/sci/ - Science & Math

>>15561455
also, here's my 1000 hours in mspaint drawing of how a depot would work.

>>15129948
From another thread, about building orbital depots:
I think big spheres in space is likely how we're going to build propellant depots in space, initially in low earth orbit and eventually everywhere. I envision filling up the depots will happen in 2 ways: 1: dedicated tankers. 2: excess capacity will always be filled with propellant (or materials for the prop depot). For example, if starship has a capacity of 150 tonnes, and is launching a 100 tonne satellite to LEO, the ship would fill the remaining 50 tonnes with propellant to top up the depot.

Spherical tanks would be best because they give the most volume per surface area. A way to make these would be to bring up lots of standardized sections (such as a bunch of triangles to make a 20-sided-die shape, an isocahedron). These triangle pieces would be welded by robot into the correct shape -- the robot would have multiple arms, some with electromagnets to hold the pieces at the correct angle while welding. After the isocahedron is assembled, it's filled with an incompressible fluid and a small explosive charge. The explosive is set off, popping out the steel into a perfect sphere. https://www.youtube.com/watch?v=96yhdnhPxAw [Embed]

The sphere could then be covered with additional layers for micrometeor protection-- could be overwrapped with fiberglass/carbon, or additional shells of welded steel.

Multiple spheres could be joined into one massive structure, at least one sphere per type of propellant. These spheres would be sandwiched between 2 parallel planes: the sun-side would have solar panels to shade the tanks and generate power. The shady side would have heat exchangers to keep the propellants cool.

There are several possible ways to pump the propellant. A system of this size can't easily use ullage burns, so spinning the tanks and collecting the fluid using centrifugal scoops might work. Another way would be to have a bellows that inflate inside the tank and squeeze the fluid out.

>>15130438
I think big spheres in space is likely how we're going to build propellant depots in space, initially in low earth orbit and eventually everywhere. I envision filling up the depots will happen in 2 ways: 1: dedicated tankers. 2: excess capacity will always be filled with propellant (or materials for the prop depot). For example, if starship has a capacity of 150 tonnes, and is launching a 100 tonne satellite to LEO, the ship would fill the remaining 50 tonnes with propellant to top up the depot.

Spherical tanks would be best because they give the most volume per surface area. A way to make these would be to bring up lots of standardized sections (such as a bunch of triangles to make a 20-sided-die shape, an isocahedron). These triangle pieces would be welded by robot into the correct shape -- the robot would have multiple arms, some with electromagnets to hold the pieces at the correct angle while welding. After the isocahedron is assembled, it's filled with an incompressible fluid and a small explosive charge. The explosive is set off, popping out the steel into a perfect sphere. https://www.youtube.com/watch?v=96yhdnhPxAw

The sphere could then be covered with additional layers for micrometeor protection-- could be overwrapped with fiberglass/carbon, or additional shells of welded steel.

Multiple spheres could be joined into one massive structure, at least one sphere per type of propellant. These spheres would be sandwiched between 2 parallel planes: the sun-side would have solar panels to shade the tanks and generate power. The shady side would have heat exchangers to keep the propellants cool.

There are several possible ways to pump the propellant. A system of this size can't easily use ullage burns, so spinning the tanks and collecting the fluid using centrifugal scoops might work. Another way would be to have a bellows that inflate inside the tank and squeeze the fluid out.