One major accident of interest in the High Temperature Gas-Cooled Reactors is the Pressurized Conduction Cooldown (PCC) scenario. The PCC scenario results in a loss of forced convection to the core, while the loop stays pressurized since there is no breach in the boundary. The coolant flows through the core driven by buoyancy forces. Experimental data is needed to validate the performances of CFD codes.
An experimental facility representing the core and upper plenum of a HTGR has been designed and constructed to perform natural circulation experiments. The test sections include multiple vertical heated channels representing the coolant flow paths within a typical prismatic core design. Channels are independently heated.
Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) techniques are being applied.
Non-Intrusive Temperature Measurement and Flow Visualization
Non-isothermal plume at Re = 500 in the Texas A&M Thermal Hydraulic Research Laboratory Scaled Upper Plenum High Temperature Gas-Cooled Reactor experimental facility captured using P-LIF displaying temperature and velocity simultaneously. These measurements are taken during the steady state phase of the experiment and demonstrate the plenum to plenum natural convection condition. The velocity color contour is applied to the velocity vectors in the video and the unit for velocity is m/s. The unit for the temperature profile is degrees Celsius.