Phase II Final Report - NASA's Institute for Advanced Concepts

Chapter 3.0 Vehicle Design
3.5 Fuel Storage and Production
Figure 3-164: PV Battery Power System Diagram
3.5.4 Fuel Storage System
The simplest fuel storage system is to just carry the fuel directly from Earth. Depending on the
type of fuel to be stored, certain precautions may be needed. This includes ensuring stability so
that the fuel does not react prematurely and maintaining a required temperature to ensure the
fuel does not freeze. A diagram of the fuel storage system is shown in Figure 3-165. The mass of
this system had to be determined. The analysis was similar to that for the cryogenic tank. An
energy balance was set up to determine the heat flow from the tank to the surroundings and the
power necessary to maintain a constant temperature within the tank. The hydrogen peroxide
temperature was maintained at 270° K. This temperature is above its freezing point of 261.5° K
and therefore allows for some margin in the design. The average environment temperature on
Mars of 215° K was used as the background temperature. Equations 3-47 through 3-55 were
used to calculate the heat transfer from the tank. Because of the relatively low temperature difference
between the desired temperature of the fuel and the surroundings, the insulation and
power required to maintain the fuel at the desired temperature were minimal. This analysis was
performed for various masses of hydrogen peroxide. The masses used corresponded to the total
amount that could be made by the various amounts of stored hydrogen used in the pressure and
cryogenic storage analysis. The total mass of the fuel storage system, including power production,
is shown in Figure 3-165.
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