Non-inertial stopping characteristics of a prototype pump

The characteristics of centrifugal pump in non-inertial stopping period have not been studied better by far. In this article, the variation characteristics of transient performance of a prototype pump are clarified experimentally in five non-inertial stopping scenarios and three typical steady-flow rates. The effects of stopping time on the transient performance during stopping periods are explored. Meanwhile, three non-dimensional parameters are employed to analyze the transient behavior as well. The results show that the shorter the stopping time is, the more obvious the decline delay phenomenon in rotational speed is at the end of non-inertial stopping. There is an obvious decline delay phenomenon in flow rate at the beginning of stopping. With increasing steady flow rate before stopping, both head and flow rate decline faster. Despite the difference in stopping time, the static pressures at the pump outlet demonstrate a similar variation feature, while those at the pump inlet exhibit different characteristics. The head damping is the fastest and then the shaft power and the flow rate are followed. The non-dimensional instantaneous flow rate, head, and shaft power have a similar evolution characteristic overall. The affinity law for centrifugal pumps can be adopted to predict the transient performance under the condition of large steady flow rate and in the superslow stopping scenario.