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CarburetorThompson
CarburetorThompson
So in general there is two types of aircraft engines. Propeller and jet. Jet engines produce thrust, while propeller engines produce power
CarburetorThompson
CarburetorThompson
Because of this the performance of propeller engines degrades with an increase in velocity unlike jet engines where it remains constant. This is why there is no supersonic propeller aircraft
CarburetorThompson
CarburetorThompson
Propeller engines produce power which turns a propeller that in turn produces thrust. The engine has two types of horsepower brake horsepower and thrust horsepower. Break horsepower is the effective horsepower of the engine, while thrust horsepower is the power imparted onto the air by the propeller
CarburetorThompson
CarburetorThompson
Propeller efficiency is the ratio of BHP to THP. Just like a wing a propeller has a cord line, as it is just another airfoil. Fixed pitch propellers are fixed at the overall best angle of performance, while variable pitch propellers can move to different angles for the different legs of a flight
CarburetorThompson
CarburetorThompson
The left turning tendencies are the forces imparted on the aircraft that cause a lift turn in flight. This is mostly only seen on single engine piston aircraft. The four tendencies are torque reaction, asymmetric loading, corkscrewing effect, and gyroscopic action
CarburetorThompson
CarburetorThompson
Torque reaction demonstrates newton's third law. While the action is the force turning the propeller the reaction is the drive shaft of the engine turning the plane in the opposite direction
CarburetorThompson
CarburetorThompson
Asymmetric loading results from when the pitch of the aircraft causes the bottom of the propeller to move at a higher angle of attack then the top propeller causing a yaw to the left
CarburetorThompson
CarburetorThompson
Corkscrewing effect is how the slipstream created by the aircrafts propeller wraps around the aircraft, turning it and moving against the rudder
Prince_Azmiran_Myrian
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LilRora
LilRora
Do you accept outside input? I have a couple of issues with this.
CarburetorThompson
CarburetorThompson
Issues with me exposition onto SHF or issues with the laws of physics?
LilRora
LilRora
With the types of engines specifically. No problems from me regarding what you're doing here.
melchi
melchi
The only issue is that you didn't mention the pros and cons of a ram jet engine. There is more than one kind of jet engine.
CarburetorThompson
CarburetorThompson
That’s why I used the term in general. There is multiple kinds of engine but as far thrust production is concerned there is only the two. Ram jet, pulse jet, turbo fan, rocket, the internal make up will change but the difference doesn’t change the way they produce thrust and perform at different velocities
LilRora
LilRora
Okay, so I concede the first point I was going to make about types of engines. Technically I could argue that there are more types, but this is a nitpick, got your point. Rocket engines, however, are not included in that; I think you grouped them too broadly. Rocket engine and jet engine are both reaction engines, but a rocket engine is not a jet engine.
LilRora
LilRora
Jet engines do lose efficiency both at low velocity and at high velocity. The former is because they partially or completely rely on incoming airflow to compress the air, the latter is a natural limitation of airbreathing engines - at some point, the air passing through the engine cannot be accelerated further.
LilRora
LilRora
Rocket engines are different however, in that they are not airbreathing engines and do not depend on the environment (this is why we use rocket engines in space). This makes their performance much more consistent regardless of velocity, enough that in simple calculations it can be taken as constant.
CarburetorThompson
CarburetorThompson
yes a rocket engine is very different from a jet engine, but not in this scenario. You are making this much more complicated then It needs to be. I’m talking purely about aerodynamic physics, not engine mechanics or systems.
CarburetorThompson
CarburetorThompson
In that regards the way a rocket engine directly produces thrust is no different from a jet engine which directly produces thrust They are effectively the same in a discussion of the physics of thrust, any performance difference is due to the construction of the engine, not because of the thrust production
CarburetorThompson
CarburetorThompson
This is different from a propeller aircraft where the difference in thrust production is affected by the velocity of the air. You could use an air breathing engine. turbine, electrical. It doesn’t matter it does not change how the propeller generates thrust
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