Nuclear power reactor having a high, prompt negative temperature coefficient of reactivity

Claim 1

A POWER NUCLEAR REACTOR HAVING A HIGH, PROMPT NEGATIVE TEMPERATURE COEFFICIENT OF REACTIVITY, COMPRISING A PRESSURE VESSEL, A REACTIVE CORE WITHIN SAID VESSEL, SAID CORE INCLUDING A PLURALITY OF VERTICALLY EXTENDING ELONGATED TUBES, EACH OF SAID TUBES CONTAINING A HOMOGENEOUS MIXTURE OF A SOLID MODERATOR, A MATERIAL FISSIONABLE BY NEUTRONS OF THERMAL ENERGY AND A MATERIAL HAVING A NEUTRON ABSORPTION CROSS SECTION WHICH RISES SHARPLY WITH RISE IN TEMPERATURE ABOVE THE OPERATING TEMPERATURE OF THE REACTOR, AN ANNULAR REFLECTOR SURROUNDING SAID CORE, SAID REFLECTOR BEING DIVIDED INTO A PLURALITY OF SEGMENTS, MEANS MOUNTING SAID SEGMENTS FOR MOVEMENT RELATIVE TO SAID CORE BETWEEN POSITIONS NEAR SAID CORE AND POSITIONS OUTWARD THEREFROM, MEANS COUPLED TO SAID SEGMENTS FOR MOVING SAID SEGMENTS, AND MEANS BIASING SAID SEGMENTS TO SAID OUTWARD POSITIONS.