Rotor-dynamic study for high pressure multistage centrifugal pump

Abstract Rotor-Dynamic behavior were closely related to the reliability, operability and cost effective for high pressure multistage centrifugal pump. The middle sealing sleeve, high-pressure sealing sleeve, front and rear rings of the impeller of the pump set were studied in this paper, by establishing a theoretical calculation model, numerical calculation methods. The leakage, radial force and tangential force of those seals under different working media and different sealing gaps were ccalculated in detail. The results showed that the sealing performance and dynamic characteristics were influenced by working medium and the sealing gap. The working medium had little effect on the radial force and tangential force of the middle sealing sleeve and high-pressure sealing sleeve, while with a greater effect on the front and rear rings of the impeller. The radial force of the middle shaft sleeve was closed with the sealing clearance. As the seal gap was 0.5mm, negative stiffness at low and high frequency whirlpools was more easily occured. With the gap increasing, the unbalanced response of the rotor increased significantly.