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rocketman83
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Can anyone break down the fundamentals of air propulsion? thank you. I also have a few other questions.
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Langbein said:What do you mean, the the equitation for a rocket engine, or what ?
Rocket engines, jet engines and propeller engines all have different equitations.
Please clarify what you are searching.
Langbein said:For a clean jet engine (Normally not used any more due to noice and high fuel consume.):
The air breathing engine is only useful if the velocity of the gas from the engine, c, is greater than the airplane velocity, v. The net engine thrust is the same as if the gas were emitted with the velocity c-v. So the pushing moment is actually equal to
S = m (c-v)
Most jet engines today is fan engines, but actually the basic formula should be the same ..
Langbein said:"Do you know anything about Jet packs?"
No, but I have been working with "real" jet engines F-16 among other.
Do you have a link to the "Jet Pack" ?
Langbein said:These looks basically like rocket engines and not jet engines.
When I look at the formulas I forst gave you they are not really jet engine formulas but rocket engine formulas (Wikipedia is not precise.)
S = m (c-v)
This should allmost be the formula for a rocket engine, a bit more accurate like this:
S = m*k(c-v)
Where S = trust in Newton, k = some constant, c = gassflow out of the rocket engine (m/s), v= speed of aircraft/rocket, m = massflow out of the rocket engine (kg/s)
Will have to sleap now but will look at the question tomorrow. I might find some of my old books with some more presice info.
Danger said:I didn't check out your links, but I will say that most 'jet-packs' that I've seen were peroxide rockets. They're inherently unstable, but not uncontrollable. The 'mileage', however, is pretty scary.
There are tons of other types of rocket engines other than HO rockets.rocketman83 said:I've read that about Jet Packs. Are there any other type of rockets other then Peroxide Rockets?
FredGarvin said:There are tons of other types of rocket engines other than HO rockets.
Danger said:Oh man... the variety is almost endless. You could use nitric acid and unsymmetrical dimethylhydrazine if you want to be the next national spokesman for Preparation H. Icing sugar and sulphur and potasium nitrate can be interesting. Then there's the ever popular kerosene/liquid oxygen combination as used in the Saturn V. Good old black powder works reasonably well, but there's an issue with throttleability...
Danger said:That would be the peroxide unit, which is why most of the focus has been in that area. As Fred mentioned, his company tried out a turbojet system. Others have as well. There are serious issues with all of them.
edit: Just caught your last post which you sneaked in while I was composing this one. I was actually referring to the LOX/kerosene rocket. Most jet engines use kerosene of some grade or another (Jet A, Jet B, etc.), but they can burn diesel or several other fuels. The same J-34 turbojet that burned premium jet fuel in military fighters is now on the dragstrip sucking diesel. Some others use propane or natural gas. One of the great things about jets is their versatile diet.
Danger said:Well, that was fiction after all. You might as well go for Iron Man's microturbo boot jets. I really am going to have to defer to Fred on this. I'm way out of my depth, and this is his area of expertise.
Air propulsion is the process of propelling an object forward or creating lift by utilizing the force of air. It is commonly used in aircraft engines, rockets, and other forms of transportation.
The basic principles of air propulsion involve Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. In the case of air propulsion, the action is the expulsion of air from a nozzle or engine, and the reaction is the movement of the object in the opposite direction.
There are several factors that can affect air propulsion, including the design and size of the propulsion system, the density and temperature of the air, and the speed and direction of the object being propelled. Other factors such as altitude, humidity, and air pressure can also play a role.
There are several types of air propulsion, including jet propulsion, rocket propulsion, and propeller propulsion. Jet propulsion involves the use of a gas turbine engine to create thrust, while rocket propulsion uses chemical reactions to generate thrust. Propeller propulsion uses the rotation of blades to move an object through air or water.
Air propulsion is used in a variety of modern technologies, including aircraft, spacecraft, missiles, and even some cars. It is also used in industrial applications such as fans, blowers, and pumps. Additionally, air propulsion is used in recreational activities such as paragliding and skydiving.