Comparison of Velocity Profile between Particle Image Velocimetry and CFD Analysis in a Scaled-down Facility for CANDU6 Moderator Tank

The CANDU6 moderator tank is the actual reactor core including fuel channels and moderator. It is also called as Calandria vessel. The ability of cooling in the reactor is related to the circulation characteristics of the moderator. Therefore, velocity and temperature distributions in the Calandria vessel are important considerations for the safety of the CANDU reactor. Various experimental and numerical efforts to predict and analyze the thermal-hydraulic characteristic of Calandria vessel have been made. Heget et al. carried out 2-dimensional moderator circulation tests at a 1/4 scaled-down facility in the Stern Laboratories in Canada. Laser Doppler Anememetry (LDA) was used to detect the velocity profile. Yoon et al. developed a CFD model for the CANDU6 moderator analyzing the velocity profile and the temperature distribution. There are many methods to analyze the velocity profile and the temperature distribution in Calandria vessel. In the present work, a Particle Image Velocimetry (PIV) technique is used in a scaled-down Calandria vessel to obtain velocity profiles. The experimental data for the velocity profile are compared with the result of CFD analysis