29-11-2010, 10:56 AM
In aerospike engine instead of firing the exhaust out of a small hole in the middle of a bell, it is fired along the outside edge of a wedge-shaped protrusion, the "spike". The spike forms one side of a virtual bell, with the other side being formed by the outside air . by this design we can over come the demerit of the conventional bell type nozzle (concept of bell nozzle is to efficiently direct the flow of exhaust gases from the rocket engine into one direction. but The exhaust would be a high-temperature mix of gases, has an effectively random momentum distribution, and if it is allowed to escape in that form, only a small part of the flow will be moving in the correct direction to contribute to forward thrust and other part of momentum would be random . so it never give thrust to rocket system )
The aerospike engine has two chief advantages over conventional rocket engines:
1.It automatically achieves close to maximum efficiency at both sea level and high altitude. A conventional engine would need to change the shape of its nozzle to achieve this.
2.The aerospike engine can change the direction of its thrust and steer by varying the rate at which fuel flows to different parts of the engine. No moving parts are needed, unlike in a conventional engine.
reference:
https://www.csulb.edu/colleges/coe/mae/v...2003.shtml
http://en.wikipediawiki/Aerospike_engine
http://www.nasa.gov/centers/marshall/new...spike.html
http://www.air-attackpage/5/NASA-SR-71-LASRE-Project.html
The aerospike engine has two chief advantages over conventional rocket engines:
1.It automatically achieves close to maximum efficiency at both sea level and high altitude. A conventional engine would need to change the shape of its nozzle to achieve this.
2.The aerospike engine can change the direction of its thrust and steer by varying the rate at which fuel flows to different parts of the engine. No moving parts are needed, unlike in a conventional engine.
reference:
https://www.csulb.edu/colleges/coe/mae/v...2003.shtml
http://en.wikipediawiki/Aerospike_engine
http://www.nasa.gov/centers/marshall/new...spike.html
http://www.air-attackpage/5/NASA-SR-71-LASRE-Project.html