In a fusion reactor like Tokamak, how is fuel injected without destroying the fuel injector?

Question

Plasma temperatures in a tokamak are around 100 million C.

Presumably for a power plant that will run for a long period of time, fuel will have to be injected and "burnt" products will have to be removed.

How will this be done without destroying the fuel injector from the superhot plasma? Is that even possible, or will we be forced to always shut down the operation when replacing fuel?

EDIT: Any device to inject or remove something must be nearby the plasma (not necessarily contacting it). I imagine the black body radiation of a 100 Million C substance causing some extreme radiation damage, not necessarily from alpha/beta particles, but simply from intense EM radiation.

Answer 1

The ash is removed by the divertor. Since everything in the ring is ionised you can selectively remove ions with a magnetic field using their charge to mas ratio. This is done by the divertor, which pulls out heavier ions while leaving the tritium and deuterium in the ring.

As for fuelling, that's basically easy as you don't need to inject much fuel since fusion is so efficient. Just inject hydrogen ions using a simple accelerator or even fire in tiny nuggets of frozen hydrogen and let them vaporise.