A few weeks ago I was searching for some information online when I came across this awesome community. I have been blown away by what I have gained and learnt so far on steemit and I am honestly still surprised how I did not discover this platform earlier. But then ”It’s better Late than Never”
I am so Excited and Really happy to finally join this awesome community of Great minds. My name is DANIEL, a graduate of mechanical Engineering from the Federal university of Technology Akure. Presently working on my masters in University of Ibadan. I am a deep rooted lover of science and technology and I love reading, research and watching action movies….. lol
I look forward to continue learning from this platform while I also contribute my quota by also sharing what I know. Overtime I am sure we would get to know one another better. For now, let’s get right to the business of the day.
I was watching a blockbuster movie several years ago when I saw how a submarine was used by the military to perform some really intense military operation. Ever since then I have nursed this very funny idea of one day travelling deep beneath the sea in freezing cold water for a whole week simply to explore.
I know you might think I must be out of my mind to nurse this kind of ridiculous idea, but hey I have just one life to live and I really want to make it count.
So today my topic is the operations of this unique innovation known as the submarine
Submarines are undoubtedly one of the most treasured military equipment till date because of how effective they are in carrying out stealth operations. Submarines came on board to serve as an anti-surface ship warfare to help out with defeating enemies due to the advantage they have of being able to be utilized above the surface of oceans and seas and deep beneath the surface. Submarines are uniquely difficult to track which makes them so powerful, so they can carry out their operations swiftly without being detected by enemies. Submarines can sink to the depth of the sea and rise to the surface of the sea or oceans effortlessly anytime the captain chooses.
Over the years as technology advances at a superb rate, submarines have also become more sophisticated and have more features that make them more comfortable for the sailors and the crew as they stay submerged for month under water as they carry out specific operations. For instance, Submarines are perfect tools for missile launch platforms because they can stay hidden deep within the sea for long periods of time and be ready to launch a missile as orders are given. Submarines are not limited to the military alone, they are also used for several deep sea scientific purpose, oil and gas pipeline inspection, oceanography, wreck exploration, recovery purposes, the list is endless.
Firstly, let’s take a look at how submarines control their buoyancy
I like to define Buoyancy of a submarine as its ability to rise, sink or float at certain depths. For the submarine to archive this herculean task it utilizes two highly important tanks known as ballast tank and trim tanks.
Submarines are designed and constructed to
have two covering to facilitate this process, there exist an outer and an inner covering with a wide empty space between them, this space is called a ballast tank. A submarine is quite huge, so to ensure the nose of the submarine can be controlled to move upward or downward effortlessly a tank is located at the front, this tank is called Trim tanks.
Submarines were constructed to have trim tank put in place primarily to maintain buoyancy particularly during the first phase of the submarine’s dive or when it makes a return to the surface, the operation to be performed would determine if the trim tank would be filled with water or air.
You might wonder where the submarine gets the air from?
There are highly compressed cylinders designed to fill the submarine with air, so for a submarine to stay on the surface of an ocean just like a ship the cylinders are opened and air flows into the ballast tank to the point where the overall density of the ocean or sea is greater than that of the submarine.
To dive into the ocean or sea for an operation from the surface, the air that is in the ballast tank is gradually vented and the valves are opened simultaneously so water can flow into the ballast tank. As the volume of water becomes larger, a corresponding increment in the weight of the submarine occurs, so at the point where the sea or ocean’s density around the submarine is lesser than that of the submarine, known as Negative buoyancy. Then downward movement of the submarine commences and it starts to sink gradually till it gets to the desired point deep beneath the sea or ocean.
For the submarine to maintain the same depth while it travels under water, the overall density of both the ocean or sea and the submarine must be equal. This point is known as Neutral buoyancy and this can be done by maintaining the weight of the submarine using the ballast tank to have a corresponding balance of air and water. With this the submarine can glide through water effortlessly.
When the captain wants to take the submarine upward, the submarine must obtain Positive buoyancy to make this upward movement. The captain achieves this by removing water from the ballast tanks while filling the tank with air at the same time using the highly compressed cylinders in the tank. So the more the tank gets filled with air, the more the average density of the submarine reduces till it obtains the positive buoyancy. it’s at this point the submarine starts travelling upwards gradually. If an emergency occurs and the submarine need to get to the surface really fast, the ballast tanks would be filled with air at extremely high pressure to facilitate a speedy upward travel.
When a submarine takes a dive into the water the amount of lift that it generates is as a result of the speed and the angle of tilt and speed. So to make movement easier for submarine they are designed with movable sets of short wing at their backs in such a way that when water moves over them, they force the vessel to be angled upward. This set of short wings are referred to as hydroplanes and are designed to control the angle of dive and when the submarine gets to its desired depth the wings are levelled so the submarine can travel through the depth of the ocean at the same level.
Next let’s take a look at how the engine of a submarine functions
Unlike jet engines, gasoline engines or even diesel engines that require a supply of oxygen to function, the engines of submarines are quite different because deep beneath seas and oceans there is really no air available, so very large submarines make use of Nuclear power for operations since they don’t require air to function optimally. Nuclear powered submarines are designed with a small nuclear reactor that powers the electric motors and propellers. These nuclear reactors are so effective since they can generate power both deep beneath the sea and right on the surface.
For smaller submarines, diesel engines could be used. This comes with a lot of limitations, for instance typically diesel engines can only function when the submarine is on the surface or travelling just below the surface of the seas or oceans. This type of Submarines is designed with huge batteries, because it is these batteries the submarines completely relies on to travel beneath the sea and ocean. So the batteries need to be charged fully by the electric generator being powered by the diesel engine of the submarine before the submarine can dive fully into the sea or ocean to travel underwater. So this significant limitation automatically puts a huge barrier on the duration of time a diesel powered submarine can travel underwater since it relies on just batteries.
Submarines are designed with a navigational equipment and charts to help the captains and crew travel underwater and get to their destination or locate a target, since it is really dark and they can barely see. Submarines make use of GPS when they are on the surface of seas and oceans to determine their location but once they travel deep underneath the water the GPS becomes inactive. So to adequately cater for this limitation submarines are designed with inertia guidance system to track their movements and direction when they are submerged. This method of tracking makes use of gyroscopes which can accurately track movements using internal information for a period of time, this information would have to be corrected from time to time using radar, GPS or other external data.
For submarines to determine the distance between them and their destination or targets, submarines emit pulses and makes use of computers to calculate the time it takes for the pulses to hit the target and travel back taking into consideration the speed of sound in water. This method is known as Active sound and navigation ranging. Sometimes the submarine can determine the location of targets by simply listening to the sound generated by the targets. This method is known as passive sound and navigation and ranging.
How the crew survive underwater for long period of time?
For an environment to be suitable for humans to live comfortably for a period of time, there are certain things that are not negotiable and the submarine is not an exception. The air must be breathable, constant fresh water must be available and the temperature must be suitable for the crew to survive deep beneath the sea and ocean in the submarine.
As humans we breathe in Oxygen and breathe out carbon dioxide, Since the submarine is an enclosed vessel, to maintain breathable air quality in a submarine, oxygen must constantly be in abundant quantity to avoid suffocation of the crew. The submarines are designed with systems that detect and monitors the level of oxygen, these systems are designed to constantly refill the oxygen in the submarine as it is consumed. Depending on the type of submarine Oxygen could be derived from pressurized tanks or by electrolysis.
Additionally, the carbon dioxide the crew exhales as well as the exhaled humidity must constantly be removed from the submarine, so the air doesn’t get concentrated with this gas. So scrubbers are used to remove excess carbon dioxide while dehumidifier or chemicals are required to remove moisture so it doesn’t condense on walls or machines in the submarine. For situation where dust, dirt and particles contaminate the air within the submarine, filters are used to remove them. Then burners are also used to remove gases from equipment or other sources within the submarine.
Submarine are designed with distillation mechanism which takes in sea water and converts it to fresh water suitable for the crew members for domestic use and for cooling of electronic equipment. The temperature within a submarine is conducive for humans because submarines are designed to be electrically heated, so regardless of the depth beneath the sea or ocean the submarine travels the temperature is maintained.
In conclusion, submarines are unique enclosed vessels, however they requires adequate precaution and effective monitoring of equipment in the vessel by the crew members to ensure their safety while they travel underwater to carry out operations.