NHDD 용 헬륨순환기의 개념설계를 위한 기초 기술분석

The helium circulator is the unique high speed rotating component in the Very High Temperature gascooled Reactor(VHTR) for the NHDD; it assures the reliable thermal energy transfer from the reactor core to the steam generator through the gaseous coolant and operates at more than 6.0 ㎫ of system pressure, 250 ℃ of helium temperature condition. The helium circulator in VHTR is a very complex machinery that consists of impeller / diffuser, motor and cooling system, rotor / bearing system, shut off valve, sealing / purification devices, instrument / monitoring system, etc. To meet the design requirement of the harsh operating condition, long duty lifetime, ease of maintenance and finally realize the reliable reactor operation, the application of the-state-of-the-art technology is highly required from the conceptual design stage. This paper deals with the basic analysis (or brief note) for the conceptual design on the NHDD He-Circulator. Big picture of the helium circulator design and its functional requirement are discussed.