Analysis and study of transient characteristics of hydrogen circulation pump under different stopping modes.

The internal flow field of the hydrogen circulation pump becomes more complex and flow process becomes more intense during the stopping process, strong vibration is generated to the pump and the working life of the pump is shortened. Therefore, the pressure pulsation at the inlet and outlet section, the radial force characteristics of the active rotor and the transient flow mechanism of the internal flow under different stopping modes are studied in this paper. The results show that the intake pressure and exhaust flow change greatly in exponential stopping mode, while the pressure pulsation amplitude decreases with the increase of stopping time in linear stopping mode. In addition, the radial force value of the active rotor in the exponential stopping mode is significantly smaller than that in the linear stopping mode, and the direction of the radial force F x and F y point to the negative direction of their respective axes. In this paper, the dynamic mesh technology is used to design the corresponding rotating speed UDF according to different stopping functions, and then the transient simulation of the hydrogen circulation pump under different stopping modes is completed. Finally, the change law of pressure and flow pulsation, radial force characteristics and internal flow field under different stopping modes are analyzed. [Display omitted] • Effects of different stopping modes on flow characteristics are studied. • Pressure variation under different stopping modes are discussed. • Radial force of the rotor under different stopping modes are analyzed. • Working process is researched from the pressure and velocity distribution. [ABSTRACT FROM AUTHOR]