Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 12, 2022 - November 13, 2022
Industrial centrifugal pumps that require low NPSHR over a wide flow range, such as when pumping liquefied natural gas from storage tanks, are equipped with low solidity fan type inducers. Further improvement of pump suction performance is industrially expected because the lowest liquid level height that can be pumped directly affects the economic efficiency. In this study, several inducers made by a 3D printer were attached to an industrial centrifugal pump and investigated experimentally and using computational fluid dynamics to analyze the effect of the blade angle of the fan-type inducer on pump suction performance. The experimental results showed that the blade angle has no significant effect on the pump performance curve but has a clear influence on the pump suction performance, and CFD was used to investigate the cause of this for a flow rate with φ = 0.099, the design flow coefficient of the attached centrifugal pump. From the calculation results, the vapor volume was visualized and flow blockage due to cavitation in the internal flow path of the pump was analyzed. It was confirmed that the tendency of cavitation generation differs depending on the inducer vane angle even at the same cavitation number. Further analysis of the CFD results revealed that the influence of the swirling flow generated by the inducer on the flow field at the impeller inlet changed the occurrence of cavitation at the impeller inlet, leading to the occurrence of cavitation at the impeller inlet. As a result, the authors considered that there is a clear influence on the breakdown performance of the centrifugal pump.
