**Chuan Wang 1,3, Bo Hu 2, Yong Zhu 1,3,\*, Xiuli Wang 3, Can Luo <sup>1</sup> and Li Cheng 1,\***


Received: 30 April 2019; Accepted: 29 May 2019; Published: 1 June 2019

**Abstract:** A self-priming centrifugal pump can be used in various areas such as agricultural irrigation, urban greening, and building water-supply. In order to simulate the gas-water two-phase flow in the self-priming process of a self-priming centrifugal pump, the unsteady numerical calculation of a typical self-priming centrifugal pump was performed using the ANSYS Computational Fluid X (ANSYS CFX) software. It was found that the whole self-priming process of a self-priming pump can be divided into three stages: the initial self-priming stage, the middle self-priming stage, and the final self-priming stage. Moreover, the self-priming time of the initial and final self-priming stages accounts for a small percentage of the whole self-priming process, while the middle self-priming stage is the main stage in the self-priming process and further determines the length of the self-priming time.

**Keywords:** self-priming pump; gas-water two-phase flow; computational fluid dynamics
