Numerical modeling of turbulent mixing in connected nuclear fuel subchannels

A numerical study on turbulent mixing in a gap-connected twin-subchannel geometry has been carried out. Results from an experimental study were used as the foundation for validating a computational fluid dynamics (CFD) model. The experimental study included measurements of flow velocities through the gap as well as total mixing along the length of a twin-subchannel test section. Consistent with the experimental process, the CFD modeling of mixing was carried out through the use of a tracer added to the flow. The current study extends previous work on modeling and characterizing flow and mixing within twin-subchannel geometries.