Implementation of structural elements in the E-SCPAE CFD model for transient simulations

E-SCAPE is an experimental facility with LBE as coolant at SCK CEN representing a scale mockup of the MYRRHA reactor.

The main goal of ESCAPE is to generate validation data for thermal hydraulic codes (system codes and CFD).

More specifically the setup was designed to validate the models in to code with respect to phenomena occurring in pool type reactors (3D flow)  during accidental scenario’s with transition from forced to natural circulation flow. The most typical scenario for this is the loss of the pumps during normal operation of the reactor.

When the pumps stop, the coolant flow is strongly reduced until buoyancy effects induce the natural circulation.

Typical phenomena of importance are the buoyancy driven flow (rising plumes) and the stratification in the large plena.

Currently, an E-SCAPE CFD model is available which is already used to make transient simulations. However, important structures such as the pipes of the loops are not modelled yet. The thermal inertia of these structures can play an important role during the transients.

The goal of this thesis is to model these structures, add these to the existing CFD model and investigate their effects on the temperature evolution into the system.