The cavitation performance of an axial flow pump with inlet guide vanes for different flow rates is studied in this article.
The effects of inlet guide vanes on pump hydraulic performance and cavitation are investigated, where the total vapor
fraction of impeller zone (Ftv) is calculated to predict the critical net positive suction head, which is compared with that
predicted by efficiency criterion for different flow rates. The influences of the development of cavitation on internal flow
in impeller zone are also investigated. The results obtained show that the cavitation performance of axial flow pump can
be improved at off-design flow conditions by adjusting angles of inlet guide vanes to positive values at low flow rates and
by regulating angles of inlet guide vanes to negative values at high flow rates. As the net positive suction head decreases,
the vapor fraction first increases slowly and then increases greatly, clearly presenting cavitation process from inception
to full development, which can be used to predict the required net positive suction head. When net positive suction
head decreases to the value around required net positive suction head, the cavitation zone from tip of blade suction side
close to leading edge and the cavitation zone from hub part of the blade suction side connect together. After the connection,
the cavitation zones have great influence on the velocity flow, leading to the decrease in pump performance
