Abstract
In turbopump inducers, cavitation on one blade can change incidence on the following blade, and this “blade-to-blade interaction” can lead to local cavitation instabilities such as alternate blade cavitation (ABC) and supersynchronous rotating cavitation. However, how the inducer operating condition (e.g., flow rate) affects the blade-to-blade interaction is still unknown. Therefore, for the first time, the dependence of blade-to-blade interaction on the inducer flow rate has been measured via fluorescent particle image velocimetry (fPIV) and high-speed visualization. The blade-to-blade interaction depends nonlinearly on the flow rate and is maximized at a certain flow rate, or certain incidence (). At the flow rate corresponding to , the cavity trailing edge on the leading blade is located near the inducer throat, and a sink-like flow is generated closest to the following blade’s leading edge, maximizing the blade-to-blade interaction. As the flow rate either increases or decreases from the flow rate corresponding to , the trailing edge of the leading blade cavity moves farther away (upstream and downstream) from the inducer throat, weakening the blade-to-blade interaction.