Page:Project Longshot - Advanced Design Program Project Report.pdf/72

Rh

1. Tank Volume

The storage density for the fuel is .0708 tons per cubic meter. Therefore, the total volume needed is:

The radius of the fuel tanks is set at 2.5 meters and the length is then computed.

The total volume is divided by six, because six fuel tanks are used.

2. Tank Thickness

A. Interstellar cruise phase

Newton's equation, F=ma, is used to find the forces on the fuel tanks during flight. The maximum force will occur when the acceleration is a maximum. This is when the mass is a minimum for a constant thrust problem. In our case, the minimum mass is:

Therefore,

The maximum force possible on the tanks could then be:

A safety factor of 5 is now applied to find the design load.

Next, the tank area that the force is acting on is found.