Steam-Turbine-Driven Circulators for High-Temperature Gas-Cooled Reactors—Part II: Development

The High-Temperature Gas-Cooled reactor is characterized by integration of the primary coolant circuit and components within a Prestressed Concrete Pressure Vessel. This concept requires particular features and assurance in the circulators that are used to circulate the primary coolant fluid. Each circulator employs a single-stage axial compressor driven by a single-stage steam turbine which is in series with the main steam turbo-generator. The circulator is lubricated by water and is capable of variable speed operation. The conception and design of the circulator were discussed in the first part of this paper. The present part describes the experimental development program of the series steam-turbine-driven helium circulator, which verified and supported the design methods and demonstrated the operational capability of the circulator in all the possible modes that could occur in plant operation.