Design and development of a steam turbine driven circulator for high temperature gas-cooled reactors

Abstract

Design optimization of high temperature gas-cooled power reactors with integration of the entire primary coolant system in a prestressed concrete reactor pressure vessel (PCRV) leads to stringent power, size, and environmental requirements for the primary coolant circulation equipment. To meet these requirements, the series steam turbine helium circulator (SSTHC) was conceived and developed by Gulf General Atomic. The SSTHC consists of a single stage axial-flow helium compressor driven by a single stage steam turbine. The compressor and the drive turbine are integrally attached to a single vertical shaft and overhung from a central bearing and seal housing. The drive turbines are in series with the power-producing main steam turbine. This paper discusses the design points of the compressor, drive turbine and auxiliary Pelton wheel drive, as well as the design requirements for the bearings and seal system. A general outline of the SSTHC development program carried out at Gulf General Atomic is given. The following areas are included in the development program: aerodynamics, compressor noise, primary coolant shutoff valve, water bearings and rotor dynamics, seals, blade vibration, and disk catcher. Further, a comprehensive series of transient tests on a circulator have been carried out.