Cooling systems for nuclear reactors

Claim 1

IN A FLUID-COOLED NUCLEAR REACTORK, A REACTOR CELL COMPRING MEANS DEFINING A TANK FOR COLD COOLANT AND A TANK FOR HOT COOLANT, AN OUTER TUBE HAVING A CLOSED END AND AN INNER TUBE COAXIALLY DISPOSED IN THE OUTER END SAID OUTER AND INNER TUBES BEING SPACED FROM ONE ANOTHER BY AN ANNULAR PASSAGE THROUGH WHICH THE COOLANT FLOWS TOWARD SAID CLOSED OUTER TUBE END BEFORE FLOWING REENTRANTLY OVER FUEL ELEMENTS DISPOSED IN THE INNER TUBE, AN ANNULAR MEMBER CONNECTED TO ONE OF SAID OUTER AND INNER TUBES AND EXTENDING ACROSS THE PASSAGE IN SPACED RELATION TO THE CLOSED OUTER TUBE END TO DEFINE AN ANNULAR CHAMBER WITH THE RESPECTIVE PORTIONS OF THE OUTER AND INNER TUBES DISPOSED BETWEEN THE ANNULAR MEMBER AND THE CLOSED OUTER TUBE END, SAID OUTER TUBE HAVING AN INLET PORT COMMUNICATING WITH THE COLD COOLANT TANK AND SAID INNER TUBE HAVING AN OUTLET PORT OPERATIVELY COMMUNICATING WITH THE HOT COOLANT TANK, MEANS DEFINING A PASSAGEWAY IN THE ANNULAR MEMBER HAVING AN OPENING AT ONE END OPERATIVELY COMMUNICATING WITH ONE OF SAID INLET AND OUTLET PORTS AND AN OPENING AT THE OTHER END OPERTIVELY COMMUNICATING WITH ONE OF SAID ANNULAR CHAMBER AND SAID HOT COOLANT TANK RESPECTIVELY, AND MEANS FOR CAUSING RELATIVE ROTATION BETWEENSAID INNER AND OUTER TUBES WHEREBY FLOW-THROUGH BETWEEN THE COLD AND HOT COOLANT TANKS IS REGULATED BY ADJUSTING THE EXTENT OF OVERLAP BETWEEN SAID ONE OF THE INLET AND OUTLET PORTS AND THE OPENING OF THE PASSAGEWAY COMMUNICATING THEREWITH.