted by PAR

If seaworthiness is anywhere in the equation, then an appropriate hull form is necessary, so toss the barge shapes out the window. The same would be true of the other two requirements you've listed as the phrase "sails like a barge" or "handles like a barge" isn't just a cute or derogative comment; it's really based in the realities of that hull form.

I have used "seaworthy" in the meaning of the ability to avoid sinking or capsizing. Is this also the meaning you're using - or can seaworthy also mean the ability to travel fast, i.e. low drag?

[PAR]

Seaworthiness is a huge set of variables, which is dictated by the design SOR. Low drag and speed typically aren't part of the equation, though can have significant impacts on the decisions and compromises accepted in the design. Barges generally have a high initial stability range, but then drop off a cliff, past a modest angle. There's no such thing as a fast barge, unless Cleopatra has risen from the dead and summoned her servants. Generally, a barge is a bulk carrier and very little else. You can dress it up to be something it's not, but she'll still be a pig in a silk dress.

[daiquiri]

Check this: Seaworthiness

This is a nice and short article about seaworthiness: http://www.888-go-longy.com/legal-de...worthiness.php

[fimp]

Originally Posted by BPL

Flat barges are best in calm conditions.

Originally Posted by PAR

Seaworthiness is a huge set of variables, which is dictated by the design SOR. Low drag and speed typically aren't part of the equation, though can have significant impacts on the decisions and compromises accepted in the design. Barges generally have a high initial stability range, but then drop off a cliff, past a modest angle. There's no such thing as a fast barge, unless Cleopatra has risen from the dead and summoned her servants. Generally, a barge is a bulk carrier and very little else. You can dress it up to be something it's not, but she'll still be a pig in a silk dress.

Thanks. So what you're saying is that:

Mild waves and wind: Barge is equally comfortable or more comfortable than a ship.
Harsh waves and wind: Ship is more comfortable than a barge.

Is this a correct interpretation?

[gonzo]

fimp: can you define what you call a ship? Engineering is a precise language. Unless you narrow the question, this whole thread won't make much sense.

[fimp]

Originally Posted by gonzo

fimp: can you define what you call a ship? Engineering is a precise language. Unless you narrow the question, this whole thread won't make much sense.

A mid-size cruise ship, ~150-200m length.

The alternative barge could be one like the Camelot.

[BPL]

Define harsh and mild.