# Study on critical speed of rotation in the multistage high speed centrifugal pumps rotors

Study on critical speed of rotation in the multistage high speed centrifugal pumps rotors

Yabin TianAnjie Hu

School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China

Corresponding Author Email:
tianyb2008@126.com
Page:
31-39
|
DOI:
https://doi.org/10.18280/ijht.360105
17 August 2017
|
Accepted:
1 December 2017
|
Published:
31 March 2018
| Citation

OPEN ACCESS

Abstract:

Apart from hydraulic performance, the critical rotate speed in wet operating condition (the liquid lubricant state) is an important parameter in the designing of the multistage high speed centrifugal pumps rotors. In this paper, the finite element dynamic model of the rotor in dry state (without lubricate) is analysed by the lubricant fluid applied to the disk and cylinder parts, and a resistance equation of the influence of the fluid is proposed based on the analysis. This resistance is then coupled into the dry state finite element dynamic model to obtain that of the wet state, which is considered as the fluid-solid coupled interaction. With this model, the study further studies the influence of several factors on the inherent frequency of the rotor, and simulates the bending and torsion formation of the physical model. Simulation results show that, when the fluid’s influence is considered, the inherent frequency of the rotor is very different from that of the dry state, and hence this influence cannot be neglected in the designing of the rotor. These results are also verified by corresponding experiments.

Keywords:

critical speed of rotation, fluid-structure interaction, multistage centrifugal pump, rotor dynamics.

1. Introduction
2. Mathematical Models
3. The Finite Elementmodelin Ansys
4. Analysis of the Rotor Dynamics
5. Experiment Verification
6. Conclusions
Acknowledgements
Nomenclature
References

[1] Sun K, Li YP, Roy U. (2017). A PLM-based data analytics approach for improving product development lead time in an engineer-to-order manufacturing firm. Mathematical Modelling of Engineering Problems 4(2): 69-74.

[2] Pal M, Sarkar G, Barai RK, Roy T. (2017). Design of different reference model based model reference adaptive controller for inversed model non-minimum phase system. Mathematical Modelling of Engineering Problems 4(2): 75-79.

[3] Zaoui FZ, Hanifi HA, Abderahman LY, Mustapha MH, Abdelouahed T, Djamel O. (2017). Free vibration analysis of functionally graded beams using a higher-order shear deformation theory. Mathematical Modelling of Engineering Problems 4(1): 7-12.

[4] Kalla S, Marcoux H, De Champlain A. (2015). CFD approach for modeling high and low combustion in a natural draft residential wood log stove. International Journal of Heat and Technology 33(1): 33-38.

[5] Zhi Y, Min QF. (2015). Hei river flood risk analysis based on coupling hydrodynamic simulation of 1-D and 2-D simulations. International Journal of Heat and Technology 33(1): 47-54.

[6] Lv SJ, Feng MQ. (2015). Three-dimensional numerical simulation of flow in Daliushu reach of the yellow river. International Journal of Heat and Technology 33(1): 107-114.

[7] Zhang H, Zhang XL, Ji SH. (2003). Recent development of fluid2structure interaction capabilities in ADINA system. Journal of Computers and Structures 81(8211): 1071-1085.

[8] Sigrist JF, Laine C, Peseux B. (2002). ANSYS computation of fluid2structure interaction: Numerical and experimental analysis of an elastic plate in contact with a compressible heavy fluid. Journal De Physique IV 12(PR11): 137-144.

[9] Tian YB, Qi XY. (2013). Influence of axial stress on critical rotational speed of multistage centrifugal pump rotor. Transactions of the Chinese Society of Agricultural Machinery (44): 55-58, 88.

[10] Moreira M, Antunes J, Pina H. (2000). A theoretical model for nonlinear orbital motions of rotors under fluid confinement. Journal of Fluids and Structures (14): 635-668.

[11] Moreira M, Antunes J, Pina H. (2003). An improved linear model for rotors subject to dissipative annular flows. Journal of Fluids and Structures (17): 813-832.

[12] Sun QG, Yu L. (2000). Study of dynamic characteristics for fluid machine rotor immersed in annular liquid flow. Power Eengineeing 20(5): 906-910.

[13] Gu CH, Yao XL, Chen Q.F. (2001). Study on fluid-solid coupling dynamic characteristics for the component of hydraulic turbines. Large Electric Machine and Hydraulic Turbine (6): 47-52.

[14] Xu CD, Zhang HY, Zhang XQ, Han LW, Wang RR, Wen QY, Ding LY. (2015). Numerical simulation of the impact of unit commitment optimization and divergence angle on the flow pattern of forebay. International Journal of Heat and Technology 33(2): 91-96.

[15] Liu DW, Chen DH, Li Q, Xu X, Peng X. (2015). Investigation on the correlation of CFD and EFD results for a supercritical wing. International Journal of Heat and Technology 33(3): 19-26.