Fuel velocity vs exhaust velocity difference?

In summary, The conversation discusses the difference between fuel velocity and exhaust velocity. It is mentioned that fuel velocity is equal to rocket velocity minus exhaust velocity. Further explanation is given about how fuel velocity is the velocity of the fuel relative to earth, while exhaust velocity is the velocity of the fuel relative to the rocket. It is noted that exhaust velocity is constant due to the constant power of the rocket engine.
  • #1
liddojoe
1
0
hi all,

i've been confused about what the difference is between fuel velocity and exhaust velocity. apparently, fuel velocity is equal to rocket velocity minus exhaust velocity. attached are screenshots of the textbook reading that confused me. if anyone can explain this section to me, i would greatly appreciate it!

thanks!
joe
 

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  • #2
hi joe! welcome to pf! :smile:
liddojoe said:
i've been confused about what the difference is between fuel velocity and exhaust velocity. apparently, fuel velocity is equal to rocket velocity minus exhaust velocity.

fuel velocity, vfuel, is the velocity of the fuel (relative to earth)

exhaust velocity, vex, is the velocity of the fuel relative to the rocket

vex is constant (because the rocket engine has constant power) :wink:
 

FAQ: Fuel velocity vs exhaust velocity difference?

What is the difference between fuel velocity and exhaust velocity?

Fuel velocity refers to the speed at which fuel molecules are pushed through the engine, while exhaust velocity refers to the speed at which exhaust gases are expelled from the engine.

How do fuel velocity and exhaust velocity affect engine performance?

The difference between fuel velocity and exhaust velocity plays a crucial role in determining the overall efficiency of an engine. A higher fuel velocity can result in better fuel-air mixing and combustion, while a higher exhaust velocity can increase the engine's power output.

What factors can influence the difference between fuel velocity and exhaust velocity?

The difference between fuel velocity and exhaust velocity can be affected by various factors such as the design of the engine, fuel type, air-to-fuel ratio, and engine speed.

Is there an ideal difference between fuel velocity and exhaust velocity?

The ideal difference between fuel velocity and exhaust velocity can vary depending on the specific engine and its intended use. In general, a larger difference can result in better performance, but it also depends on other factors such as engine design and fuel efficiency goals.

How can the difference between fuel velocity and exhaust velocity be optimized?

To optimize the difference between fuel velocity and exhaust velocity, engine designers can make adjustments to factors such as fuel injection timing, air intake design, and exhaust system design. Additionally, using high-performance fuels and regularly maintaining the engine can also help improve this difference.

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