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| Area | = pi * r^2 |
| = pi * 2.5^2 | |
| = 19.635 m^27 |
So, the pressure will be:
| p | =F/A |
| = 4.62 kN / 19.635 m^2 | |
| = 235.54 N/m^2 |
The thickness of the tanks is now determined.
t = (P * r) / (2 * yield stress)
If we assume that we will use A1 1100-0, the yield stress is 3.45e7 N/m^2. This gives a thickness of:
| t | = (235.54 N/m^2*2.5 m)/(2*3.45e7 N/m^2) |
| = 8.53e-6 m or .00853 mm |
Therefore, the fuel tanks can be made from 2 mm A1 1100-0 sheets.
B. Orbital Maneuvers
Since the upper stages will require advanced upper stages, the forces on the spacecraft are not known. Through the use of staging, multiple burns per maneuver, and the use of a stronger aluminum alloy, the thickness of the fuel tanks can be kept at 2 mm.
