Influence of Relative Position of Flow Line Before and After Radial Guide Vane on Hydraulic Performance of Reactor Coolant Pump

In order to investigate the influence of the relative positions of the radial guide vane flow lines at the front and rear cover plates on the hydraulic performance of reactor coolant pumps, non-stationary numerical calculations are carried out for five groups of models with different circumferential relative positions of the front and rear flow lines of the guide vanes, using a global structured mesh and the RNG k–ε turbulence model. The influence of the relative position changes of the front and rear flow lines of the guide vanes on the external characteristicsand the pressure pulsation characteristicsof the Reactor Coolant Pump is analyzed. The results show that when the position of the front flow line is kept unchanged while the rear flow line is deflected circumferentially in the opposite direction of the impeller rotation (i.e., the front flow line of the guide vane is positioned ahead of the rear flow line), the flow field structure in the pressurized water chamber, especially in the discharge section, is improved, and the hydraulic loss inside the guide vane and the pressurized water chamber is reduced. Compared with the original model, the head of the reactor coolant pump increases by 0.60%, the efficiency improves by 0.66%, and the average amplitude of pressure pulsations at the dominant frequency decreases by 23.08%. Thus, the hydraulic performance of the reactor coolant pump is enhanced while its vibration performance is significantly optimized.