Page 88 - Intro to Space Sciences Spacecraft Applications

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Propulsion
3. Compare the answer obtained in Exercise 1 to the exhaust velocities
obtained for the other fueyoxidizer combinations given in the reading.
Use the same values for pJp, and y given in Exercise 1 above.
4. Compute the specific impulses for the three fueyoxidizer combina-
tions (based on the answers from Exercises 1 and 3 above) and com-
pare them to those given in the reading. What might be the reason for
any differences?
5. The Saturn V F-1 first-stage booster rocket used a kerosene/oxygen
propellant combination. Mass flow rate to each engine (there were five
in the first stage) was 5,736 Ib/sec and the combustion chamber pres-
sure was 1,122 psi. Determine the standard sea level exhaust velocity,
thrust, and specific impulse for one of the engines (assume y = 1.2).
What was the total sea level thrust of the Saturn V? Give your answers
in both English and metric units.
6. It is desired to launch a multistage rocket with a ratio of original mass
to burn-out mass for each stage of 2.0. For a nozzle design which main-
tains the exhaust velocity at 3,000 dsec, determine how many stages
would be necessary to place a payload into a circular low-earth orbit at
an altitude of 200 km, with a trajectory resulting in VJV- = 1.1.
7. Compute the three separate Av's required for the geostationary transfer
described in the reading. Assume an initial circular parking orbit of 450
km altitude at 28.5" inclination.