/sci/ - Science & Math

>>14874997
>>14875011
Zubrin made an argument against nuclear electric disguised as an argument against the thruster, which is in part the fault of Chang-Diaz, also an ardent nuclearfag, for suggesting it be powered this way and pulling the idea of a 39 day transit out of his ass in hopes of getting funding when a reactor with an alpha of <1 kg/kW is the work of science fiction. As a comparison, the reactor for JIMO would have on paper been approximately 30 kg/kW including the heat rejection system but according to Kirk Sorensen who worked on the project they weren't close to meeting it. They even admitted in the VASIMR paper that <10 kg/kW isn't achievable with any turbo-Brayton reactor.

VASIMR accomplishes nothing that couldn't be done by nested hall thrusters like the X3, at the expense of a much lower TRL. They keep making excuses for why they can't even get it running for 100 hours. It's vaporware and cannot address the fundamental problem with nuclear electric.
>>14875060
The thrust to power ratio is just a function of its power efficiency and specific impulse. Thruster mass actually matters little compared to power system mass. VASIMR could literally weigh nothing and be 100% efficient instead of 73% efficient, it still wouldn't support the claims made by Diaz.