Design of the primary liquid-metal pump of the Myrrha research reactor

Authors

L. Mueller , T. Verstraete, T. Arts - von Karman Institute for Fluid Dynamics, Rhode Saint Genèse, Belgium

Abstract

This paper presents the design of a liquid-metal pump for the primary cooling system of the advanced nuclear reactor MYRRHA conceived by the Belgian research center (SCK·CEN). The focus of this report is on the rotor design of the pump, as the most crucial component of the entire machine especially regarding erosion. The single stage axial-flow pump has been designed with the optimization algorithm developed at the von Karman Institute for Fluid Dynamics (VKI) based on evolutionary methods. Two sequential optimization cycles have been applied to meet the required total head rise at design flow rate, while limiting the maximum velocity in the rotor tip section due to erosion. In the preliminary design phase, the meridional flow path and rotational speed have been assessed by a 1D-model in the hub, mid, and tip section of the rotor. The outcome of this rather simple but very fast approach is a moderate specific speed, high hub-to-tip ratio rotor of N _s = 70 and R _hub /R _tiptip = 0.88, respectively. In the second design step, accurate 3D-NavierStokes computations have been performed to design and automatically optimize the entire pump comprising the inlet section, the rotor and stator blade rows, and the diffuser. The high fidelity CFD analysis has been assisted by an Artificial Neural Network (ANN) to accelerate the optimization and to reduce the computational cost.