Patent Number: 039740293
Section: claims

1. A gas-cooled nuclear reactor having A. a main circulatory system which includes a portion passing through the reactor core,  B. a gaseous coolant flowing through said circulatory system,  C. said circulatory system including at least one main energy converting unit, and  D. an auxiliary circulatory system for the gaseous coolant, 2. A nuclear reactor according to claim 1 having at least one closed cycle gas turbine as a main energy converting unit, and in which the gaseous coolant is used directly as the working fluid for the turbine. 3. A nuclear reactor according to claim 1 in which said auxiliary steam turbine is arranged to run continuously in operation of the reactor. 4. A nuclear reactor according to claim 3 in which the steam turbine is used to drive an auxiliary generator. 5. A nuclear reactor according to claim 2 in which a plurality of gas turbines are disposed around the reactor core, and a plurality of auxiliary boilers disposed around the reactor core between the gas turbines. 6. A nuclear reactor according to claim 5 wherein the gas turbines and the auxiliary boilers are accommodated in chambers formed within the thickness of a pressure vessel wall surrounding the reactor core. 7. A nuclear reactor according to claim 5 wherein the gas turbines and the auxiliary boilers are disposed within the space between a primary pressure vessel accommodating the reactor core and a secondary pressure vessel enclosing at least part of the wall of the primary pressure vessel. 8. A high temperature gas-cooled nuclear reactor according to claim 1 having means for cooling the gas between the reactor core and the auxiliary boiler or boilers. 9. A nuclear reactor according to claim 8 wherein the cooling means includes means for mixing the gas emerging from the reactor core with gas at a lower temperature. 10. A nuclear reactor according to claim 9 in which the or each said auxiliary circulatory system incorporates a by-pass circuit by which some of the gas leaving an associated auxiliary boiler is caused to by-pass the reactor core and mix with the heated gas leaving the core before the latter is fed back to the boiler. 11. A nuclear reactor according to claim 8, in which the thermal capacity of the auxiliary circulatory/steam turbine system is about 16% to 20% of the thermal capacity of the core.