Questions tagged [naval-engineering]
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Ship sinking prevention device using foam?
I hope that this is the correct StackExchange site for my question.
My question is based on three independent facts:
There is a story that a patent on lifting sunken ships using a foamed polymer (...
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Which type of aircraft carrier is more cost-effective and more reliable in the long run? [closed]
All of the >100,000 tonnes US aircraft carriers are nuclear-powered.
On the other hand, all Chinese and British aircraft carriers are conventional powered.
Which type of aircraft carrier is more ...
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Power requirements for a 50,000 TEU container ship
I understand that this may be incredibly vague, but based on current container ships, does anyone have an idea of how much power a 50,000 TEU (TwentyFoot Equivalent Unit) container ship might require?
...
user10249
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Why aren't there many ships with transom bows?
Transom basically is a flat aft, usually vertical. It reinforces the structure, adds deck area, and because that the flat part is above the waterline, no fluid dynamic is hurt.
The extra deck area is ...
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Maneuverability calculation of a catamaran ship with azimuth thruster?
In a competition about ship prototype performance, my team decided to make a small catamaran ship with azimuth thrusters. This competition was originally about speed contest but due to COVID-19 it was ...
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Wire bearings on actuators on military ships
While reading about the Korvette K130 Braunschweig class of corvettes for the German navy, I noticed that almost all of the weapon systems are held in what I'd call a wire bearing.
I'd like to know ...
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Longtitudinal Centre of Gravity for Ship Cargo
I did a Civil Engineering course some years ago and this question from my textbook, I have found what seems impossible to get the correct answer of 46.2 m for. By putting this question up I am hoping ...
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Describe the replacement flow of water at the stern of a large ship
What is the flow path of water immediately at the stern of a large, deep draft ship (like a container ship 250+m long for example)? Does it fill in the area displaced by the hull from all sides ...
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What is up with the spaced rudders on the SMX-31/Barracuda?
You can see it in the video here for the Barracuda: https://youtu.be/_NZKyvQVRd0?t=124
And here's a pic of the SMX-31: http://www.hisutton.com/images/Fr_SMX-31_cutaway.jpg
What are the advantages ...
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What is the optimal building material for a submarine pressure hull?
I have a difficult and interesting design project to work on and I am trying to get my hands on some ballpark figures from people who know engineering a little better. Help is appreciated!
I am ...
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How are circular portholes mapped onto cylindrical hulls?
When portholes are put into a cylindrical hull, such as of a submarine or an airplane fuselage, is the glass window curved to match the curvature of the cylinder?
And if so, is the porthole wrapped ...
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Why did the Soviet Alfa-class submarines have a titanium hull?
My limited knowledge in engineering tells me:
Titanium is expensive, stronger and heavier than aluminium, lighter and weaker than high yield steel.
The most significant advantage of titanium is the ...
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Benefits and disadvantages of aluminium alloys as a replacement for structural steels in ships
My Answer.
Benefits: The major advantage of aluminum in ship building is its strength to density ratio. Aluminum has high tensile strength with less weight, which results in lowering the weight of ...
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How can I calculate the buoyant force on an object without knowing in advance the amount of water displaced?
Suppose I know the mass and volume of an object, as well as its exact shape and density distribution as a function of space (x,y,z). Without submerging it to determine the amount of water displaced, ...
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X-form and cross-form rudders in underwater control
What are the advantages of using X-form rudders in comparison to cross-form rudders?
Why do some submarines, torpedos and underwater autonomous vehicles use X-stern control?
X-stern:
Cross-form:
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Why are aircraft carriers so expensive to build? [closed]
The aircraft carrier USS Nimitz cost \$4.5bn. The cruise ship Allure of the Seas cost \$1.2bn. Why is the difference so huge?
user11311
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Name of a keel between the bilge keel and the main keel
I'm working on a seaplane and find myself doubting about the specific nautical term for a keel placed between the bilge keel and the main keel. This might be a bit academic in nature since I have a ...
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Hydrofoil for skeg-hung rudder with forward centre-of-effort
I am trying to see how much I can reduce the torque on a rudder post by changing the foil shape. I think I need a rudder with a centre-of-effort further ahead than average but I don't know what rudder ...
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Would a Flettner rotor make sense for an ocean cruising trawler?
A Flettner rotor can be used to provide propulsion for ship from the wind.
Would it make sense to fit a Flettner rotor to a full displacement expedition trawler in the 55-70 foot class like a ...
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Do submarines really have cranks for closing leaks?
It's common in submarine movies that when suffering some kind of shock (like a near miss by a torpedo or falling deep into a trench), water will start bursting into the cabin and the crew will run ...
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How to design a reinforced concrete ship keel?
I am building a small ship (or very large sailboat) that will have a concrete ballast at the base of the keel. I am looking to increase the weight of the concrete (lb/ft3), but I also want to maximize ...
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Do ships powered by nuclear reactors use water for shielding?
On a different Stack, I encountered an answer that was making a comparison to nuclear powered naval ships. It was stated that the physical shielding being used was various kinds of metals. This seems.....
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Why would you launch a large ship by dropping it sideways?
I'm referring to the process shown in this video:
https://youtu.be/Quyr5R1Rbfw?t=20
Or this image from Wikipedia:
In it, a large warship is launched into the water by essentially dropping it ...
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Purpose of spheres and fins on submarine propeller
On a recently launched Russian diesel-electric submarine, the rear propeller has two distinct features. You can see spheres at the base of every propeller blade:
Also, the trailing edge of the shaft ...
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