3. NATURE OF PHYSICAL PROBLEM SOLVED
The program performs the steady state thermohydraulic analysis of multirod fuel bundles cooled by an incompressible fluid under non-boiling conditions. The present 1a version of HERA considers a hexagonal fuel rod assembly cooled by sodium. It essentially applies to bundles of bare rods and to bundles with grid type spacers. It may also be used for bundles with helical spacers, but intersubchannel transport phenomena at the edge of the bundle are not described in an entirely satisfactory way.
HERA-1A computes subchannel coolant mass flow rates, subchannel coolant enthalpies and various derived parameters of engineering interest.