Stability of the axial-auto-balanced impeller of centrifugal pump

The pump is one of the most important energy consuming devices in an energy system. The axial force on a centrifugal pump is an important factor for improving the operation stability and the service life. Based on the Bernoulli’s equation, the formulas of the axial clearance are derived theoretically. The relationship between the impeller axial force, the clearance leakage flow rate and the axial clearance is obtained. The motion differential equation of the axial-auto-balanced impeller is established by the number axis modeling method. The asymptotic stability of the impeller is evaluated by the Lyapunov stability analysis. The transient simulation of the axial-auto-balanced impeller is carried out by the method of the computational fluid dynamics (CFD) with the dynamic mesh technology. The time required for the impeller to reach the stable state under different conditions is calculated. The effective values of the axial force are determined. This research is useful to improve the operation stability of the pump.