High speed jets used in rocket engines

In summary: The design considerations for the exhaust outlets on rockets and jets are different for a couple reasons. First, the exhaust on a rocket is designed to be hot and high velocity. Second, the exhaust on a jet is designed to be low velocity and/or hot.
  • #1
Asif
5
0
Ok, so I feel really stupid asking this question, but I guess you've got to start somewhere to reach somewhere, so here goes nothing:

I have this report to write and the title of the report has got me a bit confused. The professor's asked me to "write and present a technical report abut high speed jets as used in rocket engines".

Now, I'm a total novice in the area of jet/rocket propulsion. Whilst doing some research on the internet, I learned that jet engines are different from rocket engines, in terms of where they get their oxidizer from.

This is the part that's got me confused, if jet engines are different from rocket engines, then what does the professor mean when he asked about "high speed jets as used in rocket engines"?

Or have I totally misunderstood the professor, and he is simply asking me to write about rocket engines, how they work, etc.?

Your help would be appreciated.

Bye.
 
Physics news on Phys.org
  • #2
"Jets" is a bit of a misnomer, but understandable. Your prof. is referring to the rocket engines.
 
  • #3
IIRC, jets are normally 'air' breathing engines, i.e. the oxidizer (oxygen in air) is supplied through the front end through a diffuser section and perhaps facilitated by a compressor, passed to the combustion chamber, and the resulting combustion products are exhausted for propulsion - basically an open system.

Some missiles like the Bomarc and Snark used jet engines. IIRC, Bomarc had 2 ramjets and solid rocket motor booster to get the missile to the speed where the ramjets kicked in.

A rocket motor involves a closed system where the oxidizer (e.g. liquid oxygen) is injected with the liquid fuel into the combustion chamber, or in the case of a solid propellant - fuel and oxidizer are intimately mixed and the combustion takes place at one end of the solid fuel and progresses in a burn front, or in a central bore - as in the Shuttles SRB's.
 
  • #4
Asif said:
Ok, so I feel really stupid asking this question, but I guess you've got to start somewhere to reach somewhere, so here goes nothing:

I have this report to write and the title of the report has got me a bit confused. The professor's asked me to "write and present a technical report abut high speed jets as used in rocket engines".

Now, I'm a total novice in the area of jet/rocket propulsion. Whilst doing some research on the internet, I learned that jet engines are different from rocket engines, in terms of where they get their oxidizer from.

This is the part that's got me confused, if jet engines are different from rocket engines, then what does the professor mean when he asked about "high speed jets as used in rocket engines"?

Or have I totally misunderstood the professor, and he is simply asking me to write about rocket engines, how they work, etc.?

Your help would be appreciated.

Bye.

It seems kind of condesending to say but please don't take it that way, and it's not a stupid question if oyu don't know the answer.
THe first thing I would do is go back to your professor and ask him to clarify what he wants for this report and don't let up until you're clear about what he expects. Otherwise you may make an assumption and do a lot of work on a report that'll be nothing about what the professor wanted. :cry:

My next suggestion would be to pick Fred's brain clean :smile:
Sorry I can't be of much more help, the last report on jets and rockets I did was in HS and it was a very basic one about the histoy/developement of rocket and jet engines.

Fred: aside from the closed/open system difference between these engines aren't there different design considerations to take into account for the exhaust outlets on rockets and jets?
 

Related to High speed jets used in rocket engines

1. What is the purpose of using high speed jets in rocket engines?

High speed jets are used in rocket engines to provide the necessary thrust to lift the rocket off the ground and into space. They create a controlled explosion of fuel and oxidizer that propels the rocket forward at high speeds.

2. How are high speed jets created in rocket engines?

The high speed jets in rocket engines are created by combining a fuel, such as liquid hydrogen or kerosene, and an oxidizer, such as liquid oxygen or liquid fluorine, in a combustion chamber. The reaction between the two substances creates a high-temperature, high-pressure gas that is expelled through a nozzle, creating thrust.

3. How do high speed jets affect the performance of a rocket engine?

The speed and efficiency of the high speed jets directly impact the performance of a rocket engine. The higher the speed of the jets, the more thrust is generated, allowing the rocket to reach greater speeds and altitudes. Additionally, the design and shape of the nozzle can also affect the efficiency and direction of the thrust produced by the jets.

4. What are the advantages of using high speed jets in rocket engines?

The use of high speed jets in rocket engines allows for a more efficient and powerful propulsion system, making it possible for rockets to carry heavier payloads and travel further distances. They also provide a high level of control, allowing for precise maneuvers and adjustments during flight.

5. Are there any potential safety concerns with high speed jets in rocket engines?

While high speed jets are necessary for rocket propulsion, they do pose some safety concerns. The extreme temperatures and pressures generated by the jets can be hazardous, and the potential for explosions or malfunctions must be carefully monitored and controlled. Proper safety measures and protocols must be in place to ensure the safe use of high speed jets in rocket engines.

Similar threads

Replies
3
Views
806
Replies
2
Views
2K
  • Aerospace Engineering
Replies
1
Views
2K
  • Aerospace Engineering
Replies
19
Views
15K
Replies
1
Views
826
  • Aerospace Engineering
Replies
2
Views
1K
  • Aerospace Engineering
Replies
2
Views
2K
Replies
11
Views
2K
Replies
5
Views
3K
  • Aerospace Engineering
2
Replies
35
Views
4K
Back
Top