In article om, Aidan
writes


Mr X wrote:

Why? Why is pumping not satisfactory?

I'd guess the pump/power can fail leaving the fuel burning but the
system unable to dissipate the heat. Temperature then increases, water
boils, pressure then increases if steam cannot be dissipated quickly
enough.

However, I'm not certain that a pumped system is prohibited.

Gravity circulation has fewer/no moving parts to fail. Circulation rate
increases as the temperature rises (assuming the heat dump can
dissipate the heat).

Thank you. See my reply to Christian
--
Mr X