Thermal–hydraulic system study of the HELOKA-LP helium loop using RELAP5-3D code

The thermal–hydraulic system analyses for the HELOKA-LP (Helium Loop Karlsruhe – Low Pressure) facility are presented. Typical operation ranges for the test section are mass flow rate between 12 and 120 g/s, inlet temperature between 10 and 250 °C and pressure level between 0.3 and 0.6 MPa. An orifice is used for the loop testing, for which different experiments are validated with appropriate simulations. Afterwards instead of the orifice, two most heated compartments of IFMIF (International Fusion Materials Irradiation Facility) HFTM (high flux test module) are simulated in HELOKA-LP. Using the system code REALP5-3D components in the loop are modeled as well as the main control strategy. With this model the loop dynamics in conditions relevant for the HFTM operation are analyzed and the thermal time constant of the compartment is estimated.