(497g) Simulation Studies of Coolant Flow Past Fuel Rod Bundles and Vibrational Lock-In Conditions in a Small Modular Reactor

Coolant flow past fuel rods and rod bundles in a small modular nuclear reactor (SMR) was simulated using ANSYS FLUENT 14.0. Over a range of transient flow conditions, the influence of the Strouhal number on vortex shedding past the fuel rods and corresponding patterns is studied in detail. The onset of the lock-in condition for cylindrical fuel rods in different fuel rod bundle arrays within an operating range of Strouhal numbers and the consequent variation in thermal profiles has been reported.