In conductive media like seawater, EM waves experience attenuation related to their frequency. The skin depth formula calculates the depth at which ##e^{-1}## attenuation is reached. The skin depth is inversely proportional to frequency.
In practical terms, only extremely low frequencies (eg 80...
I'm trying to figure out how I would calculate the rate at which a submarine (or any vaguely cylindrical object) ascends or descends in seawater given a certain buoyancy or change in buoyancy. For example, if my submarine is 2000 feet below sea level and weighs 393 metric tons (with empty...
I've read a lot about Gato / Balao / Tensch class submarines, the ones America used in WWII, and I can't seem to sort out the specific consequences of a dead battery. A lot of you are diesel experts, so maybe someone here knows?
Historical accounts are vague. Dead batteries are certainly a big...
Hi,
I was watching the following video.
Around 17:00 the following is said:
I tried to balance the chemical equation as presented in the video. Please have a look below. I don't see how the production of iron oxide yields more oxygen in the entire reaction. The heating of sodium chlorate...
Dear FEA experts,
I'm trying to model the mechanical behavior (static, modal, and buckling analyses) of an underwater floating structure (e.g. submarine capsule or buoy) under hydrostatic pressure by Finite Element Analysis.
To obtain feasible results, the structure should be modeled as freely...
I've often wondered how realistic the Seaquest DSV submarine design was.
Here are some attachments I've included:
https://www.pinterest.fr/pin/326651779206382460/
I would imagine that having windows on the sub would represent structural weakness and it's overall flatness design would make...
Homework Statement
A submarine is in water, depth 30 meters. Inside submarine there is default air pressure. Submarine has volume of 125 m³, from which 10 m³ is water tank used for submerging. Submarine weights 123 tons. How large portion of the water tank has to be filled with sea water in...
Homework Statement
An ocean-going research submarine has a 40.0 cm -diameter window 9.00 cm thick. The manufacturer says the window can withstand forces up to 1.20×106 N . What is the submarine's maximum safe depth? The pressure inside the submarine is maintained at 1.0 atm.
ρseawater = 1030...
I realized that this movie is now 50 years old. That goes for anything else in 1968 of course. This was animation quite different from Disney. A really good band did the music too. Have we seen this movie?
Homework Statement
A submarine of mass 80 000 kg is floating at rest (neutrally buoyant) at a depth of 200 m in sea water. It starts pumping out sea water from its ballast tanks at a rate of 600 litres per minute, thus affecting both its mass and the buoyancy force. Determine the vertical...
Homework Statement
Hi I have uploaded a picture of a pressure question.
It says that there is a submarine 325 m deep, with the sea water of density 1150Kg m-3 and acceleration of gravity 10m/s and the volume of the submarine is 0.2m3 with mass 480Kg
They first ask for the upthrust.
Then they...
How deep can a submarine volcanic vent be and still generate a significant pumice raft ?
Sadly, Wiki is a stub, and most of the relevant literature is pay-walled.
As I understand it, deep vents may generate a lot of pumice, but it never reaches the surface, just stays on the vent's flanks...
Here is a scenario to further explain. Let's say I am traveling inside of a submarine. I travel within a depth of 100 to 600 feet deep or 4 to 19 atmospheres. How would I and my submarine be affected if there were a hurricane, tsunami, or hurricane above the ocean.
Furthermore, does the...
How do nuclear submarines (and also newer technologies such as air independent propulsion submarines) get rid of the waste heat generated by their power plants given the high pressure environment they work in and their need for stealth?
Submarines that had lead acid batteries and were depth charged during WW1 or WW2 sometimes produced chlorine gas inside the submarine. Was that because;
1. Broken batteries leaked sulphuric acid into the bilges where sea water with NaCl had accumulated, or;
2. Leaking seawater flooded the...
Today I learned how easy it is to create and visualize toroidal vortices in a swimming pool. I bet this could be done in a bathtub.
Do moving submarines create a big toroidal vortex around themselves?
Homework Statement
A small spherical under water ROV (remotely operated vehicle) has a radius of 0.5m and a mass of 450kg. It sinks or rises in the ocean by taking water on board or pumping it back out again. How much water must it take on board to sink at a constant velocity of 1.2m/s. The...
Homework Statement
As a submarine dives, the pressure on its hull..
a. remains constant
b. increases
c. depends on the decrease in volume of the submarine
d . decreases
e. depends on the thickeness of the walls of the submarine
Homework Equations
P = F / A
The Attempt at a Solution
Not a...
Would a water pump for pressure be required for a submarine outfall for storm water drainage ?
Diameter of pipe 2 meters
Gradient 50
Horizontal distance from shore to outfall 200 meters depth about 16 meters, sine 50
Or would the pressure from gravity gradient be sufficient to overcome...
I am designing a submarine in low scale that the max propeller OD is 10 cm, means from center of shaft to propeller edge I have around 5 cm distance.
I am trying to find the maximum thrust as this submarine suppose to pull an object inside water pipe.
I need to find optimum rpm ,blade number...
Brief Summary of Question:
One submarine starts with a neutral buoyancy 100m below the surface when it displaces 8.9m^3 of water from its ballast tanks. If the mass of the submarine is 69 metric tons what is the initial, vertical acceleration of the submarine immediately after displacing the...
Homework Statement
A seal sees a shark 53.0 m away and let's out a
squeal. If the speed of sound through sea water
is 1533 m/s, how long will it take for the echo
of the squeal to return to the seal?
Homework EquationsThe Attempt at a Solution
i used the doppler effect formula and got...
Homework Statement
driving his homemade submarine underwater in a nearby lake. His instruments tell him that the sub is traveling at 8 m/s relative to the surrounding water and that the sub is oriented due north (nose pointing north). After two minutes, however, he ends up crashing into a...
Homework Statement
1.)
A projectile is fired from a submarine traveling horizontally at 20 m/s with respect to the water as shown in the figure below. According to an observer on the submarine, the projectile is fired at 45° with an initial velocity of 60 m/s. After firing the projectile, the...
Homework Statement
A submarine-launched missile has a range of 4330 km.
(a) What launch speed is needed for this range when the launch angle is 45°?
(b) What is the total flight time?
(c) What would be the minimum launch speed at a 22° launch angle, used to "depress" the...
Hi people,
It may be a strange question, or impossible, but maybe you could help me out.
It's about submarines, high pressure and Bernoulli's law.
What if we build some kind of jet engine-like thing on the front of the submarine, not to 'pull' it forward, but to speed up the water...
Dear All,
I am designing a AUV and trying putting a bow thruster in the front. I am kinda confused that how much power do I need to turn my AUV by a steady angular velocity. Could anyone pls help me with this.
Regards
This question may be impossible to answer without specific knowledge of vintage aircraft engines but maybe not.
How does this airplane...
come out of the wave running? It seems like running a piston engine underwater would result in ingestion of water and hydro-lock.
I'm not an...
1. A research submarine has a 20cm diameter window, 8cm thick. The manufacturer says the window can withstand forces up to 10^6N. What is the submarine's maximum safe depth? The pressure inside the submarine is maintained at 1atm.
2. Homework Equations P = P(atmosphere) + ρ*g*h
3. I...
Homework Statement
A submarine maintains 100 kPa inside it and dives 250 m down in the ocean having an average density of 1030 kg/m^{3}. What is the pressure difference between the inside and the outside of the submarine in kPa?Homework Equations
The Attempt at a Solution
I am quite confused...
I'm working on the design for a dry-hull model submarine. My plan is to cast the hull shape that I want out of aluminum because this type of casting is cheap, easy to make, and because aluminum has a good strength to weight ratio. I want the hull to be able to withstand an external pressure of...
Supplee's submarine paradox arises when you consider a submarine moving horizontally at relativistic speeds. (Never mind that this would obviously destroy the sub.) When at rest, the sub was neutrally buoyant. In the moving sub's frame, the water is more dense, so buoyancy is increased, and the...
I was browsing the 1998 STEP paper 3 (like you do) and come across a question related to a real intelligence gathering problem.
It has some simplifications and probably invalid assumptions, but is still quite interesting.
The question is:
I don't intend to solve this since the only question...
Hello I'm having trouble with answering this question: Certain submarines are capable of speeds in excess of 30 knots. What is the total pressure sensed at the nose of a submarine if the vessel is at periscope depth (5 m) and a speed of 30 knots? (Assume a constant sea-water density of 1030...
Hello, I'm working on a project, and my teacher gave me something to think about, but I am at a loss. He wants me to come up with an equation to model the maximum height a submarine can go underwater, if it can withstand a maximum pressure of 80kpa. I started thinking it was an integral...
Homework Statement
A submarine that weighs 10,000kg in air and has a volume of 12m3 floats in a harbor. How much of its volume do we need to flood in order to just begin sinking it in salt water with a density 1.02 g/cm3?
Homework Equations
The Attempt at a Solution
Fgravity = mass...
A submarine sonar system sends a burst of sound with a frequency of 325Hz. The sound wave bounces off an underwater rock face and returns to the submarine in 8.50s. If the wavelength of the sound is 4.71m, how far away is the rock face? (Ans: 6.51km )
--
v=fλ
λ=wavelength
f=frequency...
Homework Statement
A stationary destroyer is equipped with sonar that sends out pulses of sound at 49.0 MHz. Reflected pulses are received from a submarine directly below with a time delay of 60.0 ms at a frequency of 48.966 MHz. If the speed of sound in seawater is 1.58 km/s, what is the...
ok a model submarine, so not as exciting as the title suggests! This is a pretty basic physics question so forgive me, I'm just trying to clarify in my own head the increase in water displacement with a decrease in gas pressure. Basically as shown in the diagram below I have a model of the...
The pressure in a submarine inside water
P=h*ρ*g+Pa
Okay,
Since there's Atmospheric pressure inside the submarine (Pa),we calculate the total pressure on the submarine from the relation=h*density*g
we just neglect the atmospheric pressure
why?I don't understand?
Why don't we calculate the...
First law of thermodynamics
Hallo,
i hope someone can help me with the following question:
A submarine contaiins 1000m^3 of air and has a temperature and pressure of 15°C and 0.1MPa respectively. Due to the cold seawater a heatflow of 60 MJ/h occurs. The machines on the otherhand add...
First law of thermodynamics
Hallo,
I hope someone can help me with the following question:
A submarine conatins 1000m^3 of air and has a temperature and pressure of 15°C and 0.1MPa respectively. Due to the cold seawater a heatflow of 60 MJ/h occurs. The machines on the otherhand adds...
Bouyancy
Question:
A 3000m^3 submarine of mass, m, is filled with air(density air =1.29kg/m^3) and is floating, submergerd, in seawater(density = 1400kg/m^3)
a) draw diagram.
b) Write an equation that that equates weight of the sub to the buoyant force( include weight of air)?
c)...
Homework Statement
What is the total pressure (absolute pressure) against the porthole of a submarine, when the
submarine is at a 35 m depth, and the density of the seawater is 1020 kg/m3. Air pressure is 1
bar and 1 bar = 1×105 Pa. Give the result using unit bar.
Homework Equations...
Homework Statement
A submarine can use sonar (sound traveling through water) to determine its distance from other objects. The time between the emission of a sound pulse (a “ping”) and the detection of its echo can be used to determine such distances. Alternatively, by measuring the time...
Homework Statement
A French and a U.S. submarine are moving directly towards each other during manoeuvres in still water. The French submarine is moving at 50.0 km.hr-1. It sends out a sonar signal at 1100.0 Hz. The frequency detected by the French submarine (reflected back from the U.S...
Homework Statement
A submarine called the Deep View 66 is currently being developed to take 66 tourists at a time on sightseeing trips to tropical coral reefs. According to guidelines of the American Society of Mechanical Engineers (ASME), to be safe for human occupancy the Deep View 66...
Lets say I was going to build a submarine, how could I determine most accurately the resistive forces as it is traveling in sea water at a constant velocity. I need to know how much energy it would consume per km. Cant find anything about this online..
Thanks in advance!