A symmetrical-nonuniform angular repartition strategy for the vane blades to improve the energy conversion ability of the coolant pump in the pressurized water reactor

•A symmetric-nonuniform vane structure and its corresponding parameterized approach were proposed.•An optimization system comprised of the new vane design strategy and BP_Adaboost was proposed.•The parameter distributing laws determining the optimal structures were statistically analyzed.•Three optimal structures which can increase the exterior characteristics and decrease the pressure fluctuations were finally obtained.