3rd eng
A propeller is to a ship or any marine vessel as tires/wheels to a car or any automobile. They help the vessel to move forward or backward and there are many different types of propellers which are used based on requirements, type of vessel and so forth.
Different Types of Propellers
When building a ship or any vessel, the naval architects decide on the best type of propeller that would suit the vessel based on the set of requirements specific to that vessel.
The whole idea is that the propeller should be able to cope up with the speed requirements and should utilize an optimum amount of energy in tune with the prime mover or the main marine engine. Normally in case of higher speed requirements a pair of propellers is used instead of a single propeller.
The propeller should be such that it can fit into the design of the ship easily. The use of multiple screw propellers is recommended in cases where the ship has a higher chance of meeting with accidents while sailing. This is exactly why these are used in war ships and in ice breakers. The multiple screw propellers are also used when the ship is required to sail smoothly even when it is in a high speed.
Let us now take a brief look at the different types of propellers which are found in common use.
CPP Propellers
A type of propeller that is generally used is the controllable pitch propeller. As the name itself suggests these types of propellers are used to ensure that in spite of the variation in the speed the ship remains in control and fuel efficiency is also maintained. This ensures that no matter what the speed, the ship runs smoothly. This is used in ships that may need to move in both high and low speeds like war ships for example. As they need to operate at various speeds.
Skewed Propeller
The skewed propeller is used in cruise ships that must ensure that the passengers on board experience the least vibrations and enjoy a smooth sail. When it comes to cruise luxury is the main point of concern and the luxury can only be experienced when the least vibrations are experienced on board. What this propeller does is that it increases the efficiency of the propeller but ensures that the propeller has the least impact on the hull. As a result the ship does not experience any strong vibrations unlike the other ships. As a result the guests cannot feel that they are in the high sea. They get peaceful night sleep and they enjoy the cruise.
Self Pitching Propellers
Self pitching propellers, is the next that we are going to discuss in the list of the various types of propellers that are used at the sea. These propellers are mostly used in small boats and yachts. These have high probability to face mechanical errors when fitted onto a large ship. This is exactly why they are used for small vessels and they are quite efficient.
I hope you now have a fair idea about the type of propellers. Apart from these type of propellers there are some more that must be mentioned.
Under Research & Development
Most of these types of propellers that we are going to discuss now are in research and development state. They need to be tested on bigger ships. However, they might be the future propellers so we thought they must be discussed in this article.
Tip Vortex Free Propellers/Balanced Thrust Loading Propellers
The first example is tip vortex free propeller this is still being researched on. It is expected that this will increase the efficiency of the propellers and make them more developed.
The other example is the balanced thrust loading propeller that when ready can change the way we propel ships forever. These two seem very promising concepts in ship propulsion. These are still in development stage.
Contra Rotating Propellers
Contra rotating propeller is now already being used in small ships to a certain extent. As of now these propellers have not been able to prove themselves in big ships. Perhaps with a little more research they too will be good enough for the big ships. They are every efficient as these are electric driven propellers. These are so effective that the use of gear box can be avoided when this propeller is used.
These are the various types of propellers that are used in ships all over the world. They ensure that the ships stay in course and have a smooth sail. The type of propellers has evolved a lot over the years from simple propeller to the most complex ones. Nevertheless, you must know the requirement of your ship and you must design propellers according to the requirement of the ship that is in question.
Different Types Of Propellers,
