Keeping the orbits low enough, and/or intentionally going suborbital after docking/before starting the fuel transfer, will make the chances of that being possible very low.
It's also worth considering that they have demonstrated cryo propellant pumping between two tanks within a ship, so, AFAIK, transfer between two ships is more about testing the docking systems, than it is about the pumps. They could probably rig the system to first pump some inert gas to verify the quality of the docking, then try to pump propellants.
Liquid handling in microgravity has always been weird. Big gas bubbles in the fluid, surface tension effects causing liquid to float in balls in the ullage, stuff like that. Turbopumps break if they ingest a larger bubble.
There could be some odd failure modes I would think. Failure to pump the liquid, broken pumps, who really knows? My guess would be that a failure mode would be a big spill, a failure to pump, only partially refilling, or broken turbopumps before an explosion.
> what will happen if orbit refuelling goes wrong? Won't it destroy everything in orbit?
No. What is the mechanism through which you suspected this could happen?
Kessler syndrome presumably?
Keeping the orbits low enough, and/or intentionally going suborbital after docking/before starting the fuel transfer, will make the chances of that being possible very low.
It's also worth considering that they have demonstrated cryo propellant pumping between two tanks within a ship, so, AFAIK, transfer between two ships is more about testing the docking systems, than it is about the pumps. They could probably rig the system to first pump some inert gas to verify the quality of the docking, then try to pump propellants.
...caused by what?
Presumably the effect of any explosion would decrease proportional to the volume as it expands. Is there much volume in space?
Liquid handling in microgravity has always been weird. Big gas bubbles in the fluid, surface tension effects causing liquid to float in balls in the ullage, stuff like that. Turbopumps break if they ingest a larger bubble.
There could be some odd failure modes I would think. Failure to pump the liquid, broken pumps, who really knows? My guess would be that a failure mode would be a big spill, a failure to pump, only partially refilling, or broken turbopumps before an explosion.
A probably very naive question: why not pistons?
Seems like you could use peristaltic pumps
That would take ages!