You can learn about different parts of the helicopter, their functions and operations. A very useful air transport vehicle. His first working VS-300 helicopter was designed by Igor Sikorsky of the Vought Sikorsky Aircraft Division of United Aircraft Corporation. He left Stratford, Connecticut on September 14, 1939. Initially, he had one design for the main and tail rotors. The mechanics of a helicopter are the same as those of an airplane. It works on the principle of lift generation. Buoyancy is the upward force that overcomes weight and pushes you into the air. This is caused by the pressure difference between the top of the blade and the bottom of the blade. In the previous article, I explained about lift and drag. Now let's talk about creating a helicopter.
Engine
There are two main types of engines used in helicopters. The first is a reciprocating engine, the second is a turbine engine.
Reciprocating engine
Piston engines and reciprocating engines are basically used in small helicopters with a small payload. Reciprocating engines are primarily used in training helicopters due to their simplicity and ease of operation.
Turbine engine
Turbine engines are used in commercial helicopters. More powerful and used on various helicopters. Turbine engines operate quite differently than turbine engines used in aircraft. Turbine engines produce enormous amounts of power for their size, but are very expensive to operate. We know that 75% of the incoming airflow is used to cool the engine.
A turbine engine installed in a helicopter basically consists of:
compressor
combustion chamber
turbine and
transmission
1. Compressor
It is used to draw filtered air into a chamber called a plenum where the air is compressed. Compressed air is then sent to the combustion chamber to inject atomized fuel. The air-fuel mixture is ignited and expands. It produces huge amounts of energy. Combustion gases are channeled through a series of turbine wheels, causing them to rotate. These wheels power both the engine and the transmission. Varies from 20,000 to 51,600 rpm, depending on model. 2. Combustion chamber
In contrast to piston engines, in turbine engines the combustion process is a continuous process. A chamber in which an air-fuel mixture is ignited and continues to burn until fuel is present. When the engine is on and there is an interruption or disturbance of the air-fuel mixture, called a flameout, the engine restarts. Helicopters in particular have a special system called Auto to Relight that automatically ignites and starts combustion when the engine misfires.
2. Engine
There are two main types of engines used in helicopters. The first is a reciprocating engine, the second is a turbine engine.
3. Reciprocating engine
Piston engines and reciprocating engines are basically used in small helicopters with a small payload. Reciprocating engines are primarily used in training helicopters due to their simplicity and ease of operation.
4. Turbine engine
Turbine engines are used in commercial helicopters. More powerful and used on various helicopters. Turbine engines operate quite differently than turbine engines used in aircraft. Turbine engines produce enormous amounts of power for their size, but are very expensive to operate. We know that 75% of the incoming airflow is used to cool the engine.
A turbine engine installed in a helicopter basically consists of:
compressor
combustion chamber
turbine and
transmission
1. Compressor
It is used to draw filtered air into a chamber called a plenum where the air is compressed. Compressed air is then sent to the combustion chamber to inject atomized fuel. The air-fuel mixture is ignited and expands. It produces huge amounts of energy. Combustion gases are channeled through a series of turbine wheels, causing them to rotate. These wheels power both the engine and the transmission. Varies from 20,000 to 51,600 rpm, depending on model.
The engine will restart. Helicopters, in particular, have a special system called Autorotate that automatically ignites and initiates combustion in the event of an engine misfire.
Turbine
In helicopters, he uses a two-stage turbine to drive the engine. The first stage of the turbine is called the gas generator and the second stage is called the power turbine. This is indicated by N1 or N2. Both stages of the turbine are connected to a common shaft and mechanically coupled together. 4. Accessory gear
The engine gearbox contains all the gears needed to drive the helicopter components. Independent shafts connected to the N1 and N2 wheel turbines that power the attached gearbox. The first stage of the turbine is used to drive the components necessary to complete the turbine cycle. The second is dedicated to driving the main and tail rotors and is also used to operate the air conditioning system. air frame
It is made of metal wood or composite material, or a combination of the two, usually a composite material in which many layers of fiber-impregnated resin are bonded together to form a smooth panel. The airframe design incorporates engineering aerodynamics, materials technology and manufacturing processes to strike the right balance between performance reliability and overall cost.
Hull
A helicopter fuselage consists of a main body that houses a cabin that houses the crew, cargo, and passengers, as shown in the figure, which is the outer core of the frame. In particular, helicopters differ from helicopters in the pilot's seat. Most of the time the pilot sits on the right side, but in rare cases helicopter pilots sit on the left or center. rotor system
Rotors are one of the most important parts of a helicopter and are directly connected to the wings to create lift. It consists of a mast, hub and rotor blades. A mast is a metal shaft in the form of a hollow cylinder that rises or extends up to and is supported by the gearbox. The attachment points for the rotor blades are called hubs.
Swash plate
A swashplate is used to convert a fixed input into a rotating input that can be connected to the rotor blades. Two swashplates are used throughout the swashplate assembly.
wing
Helicopters fly on the same principle as airplanes. To keep a helicopter in the air, you also need aerodynamic forces that occur when air flows around the helicopter's rotor blades. Wings are one of the key parts that enable flight. The shape of the wing creates lift as it flies through the air. There are two types of wings
A symmetrical profile makes the top and bottom the same for less lift. However, for an asymmetric wing, the top and bottom surfaces are different and help generate lift. The advantage of an asymmetric airfoil is improved lift-to-drag ratio and more desirable stall characteristics. In the early stages of helicopters, asymmetric wings were not used because the center of pressure moved too much when the angle of attack changed. Factors affecting helicopter performance:
Height
Altitude is one of the most important factors in helicopter mechanics, affecting helicopter performance at air densities that decrease with increasing altitude. It is well known that higher densities require more power to hover and reduce speed. When a helicopter flies at high altitude and speed, parasitic drag forces demand less power because the air is less dense at that altitude.
Weight
Weight reduction is a goal for the entire aviation industry. Everyone wants it, but it's hard to get. Helicopter weight depends on size. As the weight of the helicopter increases, the excess power decreases, especially at low airspeeds, due to induced drag. A large gross weight affects the maximum altitude a helicopter can fly for a given power available in ground effect. Under all these conditions, we can conclude that the heavier the helicopter, the lower the maximum hovering altitude.
These are all important parts of helicopters and common mechanics. If in doubt, ask in the comments. If you like this article, don't forget to share it on your social networks. Please subscribe to his website for more informative articles. thank you for reading.
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